tag:theconversation.com,2011:/africa/topics/pests-2797/articlesPests – The Conversation2024-02-14T23:50:02Ztag:theconversation.com,2011:article/2226102024-02-14T23:50:02Z2024-02-14T23:50:02ZAustralia’s shot-hole borer beetle invasion has begun, but we don’t need to chop down every tree under attack<figure><img src="https://images.theconversation.com/files/574604/original/file-20240209-18-7stpt1.jpg?ixlib=rb-1.1.0&rect=46%2C0%2C6183%2C4147&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/shotgunlike-lesions-on-tree-bark-trunk-1754480912">jgeyser, Shutterstock</a></span></figcaption></figure><p>A <a href="https://www.agric.wa.gov.au/borer">new pest attacking Perth’s trees</a> threatens to <a href="https://www.outbreak.gov.au/current-outbreaks/polyphagous-shot-hole-borer">spread across Australia</a>, damaging crops and native forests as well as our urban forest. To control its spread, the Western Australian government is <a href="https://www.watoday.com.au/national/western-australia/absolutely-devastating-a-tiny-exotic-beetle-will-see-180-of-hyde-park-s-trees-cut-down-20240130-p5f16n.html">chopping down hundreds of established trees</a>. But these losses may be in vain. </p>
<p>Originally from southeast Asia, the polyphagous (meaning “many-eating”) shot-hole borer has <a href="https://doi.org/10.1079/cabicompendium.18360453">invaded several countries</a>. It attacks <a href="https://www.agric.wa.gov.au/sites/gateway/files/PSHB-WA-Host-List.pdf">more than 400 tree species</a>, including <a href="https://www.agric.wa.gov.au/sites/gateway/files/PSHB-Global-Host-List.pdf">crops</a> such as apple, avocado, macadamia and mango. <a href="https://doi.org/10.3389/ffgc.2021.654702">Trees grown for timber</a>, such as ash, elms and oaks are not safe either. And with every new country it invades, it threatens an increasingly large number of native trees.</p>
<p>Australia plans to <a href="https://www.watoday.com.au/national/western-australia/absolutely-devastating-a-tiny-exotic-beetle-will-see-180-of-hyde-park-s-trees-cut-down-20240130-p5f16n.html">eradicate this pest using one method: felling established trees</a>. But the borer has been eradicated only once – in <a href="https://doi.org/10.1007/s10530-022-02929-w">isolated tropical glasshouses in frosty Europe</a> – demonstrating the difficulty of eradication from larger agricultural and natural ecosystems.</p>
<p>To achieve this worthy but difficult goal, everyone will need to work together. We need a wide range of experts to fully evaluate all available control methods, and consider the most appropriate time frame for eradication. Understanding the impacts of both the pest and its management will ensure we get the best possible outcomes in both the short and long term.</p>
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Read more:
<a href="https://theconversation.com/trees-in-south-africa-are-under-attack-why-its-proving-hard-to-manage-130804">Trees in South Africa are under attack. Why it's proving hard to manage</a>
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<h2>The nature of the beast(s)</h2>
<p>The borer probably arrived in Australia as a stowaway with <a href="https://www.abc.net.au/news/2024-01-30/shot-hole-borer-attacks-hyde-park-trees/103406280">untreated wood</a> and remained undetected until August 2021, when a <a href="https://www.wa.gov.au/government/announcements/fremantle-residents-asked-look-exotic-insect-borer">concerned resident of East Fremantle</a> noticed unusual holes in her backyard maple trees. Now <a href="https://www.abc.net.au/news/2024-01-30/shot-hole-borer-attacks-hyde-park-trees/103406280">more than 80 suburbs</a> in 25 councils are affected. Fortunately, the pest has not yet been detected outside the Perth metropolitan area.</p>
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<a href="https://images.theconversation.com/files/575134/original/file-20240212-24-1b1k45.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A map of Perth and the Polyphagous shot-hole borer quarantine area" src="https://images.theconversation.com/files/575134/original/file-20240212-24-1b1k45.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/575134/original/file-20240212-24-1b1k45.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=848&fit=crop&dpr=1 600w, https://images.theconversation.com/files/575134/original/file-20240212-24-1b1k45.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=848&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/575134/original/file-20240212-24-1b1k45.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=848&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/575134/original/file-20240212-24-1b1k45.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1066&fit=crop&dpr=1 754w, https://images.theconversation.com/files/575134/original/file-20240212-24-1b1k45.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1066&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/575134/original/file-20240212-24-1b1k45.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1066&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The pest borer quarantine area covers 25 local government areas in Perth.</span>
<span class="attribution"><a class="source" href="https://www.agric.wa.gov.au/borer">Department of Primary Industries and Regional Development</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<p>The borer attacks so many tree species because it has an accomplice, in the <a href="https://doi.org/10.1016/j.fgb.2013.04.004">form of a fungus</a>. The two live in a mutually dependent “symbiotic” relationship. </p>
<p>The borer creates a Swiss cheese-like matrix of tunnels through the wood. The fungus feeds on the wood lining the tunnels as it grows, and the borer eats the fungus. </p>
<p>The tunnels weaken the structure of the wood, but tree death occurs when the fungus invades and blocks the <a href="https://doi.org/10.1038/s41598-023-48809-8">flow of water and sap between roots and leaves</a>.</p>
<p>The borer’s small size likely limits its natural rate of spread, however we <a href="https://doi.org/10.1111/afe.12321">don’t know how far it can fly</a>. There is a risk of human-assisted spread over long distances as the borer can survive in <a href="https://doi.org/10.1093/ee/nvaa103">small pieces of wood for weeks</a>. To make matters worse, a single female borer can <a href="https://doi.org/10.1111/afe.12155">produce offspring without a mate</a>.</p>
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<a href="https://images.theconversation.com/files/574813/original/file-20240211-22-c36zto.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Six development stages of the shot hole borer, arranged in a circle to show the life cycle, on a white background" src="https://images.theconversation.com/files/574813/original/file-20240211-22-c36zto.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/574813/original/file-20240211-22-c36zto.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=560&fit=crop&dpr=1 600w, https://images.theconversation.com/files/574813/original/file-20240211-22-c36zto.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=560&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/574813/original/file-20240211-22-c36zto.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=560&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/574813/original/file-20240211-22-c36zto.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=704&fit=crop&dpr=1 754w, https://images.theconversation.com/files/574813/original/file-20240211-22-c36zto.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=704&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/574813/original/file-20240211-22-c36zto.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=704&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The life cycle of the polyphagous shot-hole borer, also known as the Asian ambrosia beetle (<em>Euwallacea fornicatus</em>)</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/development-stages-asian-ambrosia-beetle-euwallacea-513402742">Protasov AN, Shutterstock</a></span>
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<h2>Responding to the threat in Australia</h2>
<p>The threat to Australia can be estimated from the experience in other invaded locations. As in Perth, the invasion usually begins in cities, then spreads into the surrounding countryside, attacking horticulture and forests, including <a href="https://doi.org/10.1007/s12600-012-0223-7">avocado production in Israel</a> and <a href="https://doi.org/10.1094/PDIS-03-12-0276-PDN">California</a> and <a href="https://doi.org/10.1007/s13314-023-00524-z">stone fruit in South Africa</a>. This overseas experience has informed models of <a href="https://doi.org/10.1111/afe.12566">potential impacts for WA</a>.</p>
<p>But local effects are hard to predict. Figs and eucalypts not susceptible in <a href="https://doi.org/10.3389/ffgc.2021.654702">California and Israel</a>, yet <a href="https://www.agric.wa.gov.au/sites/gateway/files/PSHB-WA-Host-List.pdf">figs are preferred and some eucalypts are susceptible in WA</a>.</p>
<p>The <a href="https://www.outbreak.gov.au/current-outbreaks/polyphagous-shot-hole-borer">national biosecurity response led by WA</a> has allocated A$41 million to eradicate the borer. This funding was based on an assessment of what it should cost. But there is only a short window of opportunity to effectively deploy these resources to achieve eradication.</p>
<p>The response includes trapping and surveillance to determine the spread of the pest. More than <a href="https://www.wa.gov.au/government/media-statements/Cook-Labor-Government/Vital-biosecurity-response-to-stop-invasive-beetle-pest-20240130">1.5 million trees on more than 50,000 properties</a> have been inspected and some 3,000 traps laid. </p>
<p>These traps catch flying beetles, which fly just once in their lives, so there’s a low catch probability. This makes it hard to detect false negatives, when no beetles are trapped but there are beetles in the area. This can be improved with alternative <a href="https://doi.org/10.7717/peerj.3656">trap designs</a> and <a href="https://doi.org/10.1371/journal.pone.0179416">chemical lures</a>.</p>
<p>When infested trees are found in WA, the response is “<a href="https://www.agric.wa.gov.au/borer">removing infested trees to save healthy trees</a>”. This could mean hundreds of trees at popular public locations such as <a href="https://www.wa.gov.au/government/media-statements/Cook-Labor-Government/Vital-biosecurity-response-to-stop-invasive-beetle-pest-20240130">Perth Zoo, Lake Claremont, Kings Park and Hyde Park</a> will be felled and chipped.</p>
<p>Continuing with the one control method, felling trees, will leave us with fewer trees, particularly if the eradication campaign runs for many years. Reduction of the <a href="https://theconversation.com/does-higher-density-city-development-leave-urban-forests-out-on-a-limb-57106">urban tree canopy</a> <a href="https://theconversation.com/fewer-trees-leave-the-outer-suburbs-out-in-the-heat-33299">could be profound</a>, and <a href="https://www.abc.net.au/news/2023-02-18/perth-tree-canopy-conference/101980438">Perth already has the sparsest urban tree canopy in the nation</a>. </p>
<p>The flow-on consequences could mean even <a href="https://theconversation.com/trees-are-a-citys-air-conditioners-so-why-are-we-pulling-them-out-21890">higher urban temperatures</a> and poorer <a href="https://doi.org/10.3389/fevo.2021.603757">human</a> <a href="https://doi.org/10.1016/j.amepre.2012.09.066">health</a>. </p>
<p>Urban trees are also valued for their beauty, shade and habitat for animals. All these benefits can be assigned a <a href="https://doi.org/10.1016/j.ufug.2017.11.017">significant monetary value, which would be even higher</a> if intrinsic or cultural value could be included.</p>
<h2>Waging war on the shot-hole borer</h2>
<p>Although felling and chipping entire trees is necessary, there are <a href="https://ipm.ucanr.edu/PMG/PESTNOTES/pn74179.html">other effective control methods</a>. Alternatives may include removing and chipping <a href="https://doi.org/10.1007/s12600-017-0598-6">infested branches only</a>, which may be more <a href="http://doi.org/10.3389/finsc.2023.1279547">cost-effective than felling entire trees</a>, to <a href="https://doi.org/10.1016/j.cropro.2020.105136">injecting at-risk but uninfested trees</a>, and <a href="https://doi.org/10.1094/PDIS-10-17-1569-RE">slowing</a> <a href="https://doi.org/10.1093/jee/toy423">infestations in trees</a> or spraying <a href="https://doi.org/10.3390/biom13040656">repellents onto uninfested trees</a>. In California, traps were developed into an <a href="https://www.californiaavocadogrowers.com/sites/default/files/Trapping-Optimization-and-Development-of-attract-and-kill-strategy-for-the-Polyphagous-Shot-Hole-Borer-in-avocado.pdf">attract-and-kill strategy</a> to tackle the borer in avocado orchards.</p>
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<a href="https://images.theconversation.com/files/574807/original/file-20240211-29-aulz4s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Polyphagous shot-hole borer trap set by the OC Parks Department and the University of California, in Irvine Regional Park. The large, multi-tiered black trap with a white collection vessel at the bottom is hanging from a metal pole." src="https://images.theconversation.com/files/574807/original/file-20240211-29-aulz4s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/574807/original/file-20240211-29-aulz4s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=898&fit=crop&dpr=1 600w, https://images.theconversation.com/files/574807/original/file-20240211-29-aulz4s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=898&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/574807/original/file-20240211-29-aulz4s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=898&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/574807/original/file-20240211-29-aulz4s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1129&fit=crop&dpr=1 754w, https://images.theconversation.com/files/574807/original/file-20240211-29-aulz4s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1129&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/574807/original/file-20240211-29-aulz4s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1129&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The best trap for the borer, developed in California, is not being used in Perth.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/orange-california-24-feb-2017-polyphagous-1938882280">Steve Cukrov, Shutterstock</a></span>
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<p>While a rapid response is crucial for eradication, we need to keep improving on this, using the most effective methods available. Relevant solutions from around the world suggest <a href="https://doi.org/10.1007/s10340-024-01744-7">broader community engagement</a>, beyond Perth, would be beneficial.</p>
<p>It is unclear what has been learned so far from efforts in WA. Is it still <a href="https://doi.org/10.1007/s10530-013-0529-5">feasible to eradicate the pest completely</a>? We need more experts to evaluate and advise on the response as it continues.</p>
<p>Making the right response choices will be crucial. Just consider other threatening invaders such as the <a href="https://www.outbreak.gov.au/current-outbreaks/red-imported-fire-ant">red imported</a> <a href="https://theconversation.com/how-to-know-if-were-winning-the-war-on-australias-fire-ant-invasion-and-what-to-do-if-we-arent-121367">fire ant</a>, the honey bee <a href="https://www.outbreak.gov.au/current-outbreaks/varroa-mite">varroa</a> <a href="https://theconversation.com/australia-has-officially-given-up-on-eradicating-the-varroa-mite-now-what-214002">mite</a>, and <a href="https://www.dcceew.gov.au/environment/invasive-species/diseases-fungi-and-parasites/myrtle-rust">myrtle</a> <a href="https://theconversation.com/myrtle-rust-is-devastating-australian-forests-a-new-high-tech-spray-holds-out-hope-for-native-trees-219411">rust</a>.</p>
<p>As the borer has only been detected in Perth, the window of opportunity is open now. Let’s make sure we have the best plan of attack so we can achieve eradication. </p>
<p>Australians pride themselves on working together to get things done. If we can bring everyone together to rapidly tackle this insect invasion, the whole nation will benefit.</p>
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<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>It’s a horror story unfolding in the west that could sweep across the country. Beware the shot-hole borer, an exotic pest that threatens our tree crops, plantations, urban forests and wild places.Theo Evans, Associate Professor, The University of Western AustraliaBruce Webber, Principal Research Scientist, CSIROLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2160292023-10-25T16:02:13Z2023-10-25T16:02:13ZBed bugs are a global problem, yet we still know so little about how they spread<figure><img src="https://images.theconversation.com/files/555558/original/file-20231024-23-yod6s8.jpg?ixlib=rb-1.1.0&rect=26%2C5%2C3472%2C2323&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Sleep tight...</span> <span class="attribution"><span class="source">Dr Richard Naylor</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Bed bugs have recently <a href="https://www.cntraveller.com/article/paris-bed-bugs-everything-you-need-to-know">exploded into the limelight</a> amid widespread reports of a major outbreak in Paris. The more people share photos of bed bug bites on social media, the more concerned we feel. That’s understandable, but the really worrying thing is the missing information – there is still no publicly available data about the infestations in Paris. </p>
<p>Indeed, data that confirms or denies the location and date of <em>any</em> bed bug cases is notoriously hard to find. The vast majority of people around the world go to the private sector for pest control, but data from this sector is often classed as “commercially sensitive” and not usually shared for research purposes.</p>
<p>Although it is not clear if the scale of the problem in Paris is real or social media hype, one thing is true: bed bugs are not just in the French capital. In fact, they are present in <a href="https://digitalmedia.sheffield.ac.uk/media/Bedbugs/1_fk8ko3mw/69389871">almost all human settlements</a> – there have been reports of bed bugs living with humans since our history began, with remains found in <a href="https://www.researchgate.net/publication/234040076_Cimex_lectularius_L_the_common_bed_bug_from_Pharaonic_Egypt">ancient Egypt</a>. </p>
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<p>Unlike a lot of other countries, the UK does at least have some data about bed bug infestations, as most local authorities <a href="https://www.gov.uk/report-pest-problem">do some bed bug control</a> for commercial and domestic infestations. They are a good source of data due to the powers of the UK’s <a href="https://ico.org.uk/for-organisations/foi-eir-and-access-to-information/guide-to-freedom-of-information/what-is-the-foi-act/#:%7E:text=The%20Freedom%20of%20Information%20Act%202000%20provides%20public%20access%20to,request%20information%20from%20public%20authorities.">Freedom of Information Act</a>.</p>
<h2>A seasonal spike</h2>
<p>I have researched the number of confirmed bed bug cases treated by local authorities in three major UK cities: Birmingham, Manchester and Sheffield. I used data on confirmed bed bug cases per month between 2009 and 2015, and ran this through a statistical model called a <a href="https://thedatalab.com/tech-blog/using-generalised-additive-mixed-models-gamms-to-predict-visitors-to-edinburgh-and-craigmillar-castles/">generalised additive mixed-effect model</a> (GAMM), which accounted for the size of each city and random variation between years. </p>
<p>The results showed a significant peak in bed bug cases around August and September each year (Figure 1), and also that bed bug numbers were steadily increasing (Figure 2). The same seasonal pattern and year-on-year increase was seen in the US city of Philadelphia between <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3955002/">2009 and 2011</a>, and <a href="https://academic.oup.com/jme/article/52/1/76/873440?login=true">in two Chinese cities in 2012/13</a>. In New York between 2010 and 2020, the seasonal pattern was the same but the numbers <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0268798">did not increase</a>.</p>
<p>More recent studies have looked at a region’s internet search history as a proxy for the prevalence of bed bug cases. When you find what you think is a bed bug, the first thing most people do is search the internet for answers. Studies <a href="https://academic.oup.com/jme/article/53/1/116/2459664?login=true">from the US</a> and <a href="https://www.jaad.org/article/S0190-9622(16)30092-5/fulltext">Australia</a> both found the same seasonal pattern in internet searches for bed bugs, although the pattern in Australia was the opposite to the northern hemisphere. </p>
<p>However, in order to tackle infestations, we need to understand more about these creatures. </p>
<h2>What we know about bed bugs</h2>
<p>Bed bugs are small, flightless insects that feed on human blood. There are several species, but the one most people know is called <em><a href="https://www.nhm.ac.uk/take-part/identify-nature/common-insect-pest-species-in-homes/bed-bug-cimex-lectularius-identification-guide.html">Cimex lectularius</a></em>. The Romans called them <em>Cimex</em>, which means bug. It was much later in 1758 that the natural historian Carl Linnaeus added “lectularius” to their name, meaning bed or couch. </p>
<p>Our blood is their main source of nutrition, but they will <a href="https://www.nhbs.com/monograph-of-cimicidae-hemiptera-heteroptera-book#:%7E:text=book%20Related%20titles-,About%20this%20book,which%20includes%20human%20bed%20bugs">feed on other animals</a> if they have to, including birds, pets and bats. Bed bugs have a complex gut microbiota, which helps them extract all the nutrients they need from our blood. </p>
<p>Juveniles require a blood meal in order to develop from one life stage to another – so, to become adult, each bed bug will need <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/9781119171539.ch16">at least five blood meals</a>. Adult bed bugs, though, <a href="https://www.vdacs.virginia.gov/pdf/bb-biology1.pdf">can survive an entire year</a> without a meal. </p>
<p>They can’t fly. As you can imagine, walking doesn’t get them very far, but it does allow them to spread around apartment blocks. And bed bugs hitch-hike on humans to move greater distances, although scientists can’t agree about exactly how they do this – it’s one of the unanswered questions about their ecology. People assume they travel on luggage, but it’s never been proven. </p>
<p>My <a href="https://www.nature.com/articles/s41598-017-11850-5">previous work in 2017</a> proved for the first time that they aggregate in dirty clothes in the absence of humans. My team put bed bugs in corrugated filter paper in the centre of a room, with clean and dirty clothes evenly spaced around them. The bed bugs all left the filter paper, and made a beeline for the dirty clothes nearly every time. This might explain how they get into our suitcases when we are travelling. </p>
<h2>How to stop their spread</h2>
<p>If we could understand more about bed bug dispersal and spatial distribution, we would stand a better chance of stopping their spread. </p>
<p>New York, which suffered a major outbreak <a href="https://www.theguardian.com/world/2010/oct/21/bedbugs-invaded-new-york">in the 2010s</a>, has shown it’s possible to tackle bed bug numbers if the public and private sectors work together. Pest control agencies <a href="https://www.npmapestworld.org/default/assets/file/newsroom/magazine/2015/nov-dec_2015.pdf">published data showing the scale of the problem</a> and <a href="https://www.nyc.gov/html/om/pdf/2010/dm_07-28-10.pdf">submitted a report</a> to officials with their recommendations for dealing with the outbreak. </p>
<p>According to the same <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0268798">report that confirmed the 2010 outbreak</a>, bed bug numbers in New York are declining. The researchers believe this is because of the pest management policies New York officials introduced from 2010. </p>
<p>First, they launched a <a href="https://www.nyc.gov/site/doh/health/health-topics/bedbugs.page">non-emergency helpline</a> for the public to call if they found bed bugs. The city also passed a policy where, from 2010, landlords were required to <a href="https://www.nyc.gov/site/doh/health/health-topics/bedbugs-information-for-landlords-and-building-managers.page#:%7E:text=New%20York%20City%20lists%20bedbugs,units%20from%20getting%20infested%20again.">report bed bug infestations</a> to prospective tenants. Since 2017, landlords must report all units that have bed bug infestations both to the local authorities and any residents sharing the same building as the infestation. </p>
<p>The future for bed bugs is unclear. Those we see today <a href="https://parasitesandvectors.biomedcentral.com/articles/10.1186/s13071-017-2232-3">are resistant</a> to most pesticides, are <a href="https://www.terminix.com/bed-bugs/behavior/where-do-bed-bugs-live/#:%7E:text=Due%20to%20their%20small%20size,aid%20of%20a%20credit%20card.">masters of subterfuge</a>, and are not going anywhere. They have <a href="https://www.sciencedirect.com/science/article/pii/S0960982219304804">co-evolved with humans</a> – so our best option for reducing their impact on our lives is for researchers and pest control professionals to spend less time trying to kill them, and more time trying to understand how they function within our world. Maybe then, we will work out a way to limit or even remove them from our homes for good.</p><img src="https://counter.theconversation.com/content/216029/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>William Hentley is affiliated with the University of Sheffield. He receives funding from the University of Sheffield.</span></em></p>The trouble is most countries don’t make bed bug infestation data available to researchers.William Hentley, Teaching Associate in Ecology, University of SheffieldLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2128502023-09-06T06:10:34Z2023-09-06T06:10:34ZAustralia’s least wanted – 8 alien species and diseases we must keep out of our island home<figure><img src="https://images.theconversation.com/files/546390/original/file-20230905-17-lal73z.jpg?ixlib=rb-1.1.0&rect=48%2C64%2C5343%2C3758&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Solenopsis_invicta1.jpg">Alexander Wild/Wikimedia Commons</a></span></figcaption></figure><p>This week’s landmark report on the impact of <a href="https://www.ipbes.net/ias">invasive alien species</a> revealed costs to the global economy exceeded US$423 billion (A$654 billion) a year in 2019. Costs have at least <a href="https://www.ipbes.net/IASmediarelease#:%7E:text=Approved%20on%20Saturday%20in%20Bonn,%24423%20billion%20annually%20in%202019%2C">quadrupled</a> every decade since 1970 and that trend is set to continue. </p>
<p>Prevention is better than a cure. Stopping pests and diseases arriving and establishing in Australia is not only better for the environment, it’s much <a href="https://cebra.unimelb.edu.au/__data/assets/pdf_file/0020/3535013/CEBRA_Value_Docs_KeyResultSummary_v0.6_Endorsed.pdf">cheaper</a> too. </p>
<p>The biosecurity system is our front line against invasion. Species that pose a significant <a href="https://www.igb.gov.au/sites/default/files/documents/environmental-biosecurity-risk_2.pdf">risk to agriculture</a> have historically received more attention, but we also need to defend our borders against threats to nature. </p>
<p>Here we take a closer look at some pests and diseases we need to keep out at all costs, to protect our biodiversity.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546391/original/file-20230905-15-598vx2.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A graph showing how the cost of managing an invasive alien species gets much larger once it is established." src="https://images.theconversation.com/files/546391/original/file-20230905-15-598vx2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546391/original/file-20230905-15-598vx2.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=374&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546391/original/file-20230905-15-598vx2.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=374&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546391/original/file-20230905-15-598vx2.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=374&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546391/original/file-20230905-15-598vx2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=470&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546391/original/file-20230905-15-598vx2.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=470&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546391/original/file-20230905-15-598vx2.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=470&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The invasion curve shows the cost of managing an incursion at various stages. Prevention is much cheaper than dealing with invaders after they arrive, and early eradication is much cheaper than longer-term containment or control.</span>
<span class="attribution"><span class="source">Invasive Species Council</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-true-damage-of-invasive-alien-species-was-just-revealed-in-a-landmark-report-heres-how-we-must-act-211893">The true damage of invasive alien species was just revealed in a landmark report. Here's how we must act</a>
</strong>
</em>
</p>
<hr>
<h2>One of the biggest threats to biodiversity</h2>
<p>Alien species are those deliberately or accidentally introduced to areas where they are not native. If they cause problems, we call them invasive.</p>
<p>Invasive alien species include weeds, feral animals, exotic pests and diseases. </p>
<p>Those that have already arrived have taken a huge toll. Introduced predators were largely responsible for most of <a href="https://www.sciencedirect.com/science/article/pii/S000632071930895X">Australia’s mammal extinctions</a>. And introduced diseases have decimated <a href="https://theconversation.com/we-name-the-26-australian-frogs-at-greatest-risk-of-extinction-by-2040-and-how-to-save-them-166339">our frogs</a>.</p>
<p>Invasive species are pushing <a href="https://www.publish.csiro.au/PC/PC18024">most (82%)</a> of Australia’s 1,914 nationally listed threatened species closer to extinction. </p>
<p>Imagine if those invasive species had been kept out of Australia. Here are eight of the <a href="https://www.agriculture.gov.au/biosecurity-trade/policy/environmental/priority-list">pests and diseases</a> we really need to keep out. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/1-7-million-foxes-300-million-native-animals-killed-every-year-now-we-know-the-damage-foxes-wreak-177832">1.7 million foxes, 300 million native animals killed every year: now we know the damage foxes wreak</a>
</strong>
</em>
</p>
<hr>
<h2>1. Giant African land snail</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546378/original/file-20230905-29-vftj6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A very large brown snail on a hand" src="https://images.theconversation.com/files/546378/original/file-20230905-29-vftj6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546378/original/file-20230905-29-vftj6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546378/original/file-20230905-29-vftj6j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546378/original/file-20230905-29-vftj6j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546378/original/file-20230905-29-vftj6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546378/original/file-20230905-29-vftj6j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546378/original/file-20230905-29-vftj6j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A giant African snail in Hong Kong, where it is invasive.</span>
<span class="attribution"><span class="source">Thomas Brown/Wikimedia Commons</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p><a href="https://www.publish.csiro.au/PC/PC18024">Giant African snails</a> have a ferocious appetite. They feed on more than 500 species of plants including agricultural crops and eucalyptus trees. The shells of these giants can be 20cm long and females typically lay 1,200 eggs a year. Adult snails could sneak into shipping containers or machinery and their eggs could be transported in soil or goods. They are now present on Christmas Island. </p>
<h2>2. Avian influenza</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546379/original/file-20230905-23-cno6xu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Faces of two pelicans close up, showing their red gullets." src="https://images.theconversation.com/files/546379/original/file-20230905-23-cno6xu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546379/original/file-20230905-23-cno6xu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546379/original/file-20230905-23-cno6xu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546379/original/file-20230905-23-cno6xu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546379/original/file-20230905-23-cno6xu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546379/original/file-20230905-23-cno6xu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546379/original/file-20230905-23-cno6xu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Thousands of Dalmatian pelicans were killed by highly pathenogenic Avian influenza in Europe in 2022.</span>
<span class="attribution"><span class="source">Birger Strahl/Unsplash</span></span>
</figcaption>
</figure>
<p><a href="https://www.agriculture.gov.au/biosecurity-trade/pests-diseases-weeds/animal/avian-influenza#what-is-avian-influenza">Avian influenza</a> or bird-flu is a viral disease found in birds. Some strains can kill farmed poultry and <a href="https://wildlifehealthaustralia.com.au/Portals/0/Documents/FactSheets/Avian/Avian_Influenza_in_Wild_Birds_in_Australia.pdf">susceptible wild birds</a>. Such highly pathogenic strains are thought to have killed millions of wild birds globally in the past few years. The virus can also jump across to mammals, recently knocking off <a href="https://www.nhm.ac.uk/discover/news/2023/march/bird-flu-kills-thousands-south-american-sea-lions-outbreak-continues.html">3,500 sea lions Peru</a>.</p>
<p>Migratory birds could bring the virus here but it could also be carried in imported birds and poultry products, including contaminated eggs, feathers, poultry feed and equipment. Our biosecurity system is responsible for <a href="https://wildlifehealthaustralia.com.au/ProgramsProjects/WildBirdSurveillance.aspx">surveillance</a> and early detection, preparedness and management to protect our vulnerable wildlife. In California, preparation includes <a href="https://www.aphis.usda.gov/aphis/newsroom/stakeholder-info/SA_By_Date/SA-2023/ca-condor-hpai">vaccinating</a> endangered condors.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/migrating-birds-could-bring-lethal-avian-flu-to-australias-vulnerable-birds-204793">Migrating birds could bring lethal avian flu to Australia's vulnerable birds</a>
</strong>
</em>
</p>
<hr>
<h2>3. New tramp ants</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546383/original/file-20230905-17-non40r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close up of an ant's head" src="https://images.theconversation.com/files/546383/original/file-20230905-17-non40r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546383/original/file-20230905-17-non40r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=426&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546383/original/file-20230905-17-non40r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=426&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546383/original/file-20230905-17-non40r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=426&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546383/original/file-20230905-17-non40r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=535&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546383/original/file-20230905-17-non40r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=535&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546383/original/file-20230905-17-non40r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=535&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A red imported fire ant in the US.</span>
<span class="attribution"><span class="source">Alexander Wild/Wikimedia Commons</span></span>
</figcaption>
</figure>
<p>We’re already battling some species of <a href="https://www.dcceew.gov.au/environment/invasive-species/insects-and-other-invertebrates/tramp-ants#:%7E:text=Key%20threatening%20processes&text=Loss%20of%20biodiversity%20and%20ecosystem,%2C%20Solenopsis%20invicta%20(fire%20ant)">tramp ants</a>, but there’s more where that came from - there are at least 16 different species. So far six species including <a href="https://www.outbreak.gov.au/current-outbreaks/red-imported-fire-ant">red imported fire ants</a> have been detected, with efforts underway to contain or eradicate them at their incursion points. On Christmas Island, another tramp ant species (<a href="https://www.dcceew.gov.au/sites/default/files/env/resources/898583db-b929-491a-8448-73fb652bca66/files/brochure-detail-crazy-ant-control-options.pdf">yellow crazy ants</a>) formed “super colonies”, killing every animal in their path, including tens of millions of the island’s iconic red and robber crabs. Ants are easily transported to new areas in dirt, plants and cargo. Tramp ants threaten Australian ecosystems, agriculture and human health. </p>
<h2>4. Bat white nose syndrome</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546385/original/file-20230905-21-y5cwgk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A small bat hanging from a cave roof with a white face" src="https://images.theconversation.com/files/546385/original/file-20230905-21-y5cwgk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546385/original/file-20230905-21-y5cwgk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546385/original/file-20230905-21-y5cwgk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546385/original/file-20230905-21-y5cwgk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546385/original/file-20230905-21-y5cwgk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546385/original/file-20230905-21-y5cwgk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546385/original/file-20230905-21-y5cwgk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A little brown bat displaying white nose syndrome in the US.</span>
<span class="attribution"><span class="source">Moriarty Marvin/USFWS/WikimediaCommons</span></span>
</figcaption>
</figure>
<p><a href="https://www.agriculture.gov.au/biosecurity-trade/pests-diseases-weeds/animal/white-nose-syndrome#:%7E:text=Australia%20is%20free%20of%20WNS,causing%20fungus%20could%20enter%20Australia.">White nose syndrome</a> is a bat disease caused by a fungus. In less than 20 years it has killed more than five million bats across North America, causing local extinctions and reducing the beneficial services performed by bats such as eating harmful insects. The fungus could be introduced to Australian caves on the shoes, clothing and equipment of people who had previously visited caves in Europe or North America. </p>
<h2>5. Crayfish plague</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546386/original/file-20230905-23-6joum6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A small crayfish in an aquarium" src="https://images.theconversation.com/files/546386/original/file-20230905-23-6joum6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546386/original/file-20230905-23-6joum6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546386/original/file-20230905-23-6joum6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546386/original/file-20230905-23-6joum6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546386/original/file-20230905-23-6joum6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546386/original/file-20230905-23-6joum6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546386/original/file-20230905-23-6joum6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Dwarf Cajun crayfish can be carriers of crayfish plague.</span>
<span class="attribution"><span class="source">Chris Lukhaup/USDA-FS/Wikimedia Commons</span></span>
</figcaption>
</figure>
<p>A highly infectious fungal disease, <a href="https://www.agriculture.gov.au/sites/default/files/sitecollectiondocuments/animal/ahl/ANZSDP-Crayfish-plague.pdf">crayfish plague</a> is the main cause of crayfish declines across Europe. It has the potential to devastate Australian freshwater crayfish populations. North American crayfish can be carriers of the disease and the illegal trade of crayfish, such as the dwarf Cajun crayfish for aquariums, also threatens to introduce the disease. </p>
<h2>6. New myrtle rust strains</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546387/original/file-20230905-25-j3j5if.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Leaves covered in a yellow powdery bloom." src="https://images.theconversation.com/files/546387/original/file-20230905-25-j3j5if.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546387/original/file-20230905-25-j3j5if.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546387/original/file-20230905-25-j3j5if.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546387/original/file-20230905-25-j3j5if.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546387/original/file-20230905-25-j3j5if.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546387/original/file-20230905-25-j3j5if.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546387/original/file-20230905-25-j3j5if.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The plant disease myrtle rust killing native rose apple leaves in Hawaii.</span>
<span class="attribution"><span class="source">Pest Plants and Animals/Wikimedia Commons</span></span>
</figcaption>
</figure>
<p>When a strain of myrtle rust arrived in Australia in 2010, it spread quickly along the east coast, <a href="https://www.nespthreatenedspecies.edu.au/media/njzno05b/1-4-3-imminent-extinction-of-australian-myrtaceae-trees-and-shrubs-by-myrtle-rust-findings-factsheet_v5.pdf">infecting 358</a> different native plant species including eucalypts, bottle brushes and lilly pillies. It has caused major declines and local extinctions of many species. Other <a href="https://www.agriculture.gov.au/biosecurity-trade/pests-diseases-weeds/plant/myrtle-rust#:%7E:text=Myrtle%20rust%20(exotic%20strains)%20is,damaging%20to%20our%20eucalyptus%20trees.">exotic myrtle rust strains</a> occur outside Australia. These present serious threats to Australia’s natural environment and to commercial native forest plantations. Importing infected plant material is the main risk of introduction. </p>
<h2>7. Savannah cats</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546388/original/file-20230905-15-sjem6n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close up of a patterned black and tan cat with large pointy ears." src="https://images.theconversation.com/files/546388/original/file-20230905-15-sjem6n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546388/original/file-20230905-15-sjem6n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546388/original/file-20230905-15-sjem6n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546388/original/file-20230905-15-sjem6n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546388/original/file-20230905-15-sjem6n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546388/original/file-20230905-15-sjem6n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546388/original/file-20230905-15-sjem6n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Savannah cats are bred by crossing a domestic cat with an African serval.</span>
<span class="attribution"><span class="source">Jason Douglas/Wikimedia Commons</span></span>
</figcaption>
</figure>
<p><a href="https://www.nespthreatenedspecies.edu.au/news-and-media/media-releases/banning-savannah-cats-in-australia-was-good-science">Savannah cats</a> are two to three times the size of domestic cats. In 2008 the federal government banned the importation of savannah cats. A <a href="https://www.mdpi.com/2076-2615/9/10/795">scientific assessment</a> found pet savannah cats had the potential to establish and roam across 97% of the country if they escaped or were released. They can take down prey twice as large as feral cats, so 90% of Australia’s native land mammals would be at risk. Demand for the species from the pet trade raises the risk of smuggling or illegal trade.</p>
<h2>8. Black spined toad</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546389/original/file-20230905-24-tyy3v6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A brown toad with black markings on dried orange leaves." src="https://images.theconversation.com/files/546389/original/file-20230905-24-tyy3v6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546389/original/file-20230905-24-tyy3v6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=429&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546389/original/file-20230905-24-tyy3v6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=429&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546389/original/file-20230905-24-tyy3v6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=429&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546389/original/file-20230905-24-tyy3v6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=539&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546389/original/file-20230905-24-tyy3v6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=539&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546389/original/file-20230905-24-tyy3v6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=539&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A black spined toad in Taiwan.</span>
<span class="attribution"><span class="source">LiCheng Shih/Wikimedia Commons</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
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<p>The <a href="https://www.agriculture.gov.au/biosecurity-trade/import/arrival/pests/black-spined-toad">black spined toad</a> is potentially more damaging than the cane toad because it could survive across a bigger region including in the colder parts of Australia. It would prey on native frogs and other small animals, be toxic to larger animals, and probably carry exotic parasites or disease. It is a common stowaway in shipping cargo. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/97-of-australians-want-more-action-to-stop-extinctions-and-72-want-extra-spending-on-the-environment-207811">97% of Australians want more action to stop extinctions and 72% want extra spending on the environment</a>
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<h2>Prioritising nature</h2>
<p>Australia’s biosecurity system has generally served our country well, but it is under constant and <a href="https://www.igb.gov.au/sites/default/files/documents/environmental-biosecurity-risk_2.pdf">growing strain</a>. Historically, the environment has also been the <a href="https://www.aph.gov.au/Parliamentary_Business/Committees/Senate/Environment_and_Communications/biosecurity/Report/c03">poor cousin of agriculture</a> at the biosecurity table.</p>
<p>Preparedness and responses for environmental threats remain <a href="https://www.mdpi.com/1999-4907/10/4/336">chronically underfunded</a>, especially when compared to those developed for industry.</p>
<p>A well-resourced independent body focused on the prevention and early elimination of new environmental pests and diseases would be a major step toward achieving our <a href="https://www.dcceew.gov.au/sites/default/files/documents/threatened-species-action-plan-2022-2032.pdf">global commitments</a> to end extinction.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/hear-me-out-we-could-use-the-varroa-mite-to-wipe-out-feral-honey-bees-and-help-australias-environment-185959">Hear me out – we could use the varroa mite to wipe out feral honey bees, and help Australia's environment</a>
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</p>
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<img src="https://counter.theconversation.com/content/212850/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jaana Dielenberg is based at The University of Melbourne and works for the Biodiversity Council. She is a member of Invertebrates Australia and the Ecological Society of Australia. She previously worked for the now ended Threatened Species Recovery Hub of the Australian Government's National Environmental Science Program. She thanks James Trezise for his contribution to this article. </span></em></p><p class="fine-print"><em><span>Patrick O'Connor receives funding from the Australian Research Council and Australian and State Governments. He is a councilor on the Biodiversity Council and affiliated with the Nature Conservation Society of South Australia and the Australian Landcare movement. </span></em></p>Australia’s biosecurity system is on high alert for alien invaders. Here’s a hit list of eight baddies we believe pose the greatest threat to Australia’s biodiversity.Jaana Dielenberg, University Fellow, Charles Darwin UniversityPatrick O'Connor, Associate Professor, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2118932023-09-04T12:01:47Z2023-09-04T12:01:47ZThe true damage of invasive alien species was just revealed in a landmark report. Here’s how we must act<figure><img src="https://images.theconversation.com/files/546132/original/file-20230904-17-cgmyf9.jpg?ixlib=rb-1.1.0&rect=53%2C53%2C3932%2C2181&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/aerial-top-view-container-cargo-ship-708817909">Avigator Fortuner. Shutterstock</a></span></figcaption></figure><p>Invasive alien species are driving biodiversity loss and extinctions in every country, all over the world. </p>
<p>Responding to the challenge, the United Nations is today releasing the <a href="https://doi.org/10.5281/zenodo.7430692">first global assessment</a> of invasive alien species and their control. </p>
<p>It comes from the <a href="https://www.ipbes.net">Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services</a> (IPBES), which represents almost 140 member states. </p>
<p>Over four years, 86 expert authors from 49 countries gathered the latest scientific evidence and Indigenous and local knowledge on invasive alien species. The report draws on more than 13,000 references, including governmental reports. We were among the authors. Here are some of the key insights for Australia and Aotearoa New Zealand. </p>
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<p>
<em>
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Read more:
<a href="https://theconversation.com/invasive-species-are-australias-number-one-extinction-threat-116809">Invasive species are Australia's number-one extinction threat</a>
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<h2>Hope in the face of increasing threats</h2>
<p>In 2019, IPBES released a <a href="https://www.ipbes.net/global-assessment">global biodiversity assessment</a> that placed invasive alien species in the top five drivers of biodiversity loss - alongside changing land- and sea-use, over-exploitation of natural resources, climate change, and pollution. </p>
<p>This triggered further assessment to determine the current global state of biological invasions, the effectiveness of our existing responses, and recommended management and policy options. </p>
<p>The result, released today, is the most comprehensive overarching policy-relevant report on biological invasions to date. </p>
<p>It promises to help us meet our international obligations under the recently adopted UN <a href="https://www.cbd.int/">Convention on Biological Diversity</a>. In particular, one of the targets in the Kunming-Montreal <a href="https://www.cbd.int/article/cop15-final-text-kunming-montreal-gbf-221222">Global Biodiversity Framework</a> is to “eliminate, minimise, reduce and/or mitigate the impacts of invasive alien species on biodiversity and ecosystem services”.</p>
<p>The world faces increasing biosecurity threats, but effective management can prevent or lessen the extent of subsequent biological invasions. Ambitious progress can be achieved with an integrated approach.</p>
<h2>The experience in Australia and Aotearoa New Zealand</h2>
<p>Australia already has close to <a href="https://www.gbif.org/dataset/15147db1-27c3-49b5-9c69-c78d55a4b8ff">3,000</a> introduced alien species. Aotearoa New Zealand has almost <a href="https://www.gbif.org/dataset/b286f8ee-1e29-4f8a-a041-9106bb1796f3">900</a>.</p>
<p>Globally, we observe around 200 new alien species every year, and many of these species (>10%) have negative impacts, including threats to native species, the health of natural vegetation, or the way ecosystems work. </p>
<p>Australian examples include <a href="https://theconversation.com/1-7-million-foxes-300-million-native-animals-killed-every-year-now-we-know-the-damage-foxes-wreak-177832">foxes</a>, <a href="https://theconversation.com/why-red-fire-ants-and-yellow-crazy-ants-have-given-themselves-a-green-light-to-invade-australia-208479">red imported fire ants</a> and <a href="https://theconversation.com/field-of-nightmares-gamba-grass-in-the-top-end-12178">gamba grass</a>. </p>
<p>Aotearoa New Zealand suffers from invasive Australian <a href="https://www.doc.govt.nz/nature/pests-and-threats/animal-pests/possums/">possums</a>. And the Māori cultural icon the Kauri tree is under siege from a deadly <a href="https://theconversation.com/lord-of-the-forest-new-zealands-most-sacred-tree-is-under-threat-from-disease-but-response-is-slow-100447">dieback disease</a>.</p>
<p>The assessment reveals that invasive alien species have contributed to 60% of global extinctions, and have been the sole driver of 16% of recorded extinctions. </p>
<p><a href="https://theconversation.com/invasive-species-are-australias-number-one-extinction-threat-116809">Australia</a> and <a href="https://www.doc.govt.nz/nature/pests-and-threats/predator-free-2050/">Aotearoa New Zealand</a> have among the highest modern global native species extinction rates. Australia is the worst in the world <a href="https://theconversation.com/gut-wrenching-and-infuriating-why-australia-is-the-world-leader-in-mammal-extinctions-and-what-to-do-about-it-192173">for mammals</a>, while Aotearoa New Zealand has experienced tragic loss in <a href="https://theconversation.com/call-of-the-huia-how-nzs-bird-of-the-century-contest-helps-us-express-ecological-grief-210698">endemic birds</a>, largely due to invasive species. </p>
<p>The economies of both countries rely heavily on agriculture, trade and eco-tourism. These sectors are highly susceptible to threats from invasive alien species. The cost to Australia is <a href="https://theconversation.com/pest-plants-and-animals-cost-australia-around-25-billion-a-year-and-it-will-get-worse-164969">A$24.5 billion a year</a> out of an estimated global cost of $654 billion (<a href="https://doi.org/10.5281/zenodo.7430692">US$423 billion a year</a>). </p>
<p>The cost of biological invasions is quadrupling every decade, but stringent biosecurity policies and practices can protect our environment and economies. They also safeguard our wellbeing and cultural and social livelihoods. </p>
<p>Continued cooperation and investment across our region is paramount to preventing future impacts from increasing threats. These include <a href="https://theconversation.com/to-lock-out-foot-and-mouth-disease-australia-must-help-our-neighbour-countries-bolster-their-biosecurity-188010">foot and mouth disease</a> and <a href="https://theconversation.com/avian-influenza-how-bird-flu-affects-domestic-and-wild-flocks-and-why-a-one-health-approach-matters-182497">avian influenza</a>. </p>
<p>At the same time, already established invasive alien species can supercharge environmental disasters. For example, the wildfire-promoting properties of introduced <a href="https://theconversation.com/feed-or-weed-new-pastures-are-sowing-problems-for-the-future-33733">African pasture grasses</a> exacerbated <a href="https://time.com/6305735/invasive-plants-from-colonists-fueled-maui-wildfires">bushfires in Hawaii</a> this year. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/new-expose-of-australias-exotic-pet-trade-shows-an-alarming-proliferation-of-alien-threatened-and-illegal-species-203354">New exposé of Australia's exotic pet trade shows an alarming proliferation of alien, threatened and illegal species</a>
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<h2>Coordinate, consult and prioritise</h2>
<p>An effective biosecurity system can mitigate the threats from invasive species. But to do so, we’ll need coherent policy across primary production and logistic sectors, better education and greater public awareness.</p>
<p>We need to coordinate and prioritise our efforts, from offshore ports to border control and quarantine, through to eradication or containment of any new pests and weeds.</p>
<p>Government-industry partnerships are leading to trusted “green-lane” trade supply chains. This cuts red tape for businesses that manage import risks and produce pre-costed and co-designed emergency response agreements.</p>
<p>Prevention will not stop arrivals altogether. We will still have to contend with blow-ins on storm winds, <a href="https://theconversation.com/debris-from-the-2011-tsunami-carried-hundreds-of-species-across-the-pacific-ocean-84773">ocean waves</a> and boat hulls. There’s also the $23 billion a year <a href="https://theconversation.com/alien-invaders-the-illegal-reptile-trade-is-a-serious-threat-to-australia-68815">illegal pet trade</a>.</p>
<p>Biosecurity tools work best alongside strong public support, regulation and governance. We share a proud history of effective biological control programs for many <a href="https://theconversation.com/explainer-how-biocontrol-fights-invasive-species-31298">weeds and pests</a>. Australia’s approach to <a href="https://theconversation.com/releasing-a-virus-against-rabbits-is-effective-but-can-make-them-immune-if-let-loose-at-the-wrong-time-176028">rabbit control using a virus</a> was a world-first and it remains in use 70 years later. This has delivered benefits worth more than <a href="https://www.csiro.au/en/research/natural-environment/biodiversity/fighting-plagues-and-predators">$70 billion</a>. </p>
<p>Despite strong biosecurity measures, highly engaged primary industries agricultural industries, excellent research infrastructure and a high level of public awareness, invasive alien species continue to <a href="https://theconversation.com/new-zealand-needs-to-up-its-biosecurity-game-to-protect-the-country-from-the-next-devastating-pest-threat-207104">slip through our borders</a> and multiply. </p>
<p>We tried to defend our countries against recent invasions from the <a href="https://theconversation.com/the-fall-armyworm-invasion-is-fierce-this-year-and-scientists-are-researching-how-to-stop-its-destruction-of-lawns-football-fields-and-crops-167098">fall armyworm</a>, <a href="https://theconversation.com/what-is-myrtle-rust-and-why-has-this-disease-closed-lord-howe-island-to-visitors-202045">myrtle rust</a> and the <a href="https://theconversation.com/australia-is-in-a-unique-position-to-eliminate-the-bee-killing-varroa-mite-heres-what-happens-if-we-dont-205926">varroa mite</a>. But they have still managed to establish. </p>
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<h2>One world, ‘One Biosecurity’</h2>
<p>The rising pressure of trade will likely outpace the resourcing dedicated to biosecurity measures. Frequent interceptions of pests, weeds, and diseases at our border highlight the pressure we are under. We will have to simply become smarter, more effective, and better coordinated across the <a href="https://www.nzherald.co.nz/the-listener/new-zealand/the-new-billion-dollar-biosecurity-threats-at-our-borders/F6AQFEQCE5GUZDMSJM6B5ZSMUI/">human, animal, plant and ecosystem health sectors</a>. </p>
<p>We encourage governments to recognise the threats invasive alien pests pose and mobilise their resources and capability to combat these threats – in regions where a species is first recognised as going rogue, rather than simply monitoring its progressive global spread. This is the <a href="https://www.nzherald.co.nz/the-country/news/covid-19-coronavirus-expert-calls-for-holistic-approach-to-biosecurity/WOWPH22RSVCHIE5D3NDXL6ZZII/">One Biosecurity concept</a>. </p>
<p>Australia and Aotearoa New Zealand can play a much stronger leadership role in <a href="https://www.cookislandsnews.com/internal/national/regional/environment/economy/pacific-islands/pacific-island-countries-meet-in-rarotonga-to-discuss-biosecurity-and-trade/">managing biosecurity risks in the Pacific</a>. After all, lax border protocols in our neighbourhood help pests and diseases end up on our doorstep. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-red-fire-ants-and-yellow-crazy-ants-have-given-themselves-a-green-light-to-invade-australia-208479">Why red fire ants and yellow crazy ants have given themselves a green light to invade Australia</a>
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<img src="https://counter.theconversation.com/content/211893/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andy Sheppard, as a chief research scientist with CSIRO, receives funding from the Australian federal government. This included funding to participate in the IPBES Assessment process as a coordinating lead author from 2019-2023, where he co-led Chapter 5 and made contributions to three other chapters. He is therefore well connected to the IPBES process, corporate, assessment team and media team. However, as a CSIRO employee he respects all the values of the organisation and does not undertake any commentary that would be seen to criticise Australian government policy or in any way lobby for additional research funding from governments. </span></em></p><p class="fine-print"><em><span>Melodie McGeoch receives funding from the Australian Research Council - ARC SRIEAS Grant SR200100005 Securing Antarctica’s Environmental Future. She is affiliated with La Trobe University and Monash University. She is 1st Vice Chair of the Science Committee of the Global Biodiversity Information Facility, Fellow of the African Academy of Sciences, Member of the Implementation Committee of the Group on Earth Observations Biodiversity Observation Network, Independent Board Member of the National Computation Infrastructure and on the Editorial Board of Global Ecology and Biogeography.</span></em></p><p class="fine-print"><em><span>Philip Hulme receives research funding from the New Zealand government. He is affiliated with Lincoln University, New Zealand. and is a member of the Canterbury-Aoraki Conservation Board and a Director of the QEII Trust. He is a member of the Biosecurity Advisory Groups of both Environment Canterbury and Zespri.</span></em></p><p class="fine-print"><em><span>Phill Cassey receives funding from the Centre for Invasive Species Solutions and the Australian Research Council. </span></em></p>Alien invaders are penetrating the borders of every country in the world. Now the full extent of the problems and potential solutions have been exposed, in a new United Nations report.Andy Sheppard, Research Director CSIRO Health & Biosecurity, CSIROMelodie McGeoch, Professor, La Trobe UniversityPhilip Hulme, Distinguished Professor in Pest Management and Conservation, Lincoln University, New ZealandPhill Cassey, Australian Research Council Industry Laureate Fellow, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2010662023-04-17T21:43:23Z2023-04-17T21:43:23ZStudying the stomach contents of spiders shows how they help control crop pests<figure><img src="https://images.theconversation.com/files/517678/original/file-20230327-24-4hh6yn.jpg?ixlib=rb-1.1.0&rect=0%2C27%2C4608%2C3035&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Spiders can be effective pest control agents.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/studying-the-stomach-contents-of-spiders-shows-how-they-help-control-crop-pests" width="100%" height="400"></iframe>
<p>On farms, spiders are important predators who control insect populations, including pests that can damage crops. </p>
<p>Understanding their role in agricultural ecosystems reveals how they could be used as a <a href="https://www.nj.gov/agriculture/divisions/pi/prog/buglab/what-is-biological-control/#:%7E:text=">biocontrol agent</a> to limit pest populations.</p>
<p>The semi-natural areas that surround farm fields are <a href="https://doi.org/10.1111/rec.13485">important sites for spiders</a> and other arthropods. These habitats can provide shelter and alternative food sources for spiders when crop fields might be too harsh to live in because of pesticide use or tilling.</p>
<h2>Spiders’ diet</h2>
<p>To determine whether spiders are effective at biocontrol, it is crucial to know the diet of these spiders and whether they eat crop pests.</p>
<p>The relative size of some insect prey, and the toughness of their exoskeleton, limit spiders’ ability to mechanically chew their food, so they eat by liquefying the remains of their prey.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/514007/original/file-20230307-22-g322r3.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="an illustration of the anatomy of a spider" src="https://images.theconversation.com/files/514007/original/file-20230307-22-g322r3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514007/original/file-20230307-22-g322r3.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=354&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514007/original/file-20230307-22-g322r3.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=354&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514007/original/file-20230307-22-g322r3.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=354&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514007/original/file-20230307-22-g322r3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=444&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514007/original/file-20230307-22-g322r3.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=444&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514007/original/file-20230307-22-g322r3.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=444&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Diagram of the internal anatomy of a female two-lunged spider.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Spider_internal_anatomy-en.svg">(J.H. Comstock and R.F. Felix)</a></span>
</figcaption>
</figure>
<p>Spiders <a href="https://doi.org/10.1186/s12864-017-3987-9">expel digestive enzymes from their intestinal tract</a> onto their prey to break down body tissues. This makes it difficult for researchers to investigate spider diets. </p>
<p>One solution is to analyze the gut contents of spiders using DNA barcoding, a technique that involves sequencing a short, standardized fragment of DNA from a particular gene to identify a species — including any liquefied evidence.</p>
<p>The history of DNA barcoding dates back two decades, when biologist Paul Hebert <a href="https://doi.org/10.1098/rspb.2002.2218">applied DNA barcoding to arthropods</a>. Hebert pointed out that animal species could be distinguished by sequencing a specimen’s DNA.</p>
<p>Over the years, this technology has become increasingly sophisticated, with advances in DNA sequencing and bioinformatics making it possible to quickly and accurately identify species from a wide range of samples.</p>
<h2>Gut contents</h2>
<p>The use of DNA barcoding specifically <a href="https://doi.org/10.1002/edn3.62">for spider gut content analysis has become increasingly popular</a>. By analyzing the DNA found in a spider’s gut, researchers can determine what the spider has eaten and learn about its role in the ecosystem. </p>
<p>The process of <a href="https://doi.org/10.1139/gen-2018-0093">spider gut content analysis using DNA barcoding</a> begins by capturing spiders in the field. Spiders are then ground up whole into a “DNA soup” using a specific set of steps to extract the DNA from the stomach contents. This grinding step is important because a spider’s stomach extends into many different parts of the body and it’s why total body grinding can <a href="https://doi.org/10.1371/journal.pone.0196589">help find results of the prey’s remains</a>.</p>
<p>Researchers can use DNA barcoding to determine if a spider is a generalist — feeding on a wide range of prey species, or a specialist — feeding on a particular species or group of species (like agricultural pests).</p>
<p>With this information, spiders could be deployed as biocontrol agents — a more sustainable, cheaper and environmentally friendly pest management solution.</p>
<p>Generalist predators, including spiders, eat <a href="https://doi.org/10.1038/s41598-018-26191-0">whatever they can find</a> in agricultural landscapes. This includes pest species like <a href="https://www.britannica.com/animal/aphid">aphids</a> and non-pests like <a href="https://theconversation.com/hidden-housemates-springtails-are-everywhere-even-in-your-home-60233">springtails</a>. </p>
<p>Researchers found that early season sampling revealed “empty guts” of predators, and an increase of gut contents later in the season. This previous research investigated only three spider species and only during the early and the late cropping season. </p>
<p>Our ongoing research is tackling these gaps.</p>
<h2>Sampling spider communities</h2>
<p>Our research is conducted in agricultural landscapes with one thing in common: they all have restored habitat adjacent to the crop field. This includes tall-grass prairie and wetland areas. </p>
<p>Different habitat types on farms will undeniably change food web structure on farms, with different prey and predator groups coming in and out throughout the season. These aquatic (wetland) and terrestrial (prairie) habitats may foster spider populations and therefore the biological control function on farms. </p>
<p>We sampled spider communities intensively for four months between May and August, and at different distances from crop fields to study spider movement throughout the crop growing season. </p>
<p>This knowledge is largely important for managing farm systems to help determine the timing of pesticide applications in crop fields.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/515973/original/file-20230317-22-znihry.jpeg?ixlib=rb-1.1.0&rect=0%2C17%2C1200%2C779&q=45&auto=format&w=1000&fit=clip"><img alt="a close-up of a tiny spider on a leaf" src="https://images.theconversation.com/files/515973/original/file-20230317-22-znihry.jpeg?ixlib=rb-1.1.0&rect=0%2C17%2C1200%2C779&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/515973/original/file-20230317-22-znihry.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/515973/original/file-20230317-22-znihry.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/515973/original/file-20230317-22-znihry.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/515973/original/file-20230317-22-znihry.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/515973/original/file-20230317-22-znihry.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/515973/original/file-20230317-22-znihry.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Jumping spiders are more active during June and August.</span>
<span class="attribution"><span class="source">(A. Dolezal)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Spider groups</h2>
<p>Our preliminary data has found several spider functional groups — web-spinning, ground spiders, ambush spiders, hunters — on farmlands with restored habitat next to crop fields. </p>
<p>A total of 20 spider families have been consistently found throughout the sampling period, with some spiders more prevalent in certain habitats than others. These 20 spider families on farms is a great number to see considering we have an <a href="https://www.toronto.ca/wp-content/uploads/2017/08/8f2a-Biodiversity_SpiderBook-Division-Planning-And-Development.pdf">estimated 25 spider families in and around these areas</a>. </p>
<p>We have been finding a higher abundance of spiders and their insect prey in the semi-natural areas (wetlands, prairies) surrounding the crop fields, and closer to the restored areas. </p>
<p>Our preliminary data also shows that June and August are peak times for spider activity on farms, and they move around a lot more than in May and July.</p>
<h2>Providing protection</h2>
<p>Gleaning information from spider stomach contents will help understand the role spiders play in the ecosystem. This is particularly important in agriculture to promote environmentally sustainable models for crop protection inspired by natural pest control.</p>
<p>According to a meta-analysis of 58 published studies, <a href="https://doi.org/10.1111/geb.12927">spiders suppressed agricultural pest insects in 79 per cent of studies</a>, which resulted in improved crop performance.</p>
<p>Relying excessively on chemicals to control crop pests is not a sustainable option; using ecologically based approaches is urgently needed. </p>
<p>DNA barcoding opens up new avenues for studying <a href="https://doi.org/10.3390/insects11050294">the ecology of spiders and their potential as biological control agents in agricultural landscapes</a>. And with further advances in DNA sequencing technologies and bioinformatics, this will contribute to agricultural practices that are more sustainable.</p><img src="https://counter.theconversation.com/content/201066/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Spiders liquefy their prey in order to consume it, and this makes it challenging to determine what spiders eat. A new approach that uses DNA barcoding is helping researchers figure out spider diets.Aleksandra Jessica Dolezal, PhD Candidate, Integrative Biology, University of GuelphAndrew MacDougall, Professor, Integrative Biology, University of GuelphDirk Steinke, Adjunct Professor, Integrative Biology, University of GuelphJeremy deWaard, Adjunct Professor, Centre for Biodiversity Genomics, University of GuelphLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1889392022-11-15T13:22:40Z2022-11-15T13:22:40ZAnts – with their wise farming practices and efficient navigation techniques – could inspire solutions for some human problems<figure><img src="https://images.theconversation.com/files/494699/original/file-20221110-21-p2hi2g.jpg?ixlib=rb-1.1.0&rect=10%2C0%2C2235%2C1329&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Leafcutter ants cultivate fungus gardens that feed sprawling colonies.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/three-leafcutter-ants-carrying-leaves-close-up-royalty-free-image/200187319-004">Tim Flach/Stone via Getty Images</a></span></figcaption></figure><p>King Solomon may have gained some of his famed wisdom from an unlikely source – ants.</p>
<p>According to a <a href="https://www.jewishencyclopedia.com/articles/13842-solomon#anchor14">Jewish legend</a>, Solomon conversed with a clever ant queen that confronted his pride, making quite an impression on the Israelite king. In the biblical book of <a href="https://www.biblegateway.com/passage/?search=Proverbs%206%3A6-8&version=KJV">Proverbs (6:6-8)</a>, Solomon shares this advice with his son: “Look to the ant, thou sluggard, consider her ways and be wise. Which having no guide, overseer, or ruler, provideth her meat in the summer, and gathereth her food in the harvest.”</p>
<p>While I can’t claim any familial connection to King Solomon, despite sharing his name, I’ve long admired the wisdom of ants and have spent over 20 years <a href="https://scholar.google.com/citations?user=bnXkcNUAAAAJ&hl=en&oi=sra">studying their ecology, evolution and behaviors</a>. While the notion that ants may offer lessons for humans has certainly been around for a while, there may be new wisdom to gain from what scientists have learned about their biology.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/vG-QZOTc5_Q?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Ants have evolved highly complex social organizations.</span></figcaption>
</figure>
<h2>Lessons from ant agriculture</h2>
<p>As a researcher, I’m especially intrigued by <a href="https://doi.org/10.1093/isd/ixab029">fungus-growing ants</a>, a group of 248 species that cultivate fungi as their main source of food. They include 79 species of <a href="https://wwnorton.com/books/9780393338683">leafcutter ants</a>, which grow their fungal gardens with freshly cut leaves they carry into their enormous underground nests. I’ve excavated hundreds of leafcutter ant nests from Texas to Argentina as part of the scientific effort to understand how these ants coevolved with their fungal crops.</p>
<p>Much like human farmers, each species of fungus-growing ant is very particular about the type of crops they cultivate. Most varieties descend from a type of fungus that the ancestors of fungus-growing ants began growing <a href="https://doi.org/10.1093/isd/ixab029">some 55 million to 65 million years ago</a>. Some of these fungi became domesticated and are now unable to survive on their own without their insect farmers, much like some human crops such as maize.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/-XuPtW8lBCM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Ants started farming tens of millions of years before humans.</span></figcaption>
</figure>
<p>Ant farmers face many of the same challenges human farmers do, including the threat of pests. A parasite called <a href="https://doi.org/10.1186/s43008-021-00078-8"><em>Escovopsis</em></a> can devastate ant gardens, causing the ants to starve. Likewise in human agriculture, pest outbreaks have contributed to disasters like the <a href="https://evolution.berkeley.edu/the-relevance-of-evolution/agriculture/monoculture-and-the-irish-potato-famine-cases-of-missing-genetic-variation/">Irish Potato Famine</a>, the 1970 <a href="https://doi.org/10.1126/science.171.3976.1113">corn blight</a> and the <a href="https://theconversation.com/with-the-familiar-cavendish-banana-in-danger-can-science-help-it-survive-64206">current threat to bananas</a>.</p>
<p>Since the 1950s, human agriculture has become industrialized and relies on <a href="https://www.birmingham.ac.uk/research/quest/preserving-and-creating-culture/a-global-history-of-monoculture.aspx">monoculture</a>, or growing large amounts of the same variety of crop in a single place. Yet monoculture makes crops more vulnerable to pests because it is easier to destroy an entire field of genetically identical plants than a more diverse one.</p>
<p>Industrial agriculture has looked to chemical pesticides as a partial solution, turning agricultural pest management into a <a href="https://www.alliedmarketresearch.com/pest-control-market">billion-dollar industry</a>. The trouble with this approach is that pests can <a href="https://islandpress.org/books/chasing-red-queen">evolve new ways to get around pesticides</a> faster than researchers can develop more effective chemicals. It’s an arms race – and the pests have the upper hand.</p>
<p>Ants also <a href="https://mitpress.mit.edu/9780262543200/the-convergent-evolution-of-agriculture-in-humans-and-insects/">grow their crops in monoculture</a> and at a similar scale – after all, a leafcutter ant nest can be home to <a href="https://wwnorton.com/books/9780393338683">5 million ants</a>, all of which feed on the fungi in their underground gardens. They, too, use a pesticide to control <em>Escovopsis</em> and other pests. </p>
<p>Yet, their approach to pesticide use differs from humans’ in one important way. Ant pesticides are <a href="https://doi.org/10.1021/acscentsci.0c00978">produced by bacteria</a> they allow to grow in their nests, and in some cases even on their bodies. Keeping bacteria as a living culture allows the microbes to <a href="https://doi.org/10.1128/AEM.00178-21">adapt in real time</a> to evolutionary changes in the pests. In the arms race between pests and farmers, farming ants have discovered that live bacteria can serve as pharmaceutical factories that can keep up with ever-changing pests.</p>
<p>Whereas recent developments in agricultural pest management have focused on <a href="https://entomology.ca.uky.edu/ef130">genetically engineering</a> <a href="https://www.nature.com/scitable/knowledge/library/use-and-impact-of-bt-maize-46975413/">crop plants</a> to produce their own pesticides, the lesson from 55 million years of ant agriculture is to <a href="https://doi.org/10.3389/fsoil.2022.833181">leverage living microorganisms</a> to make <a href="https://doi.org/10.1007/978-981-16-4843-4_13">useful products</a>. Researchers are currently experimenting with <a href="https://link.springer.com/book/10.1007/978-981-10-0707-1">applying live bacteria to crop plants</a> to determine if they are effective at producing pesticides that can evolve in real time along with pests.</p>
<h2>Improving transportation</h2>
<p>Ants can also offer practical lessons in the realm of transportation.</p>
<p>Ants are notoriously good at quickly locating food, whether it’s a dead insect on a forest floor or some crumbs in your kitchen. They do this by leaving a <a href="https://doi.org/10.1111/j.1365-3032.2008.00658.x">trail of pheromones</a> – chemicals with a distinctive smell ants use to guide their nest mates to food. The shortest route to a destination will accumulate the most pheromone because more ants will have traveled back and forth along it in a given amount of time.</p>
<p>In the 1990s, computer scientists developed a <a href="https://www.sciencedirect.com/topics/engineering/ant-colony-optimization">class of algorithms</a> modeled after ant behavior that are very effective at finding the shortest path between two or more locations. Like with real ants, the shortest route to a destination will accumulate the most virtual pheromone because more virtual ants will have traveled along it in a given amount of time. Engineers have used this simple but effective approach to <a href="https://doi.org/10.1016/j.mcm.2010.04.021">design telecommunication networks</a> and <a href="https://doi.org/10.1007%2F978-3-030-50146-4_25">map delivery routes</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Leafcutter ants crowding a patch of dirt" src="https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Thousands of ants can travel along the same path without causing traffic jams.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/close-up-of-plant-growing-on-field-royalty-free-image/764924521">Esteban Castao Solano/EyeEm via Getty Images</a></span>
</figcaption>
</figure>
<p>Not only are ants good at finding the shortest route from their nests to a source of food, thousands of ants are capable of traveling along these routes without causing traffic jams. I recently began collaborating with physicist <a href="https://scholar.google.com/citations?user=reX35vUAAAAJ&hl=es">Oscar Andrey Herrera-Sancho</a> to study how leafcutter ants maintain such a steady flow along their foraging paths without the slowdowns typical of crowded human sidewalks and highways.</p>
<p>We are <a href="http://solomon.rice.edu/2019/01/11/field-research-in-costa-rica/">using cameras to track</a> how each individual ant responds to artificial obstacles placed on their <a href="https://www.alexanderwild.com/Ants/Making-a-Living/The-Farming-Ants-Leafcutters/i-rWjNDhM/A">foraging trails</a>. Our hope is that by getting a better understanding of the rules ants use to respond to both obstacles and the movement of other ants, we can develop algorithms that can eventually help program self-driving cars that never get stuck in traffic.</p>
<h2>Look to the ant</h2>
<p>To be fair, there are plenty of ways ants are far from perfect role models. After all, some ant species are known for <a href="https://www.hup.harvard.edu/catalog.php?isbn=9780674241558">indiscriminate killing</a>, and others for <a href="https://theconversation.com/slave-ants-and-their-masters-are-locked-in-a-deadly-relationship-36737">enslaving babies</a>. </p>
<p>But the fact is that ants <a href="https://www.basicbooks.com/titles/mark-w-moffett/the-human-swarm/9781541617292/">remind us of ourselves</a> – or the way we might like to imagine ourselves – in many ways. They live in complex societies with <a href="https://doi.org/10.1007/s00265-015-2045-3">division of labor</a>. They <a href="https://www.simonandschuster.com/books/Ants-At-Work/Deborah-Gordon/9781451665703">cooperate to raise their young</a>. And they accomplish <a href="https://press.princeton.edu/books/hardcover/9780691179315/ant-architecture">remarkable engineering feats</a> – like building structures with air funnels that can house millions – all without blueprints or a leader. Did I mention their societies are <a href="https://www.press.jhu.edu/books/title/10551/secret-lives-ants">run entirely by females</a>?</p>
<p>There is still a lot to learn about ants. For example, researchers still don’t fully understand <a href="https://doi.org/10.1016/j.tree.2020.11.010">how an ant larva develops</a> into either a queen – a female with wings that can live for 20 years and lay millions of eggs – or a worker – a wingless, often sterile female that lives for less than a year and performs all the other jobs in the colony. What’s more, scientists are constantly discovering new species – <a href="https://www.antwiki.org/wiki/Taxa_Described_in_2021">167 new ant species</a> were described in 2021 alone, bringing the total to more than 15,980. </p>
<p>By considering ants and their many fascinating ways, there’s plenty of wisdom to be gained.</p><img src="https://counter.theconversation.com/content/188939/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Scott Solomon receives funding from the National Science Foundation and the Big Thicket Association. </span></em></p>Over hundreds of million years of evolution, ants have come up with some pretty smart solutions to problems of agriculture, navigation and architecture. People could learn a thing or two.Scott Solomon, Associate Teaching Professor of Ecology and Evolutionary Biology, Rice UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1880102022-08-11T20:04:22Z2022-08-11T20:04:22ZTo lock out foot-and-mouth disease, Australia must help our neighbour countries bolster their biosecurity<p><a href="https://theconversation.com/what-is-foot-and-mouth-disease-why-farmers-fear-apocalyptic-bonfires-of-burning-carcasses-186741">Foot-and-mouth disease</a> now poses a high threat to Australia. This highly contagious livestock virus is sweeping Indonesia – the closest it’s been to Australia <a href="https://www.agriculture.gov.au/about/news/media-releases/media-statement-foot-and-mouth-disease-detected-indonesia">since the 1980s</a>. A large outbreak here could cause decimate the livestock industry and cause <a href="https://www.agriculture.gov.au/abares/research-topics/biosecurity/biosecurity-economics/fmd-update-of-2013-estimate">A$80 billion</a> in economic damage over the coming decade.</p>
<p>The peril coincides with Australia’s first <a href="https://www.biosecurity.gov.au/about/national-biosecurity-committee/nbs">national biosecurity strategy</a> released by the federal government this week. The plan warns Australia faces “multiple risks, on multiple fronts, at the same time” and cites foot-and-mouth disease as among the emerging challenges.</p>
<p>But the foot-and-mouth outbreak in Indonesia should not come as a surprise. It’s been decades in the making – just the latest consequence of biosecurity shortcomings in the region. </p>
<p>A suite of measures are needed to prevent exotic pests and diseases entering Australia. Crucial to this is being a good neighbour: helping other countries in our region to strengthen their biosecurity efforts.</p>
<h2>Dwindling agriculture aid</h2>
<p>Foot-and-mouth disease is just one of many invasive pests and diseases to have spread internationally, including in Southeast Asia in recent years. </p>
<p>Regrettably, <a href="https://www.dpi.nsw.gov.au/biosecurity/seasonal-pests-and-diseases/spring/varroa-mite">Varroa mite</a> (which attacks honeybees) and <a href="https://www.business.qld.gov.au/industries/farms-fishing-forestry/agriculture/crop-growing/priority-pest-disease/fall-armyworm">fall armyworm</a> (which destroys crops) both entered Australia in the past two years, leading to significant economic, social and environmental harm. </p>
<p>This comes on the top of the economic <a href="https://neobiota.pensoft.net/article/58834/">impact of invasive species</a>, such as the red imported fire ant and feral pigs, which is estimated to cost Australia up to <a href="https://theconversation.com/pest-plants-and-animals-cost-australia-around-25-billion-a-year-and-it-will-get-worse-164969">$24.5 billion annually</a>.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/pest-plants-and-animals-cost-australia-around-25-billion-a-year-and-it-will-get-worse-164969">Pest plants and animals cost Australia around $25 billion a year – and it will get worse</a>
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<p>Now, foot-and-mouth disease is knocking on our door. So how did Australia become so vulnerable to such an outbreak? Declining government support for international agricultural development must take some of the blame.</p>
<p>Between <a href="https://ses.library.usyd.edu.au/bitstream/handle/2123/14755/AVHR%20%2371%20contents%20A4Final.pdf?sequence=1&isAllowed=y">the 1970s and the early 2000s</a>, Australian aid worked with partner countries to boost animal health in Southeast Asia. This included support for the eradication of foot-and-mouth disease in The Philippines and the control of avian influenza in Indonesia.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/478660/original/file-20220811-15-vr0mgb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/478660/original/file-20220811-15-vr0mgb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/478660/original/file-20220811-15-vr0mgb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/478660/original/file-20220811-15-vr0mgb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/478660/original/file-20220811-15-vr0mgb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/478660/original/file-20220811-15-vr0mgb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/478660/original/file-20220811-15-vr0mgb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/478660/original/file-20220811-15-vr0mgb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Australia’s varroa mite outbreak has so far been contained to the east coast.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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</figure>
<p>Unfortunately, since 2013, such agricultural programs have ended or been greatly reduced in scope in line with <a href="https://donortracker.org/australia/agriculture">decreased spending in the sector</a>. The cuts came as part of broader <a href="https://acfid.asn.au/media-releases/new-oecd-data-australia%E2%80%99s-contribution-foreign-aid-remains-sluggish-despite-growing">reductions</a> to Australia’s overseas aid budget – including a cut of <a href="https://probonoaustralia.com.au/news/2020/02/australia-steps-down-aid-in-asia-as-it-steps-up-in-the-pacific/">more than 40%</a> in aid to Southeast Asia in 2020. </p>
<p>Indeed, in 2021 Australia contributed <a href="https://acfid.asn.au/media-releases/new-oecd-data-australia%E2%80%99s-contribution-foreign-aid-remains-sluggish-despite-growing">just 0.22%</a> of its gross national income towards overseas development assistance, compared to the OECD average <a href="https://www.oecd.org/dac/financing-sustainable-development/development-finance-standards/official-development-assistance.htm">of 0.33%</a> for that year. </p>
<h2>Prevention is good for the bottom line</h2>
<p>The cost of supporting effective agricultural biosecurity services in neighbouring countries would be but a small fraction of the cost of a major disease outbreak. </p>
<p>Looking forward, cost-efficient biosecurity programs <a href="https://portlandpress.com/emergtoplifesci/article/4/5/539/226789/One-Biosecurity-a-unified-concept-to-integrate">will require</a> integrated risk identification and management across human, animal, plant and environmental health. Such a joined-up approach is essential to address major and interrelated sociological and environmental biosecurity challenges. </p>
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<strong>
Read more:
<a href="https://theconversation.com/what-is-foot-and-mouth-disease-why-farmers-fear-apocalyptic-bonfires-of-burning-carcasses-186741">What is foot and mouth disease? Why farmers fear 'apocalyptic bonfires of burning carcasses'</a>
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<p>A priority in the new <a href="https://www.biosecurity.gov.au/sites/default/files/2022-08/National%20Biosecurity%20Strategy%28final%29.pdf">national biosecurity strategy</a> is to create “stronger partnerships” at the local, regional, national and international levels. One of the initial steps identified is to help shape global biosecurity standards, rules and conditions. It will also:</p>
<blockquote>
<p>“deepen international partnerships and capacity building, including in the Indo-Pacific, to increase engagement, harmonisation, skills exchanges and information sharing on national priority pests, weeds and diseases.” </p>
</blockquote>
<p>This is a great foundation for further strengthening global agricultural biosecurity systems. But to fully and effectively meet the biosecurity challenges of the 21st Century, it’s crucial to ensure agricultural biosecurity systems fully integrate with humans and our natural environment.</p>
<p>Coordinating the activities of different sectors – such as human health, agriculture and the natural environment – would result in more effective use of limited resources, especially those required to support frontline activities. This will ultimately be far better for the national budget.</p>
<h2>Broader focus on livestock health</h2>
<p>Effective agriculture aid programs require a broad focus on livestock health, rather than just tackling diseases that might threaten Australia.</p>
<p>For example, many small-scale farmers would prefer to vaccinate cows against diseases such as haemorrhagic septicaemia and anthrax that kill cattle, rather than only vaccinating them against foot-and-mouth disease which causes cows to produce less milk, but <a href="https://theconversation.com/what-is-foot-and-mouth-disease-why-farmers-fear-apocalyptic-bonfires-of-burning-carcasses-186741">won’t usually</a> kill the animal.</p>
<p>Controlling diseases with a high death rate would build trust from small-scale farmers in animal health services. This could, in turn, make rural communities more receptive to vaccinate their animals against other diseases such as foot-and-mouth disease.</p>
<p>It takes considerable effort to establish effective and efficient vaccination campaigns and other biosecurity measures. But once they’re in place, maintaining them is less costly. If funding for recurrent maintenance isn’t in place and disease outbreaks occur, this trust will be lost.</p>
<p>This lesson was learnt in Southeast Asian countries such as Indonesia and Laos during the avian influenza pandemic <a href="https://www.ncbi.nlm.nih.gov/books/NBK22151/">which started in 2003</a>. During that period, poultry producers were forced by government disease control agencies to cull affected flocks without receiving compensation. </p>
<p>The intervention still casts a shadow over relationships between producers and animal health services, <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/tbed.13673">complicating</a> efforts to control and monitor disease.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/yes-wash-your-shoes-at-the-airport-but-we-can-do-more-to-stop-foot-and-mouth-disease-ravaging-australia-187602">Yes, wash your shoes at the airport – but we can do more to stop foot-and-mouth disease ravaging Australia</a>
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<p>Beyond livestock related biosecurity risks, adequate investment is also needed in the countries of origin to improve biosecurity practices for imported plant products. </p>
<p>This includes <a href="https://www.abc.net.au/news/rural/2021-05-05/flower-industry-calls-for-more-biosecurity-funding/100115190">cut flowers</a> imported from developing countries where a 2021 investigation detected pests <a href="https://www.agriculture.gov.au/biosecurity-trade/policy/risk-analysis/plant/cut-flowers">in 12% of consignments</a>.</p>
<h2>Taking a long-term view</h2>
<p>Much work is needed to reduce the risk of further pests and diseases entering into Australia. This includes ongoing support to help our regional neighbours strengthen their biosecurity and associated food security systems.</p>
<p>Of course, this is not the only step. Australia must also ensure effective biosecurity surveillance at the border and actively engage the Australian community to report any incursions that may occur.</p>
<p>And most importantly, Australia’s biosecurity strategies must take a long-term, integrated view. These strategies must consider both benefits and costs and, crucially, have guaranteed bipartisan support at the state and federal levels.</p><img src="https://counter.theconversation.com/content/188010/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Robyn Alders is an Honorary Professor with the ANU Development Policy Centre and a Senior Consulting Fellow with the Chatham House Global Health Programme. She also consults to Australian and international aid organisations and is Chair of the Kyeema Foundation and the Upper Lachlan Branch of the NSW Farmers' Association. </span></em></p>Indonesia’s foot-and-mouth outbreak shouldn’t come as a surprise. It’s been decades in the making – just the latest consequence of biosecurity shortcomings in the region.Robyn Alders, Honorary Professor, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1865932022-07-18T13:51:24Z2022-07-18T13:51:24ZGenetically modified cowpea clears its first hurdle in Ghana, but there’s a long way to go<figure><img src="https://images.theconversation.com/files/473611/original/file-20220712-32189-ckaj53.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cowpea is a popular protein source in West Africa.</span> <span class="attribution"><span class="source">Flickr</span></span></figcaption></figure><p>Genetically modified (GM) cowpea has cleared the first of the three regulatory hurdles in the way of commercialisation in Ghana. If it is commercialised, it will be the first GM crop grown in the country – a major milestone. Biotechnology proponents have been working for decades to integrate GM crops into Ghana’s development agenda.</p>
<p>The <a href="https://bch.cbd.int/en/pdf/documents/biosafetyDecision/BCH-DEC-GH-260933/1">approval</a> of GM cowpea by the <a href="http://extwprlegs1.fao.org/docs/pdf/gha136733.pdf">National Biosafety Authority</a> comes amid debate, both <a href="https://www.fastcompany.com/90385075/in-ghana-farmers-and-scientists-debate-whether-to-use-genetically-modified-cowpea-seeds">inside</a> and <a href="https://www.devex.com/news/understanding-the-continued-opposition-to-gmos-91888#:%7E:text=Within%20the%20development%20sector%2C%20Greenpeace,abandon%20their%20campaign%20against%20GMOs.">outside</a> the country, on the efficacy of GM crops in strengthening food security throughout Africa.</p>
<p>Cowpea – black-eyed pea in some parts of the world – is a major source of protein in Ghana and the rest of the sub-continent. It is integral to Ghana’s <a href="https://www.hindawi.com/journals/aag/2018/7319204/">food security</a>. It is a staple, especially in the northern part of Ghana, where it is second only to groundnut in terms of area cultivated. Ghana is the <a href="https://www.hindawi.com/journals/aag/2018/7319204/">fifth largest producer</a> of cowpea in Africa.</p>
<p>While cowpea production is essential for Ghana, farmers face many challenges, including an array of pests. The GM cowpea has been genetically engineered to resist the <a href="https://www.aatf-africa.org/pod-borer-resistant-maruca-pbr-cowpea/">the Maruca pod borer</a>. The hope is that this resistance will help <a href="https://doi.org/10.1007/s10340-018-0974-0">decrease the amount of insecticide</a> farmers have been using to control pests and increase yields. Insecticides are <a href="https://www.frontiersin.org/articles/10.3389/fpubh.2016.00148/full">known</a> to be deleterious to human health, but their use is on the <a href="https://www.berghahnjournals.com/view/journals/environment-and-society/12/1/ares120106.xml?ArticleBodyColorStyles=full-text">rise</a> throughout Africa. </p>
<p>If Ghana commercialises GM cowpea, it will join <a href="https://theconversation.com/nigeria-has-given-a-new-gm-cowpea-variety-the-go-ahead-why-it-matters-130304">Nigeria</a> as the second country in the world to grow it. Burkina Faso may follow in commercialising it as well. While GM crops so far have a <a href="https://www.amazon.com/Africas-Gene-Revolution-Genetically-Agriculture/dp/0773559035">mixed legacy</a> in Africa, proponents hope that GM cowpea could change that narrative. </p>
<h2>Tensions over GM crops</h2>
<p>In Ghana, efforts to introduce GM crops have not gone without challenge. Since Ghanaian scientists first began conducting field trials of GM crops in 2013, a large contingent of Ghanaian civil society groups, from trade unions to farmers’ associations to advocacy organisations, have raised concerns. These include:</p>
<ul>
<li>the complex partnerships in developing GM crops and questions of ownership<br></li>
<li>the appropriateness of the technology<br></li>
<li>pricing and accompanying intellectual property rights </li>
<li>the Ghanaian government’s ability to regulate GM seeds and crops.</li>
</ul>
<p>These concerns are not necessarily unique to GM crops. However, as I write in my forthcoming book, <a href="https://msupress.org/9781611864328/we-are-not-starving">We Are Not Starving: The Struggle for Food Sovereignty in Ghana</a>, GM crops have become a vehicle to discuss not simply agricultural production, but also visions for the country’s scientific, political and agrarian future. </p>
<p>For Ghana’s small biotechnology community, GM crops represent a potentially important tool for the country’s food security strategy. </p>
<p>Critics, on the other hand, see GM crops as a narrowly conceived tool that is ill-equipped to address the structural issues that contribute to food insecurity in Ghana. </p>
<p>Further unpacking the approval of the GM cowpea helps illustrate these tensions.</p>
<h2>Hurdles remain</h2>
<p>The Ghanaian scientists overseeing the project are at the <a href="https://sari.csir.org.gh/">Savanna Agricultural Research Institute</a> (a wing of the public research institution, the Council for Scientific and Industrial Research). The next regulatory hurdles they face are the <a href="http://www.fdaghana.gov.gh/">Food and Drugs Authority</a> and the <a href="http://www.mofa.gov.gh/">National Varietal Release and Registration Committee</a>. </p>
<p>These approvals can be sought concurrently. However, given that this is Ghana’s first genetically modified crop to go through the entire approval process, even <a href="https://allianceforscience.cornell.edu/blog/2021/11/frustration-grows-over-ghanas-delay-in-approving-gm-cowpea">its biggest proponents aren’t sure</a> how long the next steps will take. </p>
<p>Once all approvals have been received, the scientists at the Savanna Agricultural Research Institute will still need to execute a plan for seed multiplication, packaging and distribution. Then GM cowpea will be ready to hit the market. In all likelihood, its availability is a year (or more) away.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/how-power-shaped-the-success-story-of-genetically-modified-cotton-in-burkina-faso-144959">How power shaped the 'success story' of genetically modified cotton in Burkina Faso</a>
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<p>A number of factors will inform whether farmers choose to purchase and grow the seed. These include availability, varietal preference, pricing, performance and exogenous considerations such as other pests. </p>
<p>An obvious but key factor is the seed’s performance. In <a href="http://csirspace.csirgh.com/bitstream/handle/123456789/1944/p15738coll2_133007.pdf?sequence=1&isAllowed=y">confined field trials</a>, GM cowpea suffered less damage from the Maruca pod-borer than non-GM cowpea. With that said, there are a multitude of other <a href="https://www.sciencedirect.com/science/article/abs/pii/S0743016721002266">diseases and pests</a> that cowpea farmers in Ghana, and elsewhere in West Africa, must contend with. Different varieties of cowpea contain <a href="https://actascientific.com/ASAG/pdf/ASAG-03-0510.pdf">varying resistance</a> to different pests, which farmers consider when deciding which variety cowpea to grow.</p>
<p>Take <a href="http://csirspace.csirgh.com/bitstream/handle/123456789/1944/p15738coll2_133007.pdf?sequence=1&isAllowed=y">Songotra</a>, the cowpea variety which has been genetically modified. Non-GM Songotra was first introduced in the Ghanaian market in 2008. In certain regions in Ghana, Songotra is <a href="https://actascientific.com/ASAG/pdf/ASAG-03-0510.pdf">susceptible</a> to other pests, especially <a href="https://doi.org/10.1016/j.cropro.2017.07.005">aphids and thrips</a>, which has led to its low adoption rate: <a href="https://www.ifpri.org/publication/adoption-gm-crops-ghana-ex-ante-estimations-insect-resistant-cowpea-and-nitrogen-use">around 10%</a>. </p>
<p>A <a href="https://www.ifpri.org/publication/adoption-gm-crops-ghana-ex-ante-estimations-insect-resistant-cowpea-and-nitrogen-use">study</a> by the International Food Policy Research Institute estimated that GM Songotra is only likely to reach a 15% adoption rate. </p>
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Read more:
<a href="https://theconversation.com/south-africa-should-rethink-regulations-on-genetically-modified-plants-176254">South Africa should rethink regulations on genetically modified plants</a>
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<p>Another hurdle the GM cowpea will face is price. The same <a href="https://www.ifpri.org/publication/adoption-gm-crops-ghana-ex-ante-estimations-insect-resistant-cowpea-and-nitrogen-use">report</a> estimated that GM cowpea could cost as much as 50% more than conventional seed. Proponents hope that the premium could be offset by the reduced use of insecticides. </p>
<p>But those savings depend on whether farmers actually do use less insecticide. That will depend, on part, on the presence of other pests. While GM cowpea has shown resistance to the Maruca pod-borer, <a href="https://doi.org/10.1007/s10340-018-0974-0">it is not resistant to other prominent pests such as thrips and aphids</a>. Farmers will still need to <a href="https://doi.org/10.1016/j.aoas.2019.03.001">deal with those pests</a>, whether with insecticides or other intervention. </p>
<h2>What’s next?</h2>
<p>The future of GM cowpea in Ghana remains to be seen, and will depend on factors like:</p>
<ul>
<li>pricing<br></li>
<li>the ability of Ghanaian scientists and their global partners to develop more popular varieties of cowpea (which they <a href="https://www.ifpri.org/publication/adoption-gm-crops-ghana-ex-ante-estimations-insect-resistant-cowpea-and-nitrogen-use">plan</a> to do)<br></li>
<li>how the GM cowpea <a href="https://www.devex.com/news/opinion-genetically-modified-crops-need-greater-farmer-inclusion-102506">performs</a> in farmers’ fields </li>
<li>the taste and consistency of cowpea once cooked </li>
<li>the availability of the seed and a market for the crop.</li>
</ul>
<p>Some civil society groups are expected to maintain <a href="https://www.modernghana.com/news/1140484/human-rights-court-hears-ghanas-first-gmo-case.html">opposition</a> to GM crops. One group, Food Sovereignty Ghana, is challenging GM cowpea in the Human Rights Court.</p>
<p>Independent monitoring and evaluation of the rollout of the seed, its performance and its farm-level impacts will be crucial. The story of GM cowpea in Ghana is far from over.</p><img src="https://counter.theconversation.com/content/186593/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Joeva Rock's research has been previously funded by the Fulbright Program, the Wenner-Gren Foundation, the Social Sciences and Humanities Research Council of Canada, the Schmidt Family Foundation, the Explorers Club, American University, New York University, and the University of Cambridge.</span></em></p>Cowpea is an important crop in Ghana. What will a genetically modified version mean for the country’s farmers?Joeva Rock, Assistant Professor in Development Studies, University of CambridgeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1794302022-06-03T12:17:46Z2022-06-03T12:17:46ZBed bugs’ biggest impact may be on mental health after an infestation of these bloodsucking parasites<figure><img src="https://images.theconversation.com/files/466798/original/file-20220602-24-e1ajb7.jpg?ixlib=rb-1.1.0&rect=597%2C134%2C1546%2C704&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Dozens of bed bugs and their eggs and fecal material on a metal bed frame.</span> <span class="attribution"><span class="source">Jerome Goddard</span></span></figcaption></figure><p>Bed bugs are back with a vengeance. After an absence of around 70 years, thanks to effective pesticides such as DDT, they’ve been popping up in fancy hotels, spas, department stores, subway trains, movie theaters – and, of course, people’s homes.</p>
<p><a href="https://scholar.google.com/citations?user=JVfeckwAAAAJ&hl=en&oi=ao">I’m a public health entomologist</a>. In the course of my work, I’ve studied these little bloodsuckers, even letting bed bugs feast on my own appendages in the name of science. <a href="https://www.cc.com/video/5klha6/the-colbert-report-threatdown-bedbugs-environmentalists-jerome-goddard">No one likes dealing with bed bugs</a> – and there are ways to minimize your chances of needing to.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="closeup of the front underside of a brown insect" src="https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=408&fit=crop&dpr=1 600w, https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=408&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=408&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=513&fit=crop&dpr=1 754w, https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=513&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=513&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Colorized scanning electron microscopic image reveals the underside of a bed bug, including the proboscis (purple) and two eyes (red).</span>
<span class="attribution"><a class="source" href="https://phil.cdc.gov/Details.aspx?pid=11739">CDC/Janice Haney Carr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Know thy bed bug enemy</h2>
<p>The common bed bug, <em>Cimex lectularius</em>, has been a parasite of humans for thousands of years. Historically, these tiny bloodsuckers were common in human dwellings worldwide, giving the old saying “sleep tight, don’t let the bed bugs bite” real meaning. They had nearly disappeared in developing countries until the mid-1990s, when they began <a href="https://doi.org/10.1093/ae/52.2.102">making a comeback</a> because of restriction or loss of certain pesticides, changes in pest control practices and increased international travel. <a href="https://medent.usyd.edu.au/bedbug/papers/doggett_icup2008.pdf">In many areas</a> around the world, they are now <a href="https://npmapestworld.org/default/assets/File/publicpolicy/executivesummaryreleasetomembersFINAL.pdf">a major urban pest</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="brown insect on white human skin, eating" src="https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A bed bug extends its beaklike proboscis to feed on human blood.</span>
<span class="attribution"><span class="source">Jerome Goddard</span></span>
</figcaption>
</figure>
<p>Adult bed bugs are less than a quarter-inch long (about 5 mm), oval-shaped and flattened, resembling unfed ticks or small cockroaches. Tucked backward underneath their head they have a long proboscis – a tubular mouthpart they can extend to take a blood meal. A bed bug needs only between three and 10 minutes to <a href="http://ipm.ucanr.edu/PMG/PESTNOTES/pn7454.html">consume up to six times its weight in blood</a> in a single meal.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Small insect sits on a dime" src="https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=537&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=537&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=537&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=675&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=675&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=675&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A yellowish-white first-stage bed bug nymph is tiny.</span>
<span class="attribution"><span class="source">Jerome Goddard</span></span>
</figcaption>
</figure>
<p>Adults are reddish brown, while the babies are extremely tiny and yellowish-white in color. They hide in cracks and crevices, generally within a few feet of a bed, coming out only to feed on an unsuspecting host. Then they run back to their hiding places, where they mate and lay eggs. </p>
<p>Houses can become infested with thousands of the little bloodthirsty pests in the mattress and box spring, where they leave telltale black fecal spots. In severe infestations there may be thick feces, hundreds of shed skins and eggs several millimeters thick.</p>
<h2>Biggest health impacts may be psychological</h2>
<p>Bed bugs have been <a href="https://doi.org/10.2307/4591852">suspected in the transmission</a> of more than 40 disease organisms, but there is <a href="https://doi.org/10.1001/jama.2009.405">little evidence bed bugs transmit human pathogens</a>, with the <a href="https://doi.org/10.4269/ajtmh.14-0483">possible exception of the microorganism that causes Chagas disease</a>. Extreme infestations can, in rare cases, lead to <a href="https://doi.org/10.1503/cmaj.090482">blood loss severe enough to cause anemia</a>.</p>
<p>Their <a href="https://www.cdc.gov/parasites/bedbugs/faqs.html">principal medical impacts</a> are related to nuisance biting and the associated itching and inflammation. The most common bite reactions are <a href="https://doi.org/10.1016/j.parint.2006.12.002">itchy red spots at feeding sites</a> that usually go away in a week or so. Some people have <a href="https://pubmed.ncbi.nlm.nih.gov/11534921/">complex skin</a> <a href="https://doi.org/10.1007/978-1-4471-1356-0">reactions</a>, <a href="https://doi.org/10.4314/wajm.v21i4.27994">including hives</a> and <a href="https://doi.org/10.1016/j.amjmed.2011.11.020">blisters</a>, or allergic responses.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="pink irritated patch on white skin of an arm" src="https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The marks from bed bug bites can persist on human skin for several days.</span>
<span class="attribution"><span class="source">Jerome Goddard and Kristine T. Edwards</span></span>
</figcaption>
</figure>
<p>Then there’s bed bugs’ <a href="http://dx.doi.org/10.1136/bmjopen-2012-000838">emotional and</a> <a href="https://doi.org/10.1016/j.amjmed.2011.08.010">psychological effects on their victims</a>. Run-ins with these parasites can trigger nervousness, anxiety and insomnia. Bed bugs commonly come with a side effect of constant worrying and feelings of shame. <a href="http://habitatservices.org/wp-content/uploads/PDF3-Bed-Bugs-Are-Back-Report.pdf">One distressed Canadian expressed it this way</a>:</p>
<blockquote>
<p>“To be honest, until you go through [an infestation], you have no idea just how horrifying it really is. It is just natural for you to become paranoid; you lose sleep, you end up dreaming and thinking about bed bugs – they just consume every fiber of your being.”</p>
</blockquote>
<p><a href="http://hdl.handle.net/1866/10783">One study of people exposed to bed bugs</a> found about half reported sleep difficulties and social isolation associated with the infestation.</p>
<p>My colleague and I analyzed <a href="https://doi.org/10.1016/j.amjmed.2011.08.010">135 internet posts concerning bed bug infestations</a>. The majority, 81% of the posts, reported three or more behaviors commonly associated with post-traumatic stress disorder – reactions like reexperiencing the event through intrusive memories and nightmares, startle responses and hypervigilance. Six posts detailed intense and repeated cleanings of homes or offices. Five posts reported persistent avoidance of people, activities and places that might lead to transmission of insects or arouse recollections of the original encounter. And five posts detailed suicidal thoughts or attempts. There are other anecdotal reports of <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3700489/">suicides</a> or drug overdoses by people struggling with bed bugs.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Bed bugs and fecal spots on a bed sheet." src="https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">You can check for the telltale marks of a bed bug infestation on a bed’s mattress and box spring.</span>
<span class="attribution"><a class="source" href="https://www.acq.osd.mil/eie/afpmb/docs/techguides/tg44.pdf">H.J. Harlan, U.S. Armed Forces Pest Management Board</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>How to protect yourself from bed bugs</h2>
<p>Not every hotel room has bed bugs, but some do. Simple precautions can help protect you and your belongings from infestation. </p>
<p>Leave all unnecessary items in your vehicle, such as extra clothing, gear and equipment. When first entering your hotel room, place luggage in the bathroom until you have had a chance to inspect the place. Pull back sheets and check the mattress and box spring for live bed bugs or black fecal spots. If any bugs or suspicious signs of infestation are found, go to the front desk and request another room. Because bed bugs don’t usually travel far on their own, other nonadjacent rooms may be perfectly clean of the parasites.</p>
<p>Keeping bed bugs out of houses and apartments can be difficult, especially if you travel a lot. After traveling, unpack luggage outside or in the garage, and wash all clothing from the luggage in hot water and dry on high heat if possible. A dryer is a great tool in the fight against bed bugs. Bed bugs can also hitch a ride into your home on used furniture or items purchased at secondhand stores or garage sales. Be sure to disinfect – more precisely “dis-insect” – those kinds of items. It’s a good idea to never purchase used mattresses or beds, no matter how good a bargain. </p>
<p>What can you do if you are forced to confront these bloodsuckers? A bed bug infestation found in a hotel room should immediately be reported to management. If you find bed bugs in your home, or in secondhand purchases, it’s best not to try to spray them yourself with over-the-counter pesticides. My recommendation is to contact a competent pest exterminator, who will treat the space with pesticides, use complex heat systems or both to kill the bugs.</p>
<p>Try not to panic. Keep in mind that bed bugs are only insects. They’re not magic. Believe me, they can be killed and eliminated from a dwelling.</p><img src="https://counter.theconversation.com/content/179430/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jerome Goddard does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Bed bugs are pretty much universally reviled. But a public health entomologist explains how – while potentially traumatizing to deal with – they aren’t likely to make you sick.Jerome Goddard, Extension Professor of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1807922022-04-22T01:55:39Z2022-04-22T01:55:39ZHow to control invasive rats and mice at home without harming native wildlife<figure><img src="https://images.theconversation.com/files/459003/original/file-20220421-19-krrb4f.jpg?ixlib=rb-1.1.0&rect=72%2C16%2C5294%2C3573&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>As I write this article, a furry blur of a rodent has just scampered across the room and under the couch. It’s autumn in Australia and, as air temperatures plunge outside, rodents start seeking the warmth and plentiful food inside our houses.</p>
<p>This is a familiar experience for many of us, whether it’s a mouse in your house, or rats invading your chicken cage or eating the fruit from your trees. </p>
<p>In fact, a <a href="https://assets.researchsquare.com/files/rs-387256/v1/4d4927bb-e1bb-4b55-8bdc-df64dead5b3c.pdf?c=1631880789">study</a> last year found rodents have cost the global economy up to US$35.53 billion between 1930 and 2018, largely due to the damage they inflict on farms.</p>
<p>Farmers along Australia’s east coast know this all too well. The rodent problem can amplify to <a href="https://theconversation.com/no-one-ever-forgets-living-through-a-mouse-plague-the-dystopia-facing-australian-rural-communities-explained-by-an-expert-159339">plague proportions</a> following wet years and warmer than average minimum temperatures. </p>
<p>Having personally experienced a mouse plague while staying on the Nullarbor, I can attest that these are horrible experiences. The economic losses are huge and the unrelenting waves of mice day and night are horrifying for those who have to live with them, sometimes for months. </p>
<p>Last year’s plague resulted in a <a href="https://theconversation.com/mouse-plague-bromadiolone-will-obliterate-mice-but-itll-poison-eagles-snakes-and-owls-too-160995">proposal to drop the poison bromadiolone</a> over large parts of eastern Australia. Had it been successful, it would have significantly harmed non-target species of native wildlife such as owls, goannas and quolls, which our research has shown are <a href="https://theconversation.com/australias-reptiles-may-be-spreading-rat-poison-through-the-food-chain-94922">highly vulnerable to a range of rodenticides</a> as they travel up the food chain.</p>
<p>Indeed, I’m often asked by people grappling with invasive rodents how best to manage them without harming native wildlife. So, here’s some advice.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1385760654519242754"}"></div></p>
<h2>Mechanical traps</h2>
<p><em>Use them indoors only</em></p>
<p>Sometimes old-fashioned is best. The snap traps you might remember from your childhood are still a highly effective way of removing pesky rodents from your home. Just keep them away from the exploring toes of children and pets! </p>
<p>Some newer plastic traps with pivoting jaws that close on the mouse are, in my experience, less effective and can risk injuring but not killing the mouse. I’ve had several experiences of traps being dragged away by a mouse caught only by a leg. </p>
<p>A new entry to the Australian market is a type of mechanical trap, the A24. It’s self-resetting with a scent-based lure and can kill 24 mice or rats on one canister. These, however, are not suitable for use outside in areas with native wildlife. </p>
<p>I recently had an horrific experience of a native quenda (bandicoot) killed by one of these traps set on my bush property. I was devastated and, after deploying a monitoring camera on the deactivated trap, I found possums are at grave risk from this type of trap, too. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/459015/original/file-20220421-14-suu48c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Bandicoot" src="https://images.theconversation.com/files/459015/original/file-20220421-14-suu48c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/459015/original/file-20220421-14-suu48c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/459015/original/file-20220421-14-suu48c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/459015/original/file-20220421-14-suu48c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/459015/original/file-20220421-14-suu48c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/459015/original/file-20220421-14-suu48c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/459015/original/file-20220421-14-suu48c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Native animals such as quenda (bandicoots) are at risk of getting caught in mechanical traps meant for invasive rodents.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>These traps don’t seem to discriminate invasive rodents from native wildlife and <a href="https://research-scotland.ac.uk/bitstream/handle/20.500.12594/53/SASA_A24_Hedgehog_Report.pdf?sequence=1">are known</a> to kill native birds, rabbits and hedgehogs in New Zealand. </p>
<p>Governments need to reconsider the ethics and conservation implications of such traps in Australia. It is my view that no mechanical traps should be set outside the home or shed where there’s risk to native wildlife. </p>
<p>The Conversation asked Goodnature, which manufactures A24 traps, whether it is taking steps to address this issue. </p>
<p>Goodnature co-founder and industrial designer Craig Bond said the traps’ threat to native animals is “ideally mitigated by the overall benefit to nature”. He said the company is working on preventative measures such as warning users, through various means, about reducing risks to native wildlife. Bond went on:</p>
<blockquote>
<p>We can and do put processes in place to mitigate and hopefully empower our trappers. And we have employed staff with the requisite expertise to do that. </p>
<p>However […] we can be more proactive in our warnings regarding the risk to non-target species. </p>
<p>The issue in the past has not been widespread but [we] understand that Australia is a particularly vulnerable environment. </p>
</blockquote>
<p>Bond said Goodnature was keen to learn more about reducing the risks its traps might pose to native Australian wildlife.</p>
<h2>Electric traps</h2>
<p><em>Effective and humane</em></p>
<p>These are battery-powered rat and mouse traps that work by delivering a fatal shock to rodents once they make contact with the two plates in the trap. </p>
<p>These are highly effective and very humane because upon touching two plates, a fatal electric shock is administered, instantly stopping the heart. </p>
<p>Though not cheap, I swear by these traps as they catch and kill quickly using a bait of your choice, such as peanut butter. There is minimal risk of impacts to non-target animals in the home. </p>
<p>But again – they definitely should not be used where native wildlife could enter the trap. The traps are usually labelled as being not for outdoor use and this advice should be followed.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/no-one-ever-forgets-living-through-a-mouse-plague-the-dystopia-facing-australian-rural-communities-explained-by-an-expert-159339">‘No one ever forgets living through a mouse plague’: the dystopia facing Australian rural communities, explained by an expert</a>
</strong>
</em>
</p>
<hr>
<h2>Live traps</h2>
<p><em>Compassionate or inhumane?</em></p>
<p>Live catch traps are popular with those not willing to kill animals. These include <a href="https://pestkill.org/mice/bucket-trap/">bucket traps</a> for dealing with large plagues. The main issue is finding ways to dispatch them. </p>
<p>Killing the invasive rodents often requires drowning them and, if the animals are not killed, you are releasing vermin for somebody else to deal with. Unless you address the problem of how they’re entering your home, they may just be back for a visit again that night. </p>
<p>Some live traps are inhumane, such as glue traps, which comprise sticky boards to capture rodents that walk over them. These traps are not recommended under any circumstances. </p>
<p>Glue traps are not only <a href="https://gala.gre.ac.uk/id/eprint/35143/7/35143_BELMAIN_An_assessment_of_animal_welfare_impacts.pdf">cruel</a> as it can take days for the animal to die, but they do not discriminate. Unless contained and used carefully, they have a high risk of catching reptiles, birds or other non-target species.</p>
<h2>Poisoned baits</h2>
<p><em>Best for industrial and broadscale use</em></p>
<p>Despite the risk to non-target animals, baits will always be needed for large scale rodent problems, such as mouse plagues. However, they are not humane as animals die slowly by blood loss over an <a href="https://onlinelibrary.wiley.com/doi/pdf/10.1002/ps.1623">average of 7.2 days</a> and have the most potential for poisoning other species.</p>
<p>In Australia, it’s almost always unnecessary to use so-called “second-generation baits” such as brodifacoum. These baits are made in response to rodents developing resistance to some chemical formulations, and require only one feed to be fatal. </p>
<p>The active ingredients in second generation baits have a very long persistence time in the liver of animals that eat them, resulting in widespread secondary poisoning along the food chain. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/mouse-plague-bromadiolone-will-obliterate-mice-but-itll-poison-eagles-snakes-and-owls-too-160995">Mouse plague: bromadiolone will obliterate mice, but it'll poison eagles, snakes and owls, too</a>
</strong>
</em>
</p>
<hr>
<p><a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0236234">Research</a> from 2020 showed invasive rodents in Australia are unlikely to have the gene for rodenticide resistance shared by their kin from Europe and North America. Consequently, some first generation products containing coumatetralyl and some natural alternatives such as zinc phosphide can be safely used in Australia to control rodents. </p>
<p>These products have a much shorter half life in the livers or rats and mice. What’s more, <a href="https://www.sciencedirect.com/science/article/abs/pii/S0048969718322836">a 2018 study</a> didn’t detect them in significant quantities in dead southern boobook owls, which eat mice. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/459009/original/file-20220421-13-k5l5w7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/459009/original/file-20220421-13-k5l5w7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/459009/original/file-20220421-13-k5l5w7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/459009/original/file-20220421-13-k5l5w7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/459009/original/file-20220421-13-k5l5w7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/459009/original/file-20220421-13-k5l5w7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/459009/original/file-20220421-13-k5l5w7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/459009/original/file-20220421-13-k5l5w7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Southern boobook owl.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>It’s also important to remember that baits must be deployed according to manufacturer’s instructions. Too often I hear stories of people throwing wax baits or grain baits into their gardens. </p>
<p>This is horrifying given the direct access this provides to possums, bandicoots, birds, small children and pets. Most baits should be deployed in bait holders that prevent exposure to non-target species.</p>
<h2>Pest management is holistic</h2>
<p>We should recognise that pest management is a holistic activity. Relying on any one technique is unlikely to be sufficient. </p>
<p>Rodent-proofing your house, shed or grain silos as much as possible is essential in the war against pests. This might include sealing water and power inlets, holes in skirting boards and gaps or holes in grain storage facilities. </p>
<p>On a commercial scale, investing in modern vermin-proof facilities such as sealed grain silos and blocking all possible gaps, may well balance out the long-term expense of baiting. They certainly come with a much reduced risk to native wildlife.</p><img src="https://counter.theconversation.com/content/180792/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Robert Davis is a member of Birdlife Australia, the Ecological Society of Australia and the Society for Conservation Biology. He has no conflicts of interest to declare.</span></em></p>With temperatures plunging, rodents have started seeking the warmth and food inside our houses. Here’s how to deal with them effectively and humanely – without accidentally catching native animals.Robert Davis, Senior Lecturer in Wildlife Ecology, Edith Cowan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1760282022-02-24T01:30:55Z2022-02-24T01:30:55ZReleasing a virus against rabbits is effective, but can make them immune if let loose at the wrong time<figure><img src="https://images.theconversation.com/files/443385/original/file-20220131-13-1oe5v55.jpg?ixlib=rb-1.1.0&rect=0%2C32%2C5356%2C3533&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Rabbits are an enormous problem for Australian ecosystems – they’re a major threat to <a href="https://www.publish.csiro.au/PC/pdf/PC18024_CO">322 species</a> of plants and animals already at risk of extinction. This is more than double the number of species threatened by cats and foxes.</p>
<p>To keep rabbit numbers down, many land managers roll out rabbit haemorrhagic disease virus, a powerful biocontrol. Land managers play a crucial role in <a href="https://www.sciencedirect.com/science/article/pii/S0006320708004199">conserving the environment</a> and <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/mec.13416">managing pest species</a> – their involvement is essential to the <a href="https://www.sciencedirect.com/science/article/pii/S0006320708004199">success</a> of many conservation programs. </p>
<p>But <a href="https://conbio.onlinelibrary.wiley.com/doi/10.1111/csp2.12639">our new research</a> finds around three quarters of land managers who reported releasing the biocontrol don’t follow the recommended guidelines, and release it during the peak rabbit breeding period. This potentially leads to the population actually <em>increasing</em> as young rabbits build an immunity to the virus. </p>
<p>It’s highly likely this widespread inappropriate use has substantial environmental and economic consequences. Rabbit haemorrhagic disease virus must be released strategically with caution, or the good intentions of land managers may have terrible outcomes.</p>
<h2>Rabbits are an enormous threat</h2>
<p>Rabbits arguably have the most significant <a href="https://www.publish.csiro.au/PC/pdf/PC18024_CO">environmental</a> and <a href="https://onlinelibrary.wiley.com/doi/pdf/10.1111/aehr.12000?casa_token=DfYxIwu-KlYAAAAA:j0hNekh_rjW5rQPmeFFN_W9LUsAgoAh_6TKcYr3-nVXWKG9GdZPqlPJxhRe3wDZUJW-6OwDVFoeKO6s">economic</a> <a href="https://www.wool.com/globalassets/wool/sheep/pest-animals/wild-dogs-foxes--pigs/iacrc_economicimpactsreport.pdf">impact</a> <a href="https://hal.archives-ouvertes.fr/hal-03333979/document">of</a> all pest animals in Australia. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/dont-underestimate-rabbits-these-powerful-pests-threaten-more-native-wildlife-than-cats-or-foxes-168288">Don't underestimate rabbits: these powerful pests threaten more native wildlife than cats or foxes</a>
</strong>
</em>
</p>
<hr>
<p>They prevent the <a href="https://www.jstor.org/stable/3543436?origin=crossref">long-term regeneration</a> of trees and shrubs by continually eating young seedlings. This has immense flow-on effects for the availability of food and <a href="https://onlinelibrary.wiley.com/doi/10.1111/j.1749-4877.2008.00078.x">shelter</a> for other animals, <a href="https://conbio.onlinelibrary.wiley.com/doi/abs/10.1111/cobi.12684">such as</a> the dusky hopping mouse, plains mouse and crest-tailed mulgara, and their ability to avoid <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ddi.13065">predators</a>. </p>
<p>Rabbits also <a href="https://www.publish.csiro.au/PC/PC090158">spread weeds</a>, support <a href="https://link.springer.com/article/10.1007/s10530-019-02131-5">populations of</a> <a href="https://www.publish.csiro.au/wr/wr00101">introduced</a> <a href="https://www.publish.csiro.au/wr/WR99065">predators</a> such as cats and foxes, cause soil erosion and <a href="https://www.sciencedirect.com/science/article/pii/S2351989420309252?via%3Dihub">reduce the ability of soil</a> to absorb moisture and support vegetation growth.</p>
<p>Reductions in rabbit numbers after 1950 have been estimated to benefit the agricultural industry to the tune of <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/aehr.12000">A$1 billion</a> annually. However, the damage they wreak still costs Australian agriculture an estimated <a href="https://ssaa.org.au/assets/news-resources/hunting/the-economic-impacts-of-vertebrate-pests-in-australia.pdf">A$200 million</a> annually.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=414&fit=crop&dpr=1 600w, https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=414&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=414&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=520&fit=crop&dpr=1 754w, https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=520&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=520&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Grazing competition from rabbits has been attributed to the decline of southern hairy-nosed wombats.</span>
<span class="attribution"><span class="source">David Taggart</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Good intentions but bad outcomes</h2>
<p>Two major viral rabbit biocontrols have been introduced to Australia: myxomatosis (introduced in 1950) and rabbit haemorrhagic disease virus (introduced in 1995). Both viruses have proven to be highly effective in reducing Australia’s rabbit numbers.</p>
<p>They now circulate naturally in Australia and continue to reduce rabbit numbers across the entire country, resulting in enormous environmental and economic benefits. Land managers can intentionally release rabbit haemorrhagic disease to help reduce rabbit numbers at more local scales, such as on a farm. But it’s crucial the biocontrol is released at the right time. </p>
<p>In young rabbits, less than <a href="https://ria.asturias.es/RIA/bitstream/123456789/7222/1/Archivo.pdf">10</a> <a href="https://www.publish.csiro.au/WR/pdf/WR00119">weeks</a> <a href="https://virologyj.biomedcentral.com/articles/10.1186/1743-422X-11-109">old</a> or so, rabbit haemorrhagic disease virus is not lethal. Instead, infection in this cohort primes their immune system and leaves them with life-long immunity to the virus. </p>
<p>It’s therefore recommended to not release rabbit haemorrhagic disease virus when young rabbits are present, as this increased immunity will make the rabbit population harder to control in future.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/443671/original/file-20220201-25-5ceges.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Two rabbits" src="https://images.theconversation.com/files/443671/original/file-20220201-25-5ceges.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/443671/original/file-20220201-25-5ceges.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/443671/original/file-20220201-25-5ceges.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/443671/original/file-20220201-25-5ceges.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/443671/original/file-20220201-25-5ceges.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/443671/original/file-20220201-25-5ceges.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/443671/original/file-20220201-25-5ceges.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Rabbits have taken a severe toll on native wildlife since they were introduced to Australia in 1859.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>So when are young rabbits present?</h2>
<p>The colloquial term “breed like rabbits” has a lot of truth to it. Rabbits can breed year-round, but their breeding predominately follows the availability of <a href="https://www.publish.csiro.au/cw/cwr9600021">green grass</a>. This is because green grass is higher in protein than dry grass, which benefits both lactating female rabbits and developing young.</p>
<p>In southern Australia, <a href="https://www.publish.csiro.au/wr/pdf/wr9870491">studies on</a> rabbit breeding patterns show they usually breed continuously between May and October. Only in the <a href="https://www.sciencedirect.com/science/article/pii/S1049964419304815?casa_token=EIDS4wrM3CUAAAAA:ybdzTCW1Wj0d-zluP5hCiQJFkMt8KZSPhuy5SSCWq5eRM_4aYs7ox4-5bEXBxfR4dpFxgQWnpA">severest of droughts</a> do they not breed during this period. </p>
<p>When we account for the duration of rabbit pregnancy (28-31 days) and that young rabbits up to 10 weeks old aren’t killed by the biocontrol, we can generally expect young rabbits to be continuously present between July and December. </p>
<p>As a result, rabbit haemorrhagic disease virus should not be released between July and December.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/explainer-how-biocontrol-fights-invasive-species-31298">Explainer: how 'biocontrol' fights invasive species</a>
</strong>
</em>
</p>
<hr>
<p>And yet, <a href="https://conbio.onlinelibrary.wiley.com/doi/10.1111/csp2.12639">our new research</a> shows 47% of all biocontrol supply and 74% of reported releases occurs during this major anticipated rabbit breeding season, when the risk of immunising young rabbits is greatest. In fact, we found unseasonal biocontrol use in all states except Tasmania and the ACT where the data were insufficient.</p>
<p>This is a major problem, as the young rabbits’ <a href="https://www.publish.csiro.au/WR/pdf/WR00119">life-long</a> <a href="https://virologyj.biomedcentral.com/articles/10.1186/1743-422X-11-109">immunity</a> will lead to their increased survival and recruitment into the breeding population. This was confirmed experimentally in <a href="https://onlinelibrary.wiley.com/doi/pdf/10.1111/tbed.14421?casa_token=9cIM4wPEeZ4AAAAA:AZYGrkHmo-qgZE-Ucr1NrQ53ja5DcUlzAAg6qbwdcvVXCK4fM36Xu4glGjmgMW50EFwSBqnhjhdPUvk">a study</a> last year on European rabbits, which showed releasing a very similar virus during the breeding season does indeed lead to the increased survival of young rabbits.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/443388/original/file-20220131-17-gncjxj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/443388/original/file-20220131-17-gncjxj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/443388/original/file-20220131-17-gncjxj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=385&fit=crop&dpr=1 600w, https://images.theconversation.com/files/443388/original/file-20220131-17-gncjxj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=385&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/443388/original/file-20220131-17-gncjxj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=385&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/443388/original/file-20220131-17-gncjxj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=484&fit=crop&dpr=1 754w, https://images.theconversation.com/files/443388/original/file-20220131-17-gncjxj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=484&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/443388/original/file-20220131-17-gncjxj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=484&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Rabbits don’t breed in only the severest of droughts in Australia.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Where do we go from here?</h2>
<p>The management of rabbits, or any pest species, must be strategic and given appropriate critical thought. If this isn’t done, negative consequences can and do occur. The last thing we want is to make our problem worse.</p>
<p>In the case of rabbit haemorrhagic disease virus and rabbit management, we must consider restricting access to the virus, either with seasonal restrictions or restricting its use to people who are highly specialised and trained. </p>
<p>We must also practice integrated pest management. This is where no single management technique is considered a silver bullet, and land managers employ a range of measures to achieve the optimal outcome. When managing rabbits at local scales, we should more strongly consider other management techniques, such as the removal of warrens, burrows or above-ground harbor, trapping, fencing, warren fumigation, shooting or poison baiting. </p>
<p>Many pest animals and plants are managed worldwide for both environmental and economic reasons, and land managers are often encouraged to contribute, and asked to follow implementation guidelines. Our study is a warning to other conservation activities – land managers must follow these important guidelines or they may see problems get worse. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/one-cat-one-year-110-native-animals-lock-up-your-pet-its-a-killing-machine-138412">One cat, one year, 110 native animals: lock up your pet, it's a killing machine</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/176028/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Pat Taggart works for the Department of Primary Industries NSW and receives funding from the Centre for Invasive Species Solutions, and the Federal Department of Agriculture, Water and the Environment. </span></em></p>New research finds 74% of land managers who reported releasing a powerful biocontrol release it during the peak rabbit breeding period. This can lead to rabbit populations actually increasing.Pat Taggart, Adjunct Fellow, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1705532022-01-03T19:13:13Z2022-01-03T19:13:13ZMoths eating your clothes? It’s actually their hungry little caterpillars – here’s how to get rid of them<figure><img src="https://images.theconversation.com/files/428169/original/file-20211025-23-10uv8qs.jpg?ixlib=rb-1.1.0&rect=0%2C7%2C5168%2C3430&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Have you opened your post-lockdown wardrobe, only to discover some of your beautiful summer clothes have holes in them? You’re probably blaming clothes moths but the real culprits are the larvae (caterpillars). </p>
<p>But who are these moths? The fact that they’re feeding on your precious clothes, fabrics and yarn actually reflects an interesting and – for moths – unusual biology. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-how-do-moths-eat-our-clothes-105978">Curious Kids: How do moths eat our clothes?</a>
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</em>
</p>
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<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/431625/original/file-20211112-21-jhwzu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/431625/original/file-20211112-21-jhwzu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/431625/original/file-20211112-21-jhwzu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/431625/original/file-20211112-21-jhwzu1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/431625/original/file-20211112-21-jhwzu1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/431625/original/file-20211112-21-jhwzu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/431625/original/file-20211112-21-jhwzu1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/431625/original/file-20211112-21-jhwzu1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">What can you do to protect your precious clothes, fabrics and yarn from the hungry larvae?</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>An old foe</h2>
<p><a href="https://liverpool.universitypressscholarship.com/view/10.5949/liverpool/9780859892841.001.0001/upso-9780859892841">Early references</a> to clothes moths in Greek and Roman literature suggest humans have been battling clothes moths for thousands of years. Clothes moths are part of an ancient lineage of moths (<a href="https://www.pnas.org/content/116/45/22657">Tineidae</a>) and as such have preserved some quirky behaviours and adaptions that have led to a few species becoming pests.</p>
<p>The most well-known species of clothes moths in Australia are the webbing clothes moth (<em>Tineola bisselliella</em>) and the case-making clothes moth (<em>Tinea pellionella</em>). These common names refer to the appearance of silk spun by the caterpillars as shelter.</p>
<p>The adult clothes moth ranges in size from 4mm to 9mm – about the size of a grain of rice. Once the larvae turn into adult moths, they never eat again. </p>
<h2>An inconvenient diet</h2>
<p>The evolutionary origin of clothes moths diverged from 98% of all other moths a <a href="https://www.pnas.org/content/116/45/22657">long time ago</a>, so these moths do some things differently from most other moths.</p>
<p>Most tineid species don’t feed on living plants like “normal” caterpillars, but on rotting wood, fungi, lichens, detritus and even <a href="https://link.springer.com/article/10.1007/s11676-014-0503-9">bat poo in caves</a>. So it is unsurprising some species even <a href="https://www.sciencedirect.com/science/article/pii/S0022474X05000731">feed on the keratin</a> (a kind of protein) found in natural fibres. </p>
<p>They love to nibble on items derived from animals such as fur, wool and silk. But the synthetics or mixed fibres in your wardrobe aren’t safe either. Clothes moth larvae have been known to feed on <a href="https://agris.fao.org/agris-search/search.do?recordID=US19830893890">synthetic and blended fibres</a>, particularly those stained with sweat or food. The preferred diet of these caterpillars means some species have become unwelcome pests in our homes. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/428168/original/file-20211025-25-1wl7jd9.jpg?ixlib=rb-1.1.0&rect=0%2C42%2C4031%2C2975&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/428168/original/file-20211025-25-1wl7jd9.jpg?ixlib=rb-1.1.0&rect=0%2C42%2C4031%2C2975&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/428168/original/file-20211025-25-1wl7jd9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/428168/original/file-20211025-25-1wl7jd9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/428168/original/file-20211025-25-1wl7jd9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/428168/original/file-20211025-25-1wl7jd9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/428168/original/file-20211025-25-1wl7jd9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/428168/original/file-20211025-25-1wl7jd9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">They love to nibble on items derived from animals such as fur, wool and silk. But synthetics or mixed fibres aren’t safe either.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Not all clothes moths are pests!</h2>
<p>Fortunately, only a few species from this group containing over 2,600 species are pests. In Australia we have over 190 known species of moths belonging to the clothes moth group, and many more unnamed specimens located at the <a href="https://www.csiro.au/en/about/facilities-collections/collections/anic">Australian National Insect Collection</a> are waiting for scientists to formally name them. </p>
<p>Researchers are working to understand more about the diversity and behaviour of moths that feed in unconventional ways, including the authors of this article. One of us (Ying Luo) is currently studying moths whose <a href="https://antomology.wordpress.com/2021/09/22/what-is-a-leaf-miner/">larvae feed inside a leaf</a>, rather than on the outside of a leaf. Luckily, you won’t find these inside your wardrobe. </p>
<h2>Why are they in my house – and how do I get rid of them?</h2>
<p>The introduced clothes moths are a well-established pest in Australia and were brought here by accident. But how did they get into <em>your</em> house? </p>
<p>Sadly, you probably brought the eggs or larvae home yourself. They may have been hidden in a piece of clothing thrifted from the op-shop, borrowed from a friend or even bought new from a big brand store.</p>
<p>One of the best methods for keeping on top of clothes moths is to regularly check your clothing. Like their wild cousins, clothes moths enjoy dark, enclosed spaces. </p>
<p>You could try packing your clothes away in plastic tubs or bags, but this may mean you check on your clothes less often. You could risk sealing in some clothes moth larvae with your clothes. </p>
<p>If you haven’t been using certain clothes – the summer clothes packed away during winter for example, or any work or going-out clothes that stayed in the wardrobe during lockdown – then this is the perfect environment for clothes moths larvae to settle in for a nice, undisturbed feast.</p>
<p>Bring them out for washing and airing every now and then, and you could even give your wardrobe a refresh while you’re at it. </p>
<p>If you already have an infestation, you should remove all your clothing from the wardrobe and give the space a good vacuum. Some larvae may even be present in the carpet (if you have it). Wash all clothing before putting it back into the wardrobe. </p>
<h2>What about moth balls?</h2>
<p>Modern mothballs are a crystallised form of a chemical known as <a href="https://en.wikipedia.org/wiki/1,4-dichlorobenzene">1,4-dichlorobenzene</a> (C₆H ₄Cl₂). </p>
<p>Over time, it turns (or “sublimates”) into a gas, which produces the strong smell you probably associate with moth balls.</p>
<p>They are used to deter moths – but if you already have an infestation, mothballs will not help. </p>
<p>And you may need quite a high concentration to be effective. At that point, you might not particularly enjoy the strong smell of the mothballs on your clothes. </p>
<p>Here at the <a href="https://www.csiro.au/en/about/facilities-collections/collections/anic">Australian National Insect Collection</a> even we have to keep an eye out for unwanted insects! </p>
<p>We use a commercial form of “moth balls” to deter pests, and quarantine incoming specimens to prevent future infestations. But don’t worry about quarantining your clothes, we’ve found that careful observation is also an effective way to stay on top of pesty moths!</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/431626/original/file-20211112-1788-18bgx6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/431626/original/file-20211112-1788-18bgx6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/431626/original/file-20211112-1788-18bgx6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/431626/original/file-20211112-1788-18bgx6j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/431626/original/file-20211112-1788-18bgx6j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/431626/original/file-20211112-1788-18bgx6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/431626/original/file-20211112-1788-18bgx6j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/431626/original/file-20211112-1788-18bgx6j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">If you already have an infestation, mothballs will not help.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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</figure><img src="https://counter.theconversation.com/content/170553/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ying Luo's PhD is funded by an ABRS grant. She is also affiliated with the Research School of Biology at ANU, as her PhD is done through ANU.</span></em></p><p class="fine-print"><em><span>Andreas Zwick is a research scientist in the Australian National Insect Collection, CSIRO. He is affiliated with the Australian Entomological Society, the Societas Europaea Lepidopterologica and the Japan Heterocerists' Society.</span></em></p>Once the larvae turn into adult moths, they never eat again.Ying Luo, PhD Candidate at the Research School of Biology, Australian National UniversityAndreas Zwick, Molecular Systematist, CSIROLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1720582021-11-19T21:16:50Z2021-11-19T21:16:50ZInvasive species are threatening Antarctica’s fragile ecosystems as human activity grows and the world warms<figure><img src="https://images.theconversation.com/files/432765/original/file-20211118-16-1mxc0bd.JPG?ixlib=rb-1.1.0&rect=16%2C16%2C3626%2C2714&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Dana Bergstrom</span>, <span class="license">Author provided</span></span></figcaption></figure><p>We tend to think Antarctica is isolated and far away – biologically speaking, this is true. But the continent is busier than you probably imagine, with many national programs and tourist operators crisscrossing the globe to get there. </p>
<p>And each vessel, each cargo item, and each person could be harbouring non-native species, hitchhiking their way south. This threat to Antarctica’s fragile ecosystem is what <a href="https://www.cell.com/trends/ecology-evolution/fulltext/S0169-5347(21)00277-9">our new evaluation</a>, released today, grapples with. </p>
<p>We mapped the last five years of planes and ships visiting the continent, illuminating for the first time the extent of travel across the hemispheres and the potential source locations for non-native species, as the map below shows. We found that, luckily, while some have breached Antarctica, they generally have yet to get a stranglehold, leaving the continent still relatively pristine. </p>
<p>But Antarctica is getting busier, with new research stations, <a href="https://future.usap.gov/updated-plans-mcmurdo-modernization/">rebuilding</a> and <a href="https://www.nzherald.co.nz/travel/antarctica-by-private-jet-luxury-wolfs-fang-camp-launches-with-cape-town-link/DF7HCWGT5R3EWWBK32UJWMYLBM/">more tourism</a> activities planned. Our challenge is to keep it pristine under this growing human activity and climate change threat.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/432778/original/file-20211119-28-1ququaq.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/432778/original/file-20211119-28-1ququaq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/432778/original/file-20211119-28-1ququaq.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=679&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432778/original/file-20211119-28-1ququaq.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=679&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432778/original/file-20211119-28-1ququaq.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=679&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432778/original/file-20211119-28-1ququaq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=853&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432778/original/file-20211119-28-1ququaq.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=853&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432778/original/file-20211119-28-1ququaq.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=853&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="license">Author provided</span></span>
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</figure>
<h2>Life evolved in isolation</h2>
<p>Biodiversity-wise, much of the planet is mixed up. The scientific term is <em>homogenisation</em>, where species, such as weeds, pests and diseases, from one place are transported elsewhere and establish. This means they begin to reproduce and influence the ecosystem, often to the detriment of the locals.</p>
<p>Most life in Antarctica is jammed onto tiny coastal ice-free fringes, and this is <a href="https://theconversation.com/for-the-first-time-we-can-measure-the-human-footprint-on-antarctica-112856">where most research stations</a>, ships and people are. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/do-assessments-of-fish-stock-sustainability-work-for-consumers-11285">Do assessments of fish stock sustainability work for consumers?</a>
</strong>
</em>
</p>
<hr>
<p>This includes unique animals (think Adélie penguins, Weddell seals and snow petrels), mosses and lichens that harbour tiny invertebrates (such as mites, waterbears and springtails), and an array of microbes such as cyanobacteria. The <a href="https://www.youtube.com/watch?v=RAnacKx7Rp4&list=PLdZhBu9Pg1H-mlI5ic4tlcF46lD-vM0hA&index=17">adjacent coast</a> and ocean team with life, too. </p>
<p>The more we learn about them, the more outstanding life at the end of the planetary spectrum becomes. Just this week, new scientific discoveries identified <a href="https://theconversation.com/antarctic-bacteria-live-on-air-and-make-their-own-water-using-hydrogen-as-fuel-171808">that some Antarctic bacteria live on air</a>, and make their own water using hydrogen as fuel. </p>
<p>When the Southern Ocean was formed some 30 million years ago, natural barriers were created with the rest of the world. This includes the <a href="https://theconversation.com/explainer-how-the-antarctic-circumpolar-current-helps-keep-antarctica-frozen-106164">Antarctic Circumpolar Current</a>, the strongest ocean current on the planet, and its associated strong westerly surface winds, icy air and ocean temperatures.</p>
<p>This means life in Antarctica evolved in isolation, with flora and fauna that commonly exist nowhere else and can cope with frigid conditions. But the simplicity of Antarctica’s food webs can often mean there are gaps in the ecosystem that other species from around the world can fill.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/explainer-how-the-antarctic-circumpolar-current-helps-keep-antarctica-frozen-106164">Explainer: how the Antarctic Circumpolar Current helps keep Antarctica frozen</a>
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</em>
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<hr>
<p>In May 2014, for example, routine biosecurity surveillance <a href="https://link.springer.com/article/10.1007/s10530-017-1551-9">detected non-native springtails</a> (tiny insect-like invertebrates) in a hydroponic facility at an Australian Antarctic station. </p>
<p>This station, an ice-free oasis, previously lacked these interlopers, and they had the potential to alter the local fragile ecosystem permanently. Thankfully, a rapid and effective response successfully eradicated them.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/432791/original/file-20211119-26-k7xbb6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Penguin sitting on moss" src="https://images.theconversation.com/files/432791/original/file-20211119-26-k7xbb6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/432791/original/file-20211119-26-k7xbb6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432791/original/file-20211119-26-k7xbb6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432791/original/file-20211119-26-k7xbb6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432791/original/file-20211119-26-k7xbb6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432791/original/file-20211119-26-k7xbb6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432791/original/file-20211119-26-k7xbb6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Gentoo penguin on a bed of algae, Antarctica</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Pressures from climate change are exacerbating the challenges of human activity on Antarctica, as climate change is bringing milder conditions to these wildlife-rich areas, both on land and sea.</p>
<p>As glaciers melt, new areas are exposed, which allows non-Antarctic species <a href="https://theconversation.com/the-winners-and-losers-of-antarcticas-great-thaw-80140">greater opportunity to establish</a> and possibly outcompete locals for resources, such as nutrients and precious, ice-free space.</p>
<h2>So far, we’ve been lucky</h2>
<p>Our past research focused on non-native propagules – things that propagate like microbes, viruses, seeds, spores, insects and pregnant rats – and how they entrain themselves into Antarctica. </p>
<p>They can be easily caught on people’s clothing and equipment, in fresh food, cargo and machinery. In fact, research from the last decade found that visitors who hadn’t cleaned their clothing and equipment carried on average <a href="https://www.pnas.org/content/109/13/4938.short">nine seeds each</a>. </p>
<figure class="align-center ">
<img alt="How non-native species get to Antarctica" src="https://images.theconversation.com/files/432585/original/file-20211118-13-854n2x.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/432585/original/file-20211118-13-854n2x.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432585/original/file-20211118-13-854n2x.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432585/original/file-20211118-13-854n2x.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432585/original/file-20211118-13-854n2x.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432585/original/file-20211118-13-854n2x.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432585/original/file-20211118-13-854n2x.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Pathways for non native species.</span>
<span class="attribution"><span class="source">Dana M Bergstrom</span></span>
</figcaption>
</figure>
<p>But few non-native species have established in Antarctica, despite their best efforts.</p>
<p>To date, only 11 non-native invertebrate species – including springtails, mites, a midge and an earthworm – have established across a range of locations in the warmer parts of Antarctica, including Signy Island and the Antarctic Peninsula. In the marine realm, some non-native species have been seen but it’s thought none have survived and established. </p>
<p>Microbes are another matter. <a href="https://theconversation.com/covid-has-reached-antarctica-scientists-are-extremely-concerned-for-its-wildlife-154481">Each visitor</a> to Antarctica carries millions of microbial passengers, and many of these microbes are left behind. Around most research stations, human gut microbes from sewage have mingled with native microbes, including exchanging antibiotic resistance genes. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/covid-has-reached-antarctica-scientists-are-extremely-concerned-for-its-wildlife-154481">COVID has reached Antarctica. Scientists are extremely concerned for its wildlife</a>
</strong>
</em>
</p>
<hr>
<p>Last year, for example, a rare harmful bacteria, pathogenic to both humans and birds, was detected in guano (poo) from both Adélie and gentoo penguin colonies at sites with high rates of human visitors. COVID-19 also made its way to Antarctica last December. </p>
<p>Both these cases risk so-called “reverse zoonosis”, where humans spread disease to local wildlife.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/432573/original/file-20211118-20-u6nlqa.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/432573/original/file-20211118-20-u6nlqa.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/432573/original/file-20211118-20-u6nlqa.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432573/original/file-20211118-20-u6nlqa.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432573/original/file-20211118-20-u6nlqa.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432573/original/file-20211118-20-u6nlqa.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432573/original/file-20211118-20-u6nlqa.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432573/original/file-20211118-20-u6nlqa.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Antarctica’s coral reefs? Extensive shallow water, polychete colonies form fragile reefs that act as marine animal forests, hosting a diverse and abundant community of associated plants and animals.</span>
<span class="attribution"><span class="source">Jonny Stark/ AAD</span></span>
</figcaption>
</figure>
<h2>What do we do about it?</h2>
<p>Three factors have helped maintain Antarctica’s near-pristine status: the physical isolation, cold conditions and co-operation between nations through the Antarctic Treaty. The Treaty is underpinned by the Environmental Protocol, which aims to prevent and respond to threats and pressures to the continent. </p>
<p>There is unanimous commitment from Antarctic Treaty nations towards preventing the establishment of non-native species. This includes adopting a science-based, <a href="https://documents.ats.aq/ATCM39/ww/atcm39_ww009_e.pdf">non-native species manual</a>, which provides guidance on how to prevent, monitor, and respond to introductions of non-native species.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/existential-threat-to-our-survival-see-the-19-australian-ecosystems-already-collapsing-154077">'Existential threat to our survival': see the 19 Australian ecosystems already collapsing</a>
</strong>
</em>
</p>
<hr>
<p>But time is of the essence. We must better prepare for the inevitable arrival of more non-native species to prevent them from establishing, as we continue to break the barriers protecting Antarctica. One approach is to tailor the newly developed <a href="https://theconversation.com/existential-threat-to-our-survival-see-the-19-australian-ecosystems-already-collapsing-154077">3As approach to environmental management</a>: Awareness of values, Anticipation of the pressures, Action to stem the pressures.</p>
<p>This means ramping up monitoring, taking note of predictions of what <a href="https://doi.org/10.1111/gcb.14938">non-native species could sneak through biosecurity</a> and establish under new conditions, and putting in place pre-determined response plans to act quickly when they do.</p><img src="https://counter.theconversation.com/content/172058/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dana Bergstrom works for the Australian Antarctic Division and is a Visiting Fellow at the University of Wollongong. Her research and fieldwork in Antarctica was supported by the Australian Antarctic Division.</span></em></p><p class="fine-print"><em><span>Shavawn Donoghue receives funding from Australian Antarctic Program.</span></em></p>While some invasive animals have breached Antarctica, the continent is still pristine. Our challenge is keeping it that way.Dana M Bergstrom, Principal Research Scientist, University of WollongongShavawn Donoghue, Adjunct Researcher, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1682882021-10-21T01:00:57Z2021-10-21T01:00:57ZDon’t underestimate rabbits: these powerful pests threaten more native wildlife than cats or foxes<figure><img src="https://images.theconversation.com/files/427443/original/file-20211020-20-1igkl3u.jpg?ixlib=rb-1.1.0&rect=34%2C40%2C3847%2C2543&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>In inland Australia, rabbits have taken a severe toll on native wildlife since they were <a href="https://www.nma.gov.au/defining-moments/resources/rabbits-introduced">introduced in 1859</a>. They may be small, but today rabbits are a key threat to <a href="https://www.publish.csiro.au/pc/pc18024">322 species</a> of Australia’s at-risk plants and animals — more than twice the number of species threatened by cats or foxes. </p>
<p>For example, research shows even just one rabbit in two hectares of land can solely destroy <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1442-9993.1988.tb01414.x">every regenerating sheoak seedling</a>. Rabbits are also responsible for the historic declines of the iconic <a href="https://www.publish.csiro.au/am/AM15046">southern hairy-nosed wombat</a> and red kangaroo.</p>
<p><a href="https://onlinelibrary.wiley.com/doi/full/10.1111/rec.13552">Our latest research</a> looked at the conservation benefits following the introduction of three separate <a href="https://theconversation.com/explainer-how-biocontrol-fights-invasive-species-31298">biocontrols</a> used to manage rabbits in Australia over the 20th Century — all three were stunningly successful and resulted in enormous benefits to conservation. </p>
<p>But today, rabbits are commonly <a href="https://www.publish.csiro.au/rj/rj16047">ignored or underestimated</a>, and aren’t given appropriate attention in conservation compared to introduced predators like cats and foxes. This needs to change.</p>
<h2>Why rabbits are such a serious problem</h2>
<p>Simply put, rabbits are a major problem for Australian ecosystems because they destroy huge numbers of critical regenerating seedlings over more than half the continent. </p>
<p>Rabbits can <a href="https://agris.fao.org/agris-search/search.do?recordID=AV20120153810">prevent</a> the long-term <a href="https://link.springer.com/chapter/10.1007/978-3-540-72446-9_9">regeneration</a> of trees and shrubs by continually eating young seedlings. This keeps ecosystems from ever reaching their natural, pre-rabbit forms. This has immense flow-on effects for the availability of food for plant-eating animals, for insect abundance, <a href="https://onlinelibrary.wiley.com/doi/10.1111/j.1749-4877.2008.00078.x">shelter</a> and <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ddi.13065">predation</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=414&fit=crop&dpr=1 600w, https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=414&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=414&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=520&fit=crop&dpr=1 754w, https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=520&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/427455/original/file-20211020-26249-1im7uvu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=520&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Grazing competition from rabbits has been attributed to the decline of southern hairy-nosed wombats.</span>
<span class="attribution"><span class="source">David Taggart</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>In some ecosystems, rabbits have prevented the regeneration of plant communities for <a href="https://www.jstor.org/stable/3543436?origin=crossref">130 years</a>, resulting in shrub populations of only old, scattered individuals. These prolonged impacts may undermine <a href="https://onlinelibrary.wiley.com/doi/10.1111/aec.12880">the long-term success</a> of conservation programs to reintroduce mammals to the wild.</p>
<p>Things are particularly dire in arid Australia where, in drought years, rabbits can eat a high proportion of the vegetation that grows, leaving little food for native animals. Arid vegetation is slow growing and doesn’t regenerate often as rainfall is infrequent. This means rabbits can have a severe toll on wildlife by swiftly eating young trees and shrubs soon after they emerge from the ground. </p>
<p>Rabbits eat a high proportion of regenerating vegetation even when their population is at <a href="https://www.publish.csiro.au/bt/bt15208">nearly undetectable levels</a>. For example, it took the complete eradication of rabbits from the semi-arid TGB Osborn reserve in South Australia, before <a href="https://www.publish.csiro.au/BT/BT04144">most tree and shrub</a> species could regenerate. </p>
<p>Rabbits also <a href="https://www.publish.csiro.au/PC/PC090158">spread weeds</a>, cause soil erosion and <a href="https://www.sciencedirect.com/science/article/pii/S2351989420309252?via%3Dihub">reduce the ability of soil</a> to absorb moisture and support vegetation growth.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/427414/original/file-20211020-15-1cg2367.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/427414/original/file-20211020-15-1cg2367.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/427414/original/file-20211020-15-1cg2367.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=385&fit=crop&dpr=1 600w, https://images.theconversation.com/files/427414/original/file-20211020-15-1cg2367.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=385&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/427414/original/file-20211020-15-1cg2367.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=385&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/427414/original/file-20211020-15-1cg2367.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=484&fit=crop&dpr=1 754w, https://images.theconversation.com/files/427414/original/file-20211020-15-1cg2367.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=484&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/427414/original/file-20211020-15-1cg2367.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=484&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Rabbits spread weeds and eat seedlings.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>If you control prey, you control predators</h2>
<p>When restoring ecosystems, particularly in arid Australia, it’s common for land managers to heavily focus on managing predators such as cats and foxes, while ignoring rabbits. While predator management is important, neglecting rabbit control may mean Australia’s unique fauna is still destined to decline.</p>
<p><a href="https://link.springer.com/article/10.1007/BF00378734">Cats</a> and <a href="https://link.springer.com/article/10.1007/BF00319021">foxes</a> eat a lot of rabbits in arid Australia and can limit their populations when rabbit numbers are low. A common argument <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/jbi.12469">against rabbit control</a> is that cats and foxes will turn to eating native species in the absence of rabbits. But this argument is unfounded. </p>
<p>Cats and foxes may turn from rabbits to native species in the immediate short-term. But, research has also shown fewer rabbits ultimately lead to declines in <a href="https://link.springer.com/article/10.1007/s10530-019-02131-5">cat</a> <a href="https://www.publish.csiro.au/wr/wr00101">and</a> <a href="https://www.publish.csiro.au/wr/WR99065">fox</a> numbers, as the cats and foxes are starved of their major food source. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/427441/original/file-20211020-21-3tskzo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/427441/original/file-20211020-21-3tskzo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/427441/original/file-20211020-21-3tskzo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/427441/original/file-20211020-21-3tskzo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/427441/original/file-20211020-21-3tskzo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/427441/original/file-20211020-21-3tskzo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/427441/original/file-20211020-21-3tskzo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/427441/original/file-20211020-21-3tskzo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Culling rabbits starves feral predators of their major food source.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Regrowth could be seen from space</h2>
<p>An effective way to deal with rabbits is to release biocontrol agents - natural enemies of rabbits, such as viruses or parasites. Our research reviewed the effects of rolling out three different biocontrols last century:</p>
<ul>
<li><p>myxomatosis (an infectious rabbit disease), released in 1950 </p></li>
<li><p>European rabbit fleas (as a vector of myxomatosis), released in 1968 </p></li>
<li><p>rabbit haemorrhagic disease, released in 1995. </p></li>
</ul>
<p>Each lead to unprecedented reductions in the number of rabbits across Australia. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/427643/original/file-20211020-16-2wsx08.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/427643/original/file-20211020-16-2wsx08.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/427643/original/file-20211020-16-2wsx08.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/427643/original/file-20211020-16-2wsx08.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/427643/original/file-20211020-16-2wsx08.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/427643/original/file-20211020-16-2wsx08.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/427643/original/file-20211020-16-2wsx08.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/427643/original/file-20211020-16-2wsx08.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Rabbits eventually built up a tolerance to biocontrols.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Despite the minor interest in conservation at the time, the spread of myxomatosis led to <a href="https://onlinelibrary.wiley.com/doi/10.1111/j.1442-9993.1988.tb01414.x">widespread regeneration in sheoaks</a> for over five years, before rabbit numbers built back up. <a href="https://www.sciencedirect.com/science/article/abs/pii/S2352249617300319">Red kangaroo populations</a> increased so much that landholders were suddenly “<a href="https://trove.nla.gov.au/newspaper/article/48116423?searchTerm=Pests%20follow%20the%20rain%20in%20N-E%20drought#">involved in a shooting war with hordes of kangaroos invading their properties</a>”, according to a newspaper report at the time. </p>
<p>Following the introduction of the European rabbit flea, <a href="https://catalogue.nla.gov.au/Record/1338918">native grasses</a> became prolific along the Mount Lofty Ranges, South Australia. Similarly, southern hairy-nosed wombats and <a href="https://www.publish.csiro.au/am/am19037">swamp wallabies</a> expanded their ranges.</p>
<p>By the time rabbit haemorrhagic disease was introduced in 1995, interest in conservation and the environment had grown and conservation benefits were better recorded.</p>
<p><a href="https://www.publish.csiro.au/book/6508/">Native vegetation</a> <a href="https://www.publish.csiro.au/bt/bt15208">regenerated</a> over enormous spans of land, including native pine, needle bush, umbrella wattle, witchetty bush and twin-leaved emu bush. This regeneration was so significant across large parts of the Simpson and Strzelecki Deserts, it could be <a href="https://www.sciencedirect.com/science/article/abs/pii/S0034425717302171">seen from space</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/427404/original/file-20211020-20-1bfrfzu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/427404/original/file-20211020-20-1bfrfzu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/427404/original/file-20211020-20-1bfrfzu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/427404/original/file-20211020-20-1bfrfzu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/427404/original/file-20211020-20-1bfrfzu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/427404/original/file-20211020-20-1bfrfzu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/427404/original/file-20211020-20-1bfrfzu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/427404/original/file-20211020-20-1bfrfzu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">When rabbits were controlled, the number of red kangaroos doubled.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p><a href="https://link.springer.com/chapter/10.1007/978-3-540-72446-9_19">Red kangaroos</a> became two to three times more abundant, and <a href="https://conbio.onlinelibrary.wiley.com/doi/10.1111/cobi.12684">multiple species of desert rodent and a small marsupial carnivore</a> (dusky hopping mouse, spinifex hopping mouse, plains rat, crest-tailed mulgara) all expanded their ranges.</p>
<p>But each time, after 10 to 20 years, the biocontrols stop working so well, as rabbits eventually built up a tolerance to the diseases. </p>
<h2>So what should we do today?</h2>
<p>Today, there are an estimated <a href="https://www.nma.gov.au/defining-moments/resources/rabbits-introduced">150-200 million rabbits</a> in Australia, we need to be on the front foot to manage this crisis. This means researchers should continually develop new biocontrols — which are clearly astonishingly successful.</p>
<p>But this isn’t the only solution. The use of biocontrols must be integrated with conventional rabbit management techniques, <a href="https://www.publish.csiro.au/WR/WR09103">including destroying</a> warrens (burrow networks) and harbours (above-ground rabbit shelters), baiting, fumigation, shooting or trapping.</p>
<p>Land managers have a major part to play in restoring Australia’s arid ecosystems, too. Land managers are required by law to control invasive pests such as rabbits, and this must occur humanely using approved and recognised methods. </p>
<p>They, and researchers, must take rabbit management seriously and give it equal, if not more, attention than feral cats and foxes. It all starts with a greater awareness of the problem, so we stop underestimating these small, but powerful, pests. </p>
<p><em>The authors would like to acknowledge the significant contribution of Dr Graeme Finlayson from Bush Heritage Australia, who is the lead author of the published study.</em></p><img src="https://counter.theconversation.com/content/168288/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Pat Taggart works for the Department of Primary Industries NSW. He receives funding from the Federal Department of Agriculture, Water and Environment, and the Centre for Invasive Species Solutions. </span></em></p><p class="fine-print"><em><span>Brian Cooke is an adjunct Associate Professor at the University of Canberra. He previously worked for the South Australian Government and CSIRO on biological control of rabbits. He is affiliated with Rabbit Free Australia. </span></em></p>Rabbits destroy huge numbers of critical regenerating seedlings over more than half the continent. This has devastating flow-on effects for the rest of the ecosystem. So how do we control them?Pat Taggart, Adjunct Fellow, UNSW SydneyBrian Cooke, Adjunct Associate Professor, University of CanberraLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1302372021-08-18T14:59:28Z2021-08-18T14:59:28ZWhy I’m testing what invasive insects can see and the smells they like<figure><img src="https://images.theconversation.com/files/416764/original/file-20210818-27-1ghd4uc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">_Sirex noctilio_ is an invasive woodwasp that causes huge damage. Understanding what attracts it can help repel it.</span> <span class="attribution"><span class="source">Ludwig Eksteen</span></span></figcaption></figure><p>Dr Emmett Brown, Dr Victor Frankenstein and Dr Henry Jekyll are just three of the “crazy” scientists who populate fiction. Their methods were controversial and revolutionary – and I have always been especially drawn to the character of Dr Frankenstein, who was <a href="https://www.theguardian.com/books/gallery/2018/jan/13/mary-shelleys-frankenstein-in-charts">created by the English novelist Mary Shelley</a> in 1818. I am fascinated by how he used electricity to study and understand the living. Every movement, feeling or thought is the result of electrical current in our body.</p>
<p>As an electrophysiologist, I see myself as a modern, real version of Dr Frankenstein: I use electrodes to study and understand living organisms. Given the tragedy at the heart of Frankenstein, this may sound evil. But in fact, using ethical practices to insert electrodes into living creatures can help research in <a href="https://theconversation.com/study-shows-direct-manipulation-of-brain-can-reverse-effects-of-depression-62239">human health</a>, agriculture and forestry and create the path to greener ecology and conservation.</p>
<p>This sort of work also has enormous economic value because it can help reduce the damage done by invasive insects. A recent study <a href="https://www.nature.com/articles/ncomms12986">estimated</a> the losses and negative effects of invasive insects at US$70 billion annually. Other research suggests that insects destroy <a href="http://www.fao.org/3/av013e/av013e.pdf">one fifth of crops</a> produced annually worldwide. The figure can <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/crop-destruction">be higher</a> in developing countries.</p>
<p>How does inserting electrodes into insects tackle these problems? Simply, it helps scientists to understand, in the first instance, what attracts insects to different crops. It’s then possible to design ways to trap them. This is what <a href="https://www.nature.com/articles/s41598-021-95107-2">I’m doing</a> in <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0244943">my PhD research</a>, focused on an invasive woodwasp, <em><a href="http://entnemdept.ufl.edu/creatures/misc/wasps/Sirex_noctilio.htm">Sirex noctilio</a></em>. It kills pine trees and does major damage in the forestry sector worldwide. But by testing what colours and smells attract the insect, I have developed compounds I hope will trap and divert the wasps from pine trees.</p>
<h2>What attracts insects</h2>
<p>Pheromones are odours released by an insect which have a strong attractive effect on another insect’s behaviour. For example, male insects can smell a female willing to mate and are strongly attracted. </p>
<p>Insects are also attracted to what they perceive as a “beautiful” colour. As humans, we possess three pigments that absorb light, in the red, green and blue part of the visible spectrum. Colour blind people usually have a defective red pigment and struggle to differentiate colours such as green, orange and red. Most insects in the <em>Hymenoptera</em> order – like wasps, bees and hornets – possess three photoreceptors (for detecting green, blue and ultraviolet) in their eyes. This means they are less good at distinguishing warm colours than us, but they are able to see ultraviolets.</p>
<p>So, to trap these insects and prevent them from targeting crops or forestry plantations, scientists copy the insects’ natural pheromones. From this, and sometimes also synthesising colours that are pleasing to the insects, lures can be created to draw them away from particular crops or plant species.</p>
<p>By putting electrodes in the <em>Sirex noctilio’s</em> antennae, I am <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0244943">able to record</a> the electric current from those antennae to the brain and to visualise on a computer when the insect can smell a specific pheromone. This means I can see what the insect can smell. I can also insert very small electrodes into the insects’ eyes, <a href="https://www.nature.com/articles/s41598-021-95107-2">testing which colours they can see</a>.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/416765/original/file-20210818-23-1yh3xuk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/416765/original/file-20210818-23-1yh3xuk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/416765/original/file-20210818-23-1yh3xuk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/416765/original/file-20210818-23-1yh3xuk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/416765/original/file-20210818-23-1yh3xuk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/416765/original/file-20210818-23-1yh3xuk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/416765/original/file-20210818-23-1yh3xuk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The electro-retinography set-up used to examine the wasps.</span>
<span class="attribution"><span class="source">Author supplied</span></span>
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</figure>
<p>Armed with this information, we can now craft a selective “trap” – lures that keep the wasps away from the pine trees they usually target. These lures are a blend of a few pheromone compounds and the colours that are visible to the woodwasp. Once attracted in the trap, the invasive pest is killed and won’t do further damages to the area that needs to be protected.</p>
<h2>Huge benefits</h2>
<p>The next step will be to start field trials that put the compounds’ viability to the test.</p>
<p>Global research has already shown that pheromone traps of this nature, used in the field, can have tremendous positive effects. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4972084/">One study</a> followed the efficiency of such traps in citrus plantations in Brazil for 12 years. The authors estimated that up to 50% crop loss was prevented. This represented a benefit of between $2,655 and $6,548 for each dollar spent on the pheromone research.</p>
<p>Of course, my research is just one piece of a large puzzle. Scientists are trying a number of approaches to save crops and plantations around the world from invasive insects. These range from <a href="https://theconversation.com/nigeria-has-given-a-new-gm-cowpea-variety-the-go-ahead-why-it-matters-130304">transgenic crops</a> to <a href="https://theconversation.com/south-africa-investigates-sterilising-mosquitoes-in-anti-malaria-drive-106368">sterile insects</a>; from introducing a new species as a <a href="https://theconversation.com/how-biological-control-agents-could-get-invasive-stinging-wasps-to-buzz-off-71718">biological control agent</a> to creating <a href="https://theconversation.com/what-we-found-when-we-tested-a-botanical-pesticide-to-combat-locust-invasions-133105">new types of pesticides</a>. </p>
<p>What’s especially promising about creating pheromone and colour traps, however, is that they can be extremely targeted. More traditional methods of pest control, like spraying pesticide, can harm other, non-invasive species. But if we find that our traps are negatively affecting such species, we’ll remove them and try a more specific blend of compounds that we hope will only eradicate the wasps from pine plantations.</p>
<p><em>This article won the Science Communication Award in a competition hosted by The Conversation Africa and the DST-NRF Centre Of Excellence In Tree Health Biotechnology.</em></p><img src="https://counter.theconversation.com/content/130237/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Quentin Guignard does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Inserting electrodes into insects helps scientists understand what attracts these insects – and, stemming from that, how to trap them and protect crops.Quentin Guignard, PhD, Chemical & Visual Ecology, University of PretoriaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1593392021-04-30T03:58:26Z2021-04-30T03:58:26Z‘No one ever forgets living through a mouse plague’: the dystopia facing Australian rural communities, explained by an expert<figure><img src="https://images.theconversation.com/files/397977/original/file-20210430-20-o8pawo.JPG?ixlib=rb-1.1.0&rect=11%2C0%2C2576%2C1940&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="license">Author provided</span></span></figcaption></figure><p>Imagine constantly living with mice. Every time you open a cupboard to get linen, clothes or food, mice have been or are still there. When you go to sleep they run across your bed and, in the morning, your first job is to empty traps filled with dead mice. And the stench of dead mice fill the streets.</p>
<p>Even the cats and dogs get sick of mice and stop chasing them. </p>
<p>This is the dystopian reality for many towns as, over recent months, mouse numbers in northern NSW and southern Queensland have risen to plague proportions, devastating summer crops and fodder storages. One farmer told me he’s removing 100 dead mice from his swimming pool each night.</p>
<p>This week, for example, <a href="https://www.abc.net.au/news/rural/2021-04-30/mouse-poo-contamination-havoc-for-sorghum-farmers-exports/100104540">truckloads of sorghum</a> from Southern Queensland farms have been rejected from sale after mouse droppings were discovered. This means loads of grain need to be cleaned before they’re suitable for sale.</p>
<p>No one ever forgets living through a mouse plague. </p>
<p>One of the largely unquantified repercussions of mice is the <a href="https://www.abc.net.au/news/2021-04-26/mouse-plague-impacting-nsw-residents-mental-health/100091634">social and mental health impact</a> on farmers, their families and rural communities — places only just starting to recover from the recent, devastating drought. </p>
<p>I work with scientists and rural communities to reduce the impact of mice. So, with no end to the plague in sight, let’s look at the issue in more detail.</p>
<h2>Mice outbreaks in Australia</h2>
<p>The <a href="https://doi.org/10.1111/j.1095-8312.2005.00458.x">earliest accounts</a> of mouse outbreaks in Australia are from the late 1800s, after the house mouse, <em>Mus musculus</em>, was likely introduced in the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3236204/">late 1700s</a> as stowaways with the First Fleet. <a href="https://www.cabi.org/isc/FullTextPDF/2017/20173377647.pdf">Similar plagues</a> are uncommon in other countries — even though mice are found worldwide — as favourable climates lead to lots of food and shelter, which sustain high mouse populations in Australia.</p>
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<p>Outbreaks like we’re seeing now tend to follow a run of dry years. The house mouse is very well adapted to live in Australian conditions, and they can survive through protracted dry periods and thrive when there’s lots of food and moisture. While often not conspicuous, they’re present in most environments — all the time.</p>
<p>As climatic conditions become favourable for crop production, they’re also favourable for mouse breeding. And mice reproduce alarmingly fast. </p>
<p>They start breeding at six-weeks old and give birth to a litter of six to ten pups every 19 to 21 days after that. After giving birth to one litter, females can immediately fall pregnant with the next litter, meaning there’s no break in the production of offspring. </p>
<p>In good seasons, when the rate of survival is high, the rate of population increase is dramatic. A single pair of mice can give rise to <a href="https://www.dpi.nsw.gov.au/biosecurity/vertebrate-pests/pest-animals-in-nsw/mice/mouse-management">500 mice</a> in a breeding season. This year, the breeding season has lasted through summer and into autumn, as the weather has been milder with lots of rain.</p>
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<h2>Desperate times, desperate measures</h2>
<p>Mouse outbreaks or plagues occur across the cropping zone — the extensive area where crops are grown in Australia — approximately every five years. However major outbreaks like the one we’re experiencing today are less frequent. </p>
<p>In some towns across the cropping zone, the smell of dead and decomposing mice is becoming a significant problem in shops, rubbish bins and under buildings and homes, where mice that have been baited have gone to die.</p>
<p>And the outbreak is growing. I’m getting reports from farmers of high mouse numbers from other parts of the cropping zone, through southern NSW, Victoria and South Australia. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/397986/original/file-20210430-23-tqd0k9.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A haystack with a blue tarp over it" src="https://images.theconversation.com/files/397986/original/file-20210430-23-tqd0k9.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/397986/original/file-20210430-23-tqd0k9.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/397986/original/file-20210430-23-tqd0k9.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/397986/original/file-20210430-23-tqd0k9.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/397986/original/file-20210430-23-tqd0k9.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/397986/original/file-20210430-23-tqd0k9.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/397986/original/file-20210430-23-tqd0k9.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">1,600 bales of hay, completely decimated by mice.</span>
<span class="attribution"><span class="source">Adam Macrae</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p><a href="https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1005&context=nwrchumanconflicts">Mice can cause damage</a> during all stages of crop growth, and they don’t limit themselves to cereals. Farmers have reported significant damage in canola, lentils and other pulse crops. Likewise, mice removing freshly sown seed, browsing shoots and feeding on developing heads and seed pods all reduce crop yield. </p>
<p>Mice also cause <a href="https://www.graincentral.com/markets/feedgrain-focus-quality-issues-impact-north/">significant damage</a> to on-farm storages of grain and fodder. Contamination of grain with mouse faeces can lead to grain distributors and export markets rejecting produce (such as with sorghum in Southern Queensland). </p>
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Read more:
<a href="https://theconversation.com/how-to-know-if-were-winning-the-war-on-australias-fire-ant-invasion-and-what-to-do-if-we-arent-121367">How to know if we’re winning the war on Australia’s fire ant invasion, and what to do if we aren't</a>
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<p>This year has been so bad, farmers say they’re giving up on efforts to control mice with bait, and instead ploughing their summer crops back into the ground. Other desperate measures include burying entire haystacks to protect them from total decimation by mice. </p>
<p>The cotton industry, rarely impacted by mice, has even sought an <a href="https://cottonaustralia.com.au/assets/general/Biosecurity/PER90579-A2005618.pdf">emergency permit</a> to allow control of mice in cotton crops using zinc phosphide baits, the only approved chemical control measure for mice in broad-scale agriculture in Australia.</p>
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<h2>So how does this horror end?</h2>
<p>The drivers for the end of a mouse outbreak are not well understood. <a href="https://link.springer.com/article/10.1007/s00442-020-04810-w">It’s thought</a> a combination of high numbers, food running short and disease leads to mice turning on each other, eating sick and weak animals and offspring, resulting in a dramatic crash in the population. Farmers, in previous outbreaks, have reported mice disappearing almost overnight.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/397978/original/file-20210430-13-kehlu6.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/397978/original/file-20210430-13-kehlu6.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/397978/original/file-20210430-13-kehlu6.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/397978/original/file-20210430-13-kehlu6.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/397978/original/file-20210430-13-kehlu6.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/397978/original/file-20210430-13-kehlu6.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/397978/original/file-20210430-13-kehlu6.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/397978/original/file-20210430-13-kehlu6.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">CSIRO is developing strategies to reduce the impact of mice in agriculture.</span>
<span class="attribution"><span class="source">Sharon Watt</span>, <span class="license">Author provided</span></span>
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<p>CSIRO, with the support of the Grains Research and Development Corporation, <a href="https://grdc.com.au/resources-and-publications/resources/mouse-control">is working on</a> developing a range of new ways to reduce the impact of mice in crop production systems. Key focuses include monitoring populations to make predictions about future outbreaks and developing of better predictive models. </p>
<p>We’re also investigating how current cropping practices influence mouse behaviour and their population dynamics. This will help us assess potential new control strategies, develop more effective baiting procedures, and consider the potential of future genetic control technologies. </p>
<p>Still, the introduced house mouse will be an ongoing problem in Australian farms and rural communities for years to come. We must urgently find ways to reduce the economic and social impact of mice, not only for the sustainable production of crops, but also for the mental well-being of rural communities.</p>
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Read more:
<a href="https://theconversation.com/shy-rodents-may-be-better-at-surviving-eradications-but-do-they-pass-those-traits-to-their-offspring-146924">Shy rodents may be better at surviving eradications, but do they pass those traits to their offspring?</a>
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<p class="fine-print"><em><span>Steve Henry receives funding from the Grains Reserach Develpment Corperation. </span></em></p>Imagine constantly living with mice. When you go to sleep they run across your bed, the stench of dead mice fills the street. As an expert on mouse outbreaks, let’s look at the issue in more detail.Steve Henry, Research Officer, CSIROLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1478382020-12-31T20:19:13Z2020-12-31T20:19:13ZGreen buildings can bring fresh air to design, but they can also bring pests<p>Throughout the world architects are designing green buildings, whether it’s in their sustainable construction, environmentally friendly operation or actually green by style.</p>
<p>It’s broadly titled <a href="https://www.britannica.com/science/biophilia-hypothesis">biophilia</a>, connecting people with nature, and it can lead to some creative and innovative designs.</p>
<p>But now we are finding that literally greening the world — by covering building walls and roofs with vegetation — can also come with some unexpected problems.</p>
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Read more:
<a href="https://theconversation.com/greening-our-grey-cities-heres-how-green-roofs-and-walls-can-flourish-in-australia-139478">Greening our grey cities: here's how green roofs and walls can flourish in Australia</a>
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<h2>A bug’s high life</h2>
<p>In the Chinese city of Chengdu, a vast green experimental housing estate of 826 apartments was constructed where people can live in a vertical forest with every open space and balcony containing live vegetation.</p>
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<p>Trouble is they must share the plants with a scourge of mosquitoes and other bugs. Most apartments in the <a href="http://www.skyscrapercenter.com/building/qiyi-city-forest-garden-tower-4/39567">Qiyi City Forest Gardens</a> development were sold by April 2020, but six months later <a href="https://www.globaltimes.cn/content/1200404.shtml">only a handful</a> of families had <a href="https://newsinfo.inquirer.net/1335843/plants-bugs-seize-china-apartments">reportedly</a> moved in.</p>
<p>The towers were built in 2018 and plants were provided to reduce noise and <a href="https://www.globaltimes.cn/content/1031741.shtml">clean up pollution</a>. But the plants thrived, while sales moved slowly, and no one was clipping the greenery to keep it in control. </p>
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Read more:
<a href="https://theconversation.com/unbuilding-cities-as-high-rises-reach-their-use-by-date-129002">Unbuilding cities as high-rises reach their use-by date</a>
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<p>Now mostly empty balconies have cascading branches of plants overtaking space, blocking windows.</p>
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<p>It might not help that Chengdu and its population of 16.3 million people are located in Sichuan, central China, which is humid and semi-tropical, a perfect environment for fast-breeding mossies.</p>
<p>But a slow uptake, with tenants slow to move in, made the problem worse as the plants subsumed their buildings.</p>
<h2>Some vertical vegetation living success</h2>
<p>Other green projects across the globe have avoided this particular problem, so far.</p>
<p>Milan’s <a href="https://www.stefanoboeriarchitetti.net/en/project/vertical-forest/">Bosco Verticale</a> (Vertical Forest) was designed by <a href="https://www.stefanoboeriarchitetti.net/en/stefano-boeri-biography/">Stefano Boeri</a> and botanist Laura Gatti. </p>
<p>They <a href="https://www.stefanoboeriarchitetti.net/en/project/vertical-forest/">reportedly</a> spent long hours selecting suitable vegetation, a variety of 800 trees, 5,000 shrubs and 15,000 plants, which would suit their location and the Milanese climate.</p>
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<strong>
Read more:
<a href="https://theconversation.com/australian-cities-are-lagging-behind-in-greening-up-their-buildings-97088">Australian cities are lagging behind in greening up their buildings</a>
</strong>
</em>
</p>
<hr>
<p>Their plan was to improve air quality in the city via the green facades, and residents have embraced the concept, which appears to be where Qiyi City Forest has gone wrong.</p>
<p>In Chengdu, maintenance and care of the plantings is almost non-existent, so no truly symbiotic relationship between accommodation and human occupier has formed as part of biophilic living. As is nature’s way, the non-human occupiers (the bugs) are winning.</p>
<h2>Gardens need a gardener</h2>
<p>US landscape architect Daryl Beyers, from the New York Botanical Garden, <a href="https://archive.curbed.com/2020/9/18/21445069/qiyi-city-forest-garden-mosquitoes-chengdu">says</a> the Chengdu setup didn’t work partly as a result of bad design.</p>
<p>In Chengdu’s humid climate and clammy monsoons, stagnant water collects in planters which are not properly drained, and mosquitoes breed in these.</p>
<p>Beyers adds: </p>
<blockquote>
<p>They [the developers] didn’t think about the maintenance […] You can’t have a garden without a gardener.</p>
<p>They were touting it as a manicured garden outside on your deck. If it’s manicured, someone has to do the manicuring.</p>
</blockquote>
<p>The idea of fully manicured vegetation on balconies only works if the plants are cared for regularly. <a href="https://archive.curbed.com/2020/9/18/21445069/qiyi-city-forest-garden-mosquitoes-chengdu">Apparently</a>, gardeners attend Qiyi City just four times a year to maintain the plants, but they require weekly care.</p>
<h2>Sydney’s green space on the up</h2>
<p><a href="https://www.centralparksydney.com/">One Central Park</a> apartments in Sydney, by <a href="http://www.jeannouvel.com/projets/one-central-park/">French architect Jean Nouvel</a>, takes on a green mantle with plants covering most of its walls and balconies.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/371692/original/file-20201127-21-5zp0l4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Tall buildings covered in green plants" src="https://images.theconversation.com/files/371692/original/file-20201127-21-5zp0l4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/371692/original/file-20201127-21-5zp0l4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/371692/original/file-20201127-21-5zp0l4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/371692/original/file-20201127-21-5zp0l4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/371692/original/file-20201127-21-5zp0l4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=425&fit=crop&dpr=1 754w, https://images.theconversation.com/files/371692/original/file-20201127-21-5zp0l4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=425&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/371692/original/file-20201127-21-5zp0l4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=425&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">One Central Park is the world’s largest vertical gardens.</span>
<span class="attribution"><span class="source">Shutterstock/SAKARET</span></span>
</figcaption>
</figure>
<p><a href="https://www.verticalgardenpatrickblanc.com/realisations/sydney/one-central-park-sydney">French botanist Patrick Blanc</a> selected the plants on the building for their capacity for healthy growth and suitability to the Sydney habitat.</p>
<p>By <a href="https://www.arup.com/projects/one-central-park">using</a> acacias (wattles) and poa (grasses) on upper levels and goodenia (hop bush) and viola (native violet) lower down, the vegetation is attuned to its place and growing successfully.</p>
<p>More than 1,100 square metres of walls support many species of plants, most of them native to Sydney. They are at home with the local climate and seasons. The plants can withstand hot, dry and windy Australian summers and have survived since 2014.</p>
<h2>How to green your buildings</h2>
<p>Green buildings are necessary for the environment. We need to redress the loss of our natural resources and their benefits, and green buildings can do that by adopting appropriate design, energy efficiencies, renewable materials and green technologies.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-third-of-our-waste-comes-from-buildings-this-ones-designed-for-reuse-and-cuts-emissions-by-88-147455">A third of our waste comes from buildings. This one's designed for reuse and cuts emissions by 88%</a>
</strong>
</em>
</p>
<hr>
<p>Central Park’s success could be emulated at Chengdu, by tracing back the original design intent and adopting a workable maintenance and management plan. </p>
<p>The lessons from both projects indicate that proper planning and appropriate selection of vegetation, which is then fed and watered by applicable technology, will yield a proficient green building. </p>
<p>People feel comfort living with nature, and a vertical garden gives those in high-rise towers a chance to share that comfort. But with the benefits come responsibilities. </p>
<p>The clue here is that a faithfully biophilic building must be appropriate for use. That means appropriate in terms of the place, natural resources, local climate and the people who must manage and occupy the natural surroundings.</p><img src="https://counter.theconversation.com/content/147838/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Norman Day does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>People love to connect with nature and that’s possible with vertical gardens on high-rise developments. But gardens need a gardener to keep things under control.Norman Day, Lecturer in Architecture, Practice and Design, Swinburne University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1469242020-11-10T04:43:14Z2020-11-10T04:43:14ZShy rodents may be better at surviving eradications, but do they pass those traits to their offspring?<figure><img src="https://images.theconversation.com/files/368459/original/file-20201110-23-axcb4l.jpg?ixlib=rb-1.1.0&rect=0%2C14%2C3304%2C2181&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Rodents such as house mice (<em>Mus musculus</em>) aren’t just pests at home, they can cause serious damage to native ecosystems.</p>
<p>Lord Howe Island, for example, harboured <a href="https://www.abc.net.au/news/2019-06-11/rat-infestation-on-lord-howe-island-splits-residents/11180624?nw=0">up to</a> 150,000 introduced rats and 210,000 introduced mice that wrought havoc on the island’s native wildlife, before an intensive eradication effort was carried out. It was declared a <a href="https://www.australiangeographic.com.au/news/2020/01/win-for-endangered-lord-howe-island-woodhens/">success</a> earlier this year, although monitoring for survivors will continue. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/invasive-predators-are-eating-the-worlds-animals-to-extinction-and-the-worst-is-close-to-home-64741">Invasive predators are eating the world's animals to extinction – and the worst is close to home</a>
</strong>
</em>
</p>
<hr>
<p>But emerging research suggests the success of eradicating pests may depend on the personality of individual animals within a species. </p>
<p>Bolder, more active, aggressive or social individuals are more likely to interact with baits, traps or <a href="https://academic.oup.com/beheco/article/28/6/1504/4210926">new objects and foods</a>. As a result, they can be <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/j.0030-1299.2008.16567.x?casa_token=azpKp0d5V6QAAAAA%3ABQVuqWz3O2z3mdRDdF1Wnywx_lYNwjVQ5HgIhSzbYBqUFm_EiNnwbGJbSIMh0FRxafMbP6RpVZRP1DazTg">removed quickly</a>.</p>
<p>On the other hand, shyer or less active individuals <a href="https://www.sciencedirect.com/science/article/pii/S000334721200053X?casa_token=c-6mOegvXv4AAAAA:VxYGj3pXIzKPCzbSkB_WhJ_6rSTfMGgZybqSiZoy6nlwGqkSJQ4nX0QrdlFlkNUUVBwYAHKyAfg">can take longer</a> to be caught.</p>
<p>Why is this so important? Well for starters, animals that actively avoid eradication will breed and repopulate. </p>
<p>If the personality traits of these survivors are reflected in all, or even most, offspring then we could be facing a pest population that is incredibly difficult to remove. This is what <a href="https://esajournals.onlinelibrary.wiley.com/doi/pdf/10.1002/eap.2247?casa_token=6xKgF7qKsEoAAAAA:3PuCTo5UHy2NxYISJb1MvG1OexcF33cByxDc4mHGpO1DrJQeaR_jio9M5u-kAov5vf_Vik6Kei5ec2EpHg">our new research</a> aimed to find out. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/368474/original/file-20201110-20-10g4b5n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Aerial view of Lord Howe Island" src="https://images.theconversation.com/files/368474/original/file-20201110-20-10g4b5n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/368474/original/file-20201110-20-10g4b5n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=419&fit=crop&dpr=1 600w, https://images.theconversation.com/files/368474/original/file-20201110-20-10g4b5n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=419&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/368474/original/file-20201110-20-10g4b5n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=419&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/368474/original/file-20201110-20-10g4b5n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=527&fit=crop&dpr=1 754w, https://images.theconversation.com/files/368474/original/file-20201110-20-10g4b5n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=527&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/368474/original/file-20201110-20-10g4b5n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=527&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Islands, such as Lord Howe Island off NSW, are refuges for a range of wildlife often not found anywhere else in the world.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>When eradication efforts fail</h2>
<p>Australia is home to more than <a href="https://invasives.org.au/our-work/islands/">8,300 islands</a> that provide refuge for unique species often found nowhere else in the world, including species now extinct on the mainland. </p>
<p>Introduced mammalian pests, particularly rodents, are huge threats to island species, which often evolve without predators. They don’t recognise these introduced mammals as a threat, making them easy targets. </p>
<p>For example, <a href="https://www.cambridge.org/core/journals/antarctic-science/article/evidence-of-mouse-attacks-on-albatross-chicks-on-subantarctic-marion-island/FA02807B3011973762C0BFE418CB3B17">a 2010 study</a> observed house mice literally eating albatross chicks alive on Marion Island near Antarctica. Neither the chicks nor parents showed any defensive or escape behaviour. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/feral-animals-are-running-amok-on-australias-islands-heres-how-to-stop-them-64307">Feral animals are running amok on Australia's islands – here's how to stop them</a>
</strong>
</em>
</p>
<hr>
<p>Eradicating introduced pest species is the ultimate solution if we want to protect native island ecosystems.</p>
<p>But eradication efforts are only effective if every animal in a population is eliminated. While most failed efforts likely go unreported, <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/mam.12190">on average</a>, 11% of eradication attempts for rodents fail. For house mice in particular, failure rates can be as high as 75%. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/368472/original/file-20201110-21-yjd8cv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Nesting albatross on Marion Island" src="https://images.theconversation.com/files/368472/original/file-20201110-21-yjd8cv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/368472/original/file-20201110-21-yjd8cv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/368472/original/file-20201110-21-yjd8cv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/368472/original/file-20201110-21-yjd8cv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/368472/original/file-20201110-21-yjd8cv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/368472/original/file-20201110-21-yjd8cv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/368472/original/file-20201110-21-yjd8cv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Nesting albatross on Marion Island, where chicks were found to be eaten by introduced house mice.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>When efforts fail, pest populations quickly bounce back. <a href="https://royalsocietypublishing.org/doi/full/10.1098/rsos.160110">One study</a> in 2016 found around 50 rats survived an eradication attempt by avoiding baits on Henderson Island in the South Pacific. Within only two years, the population had exploded into roughly 75,000 animals. </p>
<h2>Developing personality traits</h2>
<p>So if animal behaviour influences if an individual enters a trap or takes a bait, how much of the parent personality is reflected in the offspring? </p>
<p>If you’ve thought about the similarity between parents and children — in both human and our animal companions — then you know some offspring behave just like their parents, while others are very different. </p>
<p>Personality traits develop through a combination of <a href="https://academic.oup.com/beheco/article/28/3/732/3007699">experience</a>, <a href="https://royalsocietypublishing.org/doi/abs/10.1098/rsbl.2013.0120">learning from parents</a> and <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1469-185X.2007.00010.x?casa_token=ZpAGu_8jKd8AAAAA:viBLwqpK3Q1uHxxlbsPi3SHIzsAbH-Yn57NLbPwWAMV8uu7SwVFykF3BFY_Jiv3HPvHNjVPA8VKE9pHrVA">genetic inheritance</a>. </p>
<p>Humans have selectively bred domestic animals, including <a href="https://www.sciencedirect.com/science/article/pii/S0168159102001211?casa_token=CuqvJSUKeAUAAAAA:aJD_expxE9bjpdOxWCacZnYlvoAKYrQHDxFytlE0NwJKHyIiaykzymbXRamIegzC5ebEzgObA8g">dogs</a>, <a href="https://academic.oup.com/jas/article-abstract/73/8/2249/4632873">cattle</a> and <a href="https://psycnet.apa.org/doiLanding?doi=10.1037%2F0735-7036.118.4.434">horses</a> for preferred personality traits, such as docility. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/understanding-dog-personalities-can-help-prevent-attacks-120224">Understanding dog personalities can help prevent attacks</a>
</strong>
</em>
</p>
<hr>
<p>And studies on laboratory animals, including <a href="https://www.sciencedirect.com/science/article/pii/S0376635705002330?casa_token=gTgO7AuXJasAAAAA:Lj3ROxHhC0C5K6FxIuFB4yqqE-76mwlTlgQwkTEws4bdqLwTXSflixFPyw5hrFe6JxF2htwpfIM">mice</a> and <a href="https://link.springer.com/article/10.1007/BF01065624">chicks</a>, have found selecting for preferred traits in parents can lead to these traits being strongly expressed in the offspring within a single generation. </p>
<p>However, can this immediate generational response occur in wild populations?</p>
<h2>What our study did</h2>
<p>To begin untangling this web, we used house mice as a model species and mimicked a failed eradication, where residual mice (the would-be survivors) were selected for biased personality traits. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/368463/original/file-20201110-13-z8qmre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/368463/original/file-20201110-13-z8qmre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/368463/original/file-20201110-13-z8qmre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1067&fit=crop&dpr=1 600w, https://images.theconversation.com/files/368463/original/file-20201110-13-z8qmre.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1067&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/368463/original/file-20201110-13-z8qmre.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1067&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/368463/original/file-20201110-13-z8qmre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1341&fit=crop&dpr=1 754w, https://images.theconversation.com/files/368463/original/file-20201110-13-z8qmre.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1341&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/368463/original/file-20201110-13-z8qmre.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1341&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A mouse in our study caught in a trap.</span>
<span class="attribution"><span class="source">Kyla Johstone</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>After catching wild house mice, we tested for personality traits by filming their behaviour in a modified open-field arena. Mice that moved frequently between compartments and into light compartments (which present a risky scenario to a small nocturnal rodent) were considered to be “high active-bold” individuals. </p>
<p>Based on their behaviour, we then grouped individual mice into populations: high active-bold individuals, low active-bold (shy) individuals and intermediate individuals. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-to-know-if-were-winning-the-war-on-australias-fire-ant-invasion-and-what-to-do-if-we-arent-121367">How to know if we’re winning the war on Australia’s fire ant invasion, and what to do if we aren't</a>
</strong>
</em>
</p>
<hr>
<p>To closely mimic wild conditions, we released the populations into large outdoor yards and left the mice to breed for one generation. After recapturing every single mouse from the yards, we tested the offspring for the same personality traits.</p>
<h2>The good news</h2>
<p>Interestingly, although the parent populations had strong personality biases, there was a broad spectrum of personality among offspring of every population. In other words, bold mice didn’t necessarily produce bold offspring, nor shy mice, shy offspring.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/368467/original/file-20201110-15-14yteev.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A juvenile mouse" src="https://images.theconversation.com/files/368467/original/file-20201110-15-14yteev.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/368467/original/file-20201110-15-14yteev.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1066&fit=crop&dpr=1 600w, https://images.theconversation.com/files/368467/original/file-20201110-15-14yteev.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1066&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/368467/original/file-20201110-15-14yteev.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1066&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/368467/original/file-20201110-15-14yteev.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1340&fit=crop&dpr=1 754w, https://images.theconversation.com/files/368467/original/file-20201110-15-14yteev.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1340&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/368467/original/file-20201110-15-14yteev.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1340&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A juvenile mouse from our study. Mice born from shy parents didn’t necessarily have shy personalities.</span>
<span class="attribution"><span class="source">Kyla Johnstone</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>This was reassuring news. However, demonstrating there’s no generational bias in house mice doesn’t mean it can’t arise elsewhere or in other species. And our study is an important stepping stone to explore this concept in other invasive species and over multiple generations. </p>
<p>Still, for house mouse eradications at least, our findings suggest that, even if all surviving individuals had a similar personality, by the next generation a broad spectrum of personality should emerge again. </p>
<p>This suggests we’re unlikely to be faced with a population that’s impossible to remove, and can focus on improving success rates for these difficult-to-remove individuals and species.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/compassionate-conservation-just-because-we-love-invasive-animals-doesnt-mean-we-should-protect-them-144945">'Compassionate conservation': just because we love invasive animals, doesn't mean we should protect them</a>
</strong>
</em>
</p>
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<img src="https://counter.theconversation.com/content/146924/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kyla Johnstone received funding from The Holsworth Wildlife Research Endowment and the Paddy Pallin Foundation. </span></em></p><p class="fine-print"><em><span>Peter Banks receives funding from the Australian Research Council, Northern Beaches Council and Landcare Research, and is a council member of the Royal Zoological Society of New South Wales</span></em></p><p class="fine-print"><em><span>Clare McArthur does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>If all, or even most, offspring of the survivors are shy, we could be facing an introduced pest population that is incredibly difficult to remove.Kyla Johnstone, PhD candidate, University of SydneyClare McArthur, Professor, University of SydneyPeter Banks, Professor of Conservation Biology, School of Life and Environmental Sciences, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1435272020-08-13T15:57:19Z2020-08-13T15:57:19ZThe next invasion of insect pests will be discovered via social media<figure><img src="https://images.theconversation.com/files/351791/original/file-20200807-16-16ii82l.jpg?ixlib=rb-1.1.0&rect=135%2C105%2C4865%2C3223&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The European firebug was first discovered in North America in Utah in 2008 and has quickly expanded its range. </span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>In mid-July, Reddit user erako <a href="https://www.reddit.com/r/whatsthisbug/comments/hsltbh/weird_beetle_found_in_mississauga_on/?sort=new">shared a photo</a> of some exotic-looking insects, curious as to what they were.</p>
<p>The insects seemed out of place for Mississauga, Ont. — they were bright red, covered with black bands and spangled with white stars. </p>
<p>The original poster couldn’t have anticipated the panicked messages and emergency emails that would ripple out across the internet and through multiple Canadian government agencies in response.</p>
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<h2>Case of mistaken identity</h2>
<p>The insect was swiftly and correctly identified by the Reddit community as the spotted lanternfly (<em>Lycorma delicatula</em>), an invasive insect that has been spreading outward from southern Pennsylvania since its accidental introduction in 2014. </p>
<p>Across Canada, entomologists, conservationists, farmers and foresters have anxiously watched for it. This pest feeds on the sap of more than 70 species of trees, shrubs and vines, robbing the plant of energy and providing opportunities for fungal diseases to colonize. Costs associated with lost crops, damaged plants and pest control can be substantial, <a href="https://doi.org/10.1002/ps.5619">with yearly harvests or entire orchards being lost</a>.</p>
<p>Fortunately, it was a case of mistaken location: the photo had originated in New Jersey, not Mississauga. For the time being, Canada has avoided another insect invader. </p>
<p>The incident, however, served as a successful test of the important role social media and a whole nation of community scientists are playing in the detection and identification of introduced species.</p>
<h2>Using the power of social media for natural history</h2>
<p>People of all ages are taking to social media to connect with other naturalists. From <a href="https://www.reddit.com/r/whatsthisbug/">Whatsthisbug on Reddit</a> (which boasts 245,000 members), to the <a href="https://twitter.com/i/lists/994044327922827264">thousands of active entomologists on Twitter</a>, to the hundreds of groups dedicated to insect identification on Facebook such as <a href="https://www.facebook.com/groups/TheEntomologyGroup/about/">Entomology</a> (146,000 members) and <a href="https://www.facebook.com/groups/Insect.Identification/">Insect Identification</a> (62,000 members), social media are enabling biodiversity conversations. </p>
<p>New scientifically unnamed species — from fungi to flowers to insects — are now regularly found via <a href="https://doi.org/10.3897/mycokeys.67.51811">Twitter</a>, <a href="https://doi.org/10.11646%2Fphytotaxa.220.3.4">Facebook</a> and <a href="https://doi.org/10.3897/zookeys.214.3220">Flickr</a>.</p>
<p>Additionally, we are learning more about species familiar to us. Species’ ranges (the area where a species is found) and life histories are being monitored by a global community emboldened and enabled to share their findings for the world to enjoy. Scientists are actively participating as well, creating programs <a href="https://twitter.com/RecluseOrNot">to answer questions about spiders</a> and recruit volunteers to <a href="https://www.bumblebeewatch.org/">find bumblebees</a> or <a href="http://healthyforestpartnership.ca/budworm-tracker/">collect forest pests</a>. </p>
<p>Alongside the big social media networks, a website that has quickly established itself for natural history documentation is <a href="https://www.inaturalist.org">iNaturalist</a>. A joint initiative of the California Academy of Sciences and the National Geographic Society, iNaturalist has become a world-leading resource that combines observational data with artificial intelligence and community expertise to bring natural history into the digital age. </p>
<h2>iNaturalists are already on the case</h2>
<p>iNaturalist is already helping identify invasive urban landscape pests in Ontario. The European firebug (<em>Pyrrhocoris apterus</em>), a brightly coloured bug that feeds on linden trees and hibiscus plants, was <a href="https://journal.lib.uoguelph.ca/index.php/eso/article/view/4406">first identified in Canada by Paula Oviedo Rojas</a>, a student at the University of Guelph, in her Etobicoke, Ont., backyard in 2017. A year later across town, backyard naturalist <a href="https://www.inaturalist.org/blog/18683-an-invasive-moth-is-recorded-in-ontario-canada-for-the-first-time-observation-of-the-week-9-9-18">Karen Yukich discovered the box tree moth</a> (<em>Cydalima perspectalis</em>) in her garden. While this moth has been causing significant damage to boxwood shrubs across Europe, this observation marked its first known record in North America. </p>
<p>Both species have since been observed spreading across the Greater Toronto Area by iNaturalists whose observations are helping researchers understand how invasive species move through urban landscapes.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/351220/original/file-20200805-290-1pg44mj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The European Firebug (Pyrrhocoris apterus) and Box Tree Moth (Cydalima perspectalis)" src="https://images.theconversation.com/files/351220/original/file-20200805-290-1pg44mj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/351220/original/file-20200805-290-1pg44mj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=238&fit=crop&dpr=1 600w, https://images.theconversation.com/files/351220/original/file-20200805-290-1pg44mj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=238&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/351220/original/file-20200805-290-1pg44mj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=238&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/351220/original/file-20200805-290-1pg44mj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=299&fit=crop&dpr=1 754w, https://images.theconversation.com/files/351220/original/file-20200805-290-1pg44mj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=299&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/351220/original/file-20200805-290-1pg44mj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=299&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">These introduced urban plant pests are examples of how community scientists are helping scientists and government agencies detect and track invasive species via social media; a) European firebug (<em>Pyrrhocoris apterus</em>), b) box tree moth (<em>Cydalima perspectalis</em>).</span>
<span class="attribution"><span class="source">(Morgan Jackson, Karen Yukich)</span></span>
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</figure>
<h2>Natural history in the digital age</h2>
<p>As natural history goes digital, it is experiencing a renaissance. Natural history — one of biology’s oldest disciplines — is often trivialized as an outdated pastime, and not a true scientific discipline, <a href="https://www.americanscientist.org/article/why-ecology-needs-natural-history">even though it underpins much of modern biology</a>.</p>
<p>The proliferation of smart phones means many people have an encyclopedia of knowledge, a high-resolution digital camera and GPS in their pockets. The curious are being transformed into community scientists who contribute vital data and observations from their local parks, backyards and city streets.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/351161/original/file-20200804-24-ydb4y9.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/351161/original/file-20200804-24-ydb4y9.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/351161/original/file-20200804-24-ydb4y9.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=459&fit=crop&dpr=1 600w, https://images.theconversation.com/files/351161/original/file-20200804-24-ydb4y9.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=459&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/351161/original/file-20200804-24-ydb4y9.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=459&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/351161/original/file-20200804-24-ydb4y9.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=577&fit=crop&dpr=1 754w, https://images.theconversation.com/files/351161/original/file-20200804-24-ydb4y9.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=577&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/351161/original/file-20200804-24-ydb4y9.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=577&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Four invasive insect pests to look out for: a) The egg-cases of the woolly hemlock adelgid (<em>Adelges tsugae</em>); b) the spotted lanternfly (<em>Lycorma delicatula</em>); c) the khapra beetle (<em>Trogoderma granarium</em>); d) the Asian long-horned beetle (<em>Anoplophora glabripennis</em>).</span>
<span class="attribution"><span class="source">(Nicholas_T/flickr; Walthery/Wikimedia Commons; USDA /Public Domain; Arp/Wikimedia Commons)</span></span>
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<h2>Become an invasive species detective</h2>
<p>Many hands make light work, the saying goes. And many naturalists make early detections more likely. </p>
<p>The Canadian government is constantly on the lookout for potential new arrivals that can harm natural resources or decimate crops, and social media-connected community scientists are swiftly becoming our first line of defence. Major pests like the <a href="https://www.inspection.gc.ca/plant-health/plant-pests-invasive-species/insects/hemlock-woolly-adelgid/fact-sheet/eng/1325616708296/1325618964954">wooly hemlock adelgid</a>, the <a href="https://www.inspection.gc.ca/plant-health/plant-pests-invasive-species/insects/spotted-lanternfly/eng/1433365581428/1433365581959">spotted lanternfly</a>, the <a href="https://www.inspection.gc.ca/plant-health/plant-pests-invasive-species/insects/khapra-beetle/fact-sheet/eng/1328541793480/1328541924086">khapra beetle</a> or the <a href="https://www.inspection.gc.ca/plant-health/plant-pests-invasive-species/insects/asian-longhorned-beetle/fact-sheet/eng/1447168284946/1447168408039">Asian long-horned beetle</a> are all likely targets for community detection. </p>
<p>So, as you move through your day, take a closer look at the insects and other organisms that share your environment. When something catches your attention, take a photograph and share it with the internet — your observation could be more significant than you may realize.</p><img src="https://counter.theconversation.com/content/143527/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Entomologists worried about invasive pests have thousands of curious community scientists posting their findings online — and identifying new species.Paul Manning, Postdoctoral Researcher, Faculty of Agriculture, Dalhousie UniversityMorgan Jackson, Postdoctoral Researcher in Entomology, McGill UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1406252020-06-17T20:04:34Z2020-06-17T20:04:34ZHuge locust swarms are threatening food security, but drones could help stop them<p>In recent months, food security concerns have emerged for nations across Africa, Asia and the Middle East, as swarms of desert locusts <a href="https://www.theguardian.com/global-development/2020/mar/20/locust-crisis-poses-a-danger-to-millions-forecasters-warn">wreak havoc</a> on crops.</p>
<p>While the same level of damage isn’t currently being felt in Australia, the threat of infestations extends to us too. But drone technology is offering up solutions.</p>
<h2>Not just a Biblical threat</h2>
<p>In January, the United Nations Food and Agriculture Organisation (FAO) <a href="http://www.fao.org/news/story/en/item/1258877/icode/">warned</a> rising locust numbers in the Horn of Africa presented an “extremely alarming and unprecedented threat” to food security and livelihoods. </p>
<p>According to the FAO, a swarm of about 40 million desert locusts can eat the <a href="http://www.fao.org/ag/locusts/en/info/info/faq/index.html#:%7E:text=A%20Desert%20Locust%20adult%20can,day%20as%20about%2035%2C000%20people.">same amount of food</a> in one day as about 35,000 people. Swarms <a href="http://www.fao.org/ag/locusts/oldsite/LOCFAQ.htm#q1">can be</a> as large as several hundred square kilometres, with as many as 80 million adults per square kilometre.</p>
<p>Countries <a href="https://www.theguardian.com/global-development/2020/jun/08/rolling-emergency-of-locust-swarms-decimating-africa-asia-and-middle-east#_=_">impacted</a> by infestations this year include Ethiopia, Kenya, Uganda, Somalia, India, Pakistan, Iran, Yemen, Oman and Saudi Arabia.</p>
<p>A review of records by the <a href="https://www.agriculture.gov.au/pests-diseases-weeds/locusts">Australian Plague Locust Commission</a> has reported eight large outbreaks in Australia since 1930. The FAO has <a href="https://www.aap.com.au/un-to-set-drones-on-east-africa-locusts/">encouraged</a> the use of drones to provide early warning systems that may help prevent locust outbreaks. </p>
<h2>Control with technology</h2>
<p>In nature, locusts are controlled by birds, spiders, parasitic flies and wasps – but these aren’t effective when numbers explode. </p>
<p>In Australia, locusts are generally controlled by aerial spraying of pesticides from light aircraft. One solution may be to destroy eggs by ploughing in crops or pastures, but there’s <a href="http://agriculture.vic.gov.au/agriculture/pests-diseases-and-weeds/pest-insects-and-mites/plague-locusts/fact-sheet-forestry-and-plantations">no conclusive data</a> on how effective this is.</p>
<p>Drones are now providing an innovative alternative to the more expensive use of light aircrafts. These aerial vehicles can be used to remotely sense areas, carry out pest surveillance and monitor crop growth.</p>
<p>They also allow for targeted pesticide application through atomiser sprayers that deliver a fine, even spray from liquid.</p>
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Read more:
<a href="https://theconversation.com/how-many-locusts-does-it-take-to-start-a-biblical-plague-just-three-49548">How many locusts does it take to start a biblical plague? Just three</a>
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<p>Each state and territory of Australia has been affected by plague locusts at some point in the past, with outbreaks having occurred in Queensland, New South Wales, Victoria, South Australia and Western Australia. The <a href="https://www.agriculture.gov.au/sites/default/files/documents/locust-Bulletin-April-2020.pdf">latest April</a> bulletin shows limited outbreaks in New South Wales. </p>
<p>There is a growing body of <a href="https://www.researchgate.net/publication/337826660_Drones_Innovative_Technology_for_Use_in_Precision_Pest_Management">research</a> on the use of drones for pest monitoring and management, with several Australian agricultural consultancy companies <a href="https://foresttech.events/how-drones-are-being-used-in-australia-to-make-farming-more-efficient/">offering</a> drone services for crop and soil monitoring. State and federal agricultural agencies also use drones for crop, disease and pest monitoring. </p>
<p>Understanding the movement of locusts helps determine the best way to control crop damage. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/342373/original/file-20200617-94060-1rwu0zx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Agriculture drones can be used to spray fertiliser and pesticide on crops.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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</figure>
<p>Last month marked the first time <a href="https://timesofindia.indiatimes.com/india/in-a-first-drone-used-to-clear-locust-swarms-in-chomu/articleshow/76053417.cms">drones were used</a> to clear swarms in Rajasthan, India. Spraying insecticides dispersed the insects into different areas. </p>
<p>Drones can also be used in the aftermath of infestations. For instance, recent outbreaks in Kenya have seen the use of drones for post-disaster mapping. <a href="https://reliefweb.int/report/kenya/east-africa-race-outsmart-locusts-drones-and-data">These maps</a>, along with satellite information, can provide more accurate assessments of the extent of crop loss.</p>
<p>On-ground <a href="https://www.techbriefs.com/component/content/article/tb/features/articles/33212">internet-connected sensors</a> with thermal and image processing capabilities could also potentially be used to monitor the spread of infestations. These could provide additional real-time monitoring to support satellite imagery.</p>
<h2>Some bugs remain</h2>
<p>There are limitations when it comes to using drones to tackle locust problems.</p>
<p>Drones don’t perform well in areas that are densely packed with locusts, due to damage to propellers. And while the technical specifications of drones have made rapid improvements over the past few years, they still only provide a limited load of insecticide for spraying.</p>
<p>The duration of flying time for drones is also usually <a href="https://3dinsider.com/long-range-drones/">less than an hour</a>. Flying drones requires a degree of expertise, and any commercial drone flying requires certification from the <a href="https://www.casa.gov.au/">Civil Aviation Safety Authority</a>.</p>
<h2>Small creature, big bite</h2>
<p>Locusts belong to the same order of insects as grasshoppers, katydids and crickets. Locusts are grasshoppers that develop “gregarious” behaviours and become more voracious as a result. </p>
<p>Grasshoppers can <a href="https://www.cam.ac.uk/research/news/a-brain-chemical-changes-locusts-from-harmless-grasshoppers-to-swarming-pests">become gregarious</a> and start to swarm due to an increase in chemical serotonin in their nervous system. This results in them going from individual walking grasshoppers to flying locusts. There are no clear differences between locusts and grasshoppers <a href="https://www.worldatlas.com/articles/what-is-the-difference-between-grasshoppers-and-locusts.html">other than behaviour</a>. </p>
<p>In Australia there are three main pest locust species: the Australian plague locust (<em>Chortoicetes terminifera</em>), the spur-throated locust (<em>Austracris guttulosa</em>) and the migratory locust (<em>Locusta migratoria</em>). Controlling these <a href="https://www.agric.wa.gov.au/pest-insects/australian-plague-locust-frequently-asked-questions">pests</a> is difficult when they travel in swarms. </p>
<p>Locust swarms can decimate swathes of crop in their way, <a href="http://agriculture.vic.gov.au/agriculture/pests-diseases-and-weeds/pest-insects-and-mites/plague-locusts/fact-sheet-vegetable-and-herbs#:%7E:text=The%20Australian%20plague%20locust%20prefers,%2C%20pasture%2C%20grapevines%20and%20trees.">consuming everything</a> from leaves and grains, to pastures and even trees.</p>
<p>With ongoing locust infestations, a rise in extreme weather events, and now COVID-19, the struggles faced by farmers the world over are compounded. Improving current technologies and finding new ways to innovate may help ease this burden in the coming years.</p>
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Read more:
<a href="https://theconversation.com/swarming-locusts-people-used-to-eat-them-but-shouldnt-anymore-135058">Swarming locusts: people used to eat them, but shouldn't anymore</a>
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<img src="https://counter.theconversation.com/content/140625/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Leisa Armstrong does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A swarm of roughly 40 million desert locusts can eat the same amount of food in one day as about 35,000 people.Leisa Armstrong, Senior Lecturer in Computer Science, Edith Cowan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1367932020-05-05T15:59:39Z2020-05-05T15:59:39ZGrowing your own food during the coronavirus pandemic? Plan for pests!<figure><img src="https://images.theconversation.com/files/332533/original/file-20200504-83721-1mwshzt.jpg?ixlib=rb-1.1.0&rect=76%2C62%2C3121%2C2353&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Are raccoons ravaging your radishes? Container gardens might be a good option for saving your plants. </span> <span class="attribution"><span class="source">(AP Photo/dpa, Patrick Pleul)</span></span></figcaption></figure><p>Many people are <a href="https://www.cbc.ca/radio/thecurrent/the-current-for-march-30-2020-1.5514566/this-author-says-growing-your-own-victory-garden-could-help-to-ease-the-anxiety-of-the-covid-19-pandemic-1.5515049">trying to grow their own food</a> during the ongoing coronavirus pandemic. Hands are sketching plans onto paper. Window boxes are appearing on balconies. Seeds are sprouting in repurposed plastic containers. </p>
<p>For some of us, this is a familiar ritual. For others, the practice of growing food is brand new territory.</p>
<p>Regardless of experience, most home gardeners will contend with the challenge of pests. The word pest describes any organism that causes harm to humans or human interests. Pests can cause sudden and significant damage to homegrown food. </p>
<p>However, with a little planning, monitoring and intervention, there are steps you can take to reduce the likelihood and severity of these losses. Here are some thoughts to consider:</p>
<h2>Hedge your bets</h2>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/332530/original/file-20200504-83775-1lrboqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/332530/original/file-20200504-83775-1lrboqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/332530/original/file-20200504-83775-1lrboqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/332530/original/file-20200504-83775-1lrboqe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/332530/original/file-20200504-83775-1lrboqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/332530/original/file-20200504-83775-1lrboqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/332530/original/file-20200504-83775-1lrboqe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Mating adult Colorado potato beetles.</span>
<span class="attribution"><span class="source">(Jose Luis Cernadas Iglesias/flickr)</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Pest impact varies considerably over short distances (e.g. sunny front yard to shady backyard). Some pests are picky eaters and only feed on a handful of plant types. For example, the Colorado potato beetle feeds on nightshades, including tomatoes, eggplants, peppers and potatoes. </p>
<p>Other pests pose risk only at certain times of the year. For instance, slug damage to plant seedlings is most severe in early summer. </p>
<p>By planting a diversity of plant species, in different places, with staggered planting dates, you can increase your chances of an abundant harvest. Check the back of your seed package for an estimate of how many days it will take the plant to reach maturity to ensure late-starters will have time to reach their full potential. </p>
<h2>Notice the animals around you and plan ahead</h2>
<p>Think about what animals you regularly see in your neighbourhood — and plan your lines of defence. </p>
<p>Deer have a particular fondness for crops like beans, peas, spinach and sweetcorn. If deer can access your plants, you should consider investing in <a href="https://www.thespruce.com/what-types-of-deer-fencing-are-available-2132105">fencing or netting</a>. Deer tend to turn up their noses at strongly scented plants like mint, onions or oregano, and these can be planted in the places accessible to deer.</p>
<p>If your neighbourhood has a healthy raccoon population, container gardens might be a good option for you. By <a href="https://extension.umd.edu/hgic/topics/container-gardening">planting in containers</a>, you can move your garden indoors at night and protect your harvest. </p>
<p>Are you losing your tomatoes? Try harvesting them before the fruits reach peak ripeness. Placing unripe tomatoes in a paper bag for a few days will allow them to ripen in safety.</p>
<h2>Not all insects are bad</h2>
<p>Many major agricultural pests are insects and cause major losses of food across the world. However, an insect on your plant does not mean that it is causing harm. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-we-should-learn-to-love-all-insects-not-just-the-ones-that-work-for-us-49925">Why we should learn to love all insects – not just the ones that work for us</a>
</strong>
</em>
</p>
<hr>
<p>Try watching the insect for a moment. How does it behave? Does it seem to be eating or laying eggs? If so, you might have a pest. Otherwise it could be a predator searching for a smaller insect to eat, a pollinator warming itself in the sun or simply a passerby on its way elsewhere.</p>
<p>If you have access to a digital camera, try taking a clear photo of the mystery insect. You can upload this photo onto the <a href="https://www.inaturalist.org/">iNaturalist platform</a> along with the time and location of the observation. Interested members of the public, scientists and even a nifty algorithm can help you identify the creatures you encounter.</p>
<h2>Be careful if you use pesticides</h2>
<p>When pest impact is severe, some opt to use pesticides. Active pesticide ingredients (even if labelled as natural or organic) can be harmful if used improperly — <a href="https://www.canada.ca/en/health-canada/services/about-pesticides/using-pesticides-your-lawn.html">always follow the label directions</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/332529/original/file-20200504-83730-wn460e.jpg?ixlib=rb-1.1.0&rect=423%2C239%2C3290%2C2633&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/332529/original/file-20200504-83730-wn460e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=464&fit=crop&dpr=1 600w, https://images.theconversation.com/files/332529/original/file-20200504-83730-wn460e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=464&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/332529/original/file-20200504-83730-wn460e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=464&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/332529/original/file-20200504-83730-wn460e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=583&fit=crop&dpr=1 754w, https://images.theconversation.com/files/332529/original/file-20200504-83730-wn460e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=583&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/332529/original/file-20200504-83730-wn460e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=583&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Sylvain Thibault picks up some gardening supplies at a garden centre in Laval, Que. Some provincial governments have allowed garden centres to re-open during the COVID-19 pandemic.</span>
<span class="attribution"><span class="source">THE CANADIAN PRESS/Ryan Remiorz</span></span>
</figcaption>
</figure>
<p>Pesticide labels are legal documents that must be followed. They are written to protect the health of you, your family, your pets and the wider environment. Some regions <a href="https://www.ontario.ca/page/pesticides-home-lawns-and-gardens">prohibit the use of certain types of pesticides</a>, so please familiarize yourself with local regulations before use.</p>
<p>Preventing hospital visits is even more important given the pressure our health-care system faces under COVID-19. Before using pesticides, try lower-risk options like <a href="https://blog.extension.uconn.edu/2014/04/28/sustainable-pest-control-in-home-gardens/">integrated pest management practices</a>, such as growing pest-resistant plant varieties, using <a href="https://wimastergardener.org/article/floating-row-cover/">row covers</a> or including plant species that are highly attractive to natural enemies (<a href="https://www.youtube.com/watch?v=StSO7LSzzAw">like parasitic wasps</a>) within the garden.</p>
<h2>Ask for help</h2>
<p>Whether you are a new or seasoned home gardener, pest problems can be real head-scratchers. Social media is an excellent way to connect with other gardeners to ask questions. Try <a href="https://www.instagram.com/explore/tags/growyourown/">#growyourown</a> on Instagram, <a href="https://www.reddit.com/r/vegetablegardening">vegetable gardening forums on reddit</a> or <a href="https://www.facebook.com/groups/growyourownveggies/">gardening groups</a> on Facebook.</p>
<p>There are also a number of <a href="https://savvygardening.com/">excellent blogs</a> if you prefer to start with background reading. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ugly-veg-supermarkets-arent-the-biggest-food-wasters-you-are-111398">Ugly veg: supermarkets aren't the biggest food wasters – you are</a>
</strong>
</em>
</p>
<hr>
<p>While we are still physically distanced from one another, try picking up the phone and calling a friend who likes to garden. Take this time to connect with others over the challenges and joys of growing food.</p>
<h2>Be kind to yourself</h2>
<p>The food you purchase at farmer’s market and from grocery stores is grown by experts with knowledge, technology and dedicated time. Due to market demand, more often than not, the food on display is <a href="https://theconversation.com/ugly-veg-supermarkets-arent-the-biggest-food-wasters-you-are-111398">the best of the best</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/332546/original/file-20200504-83740-fqhw1g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/332546/original/file-20200504-83740-fqhw1g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/332546/original/file-20200504-83740-fqhw1g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/332546/original/file-20200504-83740-fqhw1g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/332546/original/file-20200504-83740-fqhw1g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/332546/original/file-20200504-83740-fqhw1g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/332546/original/file-20200504-83740-fqhw1g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">These carrots may look a little strange, but they taste just as good.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>So-called ugly produce is processed, used to feed livestock or wasted. Some of the food you grow will be ugly, often because of pest activity. </p>
<p>You may find caterpillars inside ears of corn or holes in your kale. Instead of fretting, use your discretion. Try removing the damaged portion using a sharp clean knife. </p>
<p>Enjoy the rest. It will be delicious, or at the very least — homegrown.</p><img src="https://counter.theconversation.com/content/136793/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Paul Manning does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Pests can cause sudden and significant damage to homegrown food, but a little planning and intervention can help you cut your losses.Paul Manning, Postdoctoral Research Fellow, Faculty of Agriculture, Dalhousie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1321952020-03-13T01:20:39Z2020-03-13T01:20:39ZAir-dropping poisoned meat to kill bush predators hasn’t worked in the past, and it’s unlikely to help now<figure><img src="https://images.theconversation.com/files/319029/original/file-20200306-118913-vu6qnl.jpg?ixlib=rb-1.1.0&rect=31%2C47%2C3504%2C2152&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>After the summer’s devastating bushfires, the New South Wales government announced a plan to airdrop <a href="https://www.environment.nsw.gov.au/-/media/OEH/Corporate-Site/Documents/Parks-reserves-and-protected-areas/Fire/wildlife-and-conservation-bushfire-recovery-immediate-response-january-2020-200027.pdf">one million poisoned baits</a> in the state’s most vulnerable regions over the next year. The plan is aimed at protecting surviving native animals from foxes, feral cats and wild dogs. </p>
<p>This isn’t the first time aerial baiting has been used in NSW recently. As the fire season got underway in September last year, the government’s biannual aerial baiting program scattered baits over nearly 8 million hectares in the <a href="https://us8.campaign-archive.com/?u=6c8aab7847cab6de73ba979b9&id=5a4baab2ab#mctoc3">Western Division</a> alone - dispensing 43,442 aerial baits and 115,162 ground-laid baits over the drought-stricken region. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/320163/original/file-20200312-111227-18zog2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/320163/original/file-20200312-111227-18zog2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/320163/original/file-20200312-111227-18zog2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/320163/original/file-20200312-111227-18zog2p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/320163/original/file-20200312-111227-18zog2p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/320163/original/file-20200312-111227-18zog2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/320163/original/file-20200312-111227-18zog2p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/320163/original/file-20200312-111227-18zog2p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Biosecurity officers drying meat baits for the Autumn baiting program in Broken Hill last year.</span>
<span class="attribution"><span class="source">NSW Government, Local Land Services, Western Region</span></span>
</figcaption>
</figure>
<p>In a <a href="https://publications.rzsnsw.org.au/doi/10.7882/AZ.2020.011">study published this week</a>, I explore Australia’s history as pioneers of this technology. The review raises serious concerns about the ethics and poor results of baiting programs, and the high uptake of baits by non-target species such as marsupials.</p>
<h2>D-day for dingoes</h2>
<p>Aerial baiting has been Australia’s foremost weapon against pest species for the past 74 years. The initial target was the dingo, to protect unguarded livestock from being killed. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-australia-made-poisoning-animals-normal-107004">How Australia made poisoning animals normal</a>
</strong>
</em>
</p>
<hr>
<p>It started on <a href="https://trove.nla.gov.au/newspaper/article/71430006">Remembrance Day in 1946</a>. Around 367,000 dry meat baits were airdropped across Queensland, each containing enough strychnine to kill an adult dingo. The campaign was considered a victory, despite only recovering one dingo carcass during the initial operation. Livestock predation apparently decreased; tracks in the sand vanished. </p>
<p>The following year, 1.5 million baits were distributed. Then in 1948 the quantity increased to 2.5 million baits across remote regions of Queensland and the Northern Territory. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/320042/original/file-20200312-14977-1iy56x9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/320042/original/file-20200312-14977-1iy56x9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/320042/original/file-20200312-14977-1iy56x9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=476&fit=crop&dpr=1 600w, https://images.theconversation.com/files/320042/original/file-20200312-14977-1iy56x9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=476&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/320042/original/file-20200312-14977-1iy56x9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=476&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/320042/original/file-20200312-14977-1iy56x9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=598&fit=crop&dpr=1 754w, https://images.theconversation.com/files/320042/original/file-20200312-14977-1iy56x9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=598&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/320042/original/file-20200312-14977-1iy56x9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=598&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Livestock predation decreased after airdropping baits, but at what cost?</span>
<span class="attribution"><span class="source">CSIRO Science Image</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Thousands of baits to kill one dingo</h2>
<p>The strychnine tablets took up to <a href="https://publications.csiro.au/rpr/download?pid=procite:f3df657c-27e8-4ac7-844f-4db66563b9a3&dsid=DS1">12 tortuous hours</a> for the poison to deliver its lethal kill. The baits used in research trials were still toxic after 14 weeks. </p>
<p>There was huge public criticism of the project at the time - much of it from graziers. They claimed ants and valuable pest-eating birds – magpies, small hawks, butcher birds, crows, ibis and curlew – were eating the baits. </p>
<p>In response, the Queensland government set up the first monitored trials. The 1954 report from the <a href="https://researchlibrary.agric.wa.gov.au/cgi/viewcontent.cgi?article=1369&context=journal_agriculture3">Chief Vermin Control Officer</a> recorded:</p>
<blockquote>
<p>In the dry season campaigns, the baits are dropped on water-holes, soaks, junctions of dried water courses, gorges in hills and all places where dogs must travel or gather in their search for water and game and in their movements with pups from the breeding areas.</p>
</blockquote>
<p>The data recorded an average 14,941 baits dispensed for every dingo carcass recovered. Anecdotal evidence suggests the program was considered a success.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/316806/original/file-20200224-24685-1jokrqc.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/316806/original/file-20200224-24685-1jokrqc.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=605&fit=crop&dpr=1 600w, https://images.theconversation.com/files/316806/original/file-20200224-24685-1jokrqc.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=605&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/316806/original/file-20200224-24685-1jokrqc.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=605&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/316806/original/file-20200224-24685-1jokrqc.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=761&fit=crop&dpr=1 754w, https://images.theconversation.com/files/316806/original/file-20200224-24685-1jokrqc.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=761&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/316806/original/file-20200224-24685-1jokrqc.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=761&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">CSIRO research worker with young dingo, 1970.</span>
<span class="attribution"><span class="source">National Archives of Australia</span></span>
</figcaption>
</figure>
<p>Then in 1968 – 21 years after aerial campaigns began – a <a href="https://publications.csiro.au/rpr/download?pid=procite:f3df657c-27e8-4ac7-844f-4db66563b9a3&dsid=DS1">four-year CSIRO study</a> tested the effectiveness of aerial baiting. It found the 1954 report was far from conclusive – the dingoes may just have moved elsewhere. And it concluded: “clearly aerial baiting was not effective”. </p>
<p>But there was an important caveat:</p>
<blockquote>
<p>It is important to emphasise that, though this aerial baiting campaign was a failure, such a conclusion does not necessarily apply to any other campaign. </p>
</blockquote>
<p>On the strength of that, aerial baiting programs continued. </p>
<h2>Not much has changed</h2>
<p>Despite millions of baits applied annually to the environment since the 1940s, Australia’s biodiversity has plummeted. </p>
<p>What’s more, developments in the technology haven’t come far. Raw meat baits eventually replaced dry baits in some areas. Strychnine was superseded by 1080, a less harmful poison to non-target native species, and less persistent in the environment. </p>
<p>Trials in the <a href="https://www.publish.csiro.au/wr/wr9860165">1980s</a> brought the bait-to-kill rate down to 750 to 1 (baits per dingo carcass recovered). This was considered a cost-effective and successful outcome. </p>
<p>Soon after, aerial baiting found a new market, becoming the frontline defence against Australia’s plummeting biodiversity from invasive predators. </p>
<h2>Baits are not benign to marsupials</h2>
<p>In 2008, the <a href="https://apvma.gov.au/sites/default/files/publication/15061-sodium-fluororacetate-1080-final-review-report.pdf">Australian Pesticides and Veterinary Medicines Authority</a> imposed a limit of ten baits per kilometre to reduce risk to non-target species.</p>
<p><a href="https://www.pestsmart.org.au/wp-content/uploads/2015/04/FlemingBallard_AerialBaitingRept_APVMA.pdf">Pest control agencies</a> need four times that amount of poison to achieve a successful kill rate. Yet planes have been dispensing baits at this lower and ineffective rate since 2008. </p>
<p>Why? It seems a balance between wildlife safety and effective canine or predator eradication isn’t possible with this technology. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/dingoes-found-in-new-south-wales-but-were-killing-them-as-wild-dogs-126184">Dingoes found in New South Wales, but we're killing them as 'wild dogs'</a>
</strong>
</em>
</p>
<hr>
<p>In fact, it has been impossible to accurately trace the fate of baits thrown from aeroplanes into remote terrain. Even ground baiting trials have proved difficult to monitor. <a href="https://www.publish.csiro.au/wr/WR17182">A 2018 trial</a> found non-target species consumed more than 71% of ground-laid meat baits, including ravens, crows, goannas, monitor lizards, marsupials and ants. </p>
<p>Four young dingoes died during this trial, representing only a 1.25% uptake by target. Despite monitoring with cameras and sand traps, 599 baits out of 961 in the trial disappeared without a trace.</p>
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<p>These baits are not benign. <a href="https://publications.rzsnsw.org.au/doi/10.7882/AZ.2020.011">Repeat doses</a> can kill marsupials; non-lethal doses can kill pouch young. Secondary poisoning can also be lethal. Applying this outdated technology to vulnerable bushfire regions is from a historical viewpoint, potentially hazardous.</p>
<h2>Surely there’s another way</h2>
<p>There are new technologies available to help protect and repair Australia’s <a href="https://conservationbytes.com/2019/10/10/victoria-please-dont-aerial-bait-dingoes/">fragile and broken ecosystems</a>. Remote surveillance, <a href="https://theconversation.com/drones-help-track-wildfires-count-wildlife-and-map-plants-125115">drones</a>, <a href="https://www.nature.com/articles/d42473-019-00304-3">AI</a>, heat sensing equipment, and more could locate populations and dispatch dangerous animals. </p>
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<p>If aerial baiting continues, aerial surveillance could at least follow the fate of the one million baits and tell us what and who is eating them – who lives and who dies in the stripped-bare landscape. </p>
<p>One thing is for certain: halting the program would prevent hundreds of thousands of these poisoned meat baits ending up in the stomachs of our treasured native animals.</p><img src="https://counter.theconversation.com/content/132195/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Justine M. Philip received funding from the University of New England, NSW, towards the research as part of her PhD thesis. The report was written while on a research fellowship with the Center for the History of Global Development, Shanghai University, China. </span></em></p>Aerial baiting has been Australia’s foremost weapon against pest species for the past 74 years. But at what cost?Justine M. Philip, Doctor of Philosophy, Ecosystem Management, Museums Victoria Research InstituteLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1325352020-03-02T10:29:15Z2020-03-02T10:29:15ZWeaving insect wildlife back into the tapestry of life<figure><img src="https://images.theconversation.com/files/317581/original/file-20200227-24651-1fjthbi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">GettyImages</span></span></figcaption></figure><p>Insects are fundamental to the functioning of land and freshwater ecosystems. They permeate all aspects of these ecosystems, chewing and pooing, pollinating, seed spreading and affecting each other’s population levels through predation and parasitism. They also provide ecological processes of vital importance for frogs, lizards, birds and mammals, especially as food items for these vertebrates. </p>
<p>Insects also supply ecosystem services of great benefit in support of human activity, especially food and fibre production, through actions such as pollination, nutrient cycling and control of pest insects. This means that the fate of insects is entwined with that of people and of many other vertebrates. </p>
<p>Yet all is not well with this entomological fabric. Insects <a href="https://www.cabi.org/bookshop/book/9781789241686/">are declining</a> in abundance in many parts of the world, and species are being lost at a rapid rate, especially through the felling of tropical trees. </p>
<p>Scientists <a href="https://www.sciencedirect.com/science/article/pii/S0006320719317823">warn</a> that these declines and losses are undermining the ecosystems on which many lives depend. One of the known root causes is habitat loss. This occurs especially through insect population decline and extinctions arising from the carving up of the landscape and planting extensive fields of single crops which causes landscape degradation and eventually leads to loss of their natural habitat. </p>
<p>Other factors are the uncontrolled use of polluting compounds, especially nitrogen-based fertilisers, overuse of pesticides, the spread of invasive alien species and loss because other species on which they depend are also being lost. </p>
<p>Overarching all of these impacts is <a href="https://theconversation.com/climate-change-is-killing-off-earths-little-creatures-109719">global climate change</a>, which is complex in its manifestation on insect populations and interacts with the other impacts. Climate change is associated with more extreme weather events and with more intense and frequent fires reducing insect populations. It also changes pest prevalence, making their control more difficult. </p>
<p>In addition to this, landscape fragmentation and habitat loss mean that insects cannot move so easily across the terrain to find the conditions that suit them best, as they once did. And these optimal habitats are becoming further apart and smaller. Yet the future is not at all hopeless. <a href="https://www.cabi.org/bookshop/book/9781789241686/">Strategies</a> are being put in place in various parts of the world that when scaled up, will benefit insects globally. </p>
<h2>Unequal effect</h2>
<p>Not all insects are being affected equally. Individual species responses depend on genetic disposition, crafted by past events, often long before human impact on the landscape. </p>
<p>Some species survive well in human-modified circumstances, whether agro-forestry or in cities. Others have the capability of surviving well in certain agro-ecosystems or even city parks. But many are specialists that require particular circumstances or particular host species in order to live. </p>
<p>These specialists are the ones being lost at an alarming rate, especially in tropical forests undergoing rampant deforestation. Their home space is being greatly reduced, lessening their opportunity for survival. When this shrinking space reaches a critically low level, they have nowhere else to go. </p>
<p>In contrast, some genetic modifications enable certain insects to adapt to the changing human environment. The Small ermine moth (<em>Yponomeuta cagnagella</em>), for example, is becoming less <a href="https://royalsocietypublishing.org/doi/full/10.1098/rsbl.2016.0111">responsive</a> to artificial light, improving its chances of survival in the urban environment. </p>
<p>Others can benefit enormously from some artificial environments. This is best seen in the case of artificial ponds. Our <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/fwb.13360">research</a> found that these provide many more opportunities for survival, as more options are available, especially when natural ponds are under drought stress. </p>
<h2>What needs to be done</h2>
<p>International scientists have <a href="https://www.nature.com/articles/s41559-019-1079-8">proposed</a> a roadmap to deal with many of the problems that insects are facing. These are strategies for a way forward not only for long-term insect survival but for ensuring that insect populations continue to provide ecosystem services beneficial to humans. These include the pollination of crops, control of pests using natural predatory and parasitic insects and maintenance of healthy soil. </p>
<p>Recently though, much more detailed strategies have <a href="https://www.cabi.org/bookshop/book/9781789241686/">emerged</a>. These focus on specific ecosystems, whether forest, grassland, freshwater, caves or cities. In short, various research activities around the world, in concert with effective implementation, have illustrated that there are positive ways forward. </p>
<p>These strategies involve much more investment in the future, rather than on destructive short-term economic gains. Different parts of the world can benefit from these findings and tailor them to local conditions. </p>
<p>Among the strategies available are implementation of functional corridor networks of natural vegetation among crops and plantations that enable insects to move across the landscape. Planting particular vegetation between crop rows and around field margins can also be beneficial, as can the careful planting of roadsides. </p>
<p>Rivers can be rehabilitated by ensuring no run-off of pollutants and pesticides, and restoring the river banks with natural vegetation. Reduced insecticide input is essential, as pollinating bees in particular are suffering greatly.</p>
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<a href="https://theconversation.com/honey-bees-already-at-risk-face-a-new-threat-from-a-common-herbicide-106624">Honey bees, already at risk, face a new threat from a common herbicide</a>
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<p>Biological alternatives to pest control, such as parasitic wasps and predatory beetles, are <a href="https://www.wiley.com/en-us/Biodiversity+and+Insect+Pests%3A+Key+Issues+for+Sustainable+Management-p-9780470656860">available</a>. These often go hand in hand with re-establishment of natural vegetation. </p>
<p>Cities, towns and abandoned land can also make a great contribution by increasing the amount of green space relative to the hard grey of the man-made structures. Vegetated green roofs and walls can also help create habitats for insects. </p>
<p>If this generation doesn’t put these strategies in place, the future for future generations will be bleak because options for resilient landscapes are diminishing.</p><img src="https://counter.theconversation.com/content/132535/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Samways receives funding from National Research Foundation, EU projects, Mondi Group. </span></em></p>Insects are essential to the functioning of land and freshwater ecosystems but species populations are being lost at a rapid rate globally.Michael Samways, Professor, Conservation Ecology & Entomology, Stellenbosch UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1308222020-02-02T09:54:00Z2020-02-02T09:54:00ZWe found a way to trap stable flies: their dung preferences helped us<figure><img src="https://images.theconversation.com/files/312783/original/file-20200130-41476-sr4ljj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Female stable flies make careful choices about where to lay their eggs.</span> <span class="attribution"><span class="source">Cosmin Manci/Shutterstock</span></span></figcaption></figure><p>Stable flies (<em>Stomoxys calcitrans</em>) are cold-blooded pests. They feed on the blood of their hosts, which include cattle, camels, horses, dogs and humans. During their feeding they can mechanically transmit viruses and bacteria that cause diseases like <a href="https://academic.oup.com/jme/article/48/3/656/884252">West Nile fever</a>, <a href="https://doi.org/10.2987/10-6070.1">Rift Valley fever</a> and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC260614/">anthrax</a>.</p>
<p>They are found in <a href="https://www.cabi.org/isc/datasheet/63296">most countries</a> around the world, and are particularly common where their livestock hosts are farmed. That’s because they breed on animal dung.</p>
<p>It’s in the breeding process that something surprising emerges about these insects. Our new research shows that female stable flies carefully choose where they lay their eggs to ensure their offspring have the best start in life. It seems the phrase “mother knows best” is true even for flies.</p>
<p>I worked with my PhD student, <a href="https://www.researchgate.net/profile/Bernard_Steve_Baleba">Steve Baleba</a>, and colleagues from the International Centre of Insect Physiology and Ecology (<a href="http://www.icipe.org/">icipe</a>) in Kenya to find out which types of dung female stable flies preferred for laying their eggs. Knowing this – and the information they use to select it – meant we could explore ways to manage their populations. </p>
<p>We found that the flies favoured donkey and sheep dung, so we added the chemicals characteristic of these dung types to traps designed to catch stable flies. This led to a <a href="https://www.nature.com/articles/s41598-019-40479-9">400% increase in the number of flies trapped</a>. More importantly, the traps caught more female stable flies, large numbers of which were ready to lay eggs and contribute to the next generation. This is a valuable way to reduce fly numbers, protect animals and humans, and control the spread of dangerous diseases.</p>
<h2>Pick and choose</h2>
<p>We ran a series of experiments to identify preferred dung types for egg-laying by females and to find out why they were chosen and how flies identified the best dung to use.</p>
<p>Stable flies <a href="https://www.nature.com/articles/s41598-019-40479-9">preferred to lay their eggs on donkey and sheep dung</a> rather than the dung of buffalo, camels, elephants, giraffes or zebra – or controls of grass or moist sand. </p>
<p>And their decision had consequences. The larvae that hatched from eggs laid in donkey and sheep dung developed faster and were larger at the end of the larval stage. This meant that the adults were <a href="https://parasitesandvectors.biomedcentral.com/articles/10.1186/s13071-019-3483-y">heavier and had larger wings</a> than their peers, which may improve their flight performance. </p>
<p>The improved performance of offspring developing in donkey and sheep dung was closely correlated with higher elemental nitrogen, potassium and zinc content in the dung. In contrast, camel and cow dung – which the flies did not choose – had relatively low concentrations of these elements, and had higher carbon, calcium and water content.</p>
<p>Females also preferred to lay their eggs in dung that was <a href="https://www.frontiersin.org/articles/10.3389/fevo.2020.00005/full">free of competitors and parasites</a>. If dung already contained stable fly larvae – even as few as ten – females laid fewer eggs than on dung with no larvae. Similarly, if dung was already being used by housefly (<em>Musca domestica</em>) larvae, stable flies laid fewer eggs, although this effect was only seen when at least 20 housefly larvae were present. When presented with dung containing parasitic mites (<em>Macrocheles muscaedomesticae</em>), female stable flies also avoided laying eggs. </p>
<p>All these choices benefited the flies’ offspring. They were larger, and more of them survived to reach adulthood if they developed without competition. In the absence of parasitic mites, more eggs hatched, more larvae survived to the pupal stage, and adults survived for longer.</p>
<h2>Common sense</h2>
<p>Stable flies decide where to lay their eggs using sight and smell. Vision is important for avoiding dung containing parasitic mites. We know this because the same number of egg clutches were laid on dung with and without mites when we tested egg-laying in the dark. This surprised us because at least one other fly species (<em>Drosophila hydei</em>) seems to avoid mite infection using their senses of <a href="https://www.journals.uchicago.edu/doi/abs/10.1086/691704">smell and touch</a>.</p>
<p>Either taste or smell is involved with avoiding competition because even in the dark, females laid fewer clutches on dung with competitors. To select between different dung types, female stable flies use their sense of smell. We found that two chemicals characteristic of donkey and sheep dung (β-citronellene and carvone, respectively) encouraged stable flies to lay their eggs on moist sand that had been treated with these chemicals.</p>
<p>We believe that the decision by female stable flies to lay eggs on a preferred dung type is probably hard-wired into their sensory and nervous systems. This is because we found <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/een.12748">no evidence for females learning</a> to prefer one dung type over another based on the dung they themselves developed in. That said, larvae that accidentally wander away from a preferred dung type have a short-term memory that helps them to return to it.</p>
<p>These results all show that stable flies evolved to find the best conditions for the survival of their offspring. </p>
<p>Armed with this information we were able to test traps using the chemicals β-citronellene and carvone. As I’ve said, this was hugely successful. The next step is to optimise the blend of these chemicals and commercialise it. We also want to find out which chemicals stable flies use to avoid competition. These could be developed into repellents to protect humans and livestock from stable flies and the diseases they transmit.</p><img src="https://counter.theconversation.com/content/130822/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christopher Weldon does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Savvy female stable flies prefer to lay their eggs on donkey and sheep dung. Knowing where they choose to do this will help us manage disease.Christopher Weldon, Associate Professor in Entomology, University of PretoriaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1298342020-01-17T09:37:46Z2020-01-17T09:37:46ZLessons on how to effectively tackle insect invasions<figure><img src="https://images.theconversation.com/files/309960/original/file-20200114-151867-1bup8wt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Flying desert locust</span> <span class="attribution"><span class="source">Holger Kirk/Shutterstock</span></span></figcaption></figure><p>Kenyan food production and grazing land is under threat from a huge <a href="https://af.reuters.com/article/topNews/idAFKBN1Z917K-OZATP">desert locust invasion</a>. The insects are currently in two counties in northern Kenya and are <a href="http://www.fao.org/ag/locusts/en/info/info/index.html">now spreading</a> to other Kenyan regions including Meru, Laikipia, and Rift Valley. The government has yet to quantify losses but past attacks <a href="https://www.nation.co.ke/news/Desert-locusts-threaten-food-security-and-economy-/1056-5416940-4ms2ajz/index.html">have caused</a> harvest losses of up to 70%.</p>
<p>Desert locusts are considered to be the <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/desert-locust">most dangerous</a> of all migratory pests because they can eventually develop wings and form a cohesive swarm which can cross continents and seas. They have the ability to devour crops from entire farm fields in a single morning. Studies show that <a href="https://science.sciencemag.org/content/323/5914/627">large swarms</a> form because of factors including changes to the environment, <a href="https://science.sciencemag.org/content/323/5914/627">population structure</a> and <a href="https://www.cambridge.org/core/journals/biological-reviews/article/behavioural-analysis-of-phase-change-in-the-desert-locust/37B6831FD6A337D1F07BB115B20356E8">behaviour</a>.</p>
<p>These desert locusts <a href="http://www.fao.org/resilience/news-events/detail/en/c/1236477/">migrated from</a> Yemen – a traditional breeding area – through Djibouti, Somalia and Ethiopia. The region has had more rainfall than usual which can could have led to this situation. After periods of drought, when vegetation flushes occur in major desert locust breeding areas, rapid population build ups and competition for food can lead to a swarm developing.</p>
<p>To fight these voracious pests, the government of Kenya <a href="https://www.nation.co.ke/counties/Locust-invasion-Aerial-spraying-begins-Isiolo-Meru/1107872-5416730-smj7i6/index.html">is using</a> chemical pesticides, often the usual immediate response of African governments to these outbreaks. This was the approach used to curb the spread of the invasive fall armyworm in Kenya, <a href="https://www.voanews.com/africa/fall-armyworms-hit-malawi-president-appeals-help">Malawi</a> and Ghana, for instance. But they don’t work in the long run.</p>
<p>Pesticides are chemicals used to kill pests – from animal pests to weeds. Their use is growing in many countries in general, including <a href="https://www.tandfonline.com/doi/full/10.1080/19315260.2013.800625?scroll=top&needAccess=true&">Cameroon</a>, <a href="https://academic.oup.com/annweh/article-abstract/60/5/551/2196140?redirectedFrom=fulltext">Ethiopia</a>, <a href="http://onlinelibrary.wiley.com/doi/10.1002/ps.1178/abstract">Ghana</a>, <a href="http://www.worldagroforestry.org/publication/potential-environmental-impacts-pesticide-use-vegetable-sub-sector-kenya">Kenya</a> and <a href="http://irepos.unijos.edu.ng/jspui/bitstream/123456789/1870/1/91393-170650-1-SM.pdf">Nigeria</a>. In 2017, Nigeria alone spent over <a href="http://securitymonitorng.com/2017/10/07/nigerian-peasant-farmers-spend-400-million-annually-on-purchase-of-pesticide/">US$400 million</a> on these chemicals.</p>
<p>While there are <a href="https://croplife.org/case-study/importance-of-pesticides-for-growing-wheat-in-sub-saharan-africa/">benefits</a> of using pesticides – including <a href="http://science.sciencemag.org/content/341/6147/730/tab-pdf">directly</a> reducing the incidence of the invading pests – the benefits <a href="https://link.springer.com/article/10.1007/s13593-012-0105-x">are</a> short-term: insects can quickly become resistant to them. </p>
<p>Pesticides are also bad for the <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/fes3.108">environment</a> and the <a href="https://www.sciencedirect.com/science/article/pii/S004896971631926X">health</a> of consumers and farmers. Many European countries have <a href="https://library.wur.nl/WebQuery/wurpubs/fulltext/442443">banned</a> some of them for those reasons. In 2017, <a href="http://www.pan-uk.org/site/wp-content/uploads/United-Nations-Report-of-the-Special-Rapporteur-on-the-right-to-food.pdf">a United Nations report</a> showed that <a href="https://www.aljazeera.com/news/2017/03/200000-die-year-pesticide-poisoning-170308140641105.html">about</a> 200,000 people, <a href="https://news.un.org/en/story/2017/03/552872-un-human-rights-experts-call-global-treaty-regulate-dangerous-pesticides">mostly</a> from developing countries, die every year from pesticide poisoning.</p>
<p>Countries must therefore promote alternatives or look more carefully at how to prevent insect invasions in the first place.</p>
<h2>Integrated pest management</h2>
<p>There are alternatives to pesticides including <a href="http://www2.ipm.ucanr.edu/WhatIsIPM/">integrated pest management</a>. This is an <a href="https://www.epa.gov/managing-pests-schools/introduction-integrated-pest-management">approach</a> that doesn’t rule out the use of pesticides, but uses them as little as possible. </p>
<p>Integrated pest management also promotes the use of safer alternatives, like biocontrol, which uses natural enemies to control pests, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3130386/">biopesticides</a> and cultural control practices, which modify the growing environment to reduce unwanted pests. </p>
<p>Biopesticides have been used to manage the <a href="https://blog.invasive-species.org/2019/07/18/deploying-biopesticides-to-combat-fall-armyworm-in-south-sudan/">invasive fall armyworm</a> <a href="https://www.youtube.com/watch?v=zySjdXI1Nc0">control</a> <a href="http://www.fao.org/ag/locusts/common/ecg/1117_en_BiopesticidesE.pdf">locust</a>, but they’re not popular because they <a href="https://www.annualreviews.org/doi/full/10.1146/annurev.ento.46.1.667?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed">take time</a> to kill the pest. </p>
<p>Countries also need to be proactive in dealing with potential invasions – reactive measures aren’t enough. With warming temperatures in many parts of the continent, some insects will grow and mature faster, meaning <a href="https://www.pnas.org/content/113/27/7575">more</a> pest invasions. Sub-Saharan African countries will be greatly <a href="https://www.researchgate.net/publication/333665876_Climate_Change_and_Rapidly_Evolving_Pests_and_Diseases_in_Southern_Africa">affected</a>. Recent examples include the <a href="https://www.invasive-species.org/wp-content/uploads/sites/2/2019/02/FAW-Evidence-Note-October-2018.pdf">fall armyworm invasions</a> that caused billions of dollars in losses on the continent while contributing to food insecurity for millions of farmers. </p>
<p>Governments must work to prevent insect invasions from happening in the first place. </p>
<h2>Preventing invasions</h2>
<p>It’s possible for African countries to anticipate and prepare for invasions. They can tap into existing support tools to identify potential invasive pests. The <a href="https://www.cabi.org/horizonscanningtool">Horizon Scanning Tool</a>, for example, is a tool with which countries can generate a list of insect species that might invade from neighbouring countries – particularly important if they share similar climates or are linked by transport and trade routes. Because countries know about potential invaders ahead of time, they can prepare action plans to be rolled out when predicted invasions happen.</p>
<p>African countries must also strengthen their own pest surveillance efforts. Most African countries <a href="https://www.agrilinks.org/sites/default/files/resources/eba_plant_protection_data_in_action_final_january_2018_0.pdf">don’t</a> have good systems – such as border screening – in place to control the introduction of plants and plant products, which could have pests or diseases. Many governments <a href="https://eba.worldbank.org/en/data/exploretopics/plant">also don’t</a> carry out routine pest surveillance.</p>
<p>Countries should also learn from others that have successfully tackled invasions. For instance, the US <a href="https://www.invasivespeciesinfo.gov/federal-governments-response-invasive-species">has</a> invasive insect species task forces, councils, committees and advisory groups to provide expertise and guidance on how to prepare for and tackle insect invasions when they happen. </p>
<p>As with the fall armyworm, and through meetings organised by the United Nations Food and Agricultural Organisation, African countries were able to <a href="https://www.youtube.com/watch?v=TjrdnEJQlwA">learn</a> from countries like Brazil that have successfully tackled fall armyworm invasion. For instance, they learned how to accurately identify the pests and how to use the right biological control agents. </p>
<p>Finally, countries must have emergency funds at their disposal to support citizens who become food insecure because of the invading insects. In dealing with recent fall armyworm, this was sorely lacking.</p>
<p>By anticipating pest outbreaks and invasions and having multi-pronged and comprehensive efforts laid out, African countries can effectively deal with pest outbreaks and invasions. Key to this is being proactive, rather than reactive.</p><img src="https://counter.theconversation.com/content/129834/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Esther Ndumi Ngumbi does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Countries should promote alternatives to pesticides and more carefully examine how to prevent insect invasions in the first placeEsther Ndumi Ngumbi, Assistant Professor, Department of Entomology; African-American Studies, University of Illinois at Urbana-ChampaignLicensed as Creative Commons – attribution, no derivatives.