tag:theconversation.com,2011:/us/topics/wildlife-monitoring-49773/articlesWildlife monitoring – The Conversation2023-06-22T12:30:35Ztag:theconversation.com,2011:article/2081532023-06-22T12:30:35Z2023-06-22T12:30:35ZTo see how smoke affects endangered orangutans, we studied their voices during and after massive Indonesian wildfires<figure><img src="https://images.theconversation.com/files/533199/original/file-20230621-11493-h6xfhj.jpeg?ixlib=rb-1.1.0&rect=7%2C0%2C4861%2C3080&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An adult male orangutan contemplates his next move in haze produced by Indonesia's 2015 wildfires.</span> <span class="attribution"><span class="source">Wendy Erb</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Bornean orangutans are one of three orangutan species, all <a href="https://www.iucnredlist.org/search?query=orangutan&searchType=species">critically endangered</a>. They thrive in carbon-rich peat swamp forests on the Indonesian island of Borneo. These habitats are also the sites of massive wildfires.</p>
<p>Indonesian wildfires in 2015 caused some of the <a href="https://doi.org/10.3390/rs10040495">worst fire-driven air pollution</a> ever recorded. The fires were driven by an <a href="https://www.noaa.gov/understanding-el-nino#">El Niño climatic cycle</a>, which <a href="https://www.nasa.gov/feature/Goddard/2016/severe-2015-indonesian-fire-season-linked-to-el-nino-drought">caused especially dry weather</a> in the region.</p>
<p>Compared to other wildfires, peatland fires smolder underground and produce exceptionally high levels of hazardous gases and particulate matter – a leading cause of <a href="https://theconversation.com/wildfire-smoke-can-harm-human-health-even-when-the-fire-is-hundreds-of-miles-away-a-toxicologist-explains-why-206057">global pollution-related deaths and illnesses</a>. </p>
<p>Orangutans are well known as an “<a href="https://www.britannica.com/science/indicator-species">indicator species</a>” – one that can serve as a proxy for the health of an ecosystem. Changes in their environments often cause conspicuous changes in the apes’ health and behavior. Frequent and persistent exposure to toxic smoke could have severe consequences for orangutans and other wildlife.</p>
<p>Toxic air pollution also poses serious health and safety risks for researchers. However, <a href="https://doi.org/10.1093/biosci/biy147">remote sensing techniques</a>, such as satellite images, GPS data and acoustic monitoring, are increasingly popular ways to track wildlife populations and see how creatures respond to changes in their environments.</p>
<p>I have studied the behavior, ecology and acoustic communication of <a href="https://scholar.google.com/citations?user=ykHYzwEAAAAJ&hl=en">wild primates in Indonesia</a> since 2005. In a new study, my co-authors and I investigated how wild orangutans in Borneo were affected by toxic emissions from Indonesia’s 2015 peatland wildfires – by <a href="https://doi.org/10.1016/j.isci.2023.107088">studying their voices</a>. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/cBnbLJ5TzvE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Indonesia’s degraded peatlands are tinderboxes that can easily ignite with several weeks of dry weather.</span></figcaption>
</figure>
<h2>Smoke exposure poses long-term risks</h2>
<p>Around the world, <a href="https://www.unep.org/news-and-stories/press-release/number-wildfires-rise-50-2100-and-governments-are-not-prepared">wildfires are on the rise</a>. They often produce a thick blanket of haze that contains diverse hazardous gases and particulate matter, or PM. Most recently, smoke from Canadian wildfires blanketed the U.S. East Coast and Midwest in early June 2023, <a href="https://www.youtube.com/watch?v=kLN3kBthm9Y">turning skies orange</a> and triggering public health alerts.</p>
<p>Studies have shown that <a href="https://doi.org/10.1016/j.envres.2014.10.015">human health risks from wildfire smoke</a> include respiratory and cardiovascular illnesses, systemic inflammation and premature death. Much less is known about how smoke affects wildlife, but in a pair of studies published <a href="https://doi.org/10.1016/j.reprotox.2021.08.005">in 2021</a> <a href="https://doi.org/10.1038/s41467-022-29436-9">and 2022</a>, scientists at the <a href="https://cnprc.ucdavis.edu/">California National Primate Research Center</a> reported alarming findings.</p>
<p>After less than two weeks of exposure to high concentrations of particulate matter – in particular, ultrafine particles measuring less than 2.5 microns in diameter, which are known as PM2.5 – captive <a href="https://www.britannica.com/animal/rhesus-monkey">rhesus macaques</a> suffered a spike in pregnancy loss. What’s more, surviving fetuses and infants suffered long-term effects on lung capacity, immune responses, inflammation, cortisol levels, behavior and memory. </p>
<p>During Indonesia’s 2015 fires, Borneo’s air had particulate matter concentrations nearly an order of magnitude higher than the levels in these studies. This made the potential implications for people and wildlife who gasped through Indonesia’s wildfire smoke for nearly two months extremely worrying.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/533205/original/file-20230621-17-x1066c.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Fire and smoke rise from charred ground near a scorched tree." src="https://images.theconversation.com/files/533205/original/file-20230621-17-x1066c.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/533205/original/file-20230621-17-x1066c.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=379&fit=crop&dpr=1 600w, https://images.theconversation.com/files/533205/original/file-20230621-17-x1066c.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=379&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/533205/original/file-20230621-17-x1066c.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=379&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/533205/original/file-20230621-17-x1066c.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=477&fit=crop&dpr=1 754w, https://images.theconversation.com/files/533205/original/file-20230621-17-x1066c.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=477&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/533205/original/file-20230621-17-x1066c.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=477&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 wildfire blazes in a small rubber tree garden along the border of the Tuanan study area during Indonesia’s 2015 wildfires.</span>
<span class="attribution"><span class="source">Wendy Erb</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Orangutans in the haze</h2>
<p>I was studying wild orangutans in the forests of Indonesian Borneo when the 2015 fires started. My colleagues and I at the <a href="https://coreborneo.com/tuanan-research-station/">Tuanan Orangutan Research Station</a> tracked local fires and patrolled nearby hot spots to assess the risk of fire spreading to our research area. </p>
<p>Wearing N-95 masks, we continued to monitor orangutans in hopes of learning how the animals were coping with encroaching fires and thick smoke. A few weeks into the fire season, I noticed a difference in the sound of the males’ “<a href="https://wildambience.com/wildlife-sounds/orangutan/">long call</a>,” which was the focus of <a href="https://wendyerb.weebly.com/projects.html">my research</a>. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/cRJoooWf5vU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">An adult male Bornean orangutan’s long call.</span></figcaption>
</figure>
<p>Long calls are booming vocalizations that can be heard over distances of more than half a mile (1 kilometer). Orangutans are semi-solitary and live in dispersed communities, so these calls serve an important social role. Adult males make them to advertise their prowess to listening females in the area and to scare off any eavesdropping rival males. A couple of weeks after the smoke had appeared, I thought these males sounded raggedy – a little like humans who smoke a lot. </p>
<p>We observed the orangutans for 44 days during the fires, until large blazes encroached on our study area. At that point, we stopped the study to help extinguish the blazes with local firefighting teams and other government and nonprofit groups. Fires burned in our study area for three weeks.</p>
<p>Using data that we collected before, during and after the fires, I led an analysis of this Bornean orangutan population’s <a href="https://doi.org/10.1016/j.isci.2023.107088">behavior and health</a>. My co-authors and I found that in the weeks after the fires, the apes reduced their activities – resting more and traveling shorter distances – and consumed more calories than normal. </p>
<p>But although they were eating more and moving less, we found by collecting and testing the apes’ urine that they were <a href="https://doi.org/10.1038/s41598-018-25847-1">still burning stored fat</a> – a sign that they somehow were using up more energy. We hypothesized that the cause <a href="https://my.clevelandclinic.org/health/symptoms/21660-inflammation#:%7E:text=The%20most%20common%20reasons%20for,from%20an%20infection%20or%20injury">might be inflammation</a> – the swelling, fever, pain and fatigue that human and animal bodies experience in response to infection or injury. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/533206/original/file-20230621-20-pixdob.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An orangutan reclines in a tree surrounded by haze." src="https://images.theconversation.com/files/533206/original/file-20230621-20-pixdob.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/533206/original/file-20230621-20-pixdob.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=380&fit=crop&dpr=1 600w, https://images.theconversation.com/files/533206/original/file-20230621-20-pixdob.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=380&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/533206/original/file-20230621-20-pixdob.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=380&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/533206/original/file-20230621-20-pixdob.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=477&fit=crop&dpr=1 754w, https://images.theconversation.com/files/533206/original/file-20230621-20-pixdob.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=477&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/533206/original/file-20230621-20-pixdob.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=477&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Otto, one of four adult male orangutans observed and recorded for this research, takes a midday smoky nap during Indonesia’s 2015 wildfires.</span>
<span class="attribution"><span class="source">Wendy Erb</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Sentinel sounds</h2>
<p>Studies have shown that when humans are exposed to particulate matter, they can experience inflammation, both in their <a href="https://doi.org/10.1097/JOM.0000000000001775">respiratory tracts</a> and <a href="https://doi.org/10.1164/ajrccm.164.5.2010160">throughout their bodies</a>. We wanted to know whether inhaling wildfire smoke would cause vocal changes in orangutans, just as inhaling cigarette smoke does in humans.</p>
<p>For this study, my co-authors and I carefully analyzed more than 100 sound recordings of four male orangutans that we followed before and during the fires to measure their vocal responses to wildfire smoke. Research has shown that a suite of vocal features – including <a href="https://www.asha.org/practice-portal/clinical-topics/voice-disorders/#collapse_2">pitch, vocal harshness or hoarseness, and shaky voice</a> – reflects the underlying health and condition of both human and nonhuman animals. We were looking for acoustic clues about how this toxic air might be affecting the orangutans. </p>
<p>During the fires and for several weeks after the smoke cleared, these males called less frequently than usual. Normally, orangutans call about six times a day. But during the fires, their call rate was cut in half. Their voices dropped in pitch, showing more vocal harshness and irregularities. </p>
<p>Collectively, these features of vocal quality have been linked to inflammation, stress and disease – including COVID-19 – in <a href="https://doi.org/10.1016/j.eswa.2017.04.012">human</a> and <a href="https://doi.org/10.1038/s41598-021-83614-1">nonhuman</a> animals.</p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CCoXocEBgiv/?utm_source=ig_web_copy_link\u0026igshid=MzRlODBiNWFlZA==","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<h2>Listening to vocal species</h2>
<p>Increasingly frequent and prolonged exposure to toxic smoke could have severe consequences for orangutans and other animals. Our research highlights the urgent need to understand the long-term and far-ranging effects of peatland fires in Indonesia, which is one of the <a href="https://www.cbd.int/countries/profile/?country=id">most biodiverse countries in the world</a>. </p>
<p>By uncovering the linkages between acoustic, behavioral and energetic shifts in orangutans, our study highlights a way for scientists and wildlife managers to safely monitor the health of orangutans and other animals. Using <a href="https://www.birds.cornell.edu/ccb/passive-acoustic-monitoring/">passive acoustic monitoring</a> to study vocally active indicator species, like orangutans, could unlock critical insights into wildfire smoke’s effects on wildlife populations worldwide.</p><img src="https://counter.theconversation.com/content/208153/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Wendy M. Erb is affiliated with the American Society of Primatologists; the Borneo Nature Foundation; and Primate Conservation, Inc. She has received research funding from the American Association of University Women; the American Institute for Indonesian Studies; the American Association of Biological Anthropologists; the American Society of Primatologists; the British Academy; the Conservation, Food, and Health Foundation; Conservation International; Cornell University; Disney Conservation Fund; the Fulbright Program; the International Society of Primatologists; and the National Science Foundation. </span></em></p>Orangutans are vocal animals, so analyzing their calls during events like wildfires can indicate how smoke is affecting their health.Wendy M. Erb, Postdoctoral Associate in Conservation Bioacoustics, Cornell UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1645292021-09-17T12:19:15Z2021-09-17T12:19:15ZScientists at work: We use environmental DNA to monitor how human activities affect life in rivers and streams<figure><img src="https://images.theconversation.com/files/420917/original/file-20210913-21-185he0a.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3259%2C1832&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Environmental DNA is a promising tool for tracking species in freshwater ecosystems like Oregon's Elkhorn Creek.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/NZgE7n">Greg Shine, BLM/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Rivers, lakes and wetlands cover just 1% of the Earth’s surface but are home to nearly 10% of all species, including fish, mammals, birds, insects and crustaceans. But these rich, <a href="https://wwfcee.org/pdf_collections/7/world_s_forgotten_fishes__final_april9_.pdf">diverse</a> ecosystems are <a href="https://wwf.panda.org/discover/our_focus/freshwater_practice/the_world_s_forgotten_fishes/">in free fall</a>. Worldwide, species are <a href="https://www.un.org/sustainabledevelopment/blog/2019/05/nature-decline-unprecedented-report/">declining faster now</a> than at any other time in human history, and fresh waters are losing more species than land or ocean ecosystems.</p>
<p>Today about <a href="https://www.iucn.org/theme/species/our-work/freshwater-biodiversity">1 in 4 freshwater creatures face extinction</a>. Wetlands are disappearing <a href="https://doi.org/10.1093/biosci/biaa002">three times faster than forests</a>. Across the globe, water quality is plummeting, polluted by <a href="https://uneplive.unep.org/media/docs/assessments/unep_wwqa_report_web.pdf">plastic, sewage, mining sludge, industrial and agricultural chemicals and much more</a>. </p>
<p>It’s challenging to study how these stresses are affecting aquatic life. There are many diverse threats, and river networks cover broad geographic regions. Often they run through remote, nearly inaccessible areas. Current techniques for monitoring freshwater species are <a href="https://doi.org/10.1111/j.1365-2664.2010.01864.x">labor-intensive and costly</a>.</p>
<p>In our <a href="https://esajournals.onlinelibrary.wiley.com/doi/10.1002/eap.2389">work</a> as <a href="https://scholar.google.fr/citations?user=rhmblP8AAAAJ&hl=fr">researchers</a> in <a href="https://scholar.google.com/citations?user=hxHYAA8AAAAJ&hl=en">ecology</a>, we are testing a new method that can vastly expand biomonitoring: using environmental DNA, or eDNA, in rivers to <a href="https://doi.org/10.1016/j.tree.2014.04.003">catalog and count species</a>. Federal and local agencies need this data to restore water quality and save dwindling species from extinction. </p>
<figure>
<iframe src="https://player.vimeo.com/video/66103145" width="500" height="281" frameborder="0" webkitallowfullscreen="" mozallowfullscreen="" allowfullscreen=""></iframe>
<figcaption><span class="caption">This preview of the film “Hidden Rivers” reveals the diverse and little-known life in Southern Appalachian waterways.</span></figcaption>
</figure>
<h2>Traditional methods are slow and expensive</h2>
<p>With traditional biomonitoring methods, scientists count individual species and their abundance at just <a href="https://doi.org/10.1111/j.1365-2664.2010.01864.x">a few sites</a>. For example, one recent study of <a href="https://doi.org/10.1086/676997">mountaintop mining impacts on fish in West Virginia</a> sampled just four sites with a team of four researchers. </p>
<p>Collecting and identifying aquatic organisms requires highly skilled ecologists and taxonomists with expertise in a wide variety of freshwater species. For each sample of fish or invertebrates collected in the field, it takes from hours to weeks to identify all of the species. Only wealthy nations can afford this costly process.</p>
<p>Conserving threatened and endangered species and keeping river ecosystems healthy requires monitoring broad areas over time. Sensitive aquatic insects and fish species are the freshwater equivalent of the proverbial canary in a coal mine: If these species are absent, that’s a strong indicator of water quality problems. The cause may be mining, agriculture, urbanization or other sources, as well as <a href="https://www.nwf.org/Magazines/National-Wildlife/2012/AugSept/Animals/Appalachian-Rivers">dams</a> that block animals’ downstream movements.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/W3lcHdFyzrQ?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Scientists sample for fish in a Maryland stream by ‘electrofishing’ – stunning fish with a mild electrical pulse so they can be collected, identified and released after the shock wears off.</span></figcaption>
</figure>
<h2>Free-floating genetic evidence</h2>
<p>Innovations in genetic technology have created a powerful, affordable new tool that we are now testing. The process involves extracting eDNA from genetic material floating in the water – skin, scales, feces and single-celled organisms, such as bacteria. </p>
<p>By analyzing this genetic information, we can <a href="https://doi.org/10.1111/j.1365-294X.2012.05470.x">detect a wide range of species</a>. We started considering using eDNA for our research in 2018, after several studies demonstrated its power to monitor single species of interest or groups of organisms in <a href="https://doi.org/10.1016/j.tree.2014.04.003">rivers</a> and <a href="https://theconversation.com/fishing-for-dna-free-floating-edna-identifies-presence-and-abundance-of-ocean-life-75957">oceans</a>.</p>
<p>Collecting eDNA is easy: One 4-ounce water sample can capture remnant DNA from thousands of aquatic species. Another benefit is that it doesn’t require killing wildlife for identification.</p>
<p>In the lab, we analyze the DNA from different taxonomic groups one by one: bacteria, algae, fish and <a href="https://www.epa.gov/national-aquatic-resource-surveys/indicators-benthic-macroinvertebrates">macroinvertebrates</a> – organisms that lack backbones and are large enough to see, such as snails, worms and beetles. Many researchers study just one group, but we assess all of them at the same time. </p>
<p>We then match our DNA sequences with freshwater species that are already catalogued in existing databases. In this way, we can chart the distribution and abundance of these organisms within and across rivers.</p>
<p>This process requires just a cheap filter, a syringe and vials, and anyone can do it. Commercial eDNA companies charge less than $200 to extract and sequence a sample. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/421209/original/file-20210914-13-u7g2zq.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Graphic showing how scientists analyze eDNA to detect different species." src="https://images.theconversation.com/files/421209/original/file-20210914-13-u7g2zq.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421209/original/file-20210914-13-u7g2zq.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=364&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421209/original/file-20210914-13-u7g2zq.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=364&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421209/original/file-20210914-13-u7g2zq.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=364&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421209/original/file-20210914-13-u7g2zq.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=457&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421209/original/file-20210914-13-u7g2zq.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=457&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421209/original/file-20210914-13-u7g2zq.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=457&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Most eDNA the authors collect from streams is microbial (the gray DNA in the cartoon above). Without special techniques, they would not ‘see’ the less frequent DNA from other taxonomic groups, so their surveys would generate a species abundance curve like the one on the bottom left, in which most groups of conservation concern are too rare to detect or fall into the ‘long tail’ of rare occurrences. By using targeted primers – short stretches of DNA that are unique to specific groups of organisms – they can amplify the eDNA of less abundant groups, like algae, arthropods and fish, as shown on the right.</span>
<span class="attribution"><span class="source">Emily Bernhardt, produced using Biorender</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Altered rivers</h2>
<p>Using this method, we extensively surveyed 93 rivers in West Virginia – looking at the entire tree of life, from the tiniest bacteria to fish – in two days with a four-person team. </p>
<p>The Appalachian rivers that we study teem with life. These are some of the world’s most biologically diverse temperate freshwater ecosystems, home to <a href="https://www.conservationfisheries.org/appalachia">many fish species</a>, as well as salamanders, crayfish, mussels and aquatic insects. <a href="https://www.natureserve.org/publications/rivers-life-critical-watersheds-protecting-freshwater-biodiversity">Many are found nowhere else</a>. We tallied <a href="https://doi.org/10.1002/eap.2389">more than 10,000 different species</a> in those 93 waterways. </p>
<p>The area where we worked is an intensive coal mining region, which heavily affects waterways. Liquids draining from mines are <a href="https://www.epa.gov/nps/abandoned-mine-drainage">acidic</a>, but in this region they react with limestone rock, so the net effect is to make local streams alkaline. Mine drainage also increases streams’ salinity and concentrations of <a href="https://doi.org/10.1021/es301144q">sulfate and other contaminants</a>. Our research revealed that mined watersheds held 40% fewer species than areas without mining operations, and the organisms we detected were less abundant than in unaffected rivers. </p>
<h2>Assessing river health</h2>
<p>We believe this new approach represents a revolution for biomonitoring, expanding our ability to quantify and study freshwater life. It’s also an important new conservation tool, allowing scientists to track changes in populations of endangered or invasive species. Researchers also can use eDNA to monitor biodiversity or discover new species in oceans or soils. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1303976383178309633"}"></div></p>
<p>This <a href="https://doi.org/10.1002/fee.1490">open-science method</a> makes all DNA data widely available, with nearly all sequences placed in public repositories. Moving forward, we expect that it will aid many types of research, as well as state and local monitoring and conservation programs. Investments in collecting eDNA and identifying organisms and analyzing their genetic signatures will continue to make it a more effective tool.</p>
<p>[<em>Over 100,000 readers rely on The Conversation’s newsletter to understand the world.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=100Ksignup">Sign up today</a>.]</p>
<p>Efforts are underway to better target various individual species, focusing on those that are endangered, invasives that damage ecosystems and sensitive species that serve as indicators of river health. Scientists are freezing eDNA samples at -112 degrees F (-80 C) in expectation that technological advances may yield <a href="https://doi.org/10.1038/s41559-018-0614-3">more information in the future</a>.</p>
<p>Traditional monitoring approaches remain valuable, but eDNA adds an important new tool to the toolkit. Together, these approaches can begin to answer many questions about food webs, the conservation status of species, reproduction rates, species interactions, organisms’ health, disease and more.</p><img src="https://counter.theconversation.com/content/164529/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Marie Simonin is a research scientist at INRAE, the French National Research Institute for Agriculture, Food and Environment.</span></em></p><p class="fine-print"><em><span>Emily S. Bernhardt has received funding to research the impacts of mountaintop removal coal mining from the Foundation for the Carolinas and the National Science Foundation, which supported the work described in this article. She currently is engaged as an expert on these impacts by the US Department of Justice.</span></em></p>Rivers are among the most embattled ecosystems on Earth. Researchers are testing a new, inexpensive way to study river health by using eDNA to count the species that rivers harbor.Marie Simonin, Research Scientist, InraeEmily S. Bernhardt, Professor of Biology, Duke UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1643682021-07-14T12:52:22Z2021-07-14T12:52:22ZRumble in the jungle: an ear to the ground can tell us how elephants are faring in the wild<figure><img src="https://images.theconversation.com/files/411108/original/file-20210713-23-mlrrqx.png?ixlib=rb-1.1.0&rect=0%2C0%2C2830%2C1888&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Rumbles elephants make travel through the air and the ground.</span> <span class="attribution"><span class="source">Beth Mortimer</span>, <span class="license">Author provided</span></span></figcaption></figure><p>African elephants can be found roaming the forests and grasslands of 37 countries across the continent. But sadly, these sentient and intelligent animals are rapidly declining, and were <a href="https://www.iucn.org/news/species/202103/african-elephant-species-now-endangered-and-critically-endangered-iucn-red-list">recently declared endangered</a>. </p>
<p>For these remaining elephants to find each other, they make a variety of vocal noises to greet and warn each other, or to woo potential mates. Some of their vocalisations, which are called rumbles, are very low-pitched. So low in fact that humans can barely hear them. Due to the firm stance and weight of the elephants (which can reach 6,000kg), these waves travel not only through the air but also into the ground.</p>
<p>Elephants are thought to communicate over large distances – <a href="https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.530.8940&rep=rep1&type=pdf">up to several kilometres</a> in some cases. But it hasn’t been clear to scientists how important the seismic vibrations of their rumbles are in these long-distance chats. Is it just a coincidence that these sounds travel so far through the ground? Or is it something elephants actively exploit to stay in touch? </p>
<p><a href="http://rsif.royalsocietypublishing.org/doi/10.1098/rsif.2021.0264">We wanted to</a> find out. By deciphering the hidden information in these rumbles, we hoped they might also help us study and track elephants in future.</p>
<h2>Pinpointing elephants</h2>
<p>Working at Mpala Research Center in Kenya with computer scientists, earth scientists, conservationists and biologists, we set up microphones and seismometers around a watering hole known to be frequented by elephants. Seismometers pick up small underground vibrations and are typically used to measure earthquakes and explosions, some of which can be detected on the other side of the globe.</p>
<figure class="align-center ">
<img alt="A herd of elephants departing a lake." src="https://images.theconversation.com/files/411211/original/file-20210714-21-hb6rlw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/411211/original/file-20210714-21-hb6rlw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/411211/original/file-20210714-21-hb6rlw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/411211/original/file-20210714-21-hb6rlw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/411211/original/file-20210714-21-hb6rlw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/411211/original/file-20210714-21-hb6rlw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/411211/original/file-20210714-21-hb6rlw.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">
<figcaption>
<span class="caption">On the move: a herd of elephants leaving the watering hole.</span>
<span class="attribution"><span class="source">Beth Mortimer</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>For the first time ever, we found it was possible to accurately locate elephants by measuring vibrations in the ground caused by their low-pitched rumbles. Our devices recorded the rumbles they made at distances of up to 500 metres. </p>
<p>Comparing the signals at all the seismometers, we could estimate the animal’s location with an average accuracy of just a few metres. Surprisingly, the seismic sensors were slightly more accurate in pinpointing the elephants than the microphones. It’s quite common for scientists to track species using acoustic technology, but getting better results with signals through the ground could open a new way of monitoring wildlife.</p>
<h2>The future of wildlife monitoring</h2>
<p>It’s unknown how exactly elephants pick up these vibrations and how they decipher their meaning. But our study suggests that the seismic rumbles could announce the location of the vocalising animal to other elephants far away, despite the thick layers of earth that these waves pass through. </p>
<p>Whereas sound recordings can be interrupted by rain, wind and trees, seismic monitoring is relatively free of these types of interference. Where acoustic monitoring fails or gives bad results, seismic monitoring could be used instead. </p>
<p>This is helpful, as it’s important to know whether or not elephants are present in protected areas, or if they’ve wandered into places where they might be in danger, such as unguarded territories or towns and villages. Knowing this could allow rangers to respond quicker and prevent poaching, as well as prevent other kinds of conflict erupting between elephants and people.</p>
<figure class="align-center ">
<img alt="A large elephant amid African scrubland." src="https://images.theconversation.com/files/411212/original/file-20210714-27-1i8szsp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/411212/original/file-20210714-27-1i8szsp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/411212/original/file-20210714-27-1i8szsp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/411212/original/file-20210714-27-1i8szsp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/411212/original/file-20210714-27-1i8szsp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/411212/original/file-20210714-27-1i8szsp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/411212/original/file-20210714-27-1i8szsp.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">
<figcaption>
<span class="caption">Elephants can sometimes wander into trouble.</span>
<span class="attribution"><span class="source">Beth Mortimer</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Seismic monitoring could even be used to monitor hoofed animals like endangered species of giraffe and zebras. The seismic vibrations of their footsteps could help scientists study their group behaviour and how these species interact with their environment, without needing to tag them.</p>
<p><a href="https://doi.org/10.1016/j.cub.2018.03.062">Previous work</a> has shown that seismic recordings can accurately differentiate between the sounds made by elephants walking and their vocalisations. In future work, we hope to use this to develop AI algorithms that can detect what kind of wildlife is passing close to these sensors and what they are up to. This could help us monitor threatened or endangered species, count populations, and learn more about their movement and fascinating social behaviours.</p><img src="https://counter.theconversation.com/content/164368/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>African elephants stay in touch over large distances. We found out how.Michael Reinwald, Postdoctoral Research Associate in Zoology, University of OxfordBeth Mortimer, Royal Society University Research Fellow of Zoology, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1325262020-03-31T10:24:43Z2020-03-31T10:24:43ZCamera traps completed one of the most thorough surveys of African rainforest yet<figure><img src="https://images.theconversation.com/files/324258/original/file-20200331-65495-16o5ku5.png?ixlib=rb-1.1.0&rect=69%2C35%2C1057%2C1038&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">PNS Survey</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Tropical rainforests are the world’s richest land habitats for biodiversity, harbouring stunning numbers of plant and animal species. The Amazon and the Congo basins, together with Asian rainforests, represent only 6% of Earth’s land surface, and yet <a href="http://www.rain-tree.com/facts.htm">more than 50% of global biodiversity</a> can be found under their shade.</p>
<p>But observing even the most conspicuous species, such as elephants and apes, is still an extraordinarily difficult task. That’s not even mentioning all the secretive species that are protected by thick vegetation or darkness.</p>
<p>Camera traps have led a technological revolution in wildlife research, making it possible to study species without humans needing to be present. They can be left in the depths of a forest for weeks, taking pictures of anything that moves at any time of day or night.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/318423/original/file-20200303-66084-1cltf0o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/318423/original/file-20200303-66084-1cltf0o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/318423/original/file-20200303-66084-1cltf0o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/318423/original/file-20200303-66084-1cltf0o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/318423/original/file-20200303-66084-1cltf0o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/318423/original/file-20200303-66084-1cltf0o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/318423/original/file-20200303-66084-1cltf0o.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">Installing camera traps in Salonga National Park.</span>
<span class="attribution"><span class="source">Jonas Abana Eriksson/PNS Survey</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>From their advent three decades ago, camera traps have allowed scientists to discover species such as the <a href="https://www.nationalgeographic.com/news/2013/12/131219-elephant-shrew-gray-faced-sengi-animals-threatened-tanzania/">grey-faced sengi</a> – a new species of giant elephant shrew living in Tanzania – and the <a href="https://www.worldlandtrust.org/news/2018/03/annamite-striped-rabbit/">Annamite striped rabbit</a> in Vietnam. They revealed that <a href="https://theconversation.com/caught-on-camera-large-mammals-are-back-in-gabons-bateke-park-92527">lions</a> still wander the Bateke plateau in Gabon, ending speculation that they were locally extinct. They also <a href="https://news.mongabay.com/2018/12/for-elusive-javan-rhinos-camera-traps-are-a-benevolent-big-brother/">photographed</a> the offspring of the elusive Javan rhino, which scientists had thought had stopped breeding. With fewer than 100 individuals left, this gave hope that the species could be saved from extinction.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/323973/original/file-20200330-146678-t78dux.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/323973/original/file-20200330-146678-t78dux.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/323973/original/file-20200330-146678-t78dux.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/323973/original/file-20200330-146678-t78dux.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/323973/original/file-20200330-146678-t78dux.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/323973/original/file-20200330-146678-t78dux.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/323973/original/file-20200330-146678-t78dux.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">
<figcaption>
<span class="caption">The grey-faced sengi (<em>Rhynchocyon udzungwensis</em>) was discovered by camera traps in Tanzania.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Grey-faced_sengi#/media/File:Rhynchocyon_udzungwensis_Tanzania_F._Rovero.jpg">F Rovero/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Spotting stripes</h2>
<p>Camera traps are becoming essential for documenting forest species, assessing their <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0103300">distribution</a> and studying their <a href="https://www.sciencedirect.com/science/article/abs/pii/S0960982219301630">behaviour</a>, as well as <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2664.12432">counting what’s actually there</a>.</p>
<p>This latter measure, called animal abundance, is perhaps the most important information in wildlife conservation, as it allows researchers to assess <a href="https://www.iucnredlist.org/resources/summary-sheet">the conservation status of a species</a>. But until recently, camera traps could only be used to reliably estimate the abundance of animals with conspicuous markings, such as <a href="https://www.sciencedirect.com/science/article/pii/000632079400057W">big cats</a> with spots or stripes peculiar to single individuals.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/323978/original/file-20200330-146689-qnot5j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/323978/original/file-20200330-146689-qnot5j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/323978/original/file-20200330-146689-qnot5j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/323978/original/file-20200330-146689-qnot5j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/323978/original/file-20200330-146689-qnot5j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/323978/original/file-20200330-146689-qnot5j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/323978/original/file-20200330-146689-qnot5j.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">Big cats, like this African leopard (<em>Panthera pardus</em>), are among the simplest species to document with camera traps.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Leopard#/media/File:Leopard_(Panthera_pardus).jpg">Haplochromis/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Counting animals with camera traps remained impossible for the majority of species that lacked these conspicuous features, as the same individual could be counted twice by different cameras at different times. Methods that account for how animals <a href="https://doi.org/10.1111/j.1365-2664.2008.01473.x">move in</a> and <a href="https://projecteuclid.org/euclid.aoas/1372338474">use</a> their habitat were developed to help overcome the problem of detecting the same individual at different locations.</p>
<p>Another method, called <a href="https://doi.org/10.1111/2041-210X.12790">camera trap distance sampling</a> achieves the same result using a different approach. It subdivides the time cameras are active into “snapshots”, taking pictures at, for example, every fifth second in an hour. At a determined moment, an individual can only be spotted at one location, not elsewhere. Double counts are avoided, and researchers get the number of animals within the area surveyed by the cameras at a given snapshot.</p>
<p><a href="https://doi.org/10.1111/1365-2664.13602">We tested this new method</a> in one of the most remote areas of the planet - the southern part of <a href="https://salonga.org/">Salonga National Park</a>, a world heritage site in the Democratic Republic of the Congo. Here, rangers only had data on the park’s two flagship species – the <a href="https://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T12392A3339343.en">forest elephant</a> and the <a href="https://dx.doi.org/10.2305/IUCN.UK.2016-2.RLTS.T15932A17964305.en">bonobo</a>. Near to nothing was known about the other animals that were more difficult to track.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/318420/original/file-20200303-66078-1s3r8uo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/318420/original/file-20200303-66078-1s3r8uo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/318420/original/file-20200303-66078-1s3r8uo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/318420/original/file-20200303-66078-1s3r8uo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/318420/original/file-20200303-66078-1s3r8uo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/318420/original/file-20200303-66078-1s3r8uo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/318420/original/file-20200303-66078-1s3r8uo.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">A flagship species of Salonga National Park, bonobo populations are understudied in 70% of their range.</span>
<span class="attribution"><span class="source">Christian Ziegler/LKBP</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>What we found</h2>
<p>Five field teams walked a forest the size of Wales to deploy 160 camera traps in 743 places. This unprecedented effort produced more than 16,000 video clips, totalling 170 hours of animal footage and revealing 43 different animal species, including bonobos and elephants. </p>
<p>We also captured species rarely detected by human observers, such as the <a href="https://dx.doi.org/10.2305/IUCN.UK.2019-3.RLTS.T12762A123584478.en">giant ground pangolin</a>, threatened by extinction, the <a href="https://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T41593A45205341.en">cusimanses</a>, a genus of social mongooses, and the stunning <a href="https://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T22679430A92814166.en">Congo peafowl</a>, a vulnerable species that’s endemic to the country. </p>
<p>Where so far conservation of elusive species such as the <a href="https://dx.doi.org/10.2305/IUCN.UK.2015-2.RLTS.T18306A50663128.en">African golden cat</a>, the endemic <a href="https://dx.doi.org/10.2305/IUCN.UK.2019-3.RLTS.T865A17952193.en">Allen’s swamp monkey</a> and another elephant shrew, the <a href="https://dx.doi.org/10.2305/IUCN.UK.2015-2.RLTS.T42679A21290893.en">four-toed sengi</a>, had to be based on little to no data, we’re now able to estimate their abundance in the wild.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/318422/original/file-20200303-66069-etdazl.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/318422/original/file-20200303-66069-etdazl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/318422/original/file-20200303-66069-etdazl.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/318422/original/file-20200303-66069-etdazl.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/318422/original/file-20200303-66069-etdazl.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/318422/original/file-20200303-66069-etdazl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/318422/original/file-20200303-66069-etdazl.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/318422/original/file-20200303-66069-etdazl.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Nine of 43 species captured by camera traps in Salonga National Park, DRC.</span>
<span class="attribution"><span class="source">PNS Survey</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>For some species, the news from our findings were good. Our study revealed that the southern part of Salonga National Park alone harboured as many peafowls as were previously thought to be present in the whole country.</p>
<figure>
<iframe src="https://player.vimeo.com/video/402147632" width="500" height="281" frameborder="0" webkitallowfullscreen="" mozallowfullscreen="" allowfullscreen=""></iframe>
</figure>
<p>For other species, the results confirmed the need for greater protection. The 17,000 km² large and intact primary rain forest contains fewer than 1,000 giant pangolins. An alarming figure given the current <a href="https://conbio.onlinelibrary.wiley.com/doi/10.1111/conl.12389">illegal trade of pangolin scales</a>.</p>
<p>As the technology and methods of camera trap surveys improve, they’re becoming capable of monitoring a diverse range of wildlife, from the tiny elephant shrew to the mighty forest elephant. This gives an insight into the complex and delicate equilibrium of the rainforest community and the threats to its survival.</p><img src="https://counter.theconversation.com/content/132526/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This work was funded by Liverpool John Moores University and by the Kreditanstalt für Wiederaufbau (KfW Group) on behalf of the German Government and WWF Germany</span></em></p><p class="fine-print"><em><span>This work was funded by Liverpool John Moores University and by the Kreditanstalt für Wiederaufbau (KfW Group) on behalf of the German Government and WWF Germany. Barbara Fruth is affiliated with Bonobo Alive e.V. a non-profit association supporting conservation of the bonobo (Pan paniscus). </span></em></p>A new method of using camera traps has brought good and bad news for conservationists.Mattia Bessone, PhD Researcher in Conservation Biology, Liverpool John Moores UniversityBarbara Fruth, Associate Professor, Liverpool John Moores UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1340672020-03-18T18:05:42Z2020-03-18T18:05:42ZWe’ve just discovered two new shark species – but they may already be threatened by fishing<figure><img src="https://images.theconversation.com/files/321329/original/file-20200318-1942-12qjqmq.jpg?ixlib=rb-1.1.0&rect=37%2C29%2C4955%2C1684&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">One of the newly discovered sixgilled sawshark species (_Pliotrema kajae_).</span> <span class="attribution"><span class="source">Simon Weigmann</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Finding a species that’s entirely new to science is always exciting, and so we were delighted to be a part of <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0228791">the discovery of two new sixgill sawsharks</a> (called <em>Pliotrema kajae</em> and <em>Pliotrema annae</em>) off the coast of East Africa.</p>
<p>We know very little about sawsharks. Until now, only one sixgill species (<em>Pliotrema warreni</em>) was recognised. But we know sawsharks are carnivores, living on a diet of fish, crustaceans and squid. They use their serrated snouts to kill their prey and, with quick side-to-side slashes, break them up into bite-sized chunks. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/321317/original/file-20200318-37382-1kvg3zk.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/321317/original/file-20200318-37382-1kvg3zk.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/321317/original/file-20200318-37382-1kvg3zk.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/321317/original/file-20200318-37382-1kvg3zk.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/321317/original/file-20200318-37382-1kvg3zk.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/321317/original/file-20200318-37382-1kvg3zk.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/321317/original/file-20200318-37382-1kvg3zk.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/321317/original/file-20200318-37382-1kvg3zk.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 serrated snout of a sixgill sawshark (<em>Pliotrema annae</em>).</span>
<span class="attribution"><span class="source">Ellen Barrowclift-Mahon/Marine MEGAfauna Lab/Newcastle University.</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Sawsharks look similar to sawfish (which are actually rays), but they are much smaller. Sawsharks grow to around 1.5 metres in length, compared to 7 metres for a sawfish and they also have barbels (fish “whiskers”), which sawfish lack. Sawsharks have gills on the side of their heads, whereas sawfish have them on the underside of their bodies. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/321354/original/file-20200318-1953-1i2ndk3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/321354/original/file-20200318-1953-1i2ndk3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/321354/original/file-20200318-1953-1i2ndk3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/321354/original/file-20200318-1953-1i2ndk3.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/321354/original/file-20200318-1953-1i2ndk3.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/321354/original/file-20200318-1953-1i2ndk3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/321354/original/file-20200318-1953-1i2ndk3.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/321354/original/file-20200318-1953-1i2ndk3.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 sixgill sawshark (<em>Pliotrema annae</em>) turned on its side, showing gills and barbels.</span>
<span class="attribution"><span class="source">Ellen Barrowclift-Mahon</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Together with our colleagues, we discovered these two new sawsharks while researching small-scale fisheries that were operating off the coasts of Madagascar and Zanzibar. While the discovery of these extraordinary and interesting sharks is a wonder in itself, it also highlights how much is still unknown about biodiversity in coastal waters around the world, and how vulnerable it may be to poorly monitored and managed fisheries.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/321322/original/file-20200318-37441-1xec9fr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/321322/original/file-20200318-37441-1xec9fr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=549&fit=crop&dpr=1 600w, https://images.theconversation.com/files/321322/original/file-20200318-37441-1xec9fr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=549&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/321322/original/file-20200318-37441-1xec9fr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=549&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/321322/original/file-20200318-37441-1xec9fr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=690&fit=crop&dpr=1 754w, https://images.theconversation.com/files/321322/original/file-20200318-37441-1xec9fr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=690&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/321322/original/file-20200318-37441-1xec9fr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=690&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The three known species of sixgill sawshark. The two new species flank the original known species. From left to right: <em>Pliotrema kajae</em>, <em>Pliotrema warreni</em> (juvenile female) and <em>Pliotrema annae</em> (presumed adult female).</span>
<span class="attribution"><span class="source">Simon Weigmann</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Fishing in the dark</h2>
<p>Despite what their name might suggest, small-scale fisheries employ around 95% of the world’s fishers and are an <a href="https://theconversation.com/local-communities-play-outsized-but-overlooked-role-in-global-fisheries-123143">incredibly important source of food and money</a>, particularly in tropical developing countries. These fisheries usually operate close to the coast in some of the world’s most important biodiversity hotspots, such as coral reefs, mangrove forests and seagrass beds. </p>
<p>For most small-scale fisheries, there is very little information available about their fishing effort – that is, how many fishers there are, and where, when and how they fish, as well as exactly what they catch. Without this, it’s very difficult for governments to develop management programmes that can ensure sustainable fishing and protect the ecosystems and livelihoods of the fishers and the communities that depend on them.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/321316/original/file-20200318-37397-yjxu6s.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/321316/original/file-20200318-37397-yjxu6s.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/321316/original/file-20200318-37397-yjxu6s.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/321316/original/file-20200318-37397-yjxu6s.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/321316/original/file-20200318-37397-yjxu6s.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/321316/original/file-20200318-37397-yjxu6s.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/321316/original/file-20200318-37397-yjxu6s.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">Small-scale fishers of Zanzibar attending their driftnets.</span>
<span class="attribution"><span class="source">Per Berggren/Marine MEGAfauna Lab/Newcastle University</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>While the small-scale fisheries of East Africa and the nearby islands are not well documented, we do know that there are at least <a href="https://doi.org/10.1007/s11160-017-9494-x">half a million small-scale fishers using upwards of 150,000 boats</a>. That’s a lot of fishing. While each fisher and boat may not catch that many fish each day, with so many operating, it really starts to add up. Many use nets – either driftnets floating at the surface or gillnets, which are anchored close to the sea floor. Both are cheap but not very selective with what they catch. Some use longlines, which are effective at catching big fish, including sharks and rays.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/sharks-one-in-four-habitats-in-remote-open-ocean-threatened-by-longline-fishing-120849">Sharks: one in four habitats in remote open ocean threatened by longline fishing</a>
</strong>
</em>
</p>
<hr>
<p>In 2019, our team reported that catch records <a href="https://doi.org/10.1016/j.biocon.2018.12.024">were massively underreporting the number of sharks and rays caught</a> in East Africa and the nearby islands. With the discovery of two new species here – a global hotspot for shark and ray biodiversity – the need to properly assess the impact of small-scale fisheries on marine life is even more urgent.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/321319/original/file-20200318-37401-19jg3xr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/321319/original/file-20200318-37401-19jg3xr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/321319/original/file-20200318-37401-19jg3xr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=207&fit=crop&dpr=1 600w, https://images.theconversation.com/files/321319/original/file-20200318-37401-19jg3xr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=207&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/321319/original/file-20200318-37401-19jg3xr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=207&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/321319/original/file-20200318-37401-19jg3xr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=260&fit=crop&dpr=1 754w, https://images.theconversation.com/files/321319/original/file-20200318-37401-19jg3xr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=260&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/321319/original/file-20200318-37401-19jg3xr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=260&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"><em>Pliotrema kajae</em>, as it might look swimming in the subtropical waters of the western Indian Ocean.</span>
<span class="attribution"><span class="source">Simon Weigmann</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>How many other unidentified sharks and other species are commonly caught in these fisheries? There is a real risk of species going extinct before they’re even discovered. </p>
<p>Efforts to monitor and manage fisheries in this region, and globally, must be expanded to prevent biodiversity loss and to develop sustainable fisheries. There are simple methods available that can work on small boats where monitoring is currently absent, including using cameras to document what’s caught. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/321356/original/file-20200318-1972-n0x8np.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/321356/original/file-20200318-1972-n0x8np.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/321356/original/file-20200318-1972-n0x8np.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/321356/original/file-20200318-1972-n0x8np.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/321356/original/file-20200318-1972-n0x8np.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/321356/original/file-20200318-1972-n0x8np.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/321356/original/file-20200318-1972-n0x8np.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">A selection of landed fish – including sharks, tuna and swordfish.</span>
<span class="attribution"><span class="source">Per Berggren</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The discovery of two new sixgill sawsharks also demonstrates the value of scientists working with local communities. Without the participation of fishers we may never have found these animals. From simple assessments all the way through to developing methods to alter catches and manage fisheries, it’s our goal to make fisheries sustainable and preserve the long-term future of species like these sawsharks, the ecosystems they live in and the communities that rely on them for generations to come.</p><img src="https://counter.theconversation.com/content/134067/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Per Berggren receives funding from the Western Indian Ocean Marine Science Association (Grant Number MASMA/CP/2014/01).</span></em></p><p class="fine-print"><em><span>Andrew Temple receives funding from the Western Indian Ocean Marine Science Association (Grant Number MASMA/CP/2014/01).</span></em></p>Scientists thought there was only one sixgill sawshark species – until now.Per Berggren, Marine MEGAfauna Lab, Newcastle UniversityAndrew Temple, Postdoctoral Research Associate in Marine Biology, Newcastle UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1298422020-01-15T19:07:30Z2020-01-15T19:07:30ZWorst marine heatwave on record killed one million seabirds in North Pacific Ocean<figure><img src="https://images.theconversation.com/files/310011/original/file-20200114-151867-rskbgg.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2272%2C1704&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A common guillemot colony on the Farallon Islands, California.</span> <span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Common_murre#/media/File:Murre_colony.jpg">Duncan Wright/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>The common guillemot (known as the common murre in North America) breeds in both the Pacific and the Atlantic and is among the most abundant seabirds in the northern hemisphere. But like many other seabirds, its <a href="http://www.mosj.no/en/fauna/marine/guillemot.html">numbers have declined over the last few decades</a>. Part of that decline is due to the marine environment – a seabird’s home and hunting ground – becoming increasingly unpredictable and difficult to survive in.</p>
<p>Between the summer of 2015 and the spring of 2016, a marine heatwave swept the northern Pacific Ocean that was <a href="https://www.theguardian.com/science/2016/aug/15/the-blob-how-marine-heatwaves-are-causing-unprecedented-climate-chaos">hotter and lasted longer</a> than any since records began in 1870. Known as “<a href="https://www.fisheries.noaa.gov/feature-story/new-marine-heatwave-emerges-west-coast-resembles-blob">the blob</a>”, the heatwave caused sea surface temperatures along the Pacific coast of North America to rise by 1-2°C. That may sound trivial, but it was enough to cause massive disruption in the marine ecosystem. The fish that common guillemots normally eat, such as herring, sardine and anchovy, either died or moved into cooler waters elsewhere, leaving the guillemots with little to eat. As a result, many birds starved.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/310001/original/file-20200114-151839-43yzib.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/310001/original/file-20200114-151839-43yzib.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/310001/original/file-20200114-151839-43yzib.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/310001/original/file-20200114-151839-43yzib.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/310001/original/file-20200114-151839-43yzib.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/310001/original/file-20200114-151839-43yzib.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/310001/original/file-20200114-151839-43yzib.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/310001/original/file-20200114-151839-43yzib.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">On January 1 and 2 2016, 6,540 common guillemot carcasses were found washed ashore near Whitter, Alaska.</span>
<span class="attribution"><span class="source">David B. Irons</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>A new study has revealed that <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0226087">one million common guillemots died</a> due to the heatwave, and two thirds of them are thought to have been breeding adults. In a healthy population, about 95% of the breeding birds survive from one year to the next. But <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1600-048X.2012.05742.x">a bad year for adult survival causes big problems</a> for the total population.</p>
<p>This is because guillemots live up to 40 years and mature slowly, producing a single egg per annual clutch. A female may start breeding at the age of seven and continue to breed each year until she dies. Most seabirds live similar lives because the food on which they rear their offspring is often a long way from land. Ferrying food back to the breeding colony is what limits how many offspring they can rear in any one year. Rearing just a single chick at a time makes sense, but if many adult birds of reproductive age die, there are no new chicks to replace those birds that are lost, and so the population declines.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/marine-heatwaves-are-getting-hotter-lasting-longer-and-doing-more-damage-95637">Marine heatwaves are getting hotter, lasting longer and doing more damage</a>
</strong>
</em>
</p>
<hr>
<h2>Seabirds wrecked by ocean warming</h2>
<p>Researchers based the estimate of one million dead guillemots on the numbers of dead or dying birds that washed up between California and the Gulf of Alaska. A total of 62,000 birds were found on 6,000km of coastline, but not all birds that die at sea end up on beaches. <a href="http://eprints.glos.ac.uk/4410/">Previous studies have shown</a> that the number of birds actually found dead needs to be <a href="https://pdfs.semanticscholar.org/cba4/c94c76196b532c03f25b7bc82a4f1bca0364.pdf?_ga=2.85735257.1933956107.1579073925-1675840455.1579073925">multiplied by at least seven times</a> – and possibly as much as <a href="https://www.researchgate.net/publication/278196709_Bird_mortality_from_the_Deepwater_Horizon_oil_spill_II_Carcass_sampling_and_exposure_probability_in_the_coastal_Gulf_of_Mexico">several hundred times</a> – to find the minimum estimate of the total numbers dead. That means that “one million dead seabirds” might actually be a conservative guess.</p>
<p>According to the new study, breeding populations in the Gulf of Alaska suffered a 10-20% decrease in numbers. Complete breeding failure, where birds either failed to lay eggs or failed to rear any chicks, was reported at 22 regularly monitored guillemot colonies in Alaska during the breeding seasons of 2015, 2016 and 2017. Complete breeding failure is extremely unusual among guillemots and it’s a clear sign that food is in extremely short supply.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/310202/original/file-20200115-151862-14zmt5q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/310202/original/file-20200115-151862-14zmt5q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/310202/original/file-20200115-151862-14zmt5q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=464&fit=crop&dpr=1 600w, https://images.theconversation.com/files/310202/original/file-20200115-151862-14zmt5q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=464&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/310202/original/file-20200115-151862-14zmt5q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=464&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/310202/original/file-20200115-151862-14zmt5q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=583&fit=crop&dpr=1 754w, https://images.theconversation.com/files/310202/original/file-20200115-151862-14zmt5q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=583&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/310202/original/file-20200115-151862-14zmt5q.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"></a>
<figcaption>
<span class="caption">Temperatures in the northeast Pacific Ocean broke records during the 2015-2016 heatwave.</span>
<span class="attribution"><a class="source" href="https://www.ncdc.noaa.gov/temp-and-precip/global-maps/201507?products[]=map-land-sfc-mntp&products[]=map-blended-mntp&products[]=map-prcp&products[]=map-percentile-mntp&products[]=map-percentile-prcp&products[]=map-prcp-percent#global-maps-select">NOAA</a></span>
</figcaption>
</figure>
<p>The appearance of unusually high numbers of dead birds washed up on the shoreline is <a href="https://myriadbirds.com/2014/03/03/wrecks/">referred to as a “wreck”</a>. Wrecks of common guillemots and related species such as puffins have been known about for many years. These population crashes may be a regular aspect of guillemot biology, but this one was far larger and over a much wider geographic area than any wreck seen before. </p>
<p>In most cases, wrecks are the result of persistent stormy conditions, disrupting the availability of fish on which seabirds like guillemots and puffins depend. When seas are rough and the weather harsh, the increased energy demands can kill many birds. The most recent wreck in the UK and western Europe occurred in the spring of 2014, and it <a href="http://www.seabirdgroup.org.uk/journals/seabird-29/seabird-29-22.pdf?LMCL=C1kfQy">killed at least 50,000 birds</a>, mainly common guillemots and Atlantic puffins.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/climate-change-is-causing-mass-die-offs-in-seabirds-such-as-puffins-117803">Climate change is causing mass 'die-offs' in seabirds such as puffins</a>
</strong>
</em>
</p>
<hr>
<p>The common guillemot populations in the Pacific and western Europe will probably recover from both of these recent wrecks, providing there’s no further turmoil, but there’s no room for complacency. The only way scientists will know if populations have recovered is by monitoring the birds. It’s an activity that is generally regarded as the lowest form of scientific endeavour, but one that’s absolutely vital in a world of declining wildlife.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/310200/original/file-20200115-151887-1hba7tb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/310200/original/file-20200115-151887-1hba7tb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=591&fit=crop&dpr=1 600w, https://images.theconversation.com/files/310200/original/file-20200115-151887-1hba7tb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=591&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/310200/original/file-20200115-151887-1hba7tb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=591&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/310200/original/file-20200115-151887-1hba7tb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=743&fit=crop&dpr=1 754w, https://images.theconversation.com/files/310200/original/file-20200115-151887-1hba7tb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=743&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/310200/original/file-20200115-151887-1hba7tb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=743&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Tim Birkhead and his field assistant Dr Jess Meade on Skomer in 2012.</span>
<span class="attribution"><span class="source">Tim Birkhead</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>I’ve been studying and monitoring the number of common guillemots on Skomer Island, Wales since 1972. In that time, I’ve realised <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1111/j.1365-2656.2008.01421.x">how essential this work is</a> to understanding how guillemot populations work. Beach counts of dead seabirds allow scientists to detect unusual events, but these counts are meaningless without information on the overall size of the population. Without regular monitoring of seabird colonies on North America’s west coast, the researchers wouldn’t have known what proportion of the total population died, and would have missed the total breeding failures in the Alaskan colonies.</p>
<p>The North Pacific common guillemot wreck was unprecedented for the sheer numbers of birds killed, and the vast region over which it occurred. But the marine heatwave that caused it may be just a taste of what is to come for seabirds around the world as climate change accelerates.</p>
<hr>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=140&fit=crop&dpr=1 600w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=140&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=140&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=176&fit=crop&dpr=1 754w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=176&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=176&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/imagine-newsletter-researchers-think-of-a-world-with-climate-action-113443?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=Imagineheader1129842">Click here to subscribe to our climate action newsletter. Climate change is inevitable. Our response to it isn’t.</a></em></p><img src="https://counter.theconversation.com/content/129842/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tim Birkhead has in the past received funding from the Natural Environment Research Council; Countryside Council for Wales, University of Sheffield.. </span></em></p>As well as a stark warning about climate change, the disaster underlines the importance of wildlife monitoring.Tim Birkhead, Emeritus Professor of Zoology, University of SheffieldLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1202112019-07-14T18:46:32Z2019-07-14T18:46:32ZMaking deer fair game for unlicensed hunting is the right step for New South Wales<figure><img src="https://images.theconversation.com/files/283798/original/file-20190712-173376-1l2abyh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The fate of deer carcasses is a crucial consideration in monitoring the success of future culling.</span> <span class="attribution"><span class="source">Emma Spencer</span>, <span class="license">Author provided</span></span></figcaption></figure><p>The New South Wales government <a href="https://www.theland.com.au/story/6266252/nsw-set-to-relax-shooting-rules-on-feral-deer/">last week revealed plans</a> to ease shooting restrictions on feral deer. If the plans go ahead, deer will be stripped of their status as a game animal and will no longer be afforded protection under the state’s <a href="https://www.legislation.nsw.gov.au/#/view/act/2002/64/part3/div2/sec16">animal control laws</a>. </p>
<p>This will mean that a <a href="https://www.dpi.nsw.gov.au/hunting/hunting-licences">game hunting licence</a> would not be required for recreational, commercial and professional hunting of deer species. Restrictions on how and when deer can be hunted would also be lifted. </p>
<p>Feral deer will be treated the same as other pest animals in NSW, including red foxes, feral cats and rabbits.</p>
<h2>Deer are already considered a pest</h2>
<p>Last year the NSW government <a href="https://www.lls.nsw.gov.au/biosecurity/pestplan">approved 11 regional pest animal plans</a>, each of which declared deer as a priority pest species. Several hunting regulations have <a href="https://www.dpi.nsw.gov.au/hunting/game-and-pests/managing-wild-deer-in-nsw">already been suspended</a> to manage abundant deer populations, and in February 2019 the government announced a A$9 million deer control program described as the <a href="https://www.abc.net.au/news/rural/2019-02-28/deer-mangement-plan-launched-nsw/10858226">most extensive of its kind</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/oh-deer-a-tricky-conservation-problem-for-tasmania-43702">Oh deer: a tricky conservation problem for Tasmania</a>
</strong>
</em>
</p>
<hr>
<p>Removing the game status of deer is the next logical step towards controlling existing deer numbers in NSW, and slowing their spread to new areas. Deer currently cover 17% of NSW, and this area has <a href="https://www.dpi.nsw.gov.au/biosecurity/vertebrate-pests/pest-animals-in-nsw/wild-deer/wild-deer">more than doubled since 2009</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/283799/original/file-20190712-173329-1u2wysx.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/283799/original/file-20190712-173329-1u2wysx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/283799/original/file-20190712-173329-1u2wysx.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=420&fit=crop&dpr=1 600w, https://images.theconversation.com/files/283799/original/file-20190712-173329-1u2wysx.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=420&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/283799/original/file-20190712-173329-1u2wysx.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=420&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/283799/original/file-20190712-173329-1u2wysx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=528&fit=crop&dpr=1 754w, https://images.theconversation.com/files/283799/original/file-20190712-173329-1u2wysx.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=528&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/283799/original/file-20190712-173329-1u2wysx.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=528&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Deer now cover 17% of NSW.</span>
<span class="attribution"><span class="source">NSW Dept of Primary Industries</span></span>
</figcaption>
</figure>
<p>Without urgent and effective control, the deer population could spread <a href="https://www.publish.csiro.au/wr/fulltext/WR16148">throughout the entire state and beyond</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/283704/original/file-20190711-173338-1iwa7h7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/283704/original/file-20190711-173338-1iwa7h7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=343&fit=crop&dpr=1 600w, https://images.theconversation.com/files/283704/original/file-20190711-173338-1iwa7h7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=343&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/283704/original/file-20190711-173338-1iwa7h7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=343&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/283704/original/file-20190711-173338-1iwa7h7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=431&fit=crop&dpr=1 754w, https://images.theconversation.com/files/283704/original/file-20190711-173338-1iwa7h7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=431&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/283704/original/file-20190711-173338-1iwa7h7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=431&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Effective control is needed to stop the spread of feral deer in Australia.</span>
<span class="attribution"><span class="source">Emma Spencer</span></span>
</figcaption>
</figure>
<h2>The impacts of deer</h2>
<p>Feral deer remain one of Australia’s least studied introduced mammals. Yet the evidence shows they have a substantial impact on Australia’s ecosystems and agriculture. </p>
<p>Since 2005, grazing and environmental damage by feral deer has been listed as a <a href="https://www.environment.nsw.gov.au/Topics/Animals-and-plants/Threatened-species/NSW-Threatened-Species-Scientific-Committee/Determinations/Final-determinations/2004-2007/Herbivory-and-environmental-degradation-caused-by-feral-deer-key-threatening-process-listing">key threatening process under NSW legislation</a>. Deer are known to <a href="https://search.informit.com.au/documentSummary;dn=864886033639373;res=IELHSS">graze on threatened plant species</a>, and also cause erosion and soil compaction. They damage pasture; destroy fences and contaminate water sources; harm trees via antler rubbing; rip up the ground during rutting season; and potentially contribute to the spread of livestock diseases. </p>
<p>Deer are a threat to humans too. The Illawarra region south of Sydney, a hotspot for deer activity, <a href="https://invasives.org.au/blog/feral-deer-putting-nsw-drivers-at-risk/">has seen one death and multiple serious injuries</a> between 2003 and 2017 due to vehicle collisions with deer. </p>
<p>Deer can also carry <a href="https://www.publish.csiro.au/wr/fulltext/WR16148">pathogens that cause human disease</a> such as Leptospirosis and Cryptosporidium. </p>
<h2>Choosing the right control method</h2>
<p>Ground-based shooting is the main way to manage deer in the urban fringes, regional areas and national parks. Unfortunately, coordinated ground shoots <a href="https://www.publish.csiro.au/wr/fulltext/WR16148">have only been effective for areas of less than 1,000 hectares</a>, and there is no evidence that uncoordinated shooting by recreational hunters actually works to control deer on a widespread basis. </p>
<p>Aerial shooting can potentially be more successful over large tracts of land, but may not be a good option when tree cover is high and visibility is low. Poison baiting could help, although there is no method available to deliver baits safely, effectively and specifically to deer. </p>
<p>Irrespective of the control method, a coordinated approach is needed. We need a strategy that not only controls deer where damage is worst, but also prevents their spread to new areas. This will require NSW to work closely with the ACT and Victoria. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/283694/original/file-20190711-173351-1y7pz99.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/283694/original/file-20190711-173351-1y7pz99.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=418&fit=crop&dpr=1 600w, https://images.theconversation.com/files/283694/original/file-20190711-173351-1y7pz99.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=418&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/283694/original/file-20190711-173351-1y7pz99.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=418&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/283694/original/file-20190711-173351-1y7pz99.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=525&fit=crop&dpr=1 754w, https://images.theconversation.com/files/283694/original/file-20190711-173351-1y7pz99.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=525&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/283694/original/file-20190711-173351-1y7pz99.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=525&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A red fox feeds on a culled feral deer.</span>
<span class="attribution"><span class="source">Emma Spencer</span></span>
</figcaption>
</figure>
<p>Rigorous monitoring will also be vital. This is important to gauge success (how many deer were culled, and the ethics of shooting, trapping and baiting), and to determine whether the control efforts have unintended impacts on the environment, such as deer carcasses providing <a href="https://www.weeklytimesnow.com.au/news/victoria/deer-cull-carcasses-an-allyoucaneat-buffet-for-wild-dogs/news-story/2d0bbdb22da3ef97b5e193f78a8b160a">food for scavenging pests</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-protected-pest-deer-in-australia-11452">The protected pest: deer in Australia</a>
</strong>
</em>
</p>
<hr>
<p>Scavenging pests have been observed feeding on carcasses, but whether culling deer and other feral animals actually increases their abundance and impacts is unknown. Carcasses also provide a source of food for native scavengers such as eagles and ravens, and are integral to the structure and function of ecosystems. </p>
<p>The negative and positive impacts of deer culling on the broader ecosystem therefore needs consideration when developing and implementing monitoring plans. NSW can be the leader in this regard, starting from day one after removing the status of the deer as a game species.</p><img src="https://counter.theconversation.com/content/120211/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Thomas Newsome receives funding from the Australian Government, Hermon-Slade Foundation, Australia Pacific Science Foundation, National Geographic, and Australian Academy of Science. </span></em></p><p class="fine-print"><em><span>Emma Spencer receives funding from the Australian Government, Australian Academy of Science and Holsworth Wildlife Research Endowment.</span></em></p>The NSW government has announced plans to remove feral deer from its list of official game animals. With careful monitoring, the resulting free-for-all could help curb their booming numbers.Thomas Newsome, Lecturer, University of SydneyEmma Spencer, PhD candidate, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/960862018-07-13T10:24:32Z2018-07-13T10:24:32ZScientist at work: Identifying individual gray wolves by their howls<figure><img src="https://images.theconversation.com/files/227222/original/file-20180711-27015-1dr73z1.jpg?ixlib=rb-1.1.0&rect=164%2C226%2C2079%2C1483&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Each wolf calls with its own 'voice.'</span> <span class="attribution"><span class="source">Angela Dassow</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Love them or hate them, wolves are vital members of natural ecosystems and the health of a wolf population can be an important factor in <a href="https://www.livingwithwolves.org/about-wolves/why-wolves-matter/">maintaining balance</a> among species. Wolf populations are growing in North America – the Great Lakes region in particular now supports over <a href="https://www.fws.gov/midwest/wolf/aboutwolves/wolfpopus.htm">3,700 individuals</a>. Keeping track of wolf pack movements is important for reducing human-wolf conflicts which can arise when packs move too close to ranches.</p>
<p>The traditional way to track wolves involves setting traps, sedating and then radio-collaring individual animals. While effective, this approach is time intensive and expensive, and entails risks for the animals. </p>
<p>I was fortunate to participate in this entire process firsthand as an undergraduate student. During the summer trapping seasons, I became familiar with each of the wolves in the central forest region of Wisconsin. This experience led to several conversations with the wildlife biologists in the area about whether wolf howls could be used to help identifying non-radio-collared pack members.</p>
<p><audio preload="metadata" controls="controls" data-duration="5" data-image="" data-title="Howl from a wild adult wolf, recorded in central Wisconsin by author Angela Dassow and Carthage College biology students, Cara Hull and Caitlin McCombe." data-size="119400" data-source="" data-source-url="" data-license="Author provided" data-license-url="">
<source src="https://cdn.theconversation.com/audio/1199/south-bluff-filtered-howl.mp3" type="audio/mpeg">
</audio>
<div class="audio-player-caption">
Howl from a wild adult wolf, recorded in central Wisconsin by author Angela Dassow and Carthage College biology students, Cara Hull and Caitlin McCombe.
<span class="attribution"><span class="license">Author provided</span><span class="download"><span>117 KB</span> <a target="_blank" href="https://cdn.theconversation.com/audio/1199/south-bluff-filtered-howl.mp3">(download)</a></span></span>
</div></p>
<p>This question remained a fun thought experiment for many years. Now <a href="https://www.carthage.edu/live/profiles/1488-angela-dassow">as a biology professor</a> who specializes in <a href="http://ocr.org/learn/bioacoustics/">bioacoustics</a>, I’ve been able to turn that thought experiment into a full research question: Can we use acoustic features to identify individual wolves in the wild? </p>
<h2>Downsides of radio collaring</h2>
<p>Because of the many challenges involved in radio collaring an animal, it would be useful to have a new way to identify and track wild wolves.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/227472/original/file-20180712-27024-1pztro3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/227472/original/file-20180712-27024-1pztro3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/227472/original/file-20180712-27024-1pztro3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=568&fit=crop&dpr=1 600w, https://images.theconversation.com/files/227472/original/file-20180712-27024-1pztro3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=568&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/227472/original/file-20180712-27024-1pztro3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=568&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/227472/original/file-20180712-27024-1pztro3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=714&fit=crop&dpr=1 754w, https://images.theconversation.com/files/227472/original/file-20180712-27024-1pztro3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=714&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/227472/original/file-20180712-27024-1pztro3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=714&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 U.S. Fish and Wildlife Service employee fastens a radio collar onto a sedated female gray wolf.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/usfwsmtnprairie/8488974469">Lori Iverson/USFWS</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>To successfully set a trap, wildlife managers must first spend days, if not weeks, scouting for signs of wolves. Once they’ve identified a suitable area, they set traps that must be checked every 24 hours. If successful, the animal needs to be sedated before it can be removed from the trap – which can be stressful both for the wolf and the researchers involved.</p>
<p>A sedated wolf cannot regulate its body temperature and overheating can become an issue on hot days. Human handling of a sedated wolf can also be stressful on the pack members that are often nearby, observing the scene. Even after an animal is successfully radio-collared and released, it’s still vulnerable to predators while the sedative wears off.</p>
<p>In spite of these risks, radio-collaring has been the standard way to track populations because each collar’s radio-transmitter frequency acts as a unique identifier of an individual. Researchers can then use aerial surveys where a pilot searches for the collared animal or ground surveys where a field crew drives throughout a pack territory searching for feedback from the radio signal. This method is used to track a wide array of animals, including turtles, birds, bats, whales, fish, snakes and more.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/223229/original/file-20180614-32319-1juwm5r.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/223229/original/file-20180614-32319-1juwm5r.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/223229/original/file-20180614-32319-1juwm5r.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/223229/original/file-20180614-32319-1juwm5r.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/223229/original/file-20180614-32319-1juwm5r.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/223229/original/file-20180614-32319-1juwm5r.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/223229/original/file-20180614-32319-1juwm5r.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/223229/original/file-20180614-32319-1juwm5r.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">Angela Dassow and Cara Hull survey a road in central Wisconsin for signs of wolves.</span>
<span class="attribution"><span class="source">Caitlin McCombe</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Listening to learn who’s who</h2>
<p>In 2013, behavioral ecologist <a href="https://scholar.google.com/citations?user=CZyS1lMAAAAJ&hl=en&oi=sra">Holly Root-Gutteridge</a> and her colleagues successfully demonstrated that they could <a href="https://doi.org/10.1080/09524622.2013.817318">identify individual wolves in captivity using acoustic features</a>. Their research provided evidence that it made sense to test whether vocal identification in wild animals is possible.</p>
<p>So with the support of the <a href="https://www.carthage.edu/sure/">Summer Undergraduate Research Experience</a> at <a href="https://www.carthage.edu/">Carthage College</a>, volunteers from the <a href="http://www.timberwolfinformation.org/">Timber Wolf Information Network</a>, and wildlife managers at <a href="https://dnr.wi.gov/topic/lands/wildlifeareas/sandhill/">Sandhill Wildlife Area</a> in Babcock, Wisconsin, my undergraduate students Cara Hull and Caitlin McCombe and I began to record wolves in the wild.</p>
<p>It would be an understatement to say fieldwork can be challenging. On any given day, there can be daunting weather fluctuations. Biting insects, especially mosquitoes and deer flies, are abundant in wolf habitat. We had to constantly check ourselves for ticks. And then of course comes the actual fieldwork. </p>
<p>Wolves naturally avoid coming near people, but the best quality recordings are made up close to where the animals are producing the sounds. To get close with our audio equipment, we had to track the wolves every day to learn where they’d most recently been within their large territories. That’s how we’d establish a starting point for our nightly recording sessions.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/223228/original/file-20180614-32304-mgakkr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/223228/original/file-20180614-32304-mgakkr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/223228/original/file-20180614-32304-mgakkr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=765&fit=crop&dpr=1 600w, https://images.theconversation.com/files/223228/original/file-20180614-32304-mgakkr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=765&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/223228/original/file-20180614-32304-mgakkr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=765&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/223228/original/file-20180614-32304-mgakkr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=962&fit=crop&dpr=1 754w, https://images.theconversation.com/files/223228/original/file-20180614-32304-mgakkr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=962&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/223228/original/file-20180614-32304-mgakkr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=962&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fresh track from an adult gray wolf.</span>
<span class="attribution"><span class="source">Angela Dassow</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Conducting a daily survey of wolf habitat requires driving or walking down every possible path within a wolf’s territory. Signs of activity could include fresh footprints or tracks. This can tell us how many animals were in the area and what direction they were heading.</p>
<p>Large dogs can produce footprints that are similar in size to those of wolves; but the pattern of tracks can be distinguished based on the placement of their feet and the directness of the chosen route. Dogs have a tendency to wander more, while wolves will walk in a more efficient straight line.</p>
<p>In addition to tracks, we conduct a survey of fresh scat. It’s not glamorous, but examining their feces provides valuable information about what the wolves have been eating and how recently they walked along a trail.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/223050/original/file-20180613-32323-8i1dwh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/223050/original/file-20180613-32323-8i1dwh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/223050/original/file-20180613-32323-8i1dwh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/223050/original/file-20180613-32323-8i1dwh.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/223050/original/file-20180613-32323-8i1dwh.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/223050/original/file-20180613-32323-8i1dwh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/223050/original/file-20180613-32323-8i1dwh.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/223050/original/file-20180613-32323-8i1dwh.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Carthage College biology students Cara Hull and Caitlin McCombe conduct a howl survey in central Wisconsin.</span>
<span class="attribution"><span class="source">Angela Dassow</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Using the information from our daytime survey, we plan a shorter nighttime howling route. Howling is a natural behavior during the evenings, when wolves call to signal that a territory is occupied. At each stopping point on our route, a researcher must get out of the vehicle and howl while another researcher records with a microphone any wolf responses, announcing their presence or defending territory. If we are successful in eliciting a response, we continue in its direction until we get as close as possible.</p>
<p>Use of lights is discouraged since it can deter the wolves from calling again, so we needed to feel our way through the forest at night. Personally, I think it is incredibly exciting to be walking down a trail in the dark and have a wolf walk within feet of where I am. It may sound scary, but we are not in any danger since wolves prefer to avoid contact with humans. During our month-long survey, we were fortunate to experience two close wolf encounters. </p>
<h2>Back in the lab, analyzing the calls</h2>
<p>With the howls recorded, we can return to the lab to analyze our findings using audio software.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/223230/original/file-20180614-32316-16wyrn2.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/223230/original/file-20180614-32316-16wyrn2.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/223230/original/file-20180614-32316-16wyrn2.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/223230/original/file-20180614-32316-16wyrn2.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/223230/original/file-20180614-32316-16wyrn2.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/223230/original/file-20180614-32316-16wyrn2.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/223230/original/file-20180614-32316-16wyrn2.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/223230/original/file-20180614-32316-16wyrn2.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">Acoustic properties are measured using Adobe Audition.</span>
<span class="attribution"><span class="source">Angela Dassow</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>We were able to isolate 21 howls from two adult wolves over two evenings. For each howl, we made six types of frequency measurements and two types of duration measurements. Frequency is how high or low the pitch of the howl sounds and duration is the length of time the howl lasted.</p>
<p>For wild gray wolves, we found that the maximum frequency – that is, the highest sound an animal produced – and the frequency at the end of the howl were the two variables that were most individualistic. For captive wolves, it was different. The lowest frequency an individual produced – what in acoustics is called their fundamental frequency – and the loudness of its calls were the factors that best differentiated among the captive individuals.</p>
<p>The differences in useful identification information between wild and captive howls are likely a reflection of signal quality. The captive recordings are much clearer than what we were able to record in the wild, where we were typically at least half a mile away from the wolves; the signal degrades with distance. As signal quality declines, maximum frequency and end frequency become more useful in individual identification.</p>
<p>Based on our findings and previous research, it is possible to monitor gray wolf populations using non-invasive methods. To do so effectively, researchers would need to record known individuals in a particular area. Once they’ve built up a database of known individuals’ howls, they can conduct nightly surveys. Comparing new recordings to those in the audio library would let them determine which individuals are in an area. </p>
<p>While radio-collaring procedures may still be useful in some cases, vocal identification is a promising alternative for monitoring individuals. Acoustic surveys are still a time-consuming process, but they eliminate the time needed to trap individuals and remove any possibility of accidentally injuring an animal in a trap. Additionally, once researchers gather a database of positively identified individuals, they can use remote monitoring stations to record howls, thus reducing the amount of time spent conducting nightly surveys. Acoustic monitoring could potentially track all the wolves in multiple packs whereas radio-collaring is typically used to track a single member in select packs.</p><img src="https://counter.theconversation.com/content/96086/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Angela Dassow 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>Tracking wild animals can provide lots of valuable data. New research suggests audio recordings of wild wolves can replace the typical radio collars, which can be expensive and intrusive.Angela Dassow, Assistant Professor of Biology, Carthage CollegeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/864762018-02-20T05:36:05Z2018-02-20T05:36:05ZNow you see us: how casting an eerie glow on fish can help count and conserve them<figure><img src="https://images.theconversation.com/files/206516/original/file-20180215-124899-101fonp.jpg?ixlib=rb-1.1.0&rect=5%2C0%2C3988%2C2994&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Biofluorescence makes researching cryptic species such as this Lizardfish easier and less harmful.</span> <span class="attribution"><span class="source">Maarten De Brauwer</span>, <span class="license">Author provided</span></span></figcaption></figure><p>News stories about fish often focus either on large fish like <a href="https://theconversation.com/sharkathon-2017-is-here-how-to-watch-it-like-a-scientist-80370">sharks</a>, or on <a href="https://theconversation.com/heres-why-your-sustainable-tuna-is-also-unsustainable-83560">tasty seafood</a>. So it might come as a surprise that more than half of the fish on coral reefs are tiny and well camouflaged. </p>
<p>This naturally makes them hard to find, and as a result we know very little about these so-called “cryptic” species. </p>
<p>Now my colleagues and I have developed a new method to make it easier to study these fish. As we <a href="http://onlinelibrary.wiley.com/doi/10.1111/cobi.13033/full">report in the journal Conservation Biology</a>, many of these species are “biofluorescent” – if you shine blue light on them they will reflect it back in a different colour. This makes them a whole lot easier to spot.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/206524/original/file-20180215-131003-1ttjylr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/206524/original/file-20180215-131003-1ttjylr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/206524/original/file-20180215-131003-1ttjylr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/206524/original/file-20180215-131003-1ttjylr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/206524/original/file-20180215-131003-1ttjylr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/206524/original/file-20180215-131003-1ttjylr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/206524/original/file-20180215-131003-1ttjylr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/206524/original/file-20180215-131003-1ttjylr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Cryptic fish such as the Moray species are easily detectible using this new method.</span>
<span class="attribution"><span class="source">Maarten De Brauwer</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/dazzling-or-deceptive-the-markings-of-coral-reef-fish-12312">Dazzling or deceptive? The markings of coral reef fish</a>
</strong>
</em>
</p>
<hr>
<p>Marine biologists try to collect essential information about species so as to help protect them. One of the most important pieces of information is estimating how many of these cryptic species are out there.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/teJz4MGJQy0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Now you ‘sea’ them.</span></figcaption>
</figure>
<p>These cryptic fishes are more important for us than people realise. They are highly diverse and hugely important to coral reef health. They are also food for the fish we like to eat, and provide <a href="https://www.sciencedirect.com/science/article/pii/S0308597X17300581">incomes for thousands of people</a> through scuba diving tourism. </p>
<p>These small fishes <a href="http://www.cell.com/current-biology/fulltext/S0960-9822(17)30350-0">live fast and die young</a>, reproducing quickly and being eaten by bigger fish almost as quickly. We do know that some species are dwindling in number. The Knsyna seahorse in South Africa is <a href="http://www.iucnredlist.org/details/10056/0">in danger of extinction</a>, while many cryptic goby species in the Caribbean were being <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0177179">eaten by invasive lionfish</a> before they had even been described, let alone counted. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/206520/original/file-20180215-124905-1hojs1t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/206520/original/file-20180215-124905-1hojs1t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/206520/original/file-20180215-124905-1hojs1t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/206520/original/file-20180215-124905-1hojs1t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/206520/original/file-20180215-124905-1hojs1t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/206520/original/file-20180215-124905-1hojs1t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1006&fit=crop&dpr=1 754w, https://images.theconversation.com/files/206520/original/file-20180215-124905-1hojs1t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1006&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/206520/original/file-20180215-124905-1hojs1t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1006&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Some cryptic species, such as this thorny seahorse (Hippocampus histrix) are more popular than other species in aquaria, for divers and as the subjects in movies.</span>
<span class="attribution"><span class="source">Maarten De Brauwer</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Because cryptic fishes are so easy to miss, their total abundance is likely to be underestimated. When attempting to survey their populations, scientists generally had to resort to using chemicals to stun or kill the fish, after which they are collected and counted. This method is efficient, but it is not ideal to kill members of species that might be endangered.</p>
<p>Developing an efficient, non-destructive way to survey fish would benefit researchers and conservationists, and this is where biofluorescence comes in.</p>
<h2>Biofluorescence or bioluminescence?</h2>
<p>Biofluorescence is very different to <a href="http://www.luminescentlabs.org/science.html">bioluminescence</a>, the chemical process by which animals such as deep-sea fish or fireflies produce their own light. In contrast, <a href="http://www.luminescentlabs.org/science.html">biofluorescent animals</a> absorb light and reflect it as a different colour, so this process needs an external source of light. </p>
<p>Biofluorescence is most easily observed in corals, where it has been used to <a href="https://link.springer.com/article/10.1007/s00338-005-0495-1?no-access=true">find small juveniles</a>. In the ocean, biofluorescence can be observed by using a strong blue light source, combined with a diving mask fitted with a yellow filter.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/207057/original/file-20180220-116365-1i4hsoc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/207057/original/file-20180220-116365-1i4hsoc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/207057/original/file-20180220-116365-1i4hsoc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/207057/original/file-20180220-116365-1i4hsoc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/207057/original/file-20180220-116365-1i4hsoc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/207057/original/file-20180220-116365-1i4hsoc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/207057/original/file-20180220-116365-1i4hsoc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/207057/original/file-20180220-116365-1i4hsoc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Before… a scorpionfish captured without showing its biofluorescence, camouflaged against the rocks.</span>
<span class="attribution"><span class="source">Maarten De Brauwer</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/207058/original/file-20180220-116351-l87wb0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/207058/original/file-20180220-116351-l87wb0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/207058/original/file-20180220-116351-l87wb0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/207058/original/file-20180220-116351-l87wb0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/207058/original/file-20180220-116351-l87wb0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/207058/original/file-20180220-116351-l87wb0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/207058/original/file-20180220-116351-l87wb0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/207058/original/file-20180220-116351-l87wb0.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">And after… the same scorpionfish in an image that captures its biofluorescence.</span>
<span class="attribution"><span class="source">Maarten De Brauwer</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p><a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0083259">Recent research</a> showed that biofluorescence is more common among fish than we previously realised. This prompted us to investigate whether biofluorescence can be used to detect cryptic fishes.</p>
<h2>On the glow</h2>
<p>We tested 230 fish species through the <a href="https://en.wikipedia.org/wiki/Coral_Triangle">Coral Triangle</a> to Australia’s north, and found that biofluorescence is indeed widespread in cryptic fish species. </p>
<p>It is so common, in fact, that the probability of a fish being biofluorescent is 70.9 times greater for cryptic species than for highly visible species. </p>
<p>But can this actually be used to improve our detection of cryptic fish species? The answer is yes. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/207056/original/file-20180220-116343-frh4lv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/207056/original/file-20180220-116343-frh4lv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/207056/original/file-20180220-116343-frh4lv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/207056/original/file-20180220-116343-frh4lv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/207056/original/file-20180220-116343-frh4lv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/207056/original/file-20180220-116343-frh4lv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/207056/original/file-20180220-116343-frh4lv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/207056/original/file-20180220-116343-frh4lv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Biofluorescence makes these seahorses much easier to spot.</span>
<span class="attribution"><span class="source">Maarten De Brauwer</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We compared normal visual surveys to surveys using biofluorescence on one rare (Bargibant’s pygmy seahorse) and two common cryptic species (Largemouth triplefin and Highfin triplefin). Using biofluorescence we found twice as many pygmy seahorses, and three times the number of triplefins than with normal methods. </p>
<p>This method, which we have dubbed the “underwater biofluorescence census” makes detecting cryptic fishes easier, and counting them more accurate. While it might not detect all the animals in the way that surveys with chemicals do, it has the big benefit of not killing the species you’re counting.</p>
<p>A closer look at three large cryptic fish families (Gobies, Scorpionfishes, and Seahorses and Pipefishes) will tell you that they contain more than 2,000 species globally. The extinction risk of more than half of these species has not yet been evaluated. Many species that have been assessed are nevertheless classed as “data deficient” – a euphemistic way of saying that we don’t know enough to decide if they are endangered or not.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-you-should-never-put-a-goldfish-in-a-park-pond-or-down-the-toilet-56808">Why you should never put a goldfish in a park pond ... or down the toilet</a>
</strong>
</em>
</p>
<hr>
<p>As the majority of these cryptic species are likely to be biofluorescent, our new technique could be used to help figure out the conservation status of hundreds or even thousands of species. Our method is relatively cheap and easy to learn, and could potentially be used by citizen scientists all over the world.</p>
<p>Ultimately, the goal of scientists and conservationists alike is protecting marine ecosystems so we can have our seafood, enjoy our dives, and people can make a sustainable living off the ocean. Small cryptic fishes are essential in making all of this possible, and biofluorescent fish surveys can play a role in studying these understudied critters.</p><img src="https://counter.theconversation.com/content/86476/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Maarten De Brauwer received funding from the Society of Conservation Biology for a portion of the biofluorescence surveys in Indonesia. </span></em></p>Much of the world’s ocean is teeming with ‘cryptic’ fish species, which are small and hard to spot. But a new technique shines a light on these fish, which may in turn help to keep our seas healthy.Maarten De Brauwer, PhD-candidate in Marine Ecology, Curtin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/900182018-02-13T13:11:55Z2018-02-13T13:11:55Z‘Epic Duck Challenge’ shows drones can outdo people at surveying wildlife<figure><img src="https://images.theconversation.com/files/202530/original/file-20180119-80171-5jolfq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A drone image of a breeding colony of Greater Crested Terns. Researchers used plastic bird decoys to replicate this species in an experiment that compared different ways of counting wildlife.</span> <span class="attribution"><a class="source" href="http://www.jarrodhodgson.com.au">Jarrod Hodgson</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Ecologists are increasingly using drones to gather <a href="https://theconversation.com/flying-scarecrows-and-caribou-counters-using-drones-for-conservation-36847">data</a>. Scientists have used remotely piloted aircraft to estimate the health of <a href="https://theconversation.com/drones-help-scientists-check-the-health-of-antarctic-mosses-revealing-climate-change-clues-83817">fragile polar mosses</a>, to measure and predict the mass of <a href="https://doi.org/10.1371/journal.pone.0187465">leopard seals</a>, and even to collect <a href="https://video.nationalgeographic.com/video/news/170710-drone-collect-whale-snot-vin-spd">whale snot</a>. Drones have also been labelled as game-changers for wildlife population monitoring.</p>
<p>But once the take-off dust settles, how do we know if drones produce accurate data? Perhaps even more importantly, how do the data compare to those gathered using a traditional ground-based approach? </p>
<p>To answer these questions we created the <a href="https://twitter.com/search?q=%23epicduckchallenge&src=typd">#EpicDuckChallenge</a>, which involved deploying thousands of plastic replica ducks on an Adelaide beach, and then testing various methods of tallying them up.</p>
<p>As we report today in the journal <a href="https://doi.org/10.1111/2041-210X.12974">Methods in Ecology and Evolution</a>, drones do indeed generate accurate wildlife population data – even more accurate, in fact, than those collected the old-fashioned way.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/205420/original/file-20180208-74482-1olw6r4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/205420/original/file-20180208-74482-1olw6r4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/205420/original/file-20180208-74482-1olw6r4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=241&fit=crop&dpr=1 600w, https://images.theconversation.com/files/205420/original/file-20180208-74482-1olw6r4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=241&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/205420/original/file-20180208-74482-1olw6r4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=241&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/205420/original/file-20180208-74482-1olw6r4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=303&fit=crop&dpr=1 754w, https://images.theconversation.com/files/205420/original/file-20180208-74482-1olw6r4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=303&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/205420/original/file-20180208-74482-1olw6r4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=303&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Jarrod Hodgson standing in one of the replica colonies of seabirds constructed for the #EpicDuckChallenge.</span>
<span class="attribution"><span class="source">S. Andriolo</span></span>
</figcaption>
</figure>
<p>Assessing the accuracy of wildlife count data is hard. We can’t be sure of the true number of animals present in a group of wild animals. So, to overcome this uncertainty, we created life-sized, replica seabird colonies, each with a known number of individuals.</p>
<p>From the optimum vantage and in ideal weather conditions, experienced wildlife spotters independently counted the colonies from the ground using binoculars and telescopes. At the same time, a drone captured photographs of each colony from a range of heights. Citizen scientists then used these images to tally the number of animals they could see. </p>
<p>Counts of birds in drone-derived imagery were better than those made by wildlife observers on the ground. The drone approach was more precise and more accurate – it produced counts that were consistently closer to the true number of individuals. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/205183/original/file-20180206-88795-1fnpkuf.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/205183/original/file-20180206-88795-1fnpkuf.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/205183/original/file-20180206-88795-1fnpkuf.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=403&fit=crop&dpr=1 600w, https://images.theconversation.com/files/205183/original/file-20180206-88795-1fnpkuf.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=403&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/205183/original/file-20180206-88795-1fnpkuf.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=403&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/205183/original/file-20180206-88795-1fnpkuf.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=506&fit=crop&dpr=1 754w, https://images.theconversation.com/files/205183/original/file-20180206-88795-1fnpkuf.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=506&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/205183/original/file-20180206-88795-1fnpkuf.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=506&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Comparing the vantages: drone-derived photographs and the ground counter’s view.</span>
<span class="attribution"><span class="source">J. Hodgson</span></span>
</figcaption>
</figure>
<p>The difference between the results was not trivial. Drone-derived data were between 43% and 96% more accurate than ground counts. The variation was due to how many pixels represented each bird, which in turn is related to the height that the drone was flown and the resolution of the camera.</p>
<p>This wasn’t a surprise. The experienced ground counters did well, but the drone’s vantage point was superior. Observing photos taken from above meant the citizen scientists did not have to contend with obscured birds that often occur during ground counts. The imagery also benefited the citizen scientists as they could digitally review their counts as many times as they needed. This reduced the likelihood of both missing an individual and counting an individual more than once.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/205425/original/file-20180208-74473-8uct98.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/205425/original/file-20180208-74473-8uct98.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/205425/original/file-20180208-74473-8uct98.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/205425/original/file-20180208-74473-8uct98.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/205425/original/file-20180208-74473-8uct98.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/205425/original/file-20180208-74473-8uct98.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/205425/original/file-20180208-74473-8uct98.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/205425/original/file-20180208-74473-8uct98.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 scientists were assisted by many volunteers, without whom the #EpicDuckChallenge would not have been possible.</span>
<span class="attribution"><span class="source">J. Hodgson</span></span>
</figcaption>
</figure>
<p>However, even though it proved to be more accurate, making manual digital counts is still tedious and time-consuming. To address this, we developed a computer algorithm in the hope that it could further improve efficiency without diminishing data quality. And it did. </p>
<p>We delineated a proportion of birds in each colony to train the algorithm to recognise how the animal of interest appeared in the imagery. We found that using 10% training data was sufficient to produce a colony count that was comparable to that of a human reviewing the entire scene. </p>
<p>This computerisation can reduce the time needed to process data, providing the opportunity to cut the costs and resources needed to survey wildlife populations. When combined with the efficiencies drones provide for surveying sites that are hard to access on foot, these savings may be considerable. </p>
<h2>Using drone monitoring in the field</h2>
<p>Our results have important implications for a range of species. We think they are especially relevant to <a href="https://doi.org/10.1038/srep22574">aggregating birds</a>, including seabirds like albatrosses, surface nesting penguins and frigatebirds, as well as colonial nesting waterbirds like pelicans. </p>
<p>Other types of animals that are easily seen from above, including <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3377645/">hauled-out seals</a> and dugongs, are highly suited to drone monitoring. The nests or tracks of animals, such as orangutans and turtles, can also be used to infer presence. </p>
<p>Additional experiments will be useful to assess the ability of drones to survey animals that prefer to stay hidden and those within complex habitats. Such assessments are of interest to us, and researchers around the globe, with current investigations focused on wildlife such as arboreal mammals and cetaceans. </p>
<p>We are still <a href="https://theconversation.com/a-guide-to-using-drones-to-study-wildlife-first-do-no-harm-57069">learning about how wildlife react to the presence of drones</a>, and more research is required to quantify these responses in a range of species and environments. The results will help to refine and improve <a href="https://doi.org/10.1016/j.cub.2016.04.001">drone monitoring protocols</a> so that drones have minimal impact on wildlife. This is particularly important for species that are prone to disturbance, and where close proximity is not possible or desirable.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-drones-can-help-fight-the-war-on-shark-attacks-71633">How drones can help fight the war on shark attacks</a>
</strong>
</em>
</p>
<hr>
<p>The world is rapidly changing, with many <a href="https://doi.org/10.1126/sciadv.1400253">negative outcomes for wildlife</a>. Technology like drones can help scientists and managers gather data fast enough to enable timely assessment of the implications of these changes. </p>
<p>When monitoring wildlife, increasing the accuracy and precision of animal surveys gives us more confidence in our population estimates. This provides a stronger evidence base on which to make management decisions or policy changes. For species and ecosystems threatened with extinction or irreparable damage, such speedy action could be a literal lifeline.</p><img src="https://counter.theconversation.com/content/90018/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jarrod Hodgson is supported by an Australian Government Research Training Program
Scholarship.</span></em></p><p class="fine-print"><em><span>Aleks Terauds receives funding from the Australian Antarctic Program</span></em></p><p class="fine-print"><em><span>Lian Pin Koh receives funding from Australian Research Council.</span></em></p>A few thousand fake ducks, a group of experienced wildlife spotters and a drone have proven the usefulness and accuracy of drones for wildlife monitoring.Jarrod Hodgson, PhD Candidate, University of AdelaideAleks Terauds, Senior Research Scientist / Section Head, Australian Antarctic DivisionLian Pin Koh, Professor, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.