tag:theconversation.com,2011:/id/topics/habitat-5024/articlesHabitat – The Conversation2024-03-20T22:41:06Ztag:theconversation.com,2011:article/2246822024-03-20T22:41:06Z2024-03-20T22:41:06ZHow do halibut migrate? Clues are in their ear bones<figure><img src="https://images.theconversation.com/files/578657/original/file-20240220-18-5yndy5.jpg?ixlib=rb-1.1.0&rect=24%2C18%2C3953%2C2999&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The habitats used throughout the halibut's life and the movements between them are difficult to characterize.</span> <span class="attribution"><span class="source">(Charlotte Gauthier)</span>, <span class="license">Fourni par l'auteur</span></span></figcaption></figure><p>Rising temperatures, changes in major currents, <a href="https://theconversation.com/why-the-st-lawrence-estuary-is-running-out-of-breath-184626">oxygen depletion at great depths</a>: the Gulf of St. Lawrence has undergone major changes in its environmental conditions in recent decades. That has put many species in danger and, as a consequence, made them more sensitive to the effects of fishing.</p>
<p>However, these changes are benefiting other species such as Atlantic halibut, which is beating records for its abundance and is presently seeing the highest stock in the Gulf of St. Lawrence in <a href="https://waves-vagues.dfo-mpo.gc.ca/library-bibliotheque/41206708.pdf">the last 60 years</a>.</p>
<p>As a biology researcher, I’d like to shed some light on some of the mysteries that still surround this unusual species.</p>
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<img alt="" src="https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em>This article is part of our series, <a href="https://theconversation.com/ca-fr/topics/fleuve-saint-laurent-116908">The St. Lawrence River: In depth</a>.
Don’t miss new articles on this mythical river of remarkable beauty. Our experts look at its fauna, flora and history, and the issues it faces. This series is brought to you by <a href="https://theconversation.com/ca-fr">La Conversation</a>.</em></p>
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<h2>Atlantic halibut: champion of the Gulf of St. Lawrence</h2>
<p>Atlantic halibut is a flatfish that lives at the bottom of the estuary and gulf of the St. Lawrence. It is prized for its fine, firm white flesh, which is highly appreciated by consumers.</p>
<p>Halibut can grow to impressive sizes of <a href="https://www.tandfonline.com/doi/full/10.1080/23308249.2021.1948502">more than two metres</a>. Because of the quality of its flesh and its popularity on dinner plates, it is currently the most commercially valuable fish in the Gulf of St. Lawrence.</p>
<p>But this has not always been the case. In the 1950s, the adult, harvestable portion of halibut populations, known as the stock, <a href="https://academic.oup.com/icesjms/article/73/4/1104/2458915?login=false">suffered a major decline due to overfishing</a>.</p>
<p>If we want to continue to exploit this resource over the long term, we must not repeat the same mistakes we made in the past. To avoid these mistakes, it is vital to have a good understanding of the life cycle of halibut and the effects that fishing can have on the stock. So far, this has not been done to the fullest.</p>
<h2>The challenges for sustainable fishing</h2>
<p>The basic biology of Atlantic halibut is fairly well known. However, both the habitats they use throughout their lives and their movement between these places are more difficult to characterize.</p>
<p><a href="https://academic.oup.com/icesjms/article/77/7-8/2890/5923787?login=false">Recent studies</a> have placed satellite tags on halibut to record data on the depth and temperature of the water in which they are found, making it possible to accurately calculate their movement. By using this method, the researchers were able to identify the trajectories of adult halibut over a one-year period and discover that they reproduce in winter in the deep channels of the Gulf.</p>
<p>In the halibut’s different annual trajectories, the researchers observed that, in summer, some remain in the deep channels while others migrate to shallower areas.</p>
<p>Even with this new information, a number of questions remain, specifically about the youngest life stages, which are caught only anecdotally in the Gulf. Satellite tags also provide accurate information, but only over a one-year period, which doesn’t tell the whole story for a fish that can live up to 50 years.</p>
<p>With this in mind, the use of a new tool to study the entire life of fish becomes highly relevant.</p>
<h2>Ear bones to the rescue</h2>
<p>All bony fish have small calcareous structures in their inner ear called otoliths, or ear bones, which perform balance and hearing functions.</p>
<p>Otoliths develop at the very beginning of a fish’s life and grow at the same rate as the fish. Otoliths form annual growth rings that are comparable to those visible in tree trunks.</p>
<p>To grow, otoliths accumulate chemical elements that are found in the environment in which the fish swim. So, when the fish moves, the chemical elements accumulated in the otoliths will be different from one place to another. Each location is characterized by a unique combination of different concentrations of chemical elements. This is known as an elemental fingerprint. Identifying these fingerprints can provide us with crucial information about the movement of fish in different places throughout their lives.</p>
<p>I used this method of characterizing the chemical elements in otoliths to study the migratory patterns of Atlantic halibut in the Gulf of St. Lawrence.</p>
<h2>A wide range of migratory strategies</h2>
<p>To find out what concentrations of a chemical element correspond to the place where the fish was caught, we use the fingerprint of the otolith margin, i.e. the material at the end of the outermost ring of the otolith, which was accumulated last.</p>
<p>The concentrations of the elements found there are considered to be characteristic of the place where the fish was caught. By analyzing the margins of nearly 200 halibut otoliths from all over the Gulf, I was able to distinguish two basic fingerprints: one representative of surface waters (less than 100 metres deep) and one characteristic of deeper waters (more than 100 metres deep).</p>
<p>Once these fingerprints had been identified, I observed the concentration of chemical elements throughout the life of the fish so that I could associate each moment of life with either the surface water fingerprint or the deep-water fingerprint.</p>
<p>By separating the life of each individual into time spent in surface and deep waters, I was able to identify recurring patterns and group them into three different migratory strategies: residents, annual migrants and irregular migrants.</p>
<p>In this way, I was able to observe that halibut caught in the southern part of the Gulf were mainly annual migrants, and therefore undertake migrations between deep and shallow waters every year. However, in the northern part of the Gulf the majority are residents. Residents are fish that may have migrated early in their lives, but have settled permanently in deep waters before reaching maturity. Irregular migrants, on the other hand, show migrations on a more sporadic frequency, and are found in similar proportions throughout the study area.</p>
<h2>On the right track to optimal management</h2>
<p>My study is the first to offer a global view of the movements made by halibut over their entire lifetime.</p>
<p>This new information provides a better understanding of the structure of the stock and the diversity of migratory strategies that can be found within it.</p>
<p>Given that these strategies are distributed differently in different areas of the Gulf, we can ensure that we do not disproportionately target halibut using the same migratory strategy and avoid overfishing a single component of the stock.</p>
<p>In this way, it is possible to conserve this diversity, which helps the stock’s resilience in the face of the various changes that can occur.</p><img src="https://counter.theconversation.com/content/224682/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Charlotte Gauthier has received funding from the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Fondation de l'Université du Québec à Chicoutimi.
</span></em></p>Atlantic halibut are making a strong comeback in the Gulf of St. Lawrence. But how do we know where the fish move throughout their lives?Charlotte Gauthier, Étudiante au doctorat, Université du Québec à Chicoutimi (UQAC)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2242842024-03-08T16:21:36Z2024-03-08T16:21:36ZRestored coral reefs can grow as fast as healthy reefs after just four years – new study<p>The coral reefs of south Sulawesi are some of the most diverse, colourful and vibrant in the world. At least, they used to be, until they were <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/rec.12866">decimated by dynamite fishing</a> in the 1990s. </p>
<p>As part of a team of coral reef ecologists based in Indonesia and the UK, we study the reefs around Pulau Bontosua, a small Indonesian island in south Sulawesi. Thirty years on, what were once large areas of thriving coral are now degraded sites are still devoid of colour, fish and other marine life. Broken skeletons of dead corals roll around on the seabed, crushing and killing any new coral larvae that try to settle and preventing the reefs from recovering naturally. </p>
<p>In many places around the world, damage like this might be described as irreparable. But at Pulau Bontosua, the story is different. Here, efforts by the <a href="https://www.buildingcoral.com/">Mars coral restoration programme</a> have brought back the coral and important ecosystem functions, as outlined by our new study, <a href="https://doi.org/10.1016/j.cub.2024.02.009">published in Current Biology</a>. We found that within just four years, restored reefs grow at the same rate as nearby healthy reefs. </p>
<p>The Mars coral restoration programme is one of the world’s largest restoration projects and has collaborated with local communities for more than a decade. Healthy coral fragments are attached to hexagonal, sand-covered steel frames called “reef stars”. These reef stars are installed on damaged reefs, where they stabilise the loose rubble, support growth of new coral and provide habitat for reef animals to move in.</p>
<h2>Speedy recovery</h2>
<p>The transplanted corals grow remarkably quickly. Within a year, fragments have developed into proper colonies. After two years, they interlock branches with their neighbours. After just four years, they completely overgrow the reef star structures and restoration sites are barely distinguishable from nearby healthy reefs.</p>
<p>The combined growth of many corals generates a complex limestone (calcium carbonate) framework. This provides habitat for marine life and protects nearby shorelines from storm damage by <a href="https://theconversation.com/coral-reefs-work-as-natures-sea-walls-it-pays-to-look-after-them-26655">absorbing up to 97% of coastal wave energy</a>. </p>
<p>We measured the overall growth of the reef framework by calculating its <a href="https://www.exeter.ac.uk/research/projects/geography/reefbudget/">carbonate budget</a>. That’s the balance between limestone production (by calcifying corals and coralline algae) and erosion (by grazing sea urchins and fishes, for example). A healthy reef produces up to 20kg reef structure per square metre per year, while a degraded reef is shrinking rather than growing, as erosion exceeds limestone production. Therefore, overall reef growth gives an indication of reef health.</p>
<p>At Pulau Bontosua, our survey data shows that in the years following restoration, coral cover, coral colony sizes and carbonate production rates tripled. Within four years, restored reefs were growing at the same speed as healthy reefs, and thereby provided the same important ecosystem functions.</p>
<p>This success is encouraging, but challenges still remain. The corals used to construct these restored reefs are predominantly branching coral types, chosen by the restoration team because they are easier to attach to the reef stars. This means that restored reefs have a lower diversity of coral types than healthy reefs, which host an abundance of boulder-like and encrusting corals as well as branching types. </p>
<p>These structural differences may affect the species of marine life that inhabit the reef. Branching corals are also notoriously sensitive to <a href="https://www.worldwildlife.org/pages/everything-you-need-to-know-about-coral-bleaching-and-how-we-can-stop-it">bleaching</a>, which happens when warmer water temperatures cause stress to corals and turn them white. Differences in the types of coral making up the reef ecosystem may therefore affect the reef’s ability to survive future heat waves. </p>
<h2>A warming world</h2>
<p>Marine heat waves are becoming <a href="https://theconversation.com/the-great-barrier-reef-has-been-bleaching-for-at-least-400-years-but-its-getting-worse-101691">more frequent and severe</a> and pose a huge threat to coral reefs and restoration efforts worldwide. Recently, thousands of <a href="https://theconversation.com/the-heroic-effort-to-save-floridas-coral-reef-from-extreme-ocean-heat-as-corals-bleach-across-the-caribbean-210974">nursery corals had to be rescued</a> when water temperatures spiked in the Florida Keys.</p>
<p>It’s imperative that coral reef restoration strategies include plans for warming waters. In some cases, efforts can be prioritised in areas where transplanted corals are less likely to encounter lethal conditions in the near future. In other cases, projects can enhance coral heat tolerance through <a href="https://theconversation.com/the-great-barrier-reef-can-repair-itself-with-a-little-help-from-science-85182">assisted evolution</a>. </p>
<p>There is some evidence that coral heat tolerance can also <a href="https://theconversation.com/remote-pacific-coral-reef-shows-at-least-some-ability-to-cope-with-ocean-warming-new-study-211852">increase naturally</a>. Whether this coral adaptation can keep pace with ocean warming will depend on global action to cut carbon emissions.</p>
<p>Outcomes of any reef restoration project will depend on environmental conditions, natural coral larvae supply, restoration techniques and the effort invested in maintaining the project. This Indonesian project shows that when conditions are right and efforts are well placed, success is possible. Hopefully, this inspires further global efforts to restore functioning coral reefs and to recreate a climate in which they can thrive.</p>
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<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p class="fine-print"><em><span>Ines Lange receives funding from the Bertarelli Program in Marine Science. Logistical research support for this study was provided by Mars Sustainable Solutions.</span></em></p><p class="fine-print"><em><span>Tim Lamont receives funding from the Royal Commission for the Exhibition of 1851, and the Fisheries Society of the British Isles. </span></em></p><p class="fine-print"><em><span>Tries Blandine Razak does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Artificial reef stars have been added to damaged coral reefs in Sulawesi, Indonesia. A new study shows that within just four years, restored reefs are thriving as much as healthy reefs.Ines Lange, Senior Research Fellow in Coral Reef Ecology, University of ExeterTim Lamont, Research Fellow, Lancaster UniversityTries Blandine Razak, Researcher, IPB UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2207602024-01-18T13:28:52Z2024-01-18T13:28:52ZNot all underwater reefs are made of coral − the US has created artificial reefs from sunken ships, radio towers, boxcars and even voting machines<figure><img src="https://images.theconversation.com/files/569704/original/file-20240116-27-b90elk.jpg?ixlib=rb-1.1.0&rect=8%2C0%2C5682%2C3788&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The bow of the U.S. Coast Guard cutter Duane, a decommissioned ship deliberately sunk off Florida to serve as an artificial reef.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/bow-of-uscg-duane-royalty-free-image/492717259">Stephen Frink via Getty Images</a></span></figcaption></figure><p>When people hear about underwater reefs, they usually picture colorful gardens created from coral. But some reefs are anchored to much more unusual foundations. </p>
<p>For more than a century, people have placed a wide assortment of objects on the seafloor off the U.S. coast to provide habitat for marine life and recreational opportunities for fishing and diving. Artificial reefs have been created from decommissioned ships, chicken transport cages, concrete pipes, rail cars and more.</p>
<p>We study how ocean-dwelling fish <a href="https://scholar.google.com/citations?user=wZ-kv2AAAAAJ&hl=en">use artificial reefs</a> in the <a href="https://scholar.google.com/citations?user=WF8vzA4AAAAJ">U.S. and beyond</a>. Through our research, we have learned that artificial reefs can be hot spots for large predatory fish such as <a href="https://doi.org/10.1111/faf.12548">groupers</a> and <a href="https://doi.org/10.1371/journal.pone.0237374">jacks</a>. They also can serve as <a href="https://doi.org/10.1038/s42003-019-0398-2">stepping stones</a> for reef fish expanding their range northward with warming water temperatures and as <a href="https://doi.org/10.1002/ecy.2687">rest stops</a> for sharks. </p>
<p>Artificial reefs can be <a href="https://doi.org/10.1002/ecs2.3924">strategically designed and placed</a> to optimize fish habitat. But although they provide valuable ecological services, no one has inventoried how many of these structures exist in U.S. waters or how much seafloor they occupy.</p>
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<a href="https://images.theconversation.com/files/569699/original/file-20240116-25-xly63u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Fish swim through a sunken ship doorway rimmed with coral as a scuba diver hovers nearby." src="https://images.theconversation.com/files/569699/original/file-20240116-25-xly63u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/569699/original/file-20240116-25-xly63u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/569699/original/file-20240116-25-xly63u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/569699/original/file-20240116-25-xly63u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/569699/original/file-20240116-25-xly63u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/569699/original/file-20240116-25-xly63u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/569699/original/file-20240116-25-xly63u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">A diver at the U.S. Coast Guard cutter Duane, which was decommissioned in 1985 and intentionally sunk in 1987 off Key Largo, Fla., to create reef habitat.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/diver-on-shipwreck-royalty-free-image/109010339">Stephen Frink/The Image Bank via Getty Images</a></span>
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<p>To help fill this knowledge gap, we led a team of scientists and artificial reef directors from the 17 U.S. states with artificial reef-building programs in the first national calculation of artificial reef extent. Our <a href="https://www.nature.com/articles/s41893-023-01258-7">new study</a> shows that these reefs cover a total of about 7 square miles (19 square kilometers) of U.S. seafloor – an area equivalent to 3,600 football fields. We also describe the diversity of objects used to create reefs, as well as patterns in artificial reef creation over time.</p>
<h2>Creating modern artificial reefs</h2>
<p>Modern reefing is different from dumping trash into the water and is <a href="https://media.fisheries.noaa.gov/dam-migration/noaa_artificial_reef_guidelines.pdf">regulated at the federal and state levels</a>. A rigorous permitting and approval process ensures that the proposed objects or materials are appropriate to deploy in the ocean. </p>
<p>For example, decommissioned ships are thoroughly <a href="https://www.epa.gov/ocean-dumping/vessel-reef-projects">cleaned and drained of fuel and other polluting substances</a> prior to sinking to minimize environmental risks. Some materials that were once used to create artificial reefs, such as rubber, fiberglass, wood and plastic, are now prohibited because they may move from their placed location, damaging nearby habitat, or deteriorate quickly in salt water. </p>
<p>Reefed objects can be sunk only in predesignated areas of the U.S. seafloor. These zones, which are usually sandy sea bottom, total about 2,200 square miles (5,800 square kilometers) – roughly the area of Delaware.</p>
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<figcaption><span class="caption">Seven months after the Texas Parks and Wildlife Dept.’s artificial reef program sank the Kraken, a decommissioned 371-foot cargo ship, divers found it heavily colonized by ocean life.</span></figcaption>
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<p>Each zone can support the creation of many individual reefs over multiple decades. Within a given zone, reefed objects are usually placed away from one another, separated by large swaths of sand. This maximizes the amount of sand habitat, where some reef fish forage.</p>
<p>The extent of artificial reefs in these zones has increased by about 2,000% over the past 50 years. Since 2010, however, artificial reef extent has grown only 12%. This is likely because of challenges in acquiring and sinking acceptable reef materials. It could also reflect a push toward <a href="https://theconversation.com/3d-printing-coral-reefs-can-create-new-habitat-but-it-doesnt-tackle-human-destruction-103927">developing structures</a> specifically for use as artificial reefs. </p>
<h2>Planes, trains and automobiles</h2>
<p>For our study, we gathered records of intentional reefings dating back to 1899 and occurring off artificial all U.S. coastal states, except for six without artificial ocean reef programs: Maine, New Hampshire, Connecticut, Oregon, Washington and Alaska.</p>
<p>For some of these events, especially in recent decades, there were detailed records of the sizes and quantities of sunken objects or seafloor maps from which we could derive these measurements. These reefs were easy to quantify. </p>
<p>Other records, including some from the early 20th century, had scant detail. For these, we developed an approach to estimate how much seafloor the reefs covered, based on similar deployments with better records.</p>
<p>Our study found a vast assortment of reefed objects on the U.S. seafloor. They included decommissioned tugboats, fishing vessels, barges, ferries and military vessels. Reefs have also been created from rail boxcars, aircraft, vehicles, chicken transport cages, voting machines, missile platforms, concrete pipes, radio towers, tires, limestone rocks and objects purposely designed as artificial reefs.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/569701/original/file-20240116-19-2hqu7p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A boat with a crane lowers pyramid-shaped structures into the water." src="https://images.theconversation.com/files/569701/original/file-20240116-19-2hqu7p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/569701/original/file-20240116-19-2hqu7p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/569701/original/file-20240116-19-2hqu7p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/569701/original/file-20240116-19-2hqu7p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/569701/original/file-20240116-19-2hqu7p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/569701/original/file-20240116-19-2hqu7p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/569701/original/file-20240116-19-2hqu7p.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 Florida Fish and Wildlife Commission deploys artificial reef modules off the coast of Mexico Beach on April 6, 2013.</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/eh6fXS">Florida Fish and Wildlife Commission/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Objects that occupy the largest amount of seafloor include limestone rocks, large concrete modules designed specifically for reefing, metal rigs and towers and long, narrow concrete pieces repurposed from their previous uses, such as culverts or bridges.</p>
<h2>Potential impacts</h2>
<p>After a reef is created, fish can appear within minutes or hours. The sequence of fish arrival sometimes <a href="https://doi.org/10.1016/j.ecoleng.2018.09.012">follows a pattern</a>. Transient fish such as jacks and barracuda come first, followed by bottom-dwelling fish such as grouper and smaller reef fish. With time, plants and animals grow on the hard surfaces of the artificial reef, helping to provide food and sanctuary for fish.</p>
<p>However, these reefs can also cause ecological harm. Invasive species, such as plants and other animals that grow on hard structures, can use artificial reefs to <a href="https://doi.org/10.1371/journal.pone.0038124">spread to new places</a>. </p>
<p>Artificial reefs also may attract fish away from nearby natural reefs. Since constructed reefs are often in prime recreational fishing locations, this could lead to higher catches of those species. </p>
<p>Another risk is that if artificial reefs are improperly placed or secured on the sea floor, they can shift into unintended areas and harm sensitive habitats, particularly in the aftermath of storms. For example, Florida <a href="https://www.theguardian.com/us-news/2015/may/22/florida-retrieving-700000-tires-after-failed-bid-to-create-artifical-reef">sank 1 million to 2 million tires offshore</a> in the 1970s in an effort to create artificial reefs, but sea life didn’t colonize them as intended. Now the tires are washing around and smothering coral.</p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/reel/CxvnpSdOnsr/?utm_source=ig_web_copy_link","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<h2>Learning from artificial reefs</h2>
<p>Monitoring how fish and other species use artificial reefs, especially compared with naturally occurring reefs, will be key for understanding benefits and risks from these structures. As <a href="https://theconversation.com/artificial-coral-reefs-showing-early-signs-they-can-mimic-real-reefs-killed-by-climate-change-new-research-215011">climate change</a> continues to alter ocean ecosystems, we see opportunities to learn which types of artificial reefs are best suited for enhancing habitat for particular sorts of fish. </p>
<p>For example, we know that large predators that dwell in open water, such as jacks, barracuda and sharks, tend to prefer <a href="https://doi.org/10.1371/journal.pone.0237374">taller artificial reefs over shorter ones</a>. This is similar to insights from oil rigs, showing that these vertical and complex structures are <a href="https://doi.org/10.1073/pnas.1411477111">valuable fish habitat</a>. More than 500 decommissioned oil rigs <a href="https://www.bsee.gov/what-we-do/environmental-compliance/environmental-programs/rigs-to-reefs">have been converted to reefs</a>. Our calculation included only those that are managed by state artificial reef programs. </p>
<p>Other structures in the water, such as <a href="https://theconversation.com/as-the-us-begins-to-build-offshore-wind-farms-scientists-say-many-questions-remain-about-impacts-on-the-oceans-and-marine-life-216330">offshore wind turbine foundations</a>, will <a href="https://youtu.be/0SBxDWuE1vY">likely form habitat for sea life</a> similarly to artificial reefs. Insights about what types of structures different fish prefer may help guide the design or location of offshore wind farms.</p>
<p>Humans rely on the ocean for many benefits, including food, commerce, energy and a stable climate. Measuring artificial reefs’ footprint is a first step toward understanding their effects, both good and bad, on ocean wildlife and human uses of the ocean.</p>
<p><em><a href="https://www.nature.org/en-us/about-us/where-we-work/united-states/virginia/stories-in-virginia/our-staff/">Brendan Runde</a>, a marine scientist at The Nature Conservancy, contributed to this article.</em></p><img src="https://counter.theconversation.com/content/220760/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 organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Artificial reefs are structures that humans put in place underwater that create habitat for sea life. A new study shows for the first time how much of the US ocean floor they cover.Avery Paxton, Research Marine Biologist, National Oceanic and Atmospheric AdministrationD'amy Steward, Master's Student in Biology, University of GuamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2189022024-01-11T13:25:55Z2024-01-11T13:25:55ZTo protect endangered sharks and rays, scientists are mapping these species’ most important locations<figure><img src="https://images.theconversation.com/files/565884/original/file-20231214-27-kjjzka.jpg?ixlib=rb-1.1.0&rect=60%2C0%2C6720%2C4426&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A tiger shark swims among surgeonfish off Fuvahmulah Atoll, Maldives, in the Indian Ocean.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/tiger-shark-with-shoal-of-fish-surgeonfishes-indian-royalty-free-image/1262279323">imageBROKER/Norbert Probst via Getty Images</a></span></figcaption></figure><p>All of the saltwater bodies on Earth make up <a href="https://oceanservice.noaa.gov/facts/howmanyoceans.html">one big ocean</a>. But within it, there is infinite variety – just ask any scuba diver. Some spots have more coral, more sea turtles, more fish, more life. </p>
<p>“I’ve been diving in many places around the world, and there are few locations like the <a href="https://visitfuvahmulah.mv/discover-fuvahmulah/">Fuvahmulah Atoll</a> in the Maldives,” Amanda Batlle-Morera, a research assistant with the <a href="https://sharkrayareas.org/">Important Shark and Ray Areas project</a>, told me. “You can observe tiger sharks, thresher sharks, scalloped hammerheads, oceanic manta rays and more, without throwing out bait to attract them.” </p>
<p>Identifying areas like Fuvahmulah that are especially important to certain species is a <a href="https://www.fws.gov/sites/default/files/documents/critical-habitat-fact-sheet.pdf">long-standing strategy</a> for protecting threatened land animals, birds and marine mammals, such as whales and dolphins. Now our team of marine conservation scientists at the <a href="https://sharkrayareas.org/">Important Shark and Ray Areas project</a> is using it to help protect sharks and their relatives. </p>
<p>I am a <a href="https://scholar.google.com/citations?user=xb7noGAAAAAJ&hl=en">marine conservation biologist</a> and the project’s communications officer. This initiative is working to identify locations that are critical for sharks and rays, so that these zones can be flagged for future protection or fisheries management measures. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/0mPBvhGvZLI?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Divers get close views of tiger sharks at Fuvahmulah, an offshore island in the southern Maldives. Six threatened shark species and one threatened ray species appear regularly in the area.</span></figcaption>
</figure>
<h2>Where the sharks are</h2>
<p>Sharks and their relatives are some of the most imperiled animals on Earth: More than one-third of all known species are <a href="https://doi.org/10.1016/j.cub.2021.08.062">threatened with extinction</a>. Many of these animals play vital roles in their ecosystems. Losing marine predators <a href="https://doi.org/10.1016/j.tree.2008.01.003">can destabilize entire food webs</a> and the ecosystems that these food webs depend on.</p>
<p>In recent years, the management of sharks and their relatives, rays and chimaeras, has largely focused on curbing the impacts of fisheries and trade on these species. But their populations <a href="https://doi.org/10.1016/j.cub.2021.08.062">are still declining rapidly</a>, so new strategies are needed. </p>
<p>To effectively protect these important and threatened animals, my colleagues and I believe it is vital to identify and protect parts of the ocean, plus some freshwater habitats, that are especially significant for their lives. Some areas, for example, are important migratory pathways, or feeding or mating grounds, or places to lay eggs. </p>
<p>Our team has created a <a href="https://doi.org/10.3389/fmars.2022.968853">list of technical criteria</a> so that zones around the world can be examined and potentially designated as Important Shark and Ray Areas. We modeled these criteria on similar approaches that are already in use, such as <a href="https://doi.org/10.1641/0006-3568(2004)054%5B1110:KBAASC%5D2.0.CO;2">important marine mammal areas</a>, which we adapted to the specific needs and biology of sharks and their relatives. </p>
<p>We are now hosting a series of 13 regional workshops around the world and inviting local experts to nominate preliminary areas of interest for evaluation by our team and an independent expert review panel. So far, we’ve completed three workshops, one focusing on the Central and South American Pacific, another on the Mediterranean and Black seas, and the third on the Western Indian Ocean, with a workshop for Asia planned for early 2024. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/568049/original/file-20240105-14-7s4g8o.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A world map shows zones that scientists have identified as Important Shark and Ray Areas in the Pacific and Indian oceans and the Mediterranean Sea." src="https://images.theconversation.com/files/568049/original/file-20240105-14-7s4g8o.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/568049/original/file-20240105-14-7s4g8o.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=308&fit=crop&dpr=1 600w, https://images.theconversation.com/files/568049/original/file-20240105-14-7s4g8o.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=308&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/568049/original/file-20240105-14-7s4g8o.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=308&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/568049/original/file-20240105-14-7s4g8o.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=387&fit=crop&dpr=1 754w, https://images.theconversation.com/files/568049/original/file-20240105-14-7s4g8o.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=387&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/568049/original/file-20240105-14-7s4g8o.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=387&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 current version of the online atlas of Important Shark and Ray Areas. The atlas is organized by region, showing which parts of the world’s oceans and coasts have been assessed.</span>
<span class="attribution"><a class="source" href="https://sharkrayareas.org/">Important Shark and Ray Areas initiative</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>After the workshops and expert reviews, each finalized Important Shark and Ray Area will be added to our e-atlas, which <a href="https://sharkrayareas.org/e-atlas/">can be viewed online</a>. Each region’s Important Shark and Ray Areas are published in a formal compendium, and the whole global process will be repeated every 10 years. This cycle will allow us to consider changes to areas that have already been mapped, such as new fishery policies or impacts from climate change, and to take into account new research that can help us identify new areas. </p>
<h2>Informing conservation policies</h2>
<p>We recently published our <a href="https://sharkrayareas.org/download/mediterranean-and-black-seas-regional-compendium-of-important-shark-and-ray-areas/">Mediterranean and Black seas region compendium</a>, which reflects input from over 180 experts from around the region. It identifies 65 Important Shark and Ray Areas that range widely in size and habitat type. Our <a href="https://sharkrayareas.org/download/western-indian-ocean-regional-compendium-of-important-shark-and-ray-areas/">western Indian Ocean compendium</a> includes over 125 areas. </p>
<p>These zones are important for species like the critically endangered <a href="https://www.fisheries.noaa.gov/species/blackchin-guitarfish">blackchin guitarfish</a> (<em>Glaucostegus cemiculus</em>), as well as heavily fished shark species like the <a href="https://www.sharks.org/smoothhound-mustelus-mustelus">common smoothhound shark</a> (<em>Mustelus mustelus</em>). </p>
<p>Some of these areas, such as <a href="https://sharkrayareas.org/portfolio-item/benidorm-island-isra/">Benidorm Island</a> off Spain’s Mediterranean coast, are in shallow coastal zones. Others, like the <a href="https://sharkrayareas.org/wp-content/uploads/isra-factsheets/12CentralSouthPacific/Cocos-Galapagos-Swimway-12CentralSouthPacific.pdf">Cocos-Galapagos Swimway</a> off Costa Rica and Ecuador, reach into deep ocean waters. </p>
<p>The smallest area identified so far, Israel’s <a href="https://sharkrayareas.org/wp-content/uploads/isra-factsheets/03MedBlackSeas/Palmahim-Brine-Pools-03MedBlackSeas.pdf">Palmahim brine pools</a> in the southeast Mediterranean, measures just 0.03 square miles (0.09 square kilometers) – about half the size of New York City’s Grand Central station. <a href="https://eol.org/pages/46560072">Blackmouth catsharks</a>
(<em>Galeus melastomus</em>) breed and lay eggs there, and threatened <a href="https://eol.org/pages/46560287">angular rough sharks</a> (<em>Oxynotus centrina</em>) feed there, including on blackmouth catshark eggs. </p>
<p>The largest area is the <a href="https://sharkrayareas.org/wp-content/uploads/isra-factsheets/03MedBlackSeas/Strait-of-Sicily-and-Tunisian-Plateau-03MedBlackSeas.pdf">Strait of Sicily and Tunisian Plateau</a>, which extends over 77,000 square miles (200,000 square kilometers) – about the size of Great Britain – in the Mediterranean between Sicily, Malta, western Libya and Tunisia. This zone supports at least 32 species of sharks, rays and chimaeras, including many that are at risk of extinction, in habitats ranging from shallow seagrass beds to deep ocean trenches.</p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CsHnxebvcsp/?utm_source=ig_web_copy_link\u0026igsh=MzRlODBiNWFlZA==","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<p>Identifying a location as an Important Shark and Ray Area does not mean it will automatically be protected. Our goal is to inform countries’ existing spatial planning and fisheries management processes and other conservation planning. Eventually, these zones may be incorporated into <a href="https://oceanexplorer.noaa.gov/facts/mpas.html">marine protected areas</a> or other types of ocean preserves.</p>
<p>Sharks and their relatives need human help to survive and maintain their important biological roles in the ocean. Through the Important Shark and Ray Areas project, hundreds of scientists and other experts are helping to identify special places for these species that we believe need some extra attention.</p>
<p><em>Dr. Rima Jabado, chair of the IUCN Species Survival Commission Shark Specialist Group, contributed to this article.</em></p><img src="https://counter.theconversation.com/content/218902/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Shiffman 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>A new initiative is pinpointing areas in the world’s oceans that are key habitats for sharks and their relatives, so that governments can consider protecting these areas.David Shiffman, Faculty Research Associate in Marine Biology, Arizona State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2188992023-12-19T13:16:50Z2023-12-19T13:16:50ZWild ‘super pigs’ from Canada could become a new front in the war on feral hogs<figure><img src="https://images.theconversation.com/files/566082/original/file-20231215-23-irn2uo.jpg?ixlib=rb-1.1.0&rect=8%2C4%2C2986%2C1958&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Feral hogs' long snouts and tusks allow them to rip and root their way across the landscape in search of food. </span> <span class="attribution"><a class="source" href="https://flic.kr/p/ehmMiS">USDA/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>They go by many names – pigs, hogs, swine, razorbacks – but whatever you call them, <a href="https://www.invasivespeciesinfo.gov/profile/wild-boar">wild pigs</a> (<em>Sus scrofa</em>) are one of the <a href="https://www.washingtonpost.com/science/2019/08/06/think-feral-hogs-is-joke-millions-more-are-rampaging-across-us/">most damaging invasive species</a> in North America. They cause millions of dollars in crop damage yearly and harbor dozens of pathogens that threaten humans and pets, as well as meat production systems.</p>
<p>Although wild pigs have been <a href="https://www.aphis.usda.gov/aphis/ourfocus/wildlifedamage/operational-activities/feral-swine/sa-fs-history">present in North America for centuries</a>, their populations have rapidly expanded over the past several decades. Recent studies estimate that since the 1980s the wild pig population in the United States has <a href="https://doi.org/10.1007/s10530-019-01983-1">nearly tripled</a> and <a href="https://doi.org/10.1002/wsb.808">expanded from 18 to 35 states</a>. More recently, they have <a href="https://www.cbc.ca/news/canada/british-columbia/invasive-pigs-canada-1.5136431">spread rapidly across Canada</a>, and these populations are <a href="https://apnews.com/article/wild-pigs-feral-swine-canada-minnesota-border-e59a542efb3c64d5f4b136fc137b7665">threatening to invade the U.S. from the north</a>.</p>
<p>The wild pigs in Canada are unique because they were originally crossbred by humans to be larger and more cold-hardy than their feral cousins to the south. This suite of traits has earned them the name “super pigs” for good reason. Adults can reach weights exceeding 500 pounds, which is twice the size of the largest wild pigs sampled across many U.S. sites in <a href="http://dx.doi.ORG/10.1002/ece3.9853">a 2022 study</a>. </p>
<p>As a <a href="https://www.researchgate.net/profile/Marcus_Lashley">wildlife ecologist</a>, I study how wild pigs alter their surroundings and affect other wildlife species. <a href="https://www.doi.gov/invasivespecies/early-detection-and-rapid-response">Early detection and rapid response</a> is of utmost importance in eradicating an invasive species, because invasions are more manageable when populations are small and geographically restricted. This is especially true for species like wild pigs that have a high reproductive rate, can readily move into new areas and can change their behavior to avoid being captured or killed.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/RpwHJT4t-Zo?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Minnesota wildlife experts are keeping a wary eye on their northern border for signs of wild ‘super pigs’ moving down from Canada.</span></figcaption>
</figure>
<h2>Omnivores on the hoof</h2>
<p>Much concern over the spread of wild pigs has focused on economic damage, which was recently estimated at <a href="https://www.usatoday.com/story/news/nation/2023/11/21/which-states-have-the-worst-wild-hog-problem/71658126007/">about US$2.5 billion annually</a> in the United States.</p>
<p>Wild pigs have a unique collection of traits that make them problematic to humans. When we told one private landowner about the results from our studies, he responded: “That makes sense. Pigs eat all the stuff the other wildlife do – they just eat it first, and then they go ahead and eat the wildlife, too. They pretty much eat anything with a calorie in it.” </p>
<p>More scientifically, wild pigs are called extreme generalist foragers, which means they can survive on many different foods. A <a href="https://doi.org/10.1111/mam.12015">global review of their dietary habits</a> found that plants represent 90% of their diet – primarily agricultural crops, plus the fruits, seeds, leaves, stems and roots of wild plants.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/566078/original/file-20231215-23-4f6gba.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A male lesser prairie-chicken inflates his orange throat sacs to call potential mates." src="https://images.theconversation.com/files/566078/original/file-20231215-23-4f6gba.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566078/original/file-20231215-23-4f6gba.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=406&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566078/original/file-20231215-23-4f6gba.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=406&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566078/original/file-20231215-23-4f6gba.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=406&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566078/original/file-20231215-23-4f6gba.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=510&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566078/original/file-20231215-23-4f6gba.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=510&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566078/original/file-20231215-23-4f6gba.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=510&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Lesser prairie chickens are a ground-nesting species – found in parts of Colorado, Kansas, New Mexico, Oklahoma and Texas – that is listed under the Endangered Species Act. Feral hogs prey on the birds and their eggs and damage the birds’ habitat by rooting up and consuming native plants and spreading invasive plant seeds.</span>
<span class="attribution"><a class="source" href="https://www.fws.gov/media/lesser-prairie-chicken-lek">Greg Kramos/USFWS</a></span>
</figcaption>
</figure>
<p>Wild pigs also eat most small animals, along with fungi and invertebrates such as insect larvae, clams and mussels, particularly in places where pigs are not native. For example, a 2019 study reported that wild pigs were digging up eggs laid by endangered loggerhead sea turtles on an island off the coast of South Carolina, <a href="https://doi.org/10.1016/j.actao.2019.103442">reducing the turtles’ nesting success to zero in some years</a>.</p>
<p>And these pigs do “just eat it first.” They compete for resources that other wildlife need, which can have <a href="http://dx.doi.org/10.1007/s10530-012-0229-6">negative effects on other species</a>. </p>
<p>However, they likely do their most severe damage through predation. Wild pigs kill and eat rodents, deer, birds, snakes, frogs, lizards and salamanders. This probably best explains why colleagues and I found in <a href="https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/ece3.5360">one study</a> that forest patches with wild pigs had 26% fewer mammal and bird species than similar forest patches without pigs. </p>
<p>This decrease in diversity was similar to that found with <a href="https://doi.org/10.1016/bs.aecr.2016.10.002">other invasive predators</a>. And our findings are consistent with a global analysis showing that invasive mammalian predators that have no natural predators themselves – especially generalist foragers like wild pigs – <a href="https://doi.org/10.1073/pnas.1602480113">cause by far the most extinctions</a>. </p>
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<h2>Altering ecosystems</h2>
<p>Many questions about wild pigs’ ecological impacts have yet to be answered. For example, they may harm other wild species indirectly, rather than eating them or depleting their food supply. </p>
<p>Our work shows that wild pigs <a href="https://doi.org/10.1016/j.fooweb.2022.e00270">can alter the behavior of common native wildlife species</a>, such as raccoons, squirrels and deer. Using trail cameras, we found that when wild pigs were present, other animals altered their activity patterns in various ways to avoid them. Such shifts may have additional cascading effects on ecosystems, because they change how and when species interact in the food web.</p>
<p>Another major concern is wild pigs’ potential to spread disease. They carry numerous pathogens, including brucellosis and tuberculosis. However, little ecological research has been done on this issue, and scientists have not yet demonstrated that an increasing abundance of wild pigs reduces the abundance of native wildlife via disease transmission. </p>
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<figcaption><span class="caption">Feral hogs can be seen rooting up the soil in this trail camera footage from Alabama.</span></figcaption>
</figure>
<p>Interestingly, in their native range in Europe and Asia, pigs do not cause as much ecological damage. In fact, some studies indicate that they may <a href="http://biozoojournals.ro/nwjz/content/v13n2/nwjz_e161706_Baruzzi.pdf">modify habitat in important ways</a> for species that have evolved with them, such as frogs and salamanders. </p>
<p>So far, however, there is virtually no scientific evidence that feral pigs provide any benefits in North America. One <a href="http://dx.doi.org/10.1007/s10530-012-0229-6">review of wild pig impacts</a> discussed the potential for private landowners plagued with pigs to generate revenue from selling pig meat or opportunities to hunt them. And it’s possible that wild pigs could serve as an alternative food source for imperiled large predators, or that their wallowing and foraging behavior in some cases could mimic that of locally eradicated or extinct species. </p>
<p>But the scientific consensus today is that in North America, wild pigs are a growing threat to both ecosystems and the economy. It is unclear how invading super pigs would contribute to the overall threat, but bigger pigs likely cause more damage and are generally better predators and competitors. </p>
<p>While efforts to control wild pigs <a href="https://www.nrcs.usda.gov/feral-swine-eradication-and-control-pilot-program">are well underway</a> in the U.S., incursions by Canadian super pigs may complicate the job. Invasive super pigs make for catchy headlines, but their potential effects are no joke.</p>
<p><em>This is an updated version of <a href="https://theconversation.com/feral-pigs-harm-wildlife-and-biodiversity-as-well-as-crops-120066">an article</a> originally published on Aug. 26, 2019.</em></p><img src="https://counter.theconversation.com/content/218899/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Marcus Lashley receives funding from USDA Wildlife Services.</span></em></p>Feral hogs are one of the most destructive invasive species in North America, harming land, crops and wildlife.Marcus Lashley, Associate Professor of Wildlife Ecology, University of FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2194642023-12-14T13:12:30Z2023-12-14T13:12:30ZArtificial light lures migrating birds into cities, where they face a gauntlet of threats<figure><img src="https://images.theconversation.com/files/565500/original/file-20231213-21-30h0uo.jpg?ixlib=rb-1.1.0&rect=33%2C33%2C7315%2C4869&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The New York City borough of Manhattan at night, viewed from the Rockefeller Center observation deck.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/manhattan-skyline-with-view-to-empire-state-building-from-news-photo/1749117051">Sergi Reboredo/VW Pics/Universal Images Group via Getty Images</a></span></figcaption></figure><p>Light pollution has steadily intensified and expanded from urban areas, and with the <a href="https://doi.org/10.1582/LEUKOS.2010.06.04001">advent of LED lighting</a>, it is growing in North America by <a href="http://dx.doi.org/10.1126/science.abq7781">up to 10% per year</a>, as measured by the visibility of stars in the night sky. In our <a href="https://doi.org/10.1038/s41467-023-43046-z">recent study</a>, we found that the glow from cities and urban outskirts can powerfully attract migratory birds, drawing them into developed areas where food is scarcer and they face threats such as colliding with glass buildings.</p>
<p>Each spring and fall, migratory birds journey to or from their breeding grounds, <a href="https://www.allaboutbirds.org/guide/Bobolink/maps-range">sometimes traveling thousands of miles</a>. En route, most birds need to <a href="http://dx.doi.org/10.1111/ele.13618">make stopovers</a> to rest and feed. Some species burn off half of their body mass during migration.</p>
<p>Migratory stopover sites are not random, and birds typically use the same locations from year to year. Because migration takes place on a continental scale, with <a href="https://abcbirds.org/blog/north-american-bird-flyways/">billions of birds crossing North America</a> each migratory season, it’s important for scientists to understand what attracts birds to these locations. </p>
<p>We found that light pollution was a top predictor of the density of migrating birds at stopover locations for both spring and fall migration across the continental U.S.</p>
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<figcaption><span class="caption">Artificial light at night is an expanding threat to migrating birds, drawing them into developed areas where they can die from collisions with buildings and are exposed to other threats.</span></figcaption>
</figure>
<h2>Why it Matters</h2>
<p>Nearly all birds in North America – some 80% – migrate each spring and fall. And of those species that migrate, <a href="https://doi.org/10.1002/fee.2029">70% travel at night</a>. </p>
<p>Nocturnal migration has many adaptive benefits: For example, the weather conditions are better, and fewer predators are active. But it makes most migratory birds highly susceptible to light pollution. In North America alone, it is estimated that up to 1 billion migrating birds <a href="https://doi.org/10.1650/CONDOR-13-090.1">die each year from collisions with buildings</a>. </p>
<p>Scientists don’t yet know why nocturnally migrating birds are attracted to artificial light, but research has shown that light pollution <a href="https://doi.org/10.1016/j.tree.2022.12.006">acts as an amplifying agent</a> that draws more songbirds into urbanized areas. It often <a href="https://doi.org/10.1111/geb.13466">co-occurs with other environmental threats</a>, such as water and air pollution and noise. All of these stressors disrupt birds’ behavioral and physiological processes during journeys that already are extremely taxing.</p>
<p>Lighting is part of the fabric of human structures, yet many people don’t think of it as a pollutant or perceive its harmful effects on nature – until events like the <a href="https://chicago.suntimes.com/2023/10/6/23906778/birds-killed-migration-collision-mccormick-place-lakeside-center">mass bird loss in Chicago</a> on Oct. 4-5, 2023, when nearly 1,000 birds were killed after colliding with the McCormick Place Convention Center, make the problem impossible to ignore.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/565502/original/file-20231213-15-ti0ti3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A black bird with an orange underside perches on a branch next to half an orange placed there for feeding." src="https://images.theconversation.com/files/565502/original/file-20231213-15-ti0ti3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/565502/original/file-20231213-15-ti0ti3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=445&fit=crop&dpr=1 600w, https://images.theconversation.com/files/565502/original/file-20231213-15-ti0ti3.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=445&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/565502/original/file-20231213-15-ti0ti3.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=445&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/565502/original/file-20231213-15-ti0ti3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=560&fit=crop&dpr=1 754w, https://images.theconversation.com/files/565502/original/file-20231213-15-ti0ti3.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=560&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/565502/original/file-20231213-15-ti0ti3.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=560&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Baltimore orioles migrate twice yearly between their wintering grounds in Florida, the Caribbean and Latin America and their summer breeding zones, which stretch from Louisiana into central Canada.</span>
<span class="attribution"><span class="source">Kyle Horton</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>How we did our work</h2>
<p>With colleagues at Colorado State University, Michigan State University, the University of Delaware, the Cornell Lab of Ornithology, Princeton University, the University of Massachusetts Amherst and the National Park Service, we sought to understand the complex drivers and large-scale patterns of stopover density by combining remote sensing data with geospatial tools. Mapping stopover locations has been a bird conservation priority for many years; now, for the first time, we have a complete view of where these stopovers are across the United States.</p>
<p>We were able to make novel maps at a continental scale using <a href="https://www.ncei.noaa.gov/products/radar/next-generation-weather-radar">U.S. NEXRAD weather surveillance data</a> – information from the same radars that meteorologists draw on to predict weather patterns on television and weather apps. We created 2,500 models using roughly 1 million locations across the U.S. and 49 predictor variables, including forest cover, precipitation, temperature, elevation and <a href="https://www.energy.gov/eere/ssl/text-alternative-version-what-sky-glow">skyglow</a> – diffuse brightness in the night sky from artificial light.</p>
<p>These maps capture fine-scale details that allow us to see increased densities of migrating birds following the winding banks of the Mississippi River, which provide an important refuge for depleted migrants to rest and refuel. We also created fall and spring hotspot maps highlighting regions where especially high numbers of birds made stopovers. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/565636/original/file-20231213-21-au4a3l.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Radar imagery showing masses of light and dark blue above a map of St. Louis." src="https://images.theconversation.com/files/565636/original/file-20231213-21-au4a3l.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/565636/original/file-20231213-21-au4a3l.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/565636/original/file-20231213-21-au4a3l.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/565636/original/file-20231213-21-au4a3l.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/565636/original/file-20231213-21-au4a3l.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/565636/original/file-20231213-21-au4a3l.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/565636/original/file-20231213-21-au4a3l.gif?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">Radar detecting migrating birds lifting off from the St. Louis landscape on the night of May 10, 2023. Density of bird flocks increases from light blue to dark blue to green.</span>
<span class="attribution"><span class="source">Kyle Horton</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>We found that the presence of light pollution was a better predictor of bird densities than temperature, precipitation or tree canopy cover. These all were variables that we had expected to correlate with periods when birds would be on the ground, or with high-quality habitats where birds would be likely to stop over. </p>
<p>Other variables were associated with areas that birds were unlikely to use as stopovers. One example was the presence of agricultural crops, such as corn or soybeans. Fields planted with a single crop <a href="https://doi.org/10.1073/pnas.2203511120">don’t provide adequate food or shelter for many bird species</a>, so migrants are unlikely to rest there.</p>
<p>Light pollution is a human-induced change to the environment that may act as an <a href="https://doi.org/10.1016/j.cois.2021.02.004">ecological trap</a>, drawing birds into substandard habitats and increasing their risk of collisions with buildings. Happily, its immediate effects can be quickly reversed with the flip of a switch. </p>
<p>Working to reduce artificial light through <a href="https://tx.audubon.org/urbanconservation/lights-out-texas">Lights Out campaigns</a> and <a href="https://aeroecolab.com/uslights">migration alerts</a>, <a href="http://dx.doi.org/10.1111/cobi.13740">understanding when birds will be in airspaces</a> and <a href="https://www.audubon.org/bird-friendly-buildings">using bird-friendly glass</a> that has patterns across its surface to make it more visible to birds, will reduce bird deaths from light pollution. Understanding the drivers and macro-scale patterns of stopover densities across the continental U.S. will better inform conservation actions like these. </p>
<p><em>The <a href="https://theconversation.com/us/topics/research-brief-83231">Research Brief</a> is a short take on interesting academic work.</em></p><img src="https://counter.theconversation.com/content/219464/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kyle Horton receives funding from the National Science Foundation and the National Aeronautics and Space Administration. </span></em></p><p class="fine-print"><em><span>Carolyn S. Burt 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>Migrating birds need stopover locations en route where they can rest and feed. A new study shows that artificial light draws them away from sites they would normally use and into risky zones.Carolyn S. Burt, Convergence Research Coordinator, Department of Fish, Wildlife, and Conservation Biology, Colorado State UniversityKyle Horton, Assistant Professor of Fish, Wildlife, and Conservation Biology, Colorado State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2159202023-11-01T14:37:13Z2023-11-01T14:37:13ZGiraffes could go extinct – the 5 biggest threats they face<p>Giraffes are the world’s tallest mammals and an African icon, but they are also vulnerable to extinction. </p>
<p>Giraffe populations have <a href="https://www.iucnredlist.org/species/9194/136266699">declined</a> by 40% in the last 30 years, and there are now fewer than 70,000 mature individuals left in the wild. What are the causes of this alarming decline, and what can be done to protect these gentle giants? </p>
<p>The five biggest threats to giraffes are habitat loss, insufficient law enforcement, ecological changes, climate change, and lack of awareness. Below, I will tell you about these threats and what is being done to save them. </p>
<p>I will also explain a <a href="https://onlinelibrary.wiley.com/doi/10.1111/gcb.16970">study</a> I was a part of that ranked these threats in terms of each one’s danger of causing giraffe extinction, and whether human actions can alleviate that danger. The study used data from more than 3,100 giraffes identified over eight years in an unfenced 4,500km² area of the <a href="https://en.wikipedia.org/wiki/Tarangire_Ecosystem">Tarangire ecosystem</a> in Tanzania. We used the data to simulate how environmental and land use changes could affect the giraffe population over 50 years. </p>
<p>The findings can guide conservation actions.</p>
<h2>Habitat degradation, fragmentation and loss</h2>
<p>Giraffes need large areas of savanna with abundant native bushes and trees to feed on. The biggest threat to giraffes is the degradation, fragmentation and loss of their habitats through human activities such as farming and human settlement expansion.</p>
<p>Habitat loss outside protected areas is the main reason for the recent decline in giraffe numbers. National parks provide most of the remaining habitat. Some good habitat remains unprotected but is cared for by pastoralists. </p>
<p>Traditional pastoralists like the Maasai in northern Tanzania <a href="https://www.ucpress.edu/book/9780520273559/savannas-of-our-birth">maintain</a> large spaces of natural savanna where wildlife and people thrive together. </p>
<p>However, most people now living in areas that were giraffe habitat are sedentary. As populations of farmers and townspeople expand, giraffes are forced into smaller and more isolated patches of land. This <a href="https://doi.org/10.1016/j.anbehav.2019.01.017">reduces</a> their access to food and water, and increases their vulnerability. </p>
<p>Conservationists are working to safeguard existing unprotected giraffe habitat and maintain or restore the connections among protected areas. Community-based <a href="https://wildlife.onlinelibrary.wiley.com/doi/10.1002/jwmg.21549">natural resource management</a> is central to this activity. It gives local communities the legal power to protect their land and resources. </p>
<h2>Insufficient law enforcement</h2>
<p>Another major threat to giraffes is illegal hunting (<a href="https://esj-journals.onlinelibrary.wiley.com/doi/10.1007/s10144-015-0499-9">poaching</a>) for bushmeat markets. This is usually controlled by <a href="https://www.interpol.int/en/News-and-Events/News/2020/Wildlife-crime-closing-ranks-on-serious-crime-in-the-illegal-animal-trade">international criminal syndicates</a>. </p>
<p>Strong wildlife law enforcement is the best tool to combat this threat. Conservationists are working to strengthen local and international law enforcement around wildlife crimes, and to reduce the demand for giraffe products. At the grassroots level, this requires supporting anti-poaching patrols by rangers and village game scouts. It’s also essential that communities should have legal alternative ways to make a living. </p>
<h2>Ecological changes</h2>
<p>A third major threat to giraffes is human-caused ecological change that affects their food availability and mobility. These changes include deforestation of savannas for fuelwood and charcoal production, mining activity, and road and pipeline building. Water diversion and groundwater pumping also affect their habitat and access to water.</p>
<p>Mining, roads and pipelines can disrupt the <a href="https://doi.org/10.1007/978-3-030-93604-4_12">natural movement patterns</a> of wildlife, leading to smaller, more isolated populations that are more susceptible to local extinction. </p>
<p>Conservationists are promoting sustainable forestry, new cooking techniques such as gas stoves, water conservation and planning for groundwater resources, and building wildlife crossings into roads and pipelines.</p>
<h2>Climate change</h2>
<p>Climate change from human-caused <a href="https://digital.library.unt.edu/ark:/67531/metadc226754/m1/1/">carbon dioxide pollution</a> is forecast to increase temperatures and rainfall in many African savanna areas. Giraffes are unaffected by the higher temperatures observed so far, but increased seasonal rainfall is associated with <a href="https://link.springer.com/article/10.1007/s10531-023-02645-4">lower giraffe survival</a> due to disease and lower food quality. </p>
<p>Over the longer term, more rainfall will create conditions favourable to increased woody plant cover in savannas. This could help giraffes by increasing their food supply, but only if enough natural savanna is preserved from human exploitation.</p>
<h2>Lack of knowledge and awareness</h2>
<p>The fifth major threat to giraffes is the lack of knowledge and awareness about their conservation needs. Giraffes are often overlooked and underrepresented in wildlife research, funding and policy. Many people are unaware that giraffes are endangered and face multiple threats across Africa. </p>
<p>Conservationists are working to increase knowledge and awareness about giraffes locally and worldwide. Scientists are studying giraffe <a href="https://doi.org/10.1002/jwmg.22044">demography</a>, <a href="https://doi.org/10.1093/jmammal/gyac007">diet</a>, <a href="https://doi.org/10.1111/1365-2656.13582">behaviour</a> and <a href="https://onlinelibrary.wiley.com/doi/10.1002/ece3.10160">genetics</a>, and there is a large <a href="https://www.africasgiants.org/natures-giants-news">environmental education programme</a> in Tanzania, the US and Europe. </p>
<h2>Creating a safe future for giraffes</h2>
<p>Giraffes are facing a silent extinction crisis in Africa. But there is still hope that they can be saved if people understand and address the threats. </p>
<p>The new <a href="https://onlinelibrary.wiley.com/doi/10.1111/gcb.16970">study</a> I coauthored ranked threats and looked at potentially mitigating actions. Our simulation showed that the greatest risk factor for local giraffe extinction was a reduction in wildlife law enforcement leading to more poaching. In the model, an increase in law enforcement would mitigate the negative effects of climate change and the expansion of towns along the edges of protected areas. The study highlights the great utility of law enforcement as a nature conservation tool. </p>
<p>Given their vast historical Africa-wide range and <a href="https://www.sciencedirect.com/science/article/abs/pii/S0003347219300260">individual home ranges</a> of thousands of hectares, giraffes will not likely survive only within the boundaries of small, fragmented protected areas. I propose as part of our evidence-based recommendations that rangelands used by wildlife and pastoralists as movement pathways be permanently protected from farming, mining and infrastructure. This will give people as well as wide-ranging animals like giraffes freedom to roam. </p>
<p>It will also require the expansion of wildlife law enforcement in village lands outside formal protected areas. </p>
<p>These measures would help make it possible for people and giraffes to thrive together.</p><img src="https://counter.theconversation.com/content/215920/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Derek E. Lee receives funding from Penn State University, Berlin World Wild, Sacramento Zoo, Columbus Zoo, Living Desert Zoo and Gardens, Tulsa Zoo, Zoo Miami, Cincinnati Zoo, Como Park Zoo, Roger Williams Park Zoo, Anne Innis Dagg Foundation, and Save the Giraffes. He is affiliated with Wild Nature Institute.</span></em></p>Giraffes are vulnerable to extinction, mainly due to habitat loss and killing for bushmeat markets. The good news is human actions can alleviate that danger.Derek E. Lee, Associate Research Professor of Biology, Penn StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2102632023-08-30T12:15:57Z2023-08-30T12:15:57ZGiraffes range across diverse African habitats − we’re using GPS, satellites and statistics to track and protect them<figure><img src="https://images.theconversation.com/files/544746/original/file-20230825-17-am7gat.jpeg?ixlib=rb-1.1.0&rect=11%2C0%2C3768%2C2345&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An average giraffe has a home range almost as large as Philadelphia.</span> <span class="attribution"><span class="source">Michael Brown</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>Nearly 6,000 years ago, our ancestors climbed arid rocky outcrops in what is now the Nigerian Sahara and carved spectacularly intricate, larger-than-life renditions of giraffes into the exposed sandstone. The remarkably detailed Dabous giraffe rock art petroglyphs are among <a href="https://journals.co.za/doi/pdf/10.10520/AJA00382353_1067">many ancient petroglyphs featuring giraffes across Africa</a> – a testament to early humans’ fascination with these unique creatures. </p>
<p>We are still <a href="https://doi.org/10.1371/journal.pone.0199149">captivated by giraffes today</a>, but many of these animals are at risk, largely due to habitat loss and illegal hunting. Some <a href="https://giraffeconservation.org/programmes/giraffe-conservation-status-assessment/">are critically endangered</a>. </p>
<p>To understand how giraffes are faring across Africa, <a href="https://scholar.google.com/citations?user=f3D2QOcAAAAJ&hl=en">conservation ecologists like me</a> are studying how they interact with their habitats across vast geographic scales. We use space-age technology and advanced statistical approaches that our ancient ancestors could have scarcely imagined to understand how giraffes can better coexist with people. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Image of a giraffe carved in red rock." src="https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.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">Giraffes are featured prominently in ancient petroglyphs across Africa, such as this one in Twyfelfontein, Namibia, which dates back thousands of years.</span>
<span class="attribution"><span class="source">Michael Brown</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Many habitats and challenges</h2>
<p>Giraffes may all look similar to the casual viewer, but in fact there are <a href="https://doi.org/10.1016/j.cub.2021.04.033">four distinct species</a>. By our best estimates, there are <a href="https://doi.org/10.1016/B978-0-12-821139-7.00139-2">roughly 117,000 giraffes remaining in the wild</a>, living in <a href="https://doi.org/10.1111/mam.12165">21 African countries</a>. </p>
<p>Across this huge expanse, giraffes make their homes in many different environments with varied levels of human influence. For example, in the relatively arid Sahel region of Niger, they live among communal farmers entirely outside of formally protected areas. In contrast, along the Nile in Uganda’s national parks, they browse through lush savannas that are formally protected by dedicated rangers. </p>
<p>Each of these areas has unique bioclimatic conditions and conservation philosophies. There is <a href="https://giraffeconservation.org/programmes/conservation-strategies/">no one-size-fits-all approach</a> for protecting giraffe habitats and <a href="https://doi.org/10.1080/10871209.2021.1885768">promoting coexistence with people</a>. </p>
<p>Researchers are taking advantage of these diverse conditions to learn how giraffes move throughout this range. <a href="https://doi.org/10.1098/rspb.2023.0912">In a recently published paper</a>, I worked with colleagues from academia and conservation organizations to conduct the largest ever tracking study to better understand how and why giraffes move at large scales. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Four images of giraffes in diverse African settings." src="https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=300&fit=crop&dpr=1 600w, https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=300&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=300&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=377&fit=crop&dpr=1 754w, https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=377&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=377&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 four species of giraffes inhabit remarkably different habitats across Africa, from lush savannas to desert.</span>
<span class="attribution"><span class="source">Michael Brown</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Tracking wide-ranging animals</h2>
<p>Over the past decade, our collaborative conservation research team, spearheaded by the <a href="https://giraffeconservation.org/">Giraffe Conservation Foundation</a>, has embarked on an ambitious pan-African giraffe-tracking study to better understand giraffes’ movements across these diverse landscapes. </p>
<p>Each tracking operation contributes to local studies by telling us something interesting about giraffe behavior. For example, we published the first description of <a href="https://doi.org/10.3389/fevo.2019.00524">partial migration in a Ugandan giraffe population</a>, showing that giraffes can have complicated seasonal movements. </p>
<p>These studies also are important for guiding local management of giraffes. Partnering with organizations like <a href="https://www.earthranger.com/">EarthRanger</a>, which develops software to support conservation initiatives, we have pioneered the use of animal movement data to inform active conservation management. </p>
<p>We share giraffe location data in real time with rangers in protected areas to guide day-to-day conservation actions. As an example, we run continuous analytics on the giraffe data that alert teams on the ground when a giraffe stops moving or leaves the boundaries of a national park. With this information, teams can follow up quickly and address risks, such as when giraffes might be straying into dangerous areas.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Bry-gJU-cis?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">In October 2021, conservation scientists and local wildlife officials translocated 10 South African giraffes over 1,600 miles (2,600 kilometers) from South Africa to Malawi. There they joined 13 giraffes already in Majete Wildlife Reserve, helping to expand the group into a sustainable population.</span></figcaption>
</figure>
<p>To look at these patterns at a larger scale in our recent study, we analyzed GPS tracking data from 148 giraffes, representing all four species from across 10 countries. We wanted to understand how giraffes may change their movements in response to human pressures and the availability of vegetation.</p>
<p>We used environmental data from satellite imagery, linking the giraffes’ locations to the exact conditions that the animals were moving through. Since the work drew from information collected across Africa through different GPS devices, we developed statistical techniques to harmonize the datasets and make the results directly comparable across ecosystems. </p>
<p>Overall, we found that giraffes cover impressively large areas. On average, each animal has a home range of about 140 square miles (360 square kilometers) – <a href="https://www.census.gov/quickfacts/fact/table/philadelphiacitypennsylvania/PST045222">nearly equivalent to the surface area of Philadelphia</a> – and travels about 8.5 miles (14 kilometers) every day. One of the biggest movers in our study, a female northern giraffe in Niger that navigated among communities raising livestock in the dry Sahel, covered a home range of nearly 1,500 square miles (3,860 square kilometers) – larger than the <a href="https://www.ri.gov/facts/history.php">land area of Rhode Island</a>. </p>
<p>Giraffes’ movements changed significantly based on the availability of woody vegetation and the level of human presence. Those in areas with plenty of woody vegetation didn’t cover as much ground as their counterparts in more barren zones, since the former had most of the resources they needed close by. Giraffes also tended to move less in places with significant human development – probably because of man-made barriers to their movements, like settlements, fences and roads.</p>
<p>In mixed areas with some development and some open spaces, we observed that giraffes covered more ground as they navigated these patchy environments. They traveled faster and covered larger areas when they were moving between resource-rich zones and more heavily developed areas.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Two giraffes at the edge of a road watch a car pass." src="https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.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">Across their range, giraffes are navigating increasingly developed landscapes.</span>
<span class="attribution"><span class="source">Michael Brown, GCF</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Giraffe movements inform conservation</h2>
<p>Understanding how giraffes respond to changes in environmental conditions is critical for their conservation. Climate change is making the availability of vegetation less predictable, and human populations in these areas are continuing to grow. Conservation strategies will need to account for giraffes’ changing movements as the animals respond to these shifts. </p>
<p>It also is important to develop principles for giraffe movement so that we can better predict how they might move in new environments. Conservation groups and governments are increasingly using <a href="https://giraffeconservation.org/programmes/conservation-translocations/">conservation translocations</a> – capturing wild giraffes and moving them to new habitats – as a tool to reestablish populations in areas where giraffes had previously become extinct. </p>
<p>Our movement data from giraffes across Africa is casting new light on their responses to different conditions and providing important information for conserving these iconic animals in a rapidly changing world.</p><img src="https://counter.theconversation.com/content/210263/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Brown works for the Giraffe Conservation Foundation and is an affiliated researcher for the Smithsonian National Zoo and Conservation Biology Institute. He receives funding from the Giraffe Conservation Foundation and its many supporters and is affiliated with the Smithsonian National Zoo and Conservation Biology Institute.</span></em></p>The largest ever giraffe tracking study shows how these massive animals are responding to human pressures across many different habitats throughout Africa.Michael Brown, Conservation Science Fellow, Smithsonian InstitutionLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2121082023-08-29T04:26:14Z2023-08-29T04:26:14ZHow a lethal fungus is shrinking living space for our frogs<p>In 1993, frogs were found dying <a href="https://www.pnas.org/doi/full/10.1073/pnas.95.15.9031">en masse</a> in Far North Queensland. When scientists analysed their bodies, they found something weird. Their small bodies were covered in spores. </p>
<p>It was an epidemic. An aquatic fungus had eaten the keratin in their skin, compromising its function and leading to cardiac arrest. And worse, the amphibian chytrid fungus (<em>Batrachochytrium dendrobatidis</em>) had been quietly spreading around the world, from South America to Europe, killing frogs wherever it went. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/545151/original/file-20230829-19-2sjqta.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/545151/original/file-20230829-19-2sjqta.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/545151/original/file-20230829-19-2sjqta.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=481&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545151/original/file-20230829-19-2sjqta.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=481&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545151/original/file-20230829-19-2sjqta.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=481&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545151/original/file-20230829-19-2sjqta.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=605&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545151/original/file-20230829-19-2sjqta.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=605&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545151/original/file-20230829-19-2sjqta.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=605&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">It doesn’t look lethal – but looks can be deceiving. This is a chytrid zoosporangium, which will release zoospores that propel themselves through water in search of amphibian hosts.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Batrachochytrium_dendrobatidis#/media/File:CSIRO_ScienceImage_1392_Scanning_Electron_Micrograph_of_Chytrid_Fungus.jpg">CSIRO/Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Likely native to the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6311102/">Korean Peninsula</a>, it was first detected in Australia in the <a href="https://www.sciencedirect.com/science/article/pii/S0006320716310126">late 1970s</a>. As it spread, it <a href="https://www.sciencedirect.com/science/article/pii/S0006320716310126">caused the extinction</a> of at least four Australian frog species and probably three others. </p>
<p>This lethal pathogen is a selective killer. As our <a href="https://www.nature.com/articles/s41559-023-02155-0">new research</a> shows, it effectively makes some areas a no-go zone for susceptible frog species. The fungus doesn’t like hot conditions. But in cooler environments – such as in southern Australia and higher up in mountain ranges – it flourishes. Mortality rates in these environments can approach 100% for some frog species. </p>
<h2>Pushed from the highlands</h2>
<p>Australia is rich in frogs, with 247 surviving species at last count. Most are endemic to the continent – and many are spectacularly beautiful or, like the <a href="https://www.theguardian.com/culture/2022/feb/21/the-15-most-interesting-australian-frogs-sorted">turtle frog</a>, bizarre. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/545161/original/file-20230829-30-f0vm7l.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="turtle frog" src="https://images.theconversation.com/files/545161/original/file-20230829-30-f0vm7l.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/545161/original/file-20230829-30-f0vm7l.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545161/original/file-20230829-30-f0vm7l.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545161/original/file-20230829-30-f0vm7l.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545161/original/file-20230829-30-f0vm7l.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545161/original/file-20230829-30-f0vm7l.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545161/original/file-20230829-30-f0vm7l.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&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 turtle frog (Myobatrachus gouldii) is one of Australia’s strangest.</span>
<span class="attribution"><span class="source">Stephen Zozaya/Wikimedia</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>The gorgeous Australian lace-lid treefrog was once widespread across the rainforests of Queensland’s Wet Tropics, which run from Townsville to Cooktown, stretching from sea level up to Queensland’s highest mountain, the 1,622 metre Mt Bartle Frere. </p>
<p>Lace-lid treefrogs once lived throughout these forests, whether on mountains or down near sea level. But they have been driven from rainforests above 400 metres. Down lower, the heat makes it harder for chytrid to kill, and the frog’s higher breeding rate can outpace deaths from the disease. </p>
<h2>No-go zones</h2>
<p>Australians know full well about the damage introduced species can do. Cane toads kill native predators like quolls who aren’t used to their toxin. Cats and foxes have driven many small mammals to extinction. </p>
<p>But even when a species survives contact with an introduced species, it can be forever changed. </p>
<p>That’s because of less visible effects introduced species like chytrid fungus can have, such as shrinking the areas where native species can survive. When this happens, our species can be pushed into smaller parts of their original range, known as environmental refuges. </p>
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Read more:
<a href="https://theconversation.com/the-worlds-worst-animal-disease-is-killing-frogs-worldwide-a-testing-breakthrough-could-help-save-them-205872">The world's worst animal disease is killing frogs worldwide. A testing breakthrough could help save them</a>
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<p>As our research shows, it’s not just geographic range that changes. It also changes their niche – the set of environmental conditions where species can survive. Introduced species can actually force much larger contractions to a native species’ niche than to its geographic range. </p>
<p>You might wonder how that can be. It’s because the damage done by introduced species can vary a lot depending on the environment. Introduced species have their own niche – climates and environments where they thrive, and areas where they don’t. </p>
<p>Frog species that survived the initial epidemics don’t just persist in random parts of their old range. Hotter, wetter areas or those with less temperature variability become refuges. Chytrid is still widespread here, but it’s less lethal. </p>
<p>Part of the puzzle is also the fact these refuge areas are naturally easier places for frogs to survive and reproduce. Where populations thrive, they have greater resilience and stand a better chance of surviving the fungus. </p>
<h2>Pushed into refuges</h2>
<p>The pattern we document isn’t just seen in frogs. Researchers suspect similar changes have been forced on many native species impacted by introduced species. </p>
<p>Consider the bush-stone curlew – a long-legged, endearing bird with eerie <a href="https://www.youtube.com/watch?v=gqZsdBF-eKg&ab_channel=Janegrowsgardenrooms">night cries</a>. Many of us will have seen them haunting parks and beer gardens across northern Australia. But the same bird is now extinct or critically endangered in southern Australia, where it used to roam. Why? </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/545164/original/file-20230829-15-qleqn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="bush-stone curlew" src="https://images.theconversation.com/files/545164/original/file-20230829-15-qleqn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/545164/original/file-20230829-15-qleqn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545164/original/file-20230829-15-qleqn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545164/original/file-20230829-15-qleqn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545164/original/file-20230829-15-qleqn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545164/original/file-20230829-15-qleqn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545164/original/file-20230829-15-qleqn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Bush-stone curlews are lanky, unusual birds with a distinctive call.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Habitat loss has played a role, but this species is <a href="https://www.publish.csiro.au/mu/mu02029">highly susceptible</a> to foxes. Foxes don’t much like the humidity of tropical and subtropical Australia. As a result, the curlew has been pushed out of the drier parts of its niche. </p>
<p>Niche contractions due to introduced species are likely to be widespread but little-studied. </p>
<p>If a species has a shrinking niche, it may change where conservationists direct their efforts. To give threatened species the best chance of survival, we might have to direct our energies to safeguarding them in their environmental refuges, safe from introduced predators or diseases.</p>
<p>When scientists assess how a species is going, we often look at changes in geographic range to gauge the level of risk to the species, from vulnerable through to extinct in the wild. </p>
<p>But this can have limitations. What our work has shown is that the survivable niche for species can shrink much more than its geographic range, reducing resilience to new environmental challenges. If frog species are forced out of upland areas, they may be at more risk from climate change, given higher elevations are likely to be <a href="https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/eap.1824">most resilient</a> to climate change. </p>
<p>There’s a silver lining here, though. Species can be more resilient than we assume in the face of new threats. Some populations may be hard hit, while others escape. Understanding why that is will be key to give our native species the best chance of surviving an uncertain future. </p>
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Read more:
<a href="https://theconversation.com/a-deadly-disease-has-driven-7-australian-frogs-to-extinction-but-this-endangered-frog-is-fighting-back-189491">A deadly disease has driven 7 Australian frogs to extinction – but this endangered frog is fighting back</a>
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<img src="https://counter.theconversation.com/content/212108/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Geoffrey Heard is a member of the Terrestrial Ecosystem Research Network at the University of Queensland, which is funded under the National Collaborative Research Infrastructure Strategy (NCRIS). The Threatened Species Index, of which Geoffrey Heard is a Science Advisor, has received co-funding from the Department of Climate Change, Energy, the Environment and Water of the Australian Government.</span></em></p><p class="fine-print"><em><span>Benjamin Scheele receives funding from the Australian Research Council. </span></em></p><p class="fine-print"><em><span>Conrad Hoskin receives funding from the Department of Environment and Science (Queensland Government) and the Australian Research Council (ARC). He is affiliated with the College of Science and Engineering, James Cook University (Townsville, Australia).</span></em></p><p class="fine-print"><em><span>Jarrod Sopniewski is supported by a Hackett Postgraduate Research Scholarship at the University of Western Australia.</span></em></p><p class="fine-print"><em><span>Jodi Rowley has received funding from the Department of Agriculture, Water and the Environment, the Australian Museum Foundation and other state, federal and philanthropic agencies.</span></em></p>Introduced species and diseases can drive native species into smaller environmental niches – and that could mean change to how we work to conserve them.Geoffrey Heard, Research fellow, Australian National University and, The University of QueenslandBenjamin Scheele, Research Fellow in Ecology, Australian National UniversityConrad Hoskin, Senior Lecturer, College of Science & Engineering, James Cook UniversityJarrod Sopniewski, PhD student, The University of Western AustraliaJodi Rowley, Curator, Amphibian & Reptile Conservation Biology, Australian Museum, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2103322023-08-03T14:37:30Z2023-08-03T14:37:30ZConflict between humans and wildlife in Tanzania is being poorly managed – and climate change is making things worse<figure><img src="https://images.theconversation.com/files/539924/original/file-20230728-25-3kbixh.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Elephants are being forced into confrontations with humans</span> <span class="attribution"><span class="source">Wikimedia Commons</span></span></figcaption></figure><p>Human-wildlife conflicts are a challenge for authorities in African countries where people live near protected areas. Programmes for communities to participate in wildlife tourism and share its benefits have been put forward as one solution. </p>
<p>Those benefits are substantial in Tanzania. Wildlife tourism is a major source of foreign revenue for the country. In 2021, the tourism sector <a href="https://www.tanzaniainvest.com/tourism">generated</a> US$2.6 billion, or 5.7% of gross domestic product (GDP). </p>
<p>The country’s <a href="https://www.parliament.go.tz/polis/uploads/bills/acts/1662104063-CHAPTER%20283-THE%20WILDLIFE%20CONSERVATION%20ACT.pdf">2022 Wildlife Conservation Act</a> offers financial and material compensation for any eligible person negatively affected by human-wildlife conflict incidents. Between <a href="https://academicjournals.org/journal/IJBC/article-abstract/9D1C40570983">2012 and 2019</a>, more than 1,000 human-wildlife mortality cases were reported nationwide, with rural residents forming the large majority of the victims.</p>
<p>As a sustainability scholar with a research interest in farming and the environment, I set out to understand the experiences of people who’d been victims of human-wildlife conflict in Tanzania. In my <a href="https://academicjournals.org/journal/IJBC/article-abstract/9D1C40570983">study</a>, I spoke with people in the villages of Kiduhi and Mbamba. These two villages share borders with the <a href="https://www.mikuminationalpark.net/">Mikumi National Park</a>, the fourth-biggest national park in Tanzania. </p>
<p>I asked them about what drives human-wildlife conflict, in their view, when and how they experienced it, how it affected their livelihood or well-being, and what could be done to prevent it in the future. </p>
<p>Incidents of human-wildlife conflict had become common in the two villages, but I found that the victims’ experiences were underreported. I also found that the conflict was driven by habitat losses that pushed wild animals from the park to seek food and water outside. Changing weather patterns also played a role in tensions between wild animals from the park and residents of Kiduhi and Mbamba. Other <a href="https://www.nature.com/articles/s41558-023-01608-5#Abs1">research</a> has linked changing patterns like this to climate change. </p>
<h2>Water scarcity and loss of grassland</h2>
<p>Villagers in Kiduhi and Mbamba believed that a decrease in rainfall and long periods of drought were what drove elephants, hyenas and lions to seek food outside the park. This claim from residents was echoed by wildlife experts from Mikumi National Park. </p>
<p>They said the lack of rainfall led to a loss of vegetation inside Mikumi, forcing large animals like elephants to forage further afield. Potential prey for lions, such as deer and wildebeest, also moved far away in search of food and water. As a result, lions and hyenas from the park targeted cattle and goats in neighbouring villages.</p>
<p>In Kiduhi, a predominantly Maasai community that keeps livestock, hyena attacks and killings of goats had become frequent, endangering the lives of residents. Some reported risking their lives by patrolling at night to protect their cattle and chase away hyenas that were reported to be frequently seen in the area. One victim in Kiduhi told me:</p>
<blockquote>
<p>In February 2021, a lion attacked my boma and killed 11 goats but ended up eating just one goat. Though the attack happened at midnight, the lion didn’t leave immediately; it stayed until early morning. I reported the incident to wildlife authorities, who came and freed the lion. But, to date, I have not been compensated for my loss.</p>
</blockquote>
<h2>Crop losses</h2>
<p>The research also found that elephants raiding neighbouring villages’ farms was the major cause of human-elephant conflict around the park. Victims from Mbamba reported that clashes between them and elephants happened almost every day from May to August, the peak harvest season. </p>
<p>Since most Mbamba residents are subsistence farmers, the damage that elephants cause to their farms has a devastating impact on livelihoods. Women expressed concerns about household food shortages because most of the food they produced was damaged by elephants from the park. One woman farmer said:</p>
<blockquote>
<p>For me, it happens almost every year; they raid and eat all the crops, especially maize and rice. I have now accepted that when I grow maize, I also grow for elephants because they come every season.</p>
</blockquote>
<h2>Poor response</h2>
<p>In Kiduhi, most Maasai men and women interviewed in this study felt the local government and park officals had not shown concern about the livestock losses they experienced from hyena and lion attacks. Despite their quest for compensation, they had received nothing but daily promises of resolution.</p>
<p>In Mbamba, some villagers said they didn’t bother to report losses because no action would be taken.</p>
<h2>What needs to be done about it</h2>
<p>Across Africa, <a href="https://www.pnas.org/doi/10.1073/pnas.1012972108">financial compensation</a> for victims of human-wildlife conflicts is a popular management policy. Though some conservation experts have <a href="https://www.pnas.org/doi/10.1073/pnas.1012972108">questioned</a> its effectiveness, proponents of financial payments argue that ignoring victims’ economic losses could make the situation worse. </p>
<p><a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0272272">Studies</a> in Tarangire and Serengeti national parks in Tanzania revealed that inadequate compensation schemes and limited engagement of neighbouring communities were the primary cause of retaliation killings in both parks. </p>
<p>So, firstly, the government needs to improve its compensation scheme. </p>
<p>Secondly, local climate conditions in Tanzania need attention. Longer periods of drought and water scarcity are <a href="https://www.frontiersin.org/articles/10.3389/fenvs.2021.674363/full">expected</a> in the coming years. Human-wildlife conflict cases may escalate. Despite <a href="https://www.frontiersin.org/articles/10.3389/fenvs.2021.674363/full">known evidence</a> of the devastating impact of climate change on wildlife resources, the government of Tanzania has been very slow in responding to these risks. </p>
<p>One practical intervention would be investing in nature-based solutions like restoring degraded land and water sources within the park and its neighbouring villages. This would reduce tensions over these resources. </p>
<p>Neglecting victims’ welfare, and a lack of tangible benefits of wildlife tourism to communities adjacent to protected areas, could pose a serious threat to the survival of wildlife. Concrete measures to address this complex conservation challenge are critical for Tanzania, given the significant contribution of wildlife tourism to its economy.</p><img src="https://counter.theconversation.com/content/210332/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This research project was funded by the National Geographic Society.</span></em></p>Measures to address tensions between wildlife and humans are critical for Tanzania.Evodius Waziri Rutta, Sustainability Researcher, Queen's University, OntarioLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2029202023-04-27T15:07:05Z2023-04-27T15:07:05ZHuman activities in Asia have reduced elephant habitat by nearly two-thirds since 1700, dividing what remains into ever-smaller patches<figure><img src="https://images.theconversation.com/files/522859/original/file-20230425-26-oskryk.jpg?ixlib=rb-1.1.0&rect=3%2C0%2C2492%2C1511&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Habitat loss has driven Asian elephants, like these foraging at a garbage dump in Sri Lanka, into human areas.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/in-this-photograph-taken-on-may-11-wild-elephants-rummage-news-photo/958346764">Lakruwan Wanniarachchi/AFP via Getty Images</a></span></figcaption></figure><p>Despite their iconic status and long association with humans, Asian elephants are one of the most endangered large mammals. Believed to number between 45,000 and 50,000 individuals worldwide, they are at risk throughout Asia due to human activities such as deforestation, mining, dam building and road construction, which have <a href="https://doi.org/10.1002/ecs2.1624">damaged numerous ecosystems</a>. </p>
<p>My colleagues and I wanted to know when human actions started to fragment wildlife habitats and populations to the degree seen today. We quantified these impacts by considering them through the needs of this species. </p>
<p>In a <a href="http://dx.doi.org/10.1038/s41598-023-30650-8">newly published study</a>, we examined the centuries-long history of Asian landscapes that once were suitable elephant habitat and often were managed by local communities prior to the colonial era. In our view, understanding this history and restoring some of these relationships may be the key to living with elephants and other large wild animals in the future. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/522847/original/file-20230425-14-twwigb.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Several elephants walk along a path parallel to a road with cars on it." src="https://images.theconversation.com/files/522847/original/file-20230425-14-twwigb.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/522847/original/file-20230425-14-twwigb.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/522847/original/file-20230425-14-twwigb.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/522847/original/file-20230425-14-twwigb.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/522847/original/file-20230425-14-twwigb.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/522847/original/file-20230425-14-twwigb.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/522847/original/file-20230425-14-twwigb.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">Although elephants can cross roads and other infrastructure, elephant habitats across Asia are increasingly hemmed in, with firm boundaries between human and wildlife spaces. These elephants are in Sri Lanka.</span>
<span class="attribution"><span class="source">Shermin de Silva</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>How have humans affected wildlife?</h2>
<p>It isn’t easy to measure human impacts on wildlife across a region as large and diverse as Asia and more than a century ago. Historical data for many species is sparse. Museums, for instance, only contain specimens collected from certain locations. </p>
<p>Many animals also have very specific ecological requirements, and there often isn’t sufficient data on these features at a fine scale going far into the past. For instance, a species might prefer particular microclimates or vegetation types that occur only at particular elevations.</p>
<p>For nearly two decades <a href="https://scholar.google.com/citations?user=wPzBt-EAAAAJ&hl=en">I’ve been studying Asian elephants</a>. As a species, these animals are breathtakingly adaptable: They can live in seasonally dry forests, grasslands or the densest of rain forests. If we could match the habitat requirements of elephants to data sets showing how these habitats changed over time, we knew that we could understand how land-use changes have affected elephants and other wildlife in these environments.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/5GmzakE1yRc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Fewer than 50,000 Asian elephants remain in the wild across 13 countries. Habitat loss is one of the main reasons for their decline.</span></figcaption>
</figure>
<h2>Defining elephant ecosystems</h2>
<p>The <a href="https://www.iucnredlist.org/species/7140/45818198">home-range sizes</a> of Asian elephants can vary anywhere from a few hundred square miles to a few thousand. But since we couldn’t know exactly where elephants would have been centuries ago, we had to model the possibilities based on where they occur today. </p>
<p>By identifying the environmental features that correspond to locations where wild elephants live now, we can distinguish places where they could potentially have lived in the past. In principle, this should represent “good” habitat.</p>
<p>Today many scientists are using this kind of model to identify particular species’ climatic requirements and predict how areas suitable for those species might shift under future climate change scenarios. We applied the same logic retrospectively, using land-use and land-cover types instead of climate change projections. </p>
<p>We drew this information from the <a href="https://luh.umd.edu/">Land-Use Harmonization (LUH2)</a> data set, released by a research group at the University of Maryland. The group mapped historical land-use categories by type, starting in the year 850 – long before the advent of nations as we know them today, with fewer large population centers – and extending up to 2015.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/522857/original/file-20230425-18-9z1dzq.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map showing active, possible and potential elephant range across Asia." src="https://images.theconversation.com/files/522857/original/file-20230425-18-9z1dzq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/522857/original/file-20230425-18-9z1dzq.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=452&fit=crop&dpr=1 600w, https://images.theconversation.com/files/522857/original/file-20230425-18-9z1dzq.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=452&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/522857/original/file-20230425-18-9z1dzq.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=452&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/522857/original/file-20230425-18-9z1dzq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=568&fit=crop&dpr=1 754w, https://images.theconversation.com/files/522857/original/file-20230425-18-9z1dzq.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=568&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/522857/original/file-20230425-18-9z1dzq.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=568&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Asian elephants live in countries with large human populations, and their range has been shrunk and fragmented. Their future depends on human attitudes toward elephants and their conservation.</span>
<span class="attribution"><a class="source" href="https://www.trunksnleaves.org/status-threats.html">Hedges et al., 2008, via Trunks & Leaves</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>My co-authors and I first compiled records of where Asian elephants have been observed in the recent past. We limited our study to the 13 countries that today still contain wild elephants: Bangladesh, Bhutan, Cambodia, China, India, Indonesia, Laos, Malaysia, Myanmar, Nepal, Sri Lanka, Thailand and Vietnam. </p>
<p>We excluded areas where elephant populations are prone to <a href="https://www.cnn.com/2021/06/20/asia/human-elephant-conflict-india-krithi-karanth-c2e-spc-intl-hnk/index.html">clashing with people</a>, such as intensively farmed landscapes and plantations, in order to avoid classifying these zones as “good” elephant habitat. We included areas with lighter human influence, such as selectively logged forests, because they actually contain great food for elephants.</p>
<p>Next, we used a machine-learning algorithm to determine what types of land use and land cover existed at our remaining locations. This allowed us to map out where elephants could potentially live as of the year 2000. By applying our model to earlier and later years, we were able to generate maps of areas that contained suitable habitat for elephants and to see how those areas had changed over the centuries.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/522862/original/file-20230425-24-dz2yar.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A line of elephants drinking at a reservoir." src="https://images.theconversation.com/files/522862/original/file-20230425-24-dz2yar.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/522862/original/file-20230425-24-dz2yar.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=282&fit=crop&dpr=1 600w, https://images.theconversation.com/files/522862/original/file-20230425-24-dz2yar.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=282&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/522862/original/file-20230425-24-dz2yar.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=282&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/522862/original/file-20230425-24-dz2yar.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=354&fit=crop&dpr=1 754w, https://images.theconversation.com/files/522862/original/file-20230425-24-dz2yar.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=354&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/522862/original/file-20230425-24-dz2yar.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=354&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 human-made features, like this reservoir in Sri Lanka, can also be resources for wildlife.</span>
<span class="attribution"><span class="source">Shermin de Silva</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Dramatic declines</h2>
<p>Land-use patterns <a href="https://doi.org/10.1111/j.1466-8238.2010.00540.x">changed significantly on every continent</a> starting with the Industrial Revolution in the 1700s and extending through the colonial era into the mid-20th century. Asia was no exception. </p>
<p>For most areas, we found that suitable elephant habitat took a steep dive around this time. We estimated that from 1700 through 2015 the total amount of suitable habitat decreased by 64%. More than 1.2 million square miles (3 million square kilometers) of land were converted for plantations, industry and urban development. With respect to potential elephant habitat, most of the change occurred in India and China, each of which saw conversion in more than 80% of these landscapes.</p>
<p>In other areas of Southeast Asia – such as a large hot spot of elephant habitat in central Thailand, which was never colonized – habitat loss happened more recently, in the mid-20th century. This timing corresponds to logging concurrent with the so-called <a href="https://www.britannica.com/event/green-revolution">Green Revolution</a>, which introduced industrial agriculture to many parts of the world. </p>
<h2>Could the past be the key to the future?</h2>
<p>Looking back at land-use change over centuries makes it clear just how drastically human actions have reduced habitat for Asian elephants. The losses that we measured greatly exceed estimates of “<a href="https://doi.org/10.1016/j.cub.2016.08.049">catastrophic” human impacts on so-called wilderness</a> or forests within recent decades.</p>
<p>Our analysis shows that if you were an elephant in the 1700s, you might have been able to range across 40% of the available habitat in Asia with no problem, because it was one large, contiguous area that contained many ecosystems where you could live. This enabled gene flow among many elephant populations. But by 2015, human activities had so drastically fragmented the total suitable area for elephants that the largest patch of good habitat represented less than 7% of it.</p>
<p>Sri Lanka and peninsular Malaysia have a disproportionately high share of Asia’s wild elephant population, relative to available elephant habitat area. Thailand and Myanmar have smaller populations relative to area. Interestingly, the latter are countries known for their large captive or semi-captive elephant populations.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1649084703272517636"}"></div></p>
<p>Less than half of the areas that contain wild elephants today have adequate habitat for them. Elephants’ resulting use of increasingly human-dominated landscapes leads to <a href="https://www.frontiersin.org/research-topics/25165/human-elephant-conflict-and-coexistence-in-asia">confrontations that are harmful</a> for both elephants and people. </p>
<p>However, this long view of history reminds us that protected areas alone are not the answer, since they simply <a href="https://doi.org/10.1038/s41598-022-22989-1">cannot be large enough</a> to support elephant populations. Indeed, human societies have <a href="https://doi.org/10.1073/pnas.2023483118">shaped these very landscapes for millennia</a>. </p>
<p>Today there is a pressing challenge to balance human subsistence and livelihood requirements with the needs of wildlife. Restoring <a href="https://doi.org/10.1002/gch2.202200051">traditional forms of land management</a> and <a href="https://doi.org/10.1038/s41893-021-00815-2">local stewardship</a> of these landscapes can be an essential part of protecting and recovering ecosystems that serve both people and wildlife in the future.</p><img src="https://counter.theconversation.com/content/202920/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Shermin de Silva receives funding from the US Fish & Wildlife Asian Elephant Conservation Funds. She is president and founder of Trunks & Leaves Inc. a non-profit organization that works to facilitate evidence-based conservation of Asian elephants and their habitats. de Silva also directs the Udawalawe Elephant Research Project in Sri Lanka, which she initiated in 2005, and is a member of the Asian Elephant Specialist Group of the IUCN Species Survival Commission. </span></em></p>A new study looks back into history to assess human impacts on the range of Asian elephants and finds sharp decline starting several centuries ago.Shermin de Silva, Assistant Professor of Ecology, Behavior and Evolution, University of California, San DiegoLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2001552023-02-22T22:06:37Z2023-02-22T22:06:37ZGood or bad? Some ‘invasive species’ can help native ecosystems thrive<figure><img src="https://images.theconversation.com/files/511584/original/file-20230222-16-84e4k9.jpg?ixlib=rb-1.1.0&rect=34%2C34%2C4566%2C3414&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A native Woodland Skipper butterfly sips nectar from a non-native Bull's Thistle flower.</span> <span class="attribution"><span class="source">Stephanie A. Rivest</span>, <span class="license">Author provided</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/good-or-bad-some--invasive-species--can-help-native-ecosystems-thrive" width="100%" height="400"></iframe>
<p>Whether or not invasive species threaten native biodiversity and ecosystems has been a point of debate amongst researchers for years. </p>
<p>Invasive species have caused <a href="https://doi.org/10.1016/j.tree.2005.01.003">extinctions of native species</a> and even <a href="https://doi.org/10.1007/s10021-002-0151-3">altered the functioning of ecosystems</a>. But not all species that are introduced to new areas become invasive — meaning they cause negative impacts.</p>
<p>Despite this, all <a href="https://doi.org/10.1016/j.tree.2022.08.005">non-native species are tagged as harmful</a>. This way of thinking has caused conservation management actions to typically focus on the eradication of non-native species with the goal of restoring “natural” landscapes. It has led scientific research to focus on identifying the negative consequences of non-native species. And it has stripped these species of their role as <a href="https://www.cbd.int/doc/decisions/cop-10/cop-10-dec-02-en.pdf">biodiversity indicators</a> used to describe the state of the environment.</p>
<p>Collectively, this has perpetuated the idea that native species are good and non-native species are bad. But what if we’re wrong about non-native species?</p>
<h2>Some non-native species do good</h2>
<p>While we should continue to be wary of non-native species, particularly those that have overwhelmingly negative impacts, the reality is that the role of most non-native species in ecological communities is uncertain or complex. </p>
<p>Some non-native species are a <a href="https://doi.org/10.1016/j.tree.2005.01.003">leading cause of species extinctions</a> whereas others contribute to <a href="https://doi.org/10.1016/S0169-5347(03)00224-6">regional biodiversity</a>. </p>
<p>Increasingly, scientists are reporting examples of positive roles that non-native species play such as providing food to native species, creating habitats or playing a role in ecosystem restoration. For example, <a href="http://dx.doi.org/10.1002/ecy.4004">native butterflies in Vancouver Island’s endangered Garry Oak savanna ecosystem</a> were found using non-native flowers for nectar, particularly in late summer when <a href="https://doi.org/10.1007/s00442-020-04785-8">native flowers are scarce</a>. </p>
<figure class="align-center ">
<img alt="A bird seen through large blades of grass in a marsh" src="https://images.theconversation.com/files/511588/original/file-20230222-14-4ylne.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/511588/original/file-20230222-14-4ylne.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=535&fit=crop&dpr=1 600w, https://images.theconversation.com/files/511588/original/file-20230222-14-4ylne.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=535&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/511588/original/file-20230222-14-4ylne.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=535&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/511588/original/file-20230222-14-4ylne.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=672&fit=crop&dpr=1 754w, https://images.theconversation.com/files/511588/original/file-20230222-14-4ylne.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=672&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/511588/original/file-20230222-14-4ylne.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=672&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Today, California’s ridgeway rail species partly relies on non-native cordgrass to escape predators and build nests.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/dagberg/39890003673/in/photolist-23LWGm2-2eoQWkE-242tUaL-PRRVAy-GppUyG-GppULq-DCaFgH-DbM2oH-242mnwq-HayBJ7-TdB414-2iccejL-F2ndEX-J9C3vz-ZVztvN-X6aai1-JsWpZ9-245oiwt-284UTkf-KfP8N2-93XYqj-zABhqB-PRRVtE-MC8o6y-4c3E23-qcKk7u-aLgGFg-Dtfo2q-CaYZD3-rhZnj3-2iubv3t-24biaCC-J6r2yL-HzSaAk-Jpexnv-YVA4cS-M7G8o4-FDNFVy-WK8rNL-QE7rjy-Jw2PK6-J6rKx5-MFHbft-MvDZUw-MFHaL2-2516HKR-pdeSjg-FdTq2o-EscSog-FdTpqU">(Doug Greenberg/flickr)</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<p>A more complex example is the case of the <a href="https://www.allaboutbirds.org/guide/Ridgways_Rail/overview#:%7E:text=">California ridgeway rail</a>, an endangered bird native to the marsh habitats in the San Francisco Bay area. Since the beginning of the 19th century, this species has been declining dramatically primarily because of the destruction of marsh habitats for agriculture and urban development. </p>
<p>Today, <a href="http://dx.doi.org/10.1007/s10530-013-0634-5">this bird relies, in part, on non-native salt-water cordgrass</a>, introduced to California in the 1970s, to escape from predators and build nests. The non-native cordgrass enhances habitats for the birds by providing more tall plant cover and increasing the area of marsh habitat. Efforts to eradicate the cordgrass throughout the 2000s led to declines in the Rail’s population size, demonstrating how a non-native species could be used to restore habitats and <a href="https://doi.org/10.5751/ES-08134-210119">support some native species</a>. </p>
<p>However, the cordgrass also converts mudflats into tidal wetlands, negatively impacting shorebirds that need mudflat habitats for foraging. Today, management efforts balance smaller removals of the cordgrass with monitoring of the Rails.</p>
<h2>Managing non-native species</h2>
<p>As ecologists researching non-native species for over 10 years, we believe that the negative perception of non-native species and the one-sided aggressive approach to their management may be leading scientists, conservation practitioners and policymakers to underestimate the positive roles that these species can play in ecological communities. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1320794877412679681"}"></div></p>
<p>Controlling non-native species is <a href="https://doi.org/10.1016/j.ecolecon.2004.10.002">expensive</a>, time-consuming and can be <a href="https://doi.org/10.1007/s11852-018-0635-8">ineffective in the long term</a>. Spending money, time and effort eradicating non-native species that have neutral or positive effects on native species is wasteful as those limited resources could be put to better use. </p>
<p>In some regions and cities, non-native species make up <a href="https://doi.org/10.1371/journal.pbio.2005568">more than half of all species</a>. Imagine the effort that would be needed to control all of the non-native species in these locations.</p>
<p>We need to re-think the idea that all non-native species are harmful. We need to evaluate the full range of impacts of non-native species before taking action against them. And eradication efforts should be reserved for situations where they will have the greatest benefits.</p>
<h2>Science shows the way</h2>
<p>We suggest two ways through which science can help move us forward.</p>
<p>First, rigorous biological research can help prioritize which non-native species should be removed and which can be left undisturbed. In cases where non-native species need to be removed, such studies can also tell us when additional management will be needed to support the existing native community. </p>
<figure class="align-center ">
<img alt="A savanna ecosystem on Vancouver Island, B.C." src="https://images.theconversation.com/files/511583/original/file-20230222-26-3rwx9q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/511583/original/file-20230222-26-3rwx9q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/511583/original/file-20230222-26-3rwx9q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/511583/original/file-20230222-26-3rwx9q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/511583/original/file-20230222-26-3rwx9q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/511583/original/file-20230222-26-3rwx9q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/511583/original/file-20230222-26-3rwx9q.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">Native butterflies in Vancouver Island’s endangered Garry Oak savanna ecosystem rely on non-native flower species for nectar late in the summer when this picture was taken.</span>
<span class="attribution"><span class="source">(Stephanie A. Rivest)</span></span>
</figcaption>
</figure>
<p>In the Garry Oak ecosystem on Vancouver Island, non-native flowers that are highly visited by native butterflies could be left alone, whereas others that are not visited could be prioritized for removal. If all non-native flowers must be removed, then managers could plant native flowers to ensure butterflies and other pollinators are left with sufficient food resources.</p>
<p>Second, researching the net effects of non-native species in ecological communities can improve the effectiveness of our conservation strategies. We need more studies that explicitly consider both positive and negative impacts of the same non-native species. </p>
<p>We are not suggesting that we should abandon our efforts to mitigate serious problems caused by some non-native species, or that governments should stop trying to prevent potentially harmful species from entering their jurisdictions. </p>
<p>Rather, we urge conservation practitioners and policymakers to organize and prioritize the management of habitats around whether species are more beneficial or harmful to biodiversity.</p><img src="https://counter.theconversation.com/content/200155/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Stephanie A. Rivest receives funding from University of Ottawa. </span></em></p><p class="fine-print"><em><span>Heather Kharouba does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Conservation practitioners and policymakers must organize and prioritize the management of habitats around whether species are more beneficial or harmful to biodiversity.Heather Kharouba, Associate Professor of Ecology, L’Université d’Ottawa/University of OttawaStephanie A. Rivest, Researcher, Department of Biology, L’Université d’Ottawa/University of OttawaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1949202023-02-02T03:02:58Z2023-02-02T03:02:58ZWin-win: how solar farms can double as havens for our wildlife<figure><img src="https://images.theconversation.com/files/507735/original/file-20230201-18-mw16wc.jpg?ixlib=rb-1.1.0&rect=30%2C6%2C4067%2C2297&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Australia’s renewable energy transition has prompted the construction of dozens of large-scale solar farms. The boom helps reduce Australia’s reliance on fossil fuels, but requires large areas of land to be converted to host solar infrastructure. </p>
<p>Solar farms are mostly built in rural areas. This has raised <a href="https://www.abc.net.au/news/2022-03-23/solar-farms-conflict-with-agricutural-land-use-/100920184">concerns</a> about a potential decline in both agricultural production – as arable land is used for solar energy production – and wildlife habitat. </p>
<p>But there are ways to expand solar infrastructure so both nature and people win. We’ve already <a href="https://theconversation.com/farmers-shouldnt-have-to-compete-with-solar-companies-for-land-we-need-better-policies-so-everyone-can-benefit-173333">seen this</a> in so called “<a href="https://www.weforum.org/agenda/2022/07/agrivoltaic-farming-solar-energy/">agrivoltaics</a>”, where land under and around solar panels is used to <a href="https://www.mdpi.com/2071-1050/13/14/7846">grow crops</a> and graze livestock. But what about “<a href="https://onlinelibrary.wiley.com/doi/10.1111/aec.13289">conservoltaics</a>”, combing conservation and solar energy?</p>
<p>My new research examines whether solar farms could also be used to help conserve native species. I found solar panels can provide valuable habitat for wildlife – and potentially benefit both the land and farmers.</p>
<figure class="align-center ">
<img alt="sheep graze among solar panels" src="https://images.theconversation.com/files/507775/original/file-20230202-5481-nxfh9e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/507775/original/file-20230202-5481-nxfh9e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=325&fit=crop&dpr=1 600w, https://images.theconversation.com/files/507775/original/file-20230202-5481-nxfh9e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=325&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/507775/original/file-20230202-5481-nxfh9e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=325&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/507775/original/file-20230202-5481-nxfh9e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=409&fit=crop&dpr=1 754w, https://images.theconversation.com/files/507775/original/file-20230202-5481-nxfh9e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=409&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/507775/original/file-20230202-5481-nxfh9e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=409&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">‘Agrivoltaics’ involves combining solar generation with agriculture – but what about ‘conservoltaics’?</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>A new place to call home</h2>
<p>Our wild landscapes are diminishing and protected areas, such as national parks, cover only <a href="https://soe.dcceew.gov.au/land/graphs-maps-and-tables?keys=land+use">about 9%</a> of Australia. </p>
<p>Many agricultural landscapes have been cleared of trees to provide pasture for livestock. It means wildlife that rely on trees have lost vast tracts of habitat.</p>
<p>So we must find new places for wildlife to forage, rest, shelter and breed.</p>
<p>My work examines how solar parks on agricultural land can double as wildlife habitat. It involves surveys and trapping to identify what plants and animals occupy solar farms, how long they take to recolonise, and how we can promote even more biodiversity. </p>
<p>My new paper coins a new term for this dual land-use: conservoltaics. I highlight research from overseas into how solar parks can bring conservation benefits, and describe the research still needed.</p>
<p>Solar panels add three-dimensional structure and complexity to an environment. They can provide animals shelter from predators and the elements, much like <a href="https://www.frontiersin.org/articles/10.3389/fmars.2020.00282/full">artificial reefs</a> in lakes and oceans. They can also act as perch or nesting structures.</p>
<p>Solar infrastructure also creates a mosaic of sun and shade patches – and so <a href="https://www.sciencedirect.com/science/article/pii/S0038092X21008562">provide</a> many “micro-habitats” for plants and animals.</p>
<p><a href="https://helapco.gr/wp-content/uploads/Solar_Farms_Biodiversity_Study.pdf">Research</a> from Europe has shown large solar farms can enhance the diversity and abundance of plants, grasses, butterflies, bees and birds.</p>
<p>What’s more, vegetation between solar panel rows <a href="https://www.sciencedirect.com/science/article/pii/S1364032121003531?via=ihub#fig3">can also provide</a> travel corridors, nesting sites and shelter for wildlife.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-queensland-is-still-ground-zero-for-australian-deforestation-196644">Why Queensland is still ground zero for Australian deforestation</a>
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<img alt="butterfly on plant in front of solar panel" src="https://images.theconversation.com/files/507748/original/file-20230201-20-nxfh9e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/507748/original/file-20230201-20-nxfh9e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/507748/original/file-20230201-20-nxfh9e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/507748/original/file-20230201-20-nxfh9e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/507748/original/file-20230201-20-nxfh9e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/507748/original/file-20230201-20-nxfh9e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/507748/original/file-20230201-20-nxfh9e.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">Research shows solar arrays can increase the presence of pollinators such as butterflies.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Management is key</h2>
<p><a href="https://www.sciencedirect.com/science/article/pii/S1364032121003531?via=ihub#fig3">Research suggests</a> several management strategies that can maximise the benefits of solar farms for wildlife. </p>
<p>Land managers should provide a diverse mix of flowering plant species to encourage pollinators. And grass between solar panels should not be mowed too short or too often. Pollinators prefer tall vegetation where they can forage – though vegetation should not be so tall that it shades the solar panels.</p>
<p>The use of herbicides and other chemicals should be avoided where possible. And solar farms should be connected to other vegetated areas, using features such as hedgerows and wildflower strips, so wildlife can move between the solar farm and other habitats.</p>
<p>Landholders who combine solar farms with wildlife habitat may reap several benefits.</p>
<p>They could receive financial returns by earning environmental credits through schemes that reward carbon sequestration and biodiversity improvements. </p>
<p>They may also improve the health of their land by, for example, increasing pollination or providing habitat for predators such as raptor perches or nest boxes – which in turn could help control pests.</p>
<p>Much work remains, however, to understand these opportunities. </p>
<figure class="align-center ">
<img alt="small frog on human hand in front of solar panels" src="https://images.theconversation.com/files/507749/original/file-20230201-20-eoke8k.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/507749/original/file-20230201-20-eoke8k.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/507749/original/file-20230201-20-eoke8k.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/507749/original/file-20230201-20-eoke8k.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/507749/original/file-20230201-20-eoke8k.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/507749/original/file-20230201-20-eoke8k.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/507749/original/file-20230201-20-eoke8k.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Farm management strategies can maximise the benefits of solar farms for wildlife.</span>
<span class="attribution"><span class="source">Eric Nordberg</span></span>
</figcaption>
</figure>
<h2>Looking ahead</h2>
<p>The benefit of renewable energy in reducing carbon emissions is well known. But more work is needed to understand how solar farms can benefit wildlife.</p>
<p>Research is also lacking on how to locate, configure and manage solar farms to best enhance biodiversity. Collaboration between industry, land managers and researchers is needed so clean energy production and conservation can go hand-in-hand.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/australia-needs-much-more-solar-and-wind-power-but-where-are-the-best-sites-we-mapped-them-all-196033">Australia needs much more solar and wind power, but where are the best sites? We mapped them all</a>
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</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/194920/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Eric Nordberg does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Solar panels can provide places for animals to rest, shelter and breed – potentially benefitting both the land and farmers.Eric Nordberg, Senior Lecturer (Applied Ecology and Landscape Management), University of New EnglandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1966792023-01-11T06:12:34Z2023-01-11T06:12:34ZMountain environments are key to biodiversity – but the threats to them are being ignored<figure><img src="https://images.theconversation.com/files/503025/original/file-20230104-19747-ka27f3.jpg?ixlib=rb-1.1.0&rect=20%2C0%2C6693%2C3764&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Mountains are home to a diverse range of plant and animal species.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/mountain-peaks-torres-del-paine-patagonia-1931671382">JMP_Traveler/Shutterstock</a></span></figcaption></figure><p>Mountains are home to <a href="https://www.science.org/doi/10.1126/science.aax0149">more than 85%</a> of the world’s amphibian, bird and mammal species. Lowland slopes are rich in animal and plant species. And rugged, high-elevation environments, although lacking such biological diversity, play a key role in maintaining biodiversity in the wider mountain catchment area.</p>
<p>The variation in mountain ecosystems also allows humans to extract <a href="https://doi.org/10.1017/S0376892918000255">multiple benefits</a> from them. These include food, building materials, water, carbon storage, agricultural pasture and nutrient cycling.</p>
<p>Yet, vulnerable to both climate change and human intervention, mountain biodiversity is increasingly under threat. <a href="https://www.science.org/doi/10.1126/science.aax0149">Roughly half</a> of the world’s <a href="https://www.conservation.org/priorities/biodiversity-hotspots">biodiversity hotspots</a> are now located in mountainous regions. These are areas of the Earth with significant levels of biodiversity but threatened to the extent that up to 70% of the original habitat has been lost. </p>
<p>And high mountain environments are <a href="https://www.nature.com/articles/nclimate2563">warming faster</a> than the global average. This is accelerating the rate of change in these ecosystems.</p>
<p>Despite this, mountains are largely ignored by attempts to preserve global biodiversity. </p>
<h2>The importance of mountains</h2>
<p>High mountains receive a lot of rain and experience low rates of evaporation at high elevations. They therefore contain large stores of water as snow and ice which are the foundation for biodiversity in the surrounding catchment. </p>
<p>Seasonal snow melt on Africa’s Mount Kilimanjaro feeds into the swamps of the nearby <a href="http://www.kws.go.ke/amboseli-national-park">Amboseli National Park</a>. The park is home to 420 species of bird and 50 large mammal species, including the African elephant.</p>
<p>Due to their steep elevation gradients, mountain environments also consist of many separate habitats. In temperate latitudes, such as Europe and North America, these habitats range from coniferous forests at low elevations to rugged terrain on higher ground. Habitats in tropical mountains instead range from savannas and lowland rainforests to highland <a href="https://www.frontiersin.org/articles/10.3389/fpls.2021.712748/full">“montane” forest</a> at an elevation of 900 metres to 3,300 metres. </p>
<p>Such habitat diversity supports a wide range of plant and animal species across relatively small spatial scales. Borneo’s lowland rainforests are home to <a href="https://www.oneearth.org/ecoregions/borneo-lowland-rainforests/#:%7E:text=Borneo%20rainforests%20are%20multi%2Dlayered,Vatica%2C%20Burseraceae%2C%20and%20Sapotaceae.">over 15,000 plant species</a> while <a href="https://wwf.panda.org/discover/knowledge_hub/where_we_work/borneo_forests/about_borneo_forests/ecosystems/montane_forests/">over 150 mammal species</a>, including orangutans and gibbons, live in Borneo’s montane forests. </p>
<p>Much of this biodiversity is also exclusive to particular mountain environments. Many mountain ecosystems are islands of suitable and isolated habitat. As a result, they are often home to species characterised by small populations and a limited range.</p>
<p>The <a href="https://ebird.org/species/taithr1">Taita thrush</a>, for example, is confined to the forests of southeast Kenya’s Taita Hills. Here, the species is surrounded by arid savanna within which it could not survive.</p>
<figure class="align-center ">
<img alt="A Taita trush perched on a branch." src="https://images.theconversation.com/files/503067/original/file-20230104-14-uocmr0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/503067/original/file-20230104-14-uocmr0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=488&fit=crop&dpr=1 600w, https://images.theconversation.com/files/503067/original/file-20230104-14-uocmr0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=488&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/503067/original/file-20230104-14-uocmr0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=488&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/503067/original/file-20230104-14-uocmr0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=613&fit=crop&dpr=1 754w, https://images.theconversation.com/files/503067/original/file-20230104-14-uocmr0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=613&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/503067/original/file-20230104-14-uocmr0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=613&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Taita thrush is endemic to southeast Kenya’s Taita Hills.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/taita-thrush-ebird-ethiopia-addis-ababa-2222653291">Mounir akaram halabi/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Vulnerable ecosystems</h2>
<p>Snow reflects much of the incoming solar radiation back out to space. But climate change is increasing rates of snow melt, exposing large areas of dark mountain surface to the sun. This is leading to rising solar absorption rates and significant warming. </p>
<p><a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015JD024728">Research</a> reveals that the Tibetan plateau (often called the third pole) has warmed by 0.16°C–0.36°C per decade on average since the 1950s. But this decadal rate of warming has increased to 0.5°C–0.67°C since the 1980s. </p>
<p>Increased warming in mountain environments will further amplify snow melt and reduce snow accumulation. Less snow and ice will result in a reduced availability of water downstream in the future, affecting the functioning of habitats in the mountain catchment. </p>
<p>Mountain environments are also vulnerable to human intervention. Mount Kilimanjaro’s fertile volcanic soil has encouraged human habitation of the surrounding area throughout history. But in recent decades, this has accelerated. </p>
<p>For example, agricultural land use in the Upper Pangani catchment to Kilimanjaro’s south <a href="https://www.sciencedirect.com/science/article/abs/pii/S1642359322000489">expanded</a> from 97,000 hectares in 1987 to over 300,000 hectares by 2017. The amount of groundwater collecting in the mountain’s aquifer decreased by 6.5% over the same period.</p>
<p>Land use change in mountain environments is leading to significant biodiversity loss. The Eastern Arc mountains of Kenya and Tanzania have lost <a href="https://link.springer.com/book/10.1007/978-3-030-88987-6">95% of their forest cover</a> since 1500, reducing the diversity of unique flora and fauna that are found in the area. The <a href="https://www.amphibians.org/amazing-amphibians/kihansi-spray-toad/">Kihansi spray toad</a>, for example, is now extinct in the wild. </p>
<h2>Ignoring mountains</h2>
<p>Yet while it’s clear mountains are important for the ecosystems they support, recognition of these environments from governments and policymakers is insufficient. There is currently no effective international policy in place to protect the biodiversity of mountain environments and there is little cooperation between governments, environmental agencies and conservationists to deliver such a strategy.</p>
<p>Establishing a cost for the services provided by mountain ecosystems would be a step towards reducing their exploitation. </p>
<p>Management of rivers with variable stream flows can be achieved by issuing controllable permits for water use. <a href="https://www.sciencedirect.com/science/article/abs/pii/S0022169419311345?via%3Dihub">Water market reform</a> in southeastern Australia’s Murray-Darling river basin is a successful example. Landowners and businesses here are able to purchase tradeable water entitlements set to levels that do not compromise the environment. </p>
<p>Since its introduction 30 years ago, this system has improved water quality and has allowed more water to be retained in the river basin. The expanding wetlands are also proving a <a href="https://www.sciencedirect.com/science/article/pii/B9780128181522000103">successful nursery habitat</a> for the native Murray cod and silver perch fish species.</p>
<figure class="align-center ">
<img alt="An aerial shot of a river lined with trees." src="https://images.theconversation.com/files/503460/original/file-20230106-25-u0sftr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/503460/original/file-20230106-25-u0sftr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/503460/original/file-20230106-25-u0sftr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/503460/original/file-20230106-25-u0sftr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/503460/original/file-20230106-25-u0sftr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/503460/original/file-20230106-25-u0sftr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/503460/original/file-20230106-25-u0sftr.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">The Murray-Darling river basin in southeastern Australia.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/aerial-view-murray-darling-junction-flood-594574802">Hypervision Creative/Shutterstock</a></span>
</figcaption>
</figure>
<p>But schemes such as this are open to regulatory challenges and issues over who manages the resource. <a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2020WR028378">Unreliable and inaccurate data</a> on agricultural water and groundwater abstraction also constrains global water management. </p>
<p>Both the recent <a href="https://theconversation.com/cop27-will-be-remembered-as-a-failure-heres-what-went-wrong-194982">UN climate change summit (COP27)</a> and <a href="https://theconversation.com/biodiversity-treaty-un-deal-fails-to-address-the-root-causes-of-natures-destruction-196905">UN biodiversity conference (COP15)</a> ended short of ambition over protecting mountain biodiversity. A series of agreements and targets were established with little disclosure over how they will be financed and enforced. An international treaty that accepts the value of mountain ecosystems and puts measures in place to protect their environmental, economic and biological importance is urgently required.</p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
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<p class="fine-print"><em><span>Rob Marchant receives funding from a number of grant-giving organisations for this work including UKRI, the Royal Society, the European Union and SIDA.</span></em></p>Mountain environments are rich in plant and animal species, but the dual threat of human habitation and climate change means urgent action is needed to protect them.Rob Marchant, Professor of Tropical Ecology, University of YorkLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1941932022-12-14T19:03:32Z2022-12-14T19:03:32ZWhy humans walk on two legs: a close look at chimpanzees puts some old theories to the test<figure><img src="https://images.theconversation.com/files/494461/original/file-20221109-11066-rc0uqn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Issa chimpanzees live in a woodland dominated environment interspersed with riparian forests, grasslands, and rocky out-crops.</span> <span class="attribution"><span class="source">Photo: R. Drummond-Clarke/GMERC</span></span></figcaption></figure><p>There’s no trait that distinguishes humans from all other mammals more clearly than the way we walk. Human habitual bipedalism – obligatory walking on two legs – has long been a defining trait of our species, as well as our <a href="https://www.pnas.org/doi/epdf/10.1073/pnas.1403659111">ancestors</a> as far back as 4.5 million years ago. </p>
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<p>Science’s growing understanding of chimpanzee <a href="https://www.sciencedirect.com/user/identity/landing?code=BvsF9eoluiU4PM_ggq_BzJQI_X1w3TYEkicwlleS&state=retryCounter%3D0%26csrfToken%3D15935e62-4880-4120-b3d0-6bb49e549aff%26idpPolicy%3Durn%253Acom%253Aelsevier%253Aidp%253Apolicy%253Aproduct%253Ainst_assoc%26returnUrl%3D%252Fscience%252Farticle%252Fpii%252FS0003347217304190%253Fcasa_token%253DqVoj9ufZbcMAAAAA%253AhcJ8zDmjghQ1kChZJabBl7nx3qGIAPvifk0mXaNdWe5bLP9jVeRwW0aYK16PqKUl-lcH9f_tWg%26prompt%3Dnone%26cid%3Darp-2498874e-3b20-4793-977f-25ad0d95aa49">culture</a>, communication and <a href="https://www.tandfonline.com/doi/full/10.1080/03949370.2022.2044390?casa_token=elxIS7F_x4sAAAAA%3AwB4IuVnWfxzrKePJ9cE4QhBImDX7CM_9xbumEWGJ-lS-5GbAKNAh1DC1IXvoFB6k9Te23N1vM1NW">emotion</a> may have blurred the understanding of “distinctly human”, but our obligatory bipedalism has stood the test of time. </p>
<p>Why, when, and where bipedalism evolved remains debated, however. Numerous evolutionary pressures have been proposed. Most are about the economics and <a href="https://www.pnas.org/doi/abs/10.1073/pnas.0703267104">energy use</a> of walking on two legs (bipedalism is far more efficient than quadrupedalism). Other theories describe the advantages of <a href="https://www.cell.com/fulltext/S0960-9822(12)00082-6">carrying objects</a>. Bipedalism frees the hands to do interesting things like make and use tools and reach for fruit. It also enables us to see over tall grass.</p>
<p>But almost all the theories suggest that bipedalism is an adaptation to getting around on land. It’s clear that early bipeds evolved when <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/j.1365-2745.2007.01323.x">savanna grasslands</a> became increasingly common as forests retreated 4-8 million years ago. Walking on two legs made it easier to forage and travel on the ground. </p>
<p>But there’s also evidence that contradicts this idea. Hominin anatomy, palaeo-ecology and the behaviour of some ape species present challenges to the theory. For example, early hominins had a long list of <a href="https://www.science.org/doi/full/10.1126/sciadv.abf2474">adaptations</a> to life in the trees. These included long limbs, mobile shoulders and wrists, and curved fingers. All these features are present in our current tree-dwelling primate cousins. </p>
<p>Studies of what <a href="https://www.sciencedirect.com/science/article/pii/S0047248418302902?casa_token=zpa8_BZQXvAAAAAA:c-tr7PRhAWte_RzlQnyDGdILAd04q0V9ezzraZWCt2-TWYBzxWX8y0SZq3vDgG9goRFENvcjvQ">hominins ate</a> and the animals they lived with (bushbucks, colobus monkeys) also suggest that these hominins did not live in grasslands. Instead, they inhabited mosaic landscapes, consisting most likely of a mixture of riparian forests and woodlands. </p>
<p>Finally, evidence from the only non-African great ape – the orangutan – suggests bipedalism was an <a href="https://www.science.org/doi/10.1126/science.1140799?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%20%200pubmed">adaptation to living in trees</a>. It helped the apes to negotiate flexible branches high in the tropical rainforests of southeast Asia.</p>
<p>To further test hypotheses about how hominins may have foraged and moved in a mosaic habitat – and whether this habitat pushed them to evolve towards living on the ground and walking on two legs – <a href="http://www.science.org/doi/10.1126/sciadv.add9752">we investigated</a> the behaviour of wild chimpanzees in a savanna mosaic in the Issa valley in Tanzania. </p>
<h2>Issa chimpanzees</h2>
<p>Issa chimpanzees live in an environment dominated by woodland. It is interspersed with grasslands, rocky outcrops and forests alongside streams. We followed chimpanzees for 15 months, collecting data every two minutes on an individual’s positional behaviour, the vegetation type they were in (forest, woodland), and what they were doing (foraging, resting, grooming and so on).<br>
We expected that chimpanzees would spend more time on the ground and standing or moving upright in open vegetation like woodlands where they cannot easily travel via the tree canopy. We thought they would be more terrestrial overall compared with their forest-dwelling cousins in other parts of Africa.</p>
<p><a href="http://www.science.org/doi/10.1126/sciadv.add9752">We found</a> that Issa chimpanzees do indeed spend more time on the ground in woodlands than in forests. But they were not more terrestrial than other (forested) communities. In short, it is not a simple rule of fewer trees leads to more time on the ground. </p>
<p>It’s not clear why Issa chimpanzees spent so little time on the ground. It could be that they spend more time within feeding trees due to <a href="https://www.nature.com/articles/s42003-018-0115-6">tougher foods</a> that may take longer to process than those found in the forests. Alternatively, they could be staying out of the reach of Issa’s many predators, including wild dogs, hyenas, and lions. We don’t yet know what is driving Issa chimpanzees into the trees.</p>
<p>Our findings also suggest a decoupling between terrestial activity and bipedalism. Over 85% of bipedal events were when chimpanzees were in trees (mostly feeding), not on the ground, similar to what was described for orangutans.</p>
<p>Our data from Issa do not support the view that bipedalism evolved as a terrestrial behaviour, especially in more open habitats.</p>
<h2>Why it matters</h2>
<p>Our study represents the first test in a living ape of the long-held hypothesis that cool, dry and open environments during a critical junction in human evolution catalysed the evolution of terrestrial bipedalism.</p>
<p>Issa allows us to study ape-habitat interactions as they might have been millions of years ago. Hominins may not have responded to a mosaic landscape in exactly the same way as today’s chimpanzees do. But the way savanna chimpanzees move around and hold their bodies supports the idea that early hominin bipedalism evolved in the trees, not on the ground.</p><img src="https://counter.theconversation.com/content/194193/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>Almost all theories of human bipedalism explain it as a terrestrial adaptation. A new study does not support that view.Fiona Stewart, Lecturer in Wildlife Conservation, Liverpool John Moores UniversityAlexander Piel, Asso. Professor in Anthropology, University College London, UCLLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1885042022-11-03T12:00:39Z2022-11-03T12:00:39ZOlive ridley sea turtles are constantly on the move, so protective zones should follow them<figure><img src="https://images.theconversation.com/files/492819/original/file-20221101-25187-w4klf3.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C7090%2C4732&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An olive ridley swims Into the wild blue yonder.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/a-olive-ridleys-turtle-swimming-below-the-surface-royalty-free-image/524867607">Gerard Soury/The Image Bank via Getty Images</a></span></figcaption></figure><p>Many of the ocean’s most charismatic animals spend their lives swimming, flying or gliding thousands of miles, from the coasts to the high seas. Arctic terns, humpback whales and sea turtles are examples. Scientists have spent many years documenting and studying these magnificent journeys. </p>
<p>Chronicling where these species go is just the beginning. The next steps are understanding when and how far each animal travels and what triggers it to roam. </p>
<p>We are a <a href="https://scholar.google.com/citations?user=BQNRM-8AAAAJ&hl=en">marine biologist</a> and an <a href="https://scholar.google.com/citations?user=4vqRTOAAAAAJ&hl=en">evolutionary ecologist</a> and have worked together to study the nesting and migration habits of <a href="https://ecos.fws.gov/ecp/species/1513#v">endangered olive ridley sea turtles</a> (<em>Lepidochelys</em> <em>olivacea</em>). This information is vital for managing the turtles’ recovery – but our research shows that two identical-looking olive ridleys may follow very different paths. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/492817/original/file-20221101-23-ma4us.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="World map with tropical oceans highlighted" src="https://images.theconversation.com/files/492817/original/file-20221101-23-ma4us.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492817/original/file-20221101-23-ma4us.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=304&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492817/original/file-20221101-23-ma4us.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=304&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492817/original/file-20221101-23-ma4us.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=304&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492817/original/file-20221101-23-ma4us.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=382&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492817/original/file-20221101-23-ma4us.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=382&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492817/original/file-20221101-23-ma4us.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=382&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Approximate range of olive ridley sea turtles.</span>
<span class="attribution"><a class="source" href="https://www.fisheries.noaa.gov/species/olive-ridley-turtle">NOAA</a></span>
</figcaption>
</figure>
<h2>Protecting animals that move</h2>
<p>Mapping the spatial distribution and movement patterns of marine animals that are endangered or threatened is essential for defining <a href="https://www.fisheries.noaa.gov/national/endangered-species-conservation/critical-habitat">critical habitat</a> – areas that these species need in order to recover, such as key breeding or feeding grounds.</p>
<p>Once scientists identify critical habitats, governments can integrate them into <a href="https://marineprotectedareas.noaa.gov/aboutmpas/">marine protected areas</a>. These typically are defined zones with fixed borders. They benefit marine animals that stay in one place, like sea anemones; have small ranges; and require specific habitats, such as coral reefs or seagrass beds. </p>
<p>But highly migratory marine animals have large ranges and can travel many miles per day. They may prefer a certain location one year and a different one the next year. And their movements are driven by shifting ocean circulation patterns. Marine protected areas <a href="https://theconversation.com/to-conserve-ocean-life-marine-reserves-need-to-protect-species-that-move-around-89907">are not effective</a> for protecting highly mobile species – and olive ridley sea turtles are incredibly mobile. </p>
<h2>Ocean nomads</h2>
<p>Olive ridleys are among the smallest of the world’s sea turtles and are found in the tropical Atlantic, Pacific and Indian oceans. They are best known for their signature <a href="https://www.fisheries.noaa.gov/species/olive-ridley-turtle">synchronized mass nestings on beaches</a> in early summer, which are called arribadas – Spanish for “arrival.”</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/-SkqLta93Ys?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Thousands of female olive ridley sea turtles nest in an arribada in Costa Rica.</span></figcaption>
</figure>
<p>Fishing in the eastern Pacific Ocean decimated nesting colonies of olive ridleys before commercial exploitation ended in the 1980s. The species has begun to recover but remains <a href="https://www.iucnredlist.org/species/11534/3292503">listed as vulnerable</a> by the <a href="https://www.iucn.org/">International Union for the Conservation of Nature</a>. The U.S. <a href="https://ecos.fws.gov/ecp/species/1513">classifies olive ridleys as threatened</a>, except for a group that nests on Mexico’s Pacific coast that is classified as endangered. <a href="https://www.fisheries.noaa.gov/species/olive-ridley-turtle#">Threats</a> include fishing, hunting of eggs and turtles on nesting beaches, coastal development, boat collisions and water pollution.</p>
<p>One of us, Pamela Plotkin, began studying olive ridleys in 1990, when satellite telemetry first emerged as a viable tool for following them at sea. Initially, Plotkin expected to document groups of turtles migrating from their mass nesting beach in Costa Rica to an undiscovered feeding ground in the eastern Pacific Ocean, far from land. </p>
<p>Adult female sea turtles typically have a predetermined endpoint where they go to feed after they finish nesting on beaches. It was easy to imagine throngs of turtles migrating in “turtle schools” between the beach and their feeding ground. </p>
<p>Plotkin envisioned creating a simple conservation plan to protect the migratory corridor linking these two critical habitats. But she <a href="https://doi.org/10.1007/BF00349287">found nothing of the sort</a>.</p>
<p>Instead, she learned, <a href="http://dx.doi.org/10.3354/esr00314">olive ridleys’ journey has no endpoint</a>. They swim hundreds to thousands of miles from their nesting beach, moving continuously among multiple areas, following unpredictable and widely dispersed pathways that vary year to year. </p>
<p>Clearly, there was a need to better define critical habitat for this highly mobile turtle in a huge expanse of ocean. </p>
<h2>Searching for the sweet spot</h2>
<p>In 2015, with the addition of doctoral student <a href="https://www.seaturtlebiologist.com/">Christine Figgener</a>, our research group picked up where prior studies had left off. Part of Figgener’s dissertation research focused on characterizing critical habitat for olive ridleys in the eastern Pacific Ocean and understanding their habitat preference based on <a href="https://doi.org/10.3389/fevo.2022.933424">changing environmental variables</a>. They included sea surface temperature and concentrations of chlorophyll-a, which is found in marine algae, an essential food source for the diverse plankton that <a href="https://doi.org/10.3389/fmars.2017.00348">olive ridleys eat</a>.</p>
<p>Figgener captured olive ridleys from multiple beaches in Costa Rica, including turtles that nested alone rather than in large groups. She glued satellite trackers to 23 turtles’ shells and followed them from their nesting beaches. We also acquired satellite data on conditions including sea surface temperature, chlorophyll-a concentrations and how deeply sunlight penetrated into the upper ocean in areas where the turtles traveled. </p>
<p>By combining old and new data, with a total of 43 different migration tracks and 1,553 in-water turtle locations, we identified high-use areas for olive ridleys between Mexico and Peru and developed a habitat preference model to understand what attracts turtles to specific areas. </p>
<h2>Predictably unpredictable</h2>
<p>The female olive ridleys that we tracked swam long distances north, west and south from Costa Rica. Their routes did not overlap, and their movements did not reveal any well-defined migratory corridor of the kind that many species follow. </p>
<p>We mapped the areas where these nomads clustered, and found that their high-use areas spanned the exclusive economic zones – areas extending up to 200 miles offshore – of six countries: <a href="https://doi.org/10.3389/fevo.2022.933424">Mexico, Guatemala, El Salvador, Nicaragua, Costa Rica and Panama</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/492818/original/file-20221101-26-j9prao.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map showing olive ridley distribution in the eastern Pacific" src="https://images.theconversation.com/files/492818/original/file-20221101-26-j9prao.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492818/original/file-20221101-26-j9prao.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=804&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492818/original/file-20221101-26-j9prao.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=804&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492818/original/file-20221101-26-j9prao.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=804&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492818/original/file-20221101-26-j9prao.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1011&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492818/original/file-20221101-26-j9prao.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1011&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492818/original/file-20221101-26-j9prao.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1011&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">These images show olive ridley high-use areas in the eastern Pacific. Black dots are satellite tracker locations. Important areas are yellow (figure A), critical areas are red (figures A and B), and exclusive economic zones are marked by yellow lines (figure B).</span>
<span class="attribution"><a class="source" href="https://www.frontiersin.org/files/Articles/933424/fevo-10-933424-HTML-r1/image_m/fevo-10-933424-g002.jpg">Figgener et al., 2022.</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>When we compared high-use areas for mass nesting turtles with those of solitary nesting turtles, we saw striking differences. Mass-nesting turtles clustered into one large, connected area that was smaller and closer to the coastline. Solitary nesting turtles’ high-use areas were disconnected, widely dispersed and farther from the coast. </p>
<p>Our model indicated that the turtles preferred habitat where the water was warmer than about 77 degrees Fahrenheit (25 degrees Celsius) and deeper than 13,000 feet (4,000 meters), and where phytoplankton were abundant. </p>
<h2>A conservation challenge</h2>
<p>Current conservation strategies for sea turtles typically emphasize <a href="https://doi.org/10.1371/journal.pbio.0060171">protecting static migratory corridors</a>. But this approach won’t benefit nomadic olive ridleys. Instead, these turtles’ wide-ranging migrations and shifting use of space require a <a href="https://doi.org/10.1093/biosci/biv018">dynamic ocean management</a> strategy. This approach uses real-time data to track target animals where they are and creates movable protected zones in a changing environment. </p>
<p>Dynamic management has been used successfully in developed countries to reduce threats to <a href="https://doi.org/10.1016/j.marpol.2015.03.014">whales, fish and sea turtles</a> from capture in fisheries and vessel strikes. It integrates many kinds of data, including satellite tracking, voluntary catch reports from fishermen and modeling of target species’ habitat preferences. Information is quickly shared via mobile apps so that, for example, ship captains are alerted to reduce vessel speed when whales are likely to be nearby. </p>
<p>Expanding this approach to developing countries poses a challenge, but is <a href="https://doi.org/10.1017/S0030605312000105">within reach</a>. A dynamic management system for olive ridleys would need to predict where the turtles are likely to be present in a perpetually changing environment, and address threats in these critical spaces. It also would require nations to work together to regulate fisheries that capture and threaten turtles in their territorial waters. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1515403902434562048"}"></div></p>
<p>Another important angle of our research is the contrast we found between habitat use by mass-nesting turtles and solitary-nesting turtles. It supports previous studies that found <a href="https://press.jhu.edu/books/title/9346/biology-and-conservation-ridley-sea-turtles">two distinct groups of turtles within the same population</a>. </p>
<p>Conservation efforts on nesting beaches have focused mainly on protecting a small number of beaches in Mexico and Costa Rica that olive ridleys use for mass nestings. But hundreds of solitary nesting beaches extending from Mexico to Ecuador are largely unprotected. These turtles <a href="https://www.iucnredlist.org/species/11534/3292503">have declined significantly in number in recent years</a>. We contend that conserving olive ridleys will require action both on land and at sea.</p><img src="https://counter.theconversation.com/content/188504/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Pamela T. Plotkin received funding from the National Science Foundation for a portion of the research described in this article. Doctoral student Christine Figgener received funding from multiple sources to support some of the research described in this article including the Lerner-Gray-Fund for Marine Research, Texas Sea Grant, and the George H. W. Bush Presidential Library Foundation </span></em></p><p class="fine-print"><em><span>Joseph Bernardo 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>Standard marine protected areas with fixed boundaries can’t effectively shelter these ocean nomads.Pamela T. Plotkin, Associate Research Professor and Director, Texas Sea Grant, Texas A&M UniversityJoseph Bernardo, Research Associate Professor of Biology, Texas A&M UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1877392022-09-26T16:36:59Z2022-09-26T16:36:59ZBeavers can do wonders for nature – but we should be realistic about these benefits extending to people<figure><img src="https://images.theconversation.com/files/481140/original/file-20220825-18-ekh1hx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The potential role of beavers in safeguarding against climate change risks has become an interesting point of discussion</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/close-eurasian-beaver-castor-fiber-rubbing-1075908656">RudiErnst/Shutterstock</a></span></figcaption></figure><p>The beaver is a unique ecosystem engineer that can create a landscape that would otherwise not exist, thanks to the animal’s ability to build dams. As we experience more frequent heatwaves and drought, the potential role of beavers in safeguarding against these risks has captured widespread attention. </p>
<p>Beaver habitats are <a href="https://www.vox.com/down-to-earth/23273240/heat-wave-beavers-climate-change">claimed</a> to lower local stream and air temperatures, and by <a href="https://www.independent.co.uk/climate-change/news/beavers-drought-heatwave-flood-national-trust-b2142302.html">maintaining water supplies</a>, provide insurance against drought. Greater water storage may also improve the resilience of a landscape towards <a href="https://www.theguardian.com/environment/2022/jul/21/beavers-to-be-given-legal-protection-in-england">wildfire</a>.</p>
<p>However, it is important to consider the significance of beaver habitats as a solution to our changing climate from both human and wildlife perspectives. It’s not as simple as saying beavers can protect human society against the effects of extreme weather.</p>
<h2>Water storage and wildlife sanctuary</h2>
<p>Beaver ponds and wetlands can cover wider areas and store more water than the stream that would flow without them. However, beavers are restricted to relatively small streams. </p>
<p>To achieve a <a href="https://www.sciencedirect.com/science/article/pii/S0048969716323099#s0045">water capacity</a> large enough to supplement human supplies, beavers would have to construct an unrealistically large number of ponds across the same catchment. Even then, the water storage would be dispersed across many shallow ponds, making extraction for use in a water supply network unrealistic. </p>
<p>What an increase in beaver ponds can do is provide more refuges for wildlife at a local level, while allowing the slow release of water downstream during dry periods. Such refuges can be <a href="https://www.theguardian.com/environment/2022/jul/25/falling-birds-and-dehydrated-hedgehogs-heatwave-takes-its-toll-on-wildlife-aoe">critical</a> for wildlife during a drought, and so help preserve an area’s biodiversity. </p>
<p>Greater water storage will also increase an ecosystem’s resilience to climate change. This has been demonstrated during this summer’s drought. Beaver wetlands in Devon’s <a href="https://www.independent.co.uk/climate-change/news/drought-heatwave-devon-beavers-photos-b2149993.html">River Otter</a> have irrigated the surrounding area and kept vegetation alive, preserving a habitat that many animals depend on.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1561398131358855168"}"></div></p>
<h2>Evaporative cooling</h2>
<p>Bodies of water can also reduce the air temperature surrounding them because their evaporation has a cooling effect. However, unless the water bodies are very large, or high in number, this easing tends to diminish rapidly with distance from the water. This would make it difficult to rely upon beaver ponds for cooling benefits for human settlements. </p>
<p>Beavers also tend to open up the canopies of nearby forests by felling trees during the construction of dams. This can reduce shading and allow more direct sun exposure, which complicates any potential cooling effects. </p>
<p>However, felling can also increase habitat complexity, supporting a mixture of meadows and wet woodland. The natural disturbance caused by beavers can create floodplain woodlands that are wilder and wetter, allowing <a href="https://www.sciencedirect.com/science/article/pii/S0167880921005260">greater biodiversity</a>. In some cases, this can also <a href="https://theconversation.com/beavers-are-back-heres-what-this-might-mean-for-the-uks-wild-spaces-166912">slow the flow of water and improve water quality</a>.</p>
<p>This same process of opening up the canopy can also increase local water temperatures. However, this can be heavily moderated by the <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/surface-water-groundwater-interaction">interaction</a> between surface water and groundwater. </p>
<p>This means the outcome for water temperatures will be highly river, dam, and pond dependent. For this reason, <a href="https://www.sciencedirect.com/science/article/pii/S0012825221001239">research</a> into the thermal impact of beaver habitats has proved inconclusive.</p>
<h2>Protection against wildfires</h2>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/IAM94B73bzE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Beaver habitats are uniquely resistant to disturbances such as droughts and fire.</span></figcaption>
</figure>
<p>Wildfires have been extensive across Europe this summer. <a href="https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/bes2.1795">Research</a> has shown how the preservation of beaver habitats can improve the fire-resistance of the landscape. </p>
<p>During wildfire, the area of vegetation density loss in beaver habitats was approximately <a href="https://esajournals.onlinelibrary.wiley.com/doi/10.1002/eap.2225">three times smaller</a> than in areas without beavers in the western USA. </p>
<p>However, questions remain as to whether this protection could ever expand to the scale necessary for human settlements. Even if this is not realistic, beaver habitats provide crucial protection for local habitat and wildlife against wildfire. </p>
<h2>Future of the Eurasian Beaver in England</h2>
<p>This summer has also brought new climate extremes and a prolonged period of drought. With more of this predicted, the debate surrounding mitigation measures is growing. Beavers enjoy enthusiastic support in this regard. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1551983541902360577"}"></div></p>
<p>However, it would be wise to temper expectations for the role of beavers as a drought solution for human settlements. Nevertheless, by offering a local buffer against the ravages of drought, heatwaves, and wildfire, beaver habitats carry the potential to help stimulate nature recovery and reverse biodiversity loss.</p>
<p>In the UK, beavers have recently received <a href="https://www.bbc.co.uk/news/science-environment-62213459">legal protection</a>, but face a future of expansion into human landscapes. The decades ahead will require some nuanced landscape decisions that can incorporate beaver habitats into large-scale nature recovery and restoration schemes. Beavers are showing that their impacts can offer added levels of ecosystem resilience to a changing climate that we would be wise to embrace.</p><img src="https://counter.theconversation.com/content/187739/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Joshua Larsen receives funding from the Natural Environment Research Council (NERC), UK. </span></em></p><p class="fine-print"><em><span>Annegret Larsen receives funding from the German Research Foundation (DFG), the Dutch Research Council (NWO), and the Federal Office for the Environment (FOEN, Switzerland). She is affiliated with Wageningen University & Research, The Netherlands. </span></em></p><p class="fine-print"><em><span>Matthew Dennis receives funding from the Natural Environment, (NERC), Arts and Humanities (AHRC) and Economic and Social (ESRC) Research Councils. </span></em></p>The role of beavers in safeguarding against our heating climate has become an interesting point of discussion. But just how important remains subject to debate.Joshua Larsen, Associate Professor in Water Science, University of BirminghamAnnegret Larsen, Assistant Professor in Geography, Wageningen UniversityMatthew Dennis, Senior Lecturer in Geographical Information Science, University of ManchesterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1831442022-07-04T13:15:33Z2022-07-04T13:15:33ZHedgehog conservation: how to make a garden nest box appealing – new research<figure><img src="https://images.theconversation.com/files/464815/original/file-20220523-26-ljqdjo.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4107%2C2735&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/hedgehog-scientific-name-erinaceus-europaeus-native-1530902369">Coatesy/Shutterstock</a></span></figcaption></figure><p>When large patches of woodland are swallowed by urban sprawl or when households replace long grass with artificial turf or refurbish buildings to repair cracks and crevices, wildlife populations are robbed of potential places to rest, breed and hibernate. That’s why conservation groups urge homeowners, where possible, to create wildlife-friendly habitats on their own land.</p>
<p>One artificial refuge that has long adorned gardens is the bird box. It is estimated that there are <a href="https://www.researchgate.net/publication/222692154_A_national_scale_inventory_of_resource_provision_within_domestic_gardens">4.7 million</a> of them in gardens across the UK. Some studies have reported that nest boxes (or bricks) can help birds to <a href="https://researchers.mq.edu.au/en/publications/provisioning-habitat-with-custom-designed-nest-boxes-increases-re">produce more chicks</a> and <a href="https://www.conservationevidence.com/actions/498">boost their populations</a> compared with birds nesting in areas without artificial refuges.</p>
<p>But whether and how animals actually use these refuges depends on their design, where they are placed and the conditions <a href="https://www.discoverwildlife.com/how-to/wildlife-gardening/garden-bird-nestbox-guide/">of the wider landscape</a>. In the wrong setting – or with the wrong design – wildlife can suffer harm or an increased risk of <a href="https://www.theguardian.com/environment/2016/feb/19/wacky-and-ornamental-nest-boxes-dangerous-for-young-birds-warns-rspb">being captured by predators</a>.</p>
<figure class="align-center ">
<img alt="A tit perched at the entrance of a wooden bird box mounted on a tree." src="https://images.theconversation.com/files/464812/original/file-20220523-25-kj9ccl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464812/original/file-20220523-25-kj9ccl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=463&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464812/original/file-20220523-25-kj9ccl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=463&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464812/original/file-20220523-25-kj9ccl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=463&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464812/original/file-20220523-25-kj9ccl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=582&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464812/original/file-20220523-25-kj9ccl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=582&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464812/original/file-20220523-25-kj9ccl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=582&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Artificial refuges such as bird boxes create nesting sites where natural options are limited.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/birdhouse-bird-198399557">Nadezhda Kulikova/Shutterstock</a></span>
</figcaption>
</figure>
<p>Relatively little is known about what makes a house a home for species other than birds, or how effective artificial refuges are for <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/brv.12776">conserving a species</a>. Even so, garden centres and other retailers offer a wide variety, ranging from ceramic houses for toads to wood and concrete roosts for bats. Many of these are made and installed with mammals in mind.</p>
<p>One such mammal is the nocturnal, ground-dwelling hedgehog. Hedgehogs have undergone a <a href="https://www.hedgehogstreet.org/state-of-britains-hedgehogs-2022/">long-term decline</a> and are listed as vulnerable on <a href="https://www.mammal.org.uk/science-research/red-list/">Britain’s red list of mammals</a>: some parts of the countryside may have seen numbers crash by up to 75% over the past 20 years. Where populations persist, hedgehogs often make use of residential gardens, and it is here where the public – by providing nest boxes (or “hedgehog houses”) – could play a significant role in their conservation. </p>
<p>In <a href="https://peerj.com/articles/13662/">a new study</a>, I found that you might be able to improve the chances of a hedgehog taking up residence in your garden nest box by, among other things, thinking carefully about where you position it and leaving out food and bedding material. </p>
<figure class="align-center ">
<img alt="A hedgehog surrounded by autumn leaves." src="https://images.theconversation.com/files/464814/original/file-20220523-29403-bajf7b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464814/original/file-20220523-29403-bajf7b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464814/original/file-20220523-29403-bajf7b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464814/original/file-20220523-29403-bajf7b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464814/original/file-20220523-29403-bajf7b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464814/original/file-20220523-29403-bajf7b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464814/original/file-20220523-29403-bajf7b.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">Hedgehog numbers have declined by between 30% and 75% across different parts of the UK countryside since 2000.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/hedgehog-dorset-uk-653760460">Colin Robert Varndell/Shutterstock</a></span>
</figcaption>
</figure>
<h2>The hedgehog housing census</h2>
<p>Charming images and videos of hedgehogs using nest boxes (both homemade and shop-bought) abound on <a href="https://www.hedgehogstreet.org/gallery/?category=hedgehog-house">social media</a>. Yet very little is known about how best to choose, make or install these refuges. That’s partly because people are advised to avoid disturbing nesting hedgehogs.</p>
<p>To resolve this, researchers at the University of Reading (including myself) and specialists at the conservation campaign group <a href="https://www.hedgehogstreet.org/">Hedgehog Street</a> launched the hedgehog housing census: an online questionnaire which gathered information on how nest boxes are used across the UK. </p>
<p>More than 5,000 surveys were returned. Using this data we examined how hedgehogs use boxes for different types of nesting. Hedgehogs typically build distinct nests for somewhere to rest during the day, somewhere to rear young and somewhere to hibernate over winter, and may move between more than one nest in each instance. For each type of nesting, we modelled how the use of a nest box appeared to have been influenced by its design and dimensions, plus features of the garden and environment.</p>
<p>For most seasons, the study showed that hedgehogs were more likely to have used a nest box where food – such as <a href="https://www.hedgehogstreet.org/help-hedgehogs/feed-hedgehogs/#:%7E:text=The%20hedgehog's%20natural%20diet%20mainly,hedgehog%20food%20in%20the%20garden%3F">meaty pet food</a> – and bedding were provided. Some gardeners left piles of dry leaves in a corner of the garden which hedgehogs could gather and drag into the box.</p>
<p>Hedgehogs were also more likely to use nest boxes where there was access between the front and back gardens, highlighting the importance of <a href="https://theconversation.com/hedgehog-highways-what-are-they-and-how-to-help-build-one-177785">connections between habitats</a>. This may be possible by cutting a hole in the bottom of a fence or leaving a gap beneath a gate to form a <a href="https://www.hedgehogstreet.org/help-hedgehogs/link-your-garden/">hedgehog highway</a>. Additionally, the likelihood of a hedgehog inhabiting a box tended to increase when they were placed under shelter such as shrubs, or on hard surfaces such as patios, and with the entrances oriented away from wide open spaces.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/463264/original/file-20220516-15-re3mf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A composite image showing eight different hedgehog house designs." src="https://images.theconversation.com/files/463264/original/file-20220516-15-re3mf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/463264/original/file-20220516-15-re3mf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=440&fit=crop&dpr=1 600w, https://images.theconversation.com/files/463264/original/file-20220516-15-re3mf5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=440&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/463264/original/file-20220516-15-re3mf5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=440&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/463264/original/file-20220516-15-re3mf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=553&fit=crop&dpr=1 754w, https://images.theconversation.com/files/463264/original/file-20220516-15-re3mf5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=553&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/463264/original/file-20220516-15-re3mf5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=553&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Artificial hedgehog refuges come in a variety of designs.</span>
<span class="attribution"><span class="source">Abi Gazzard</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The presence of dogs seemed only to have a negative effect during the vulnerable period of hibernation, which typically occurs between November and April. Surprisingly, badgers or foxes did not seem to deter hedgehogs from nesting in a box, though few people reported having seen either species in their garden. We also found that, during hibernation, nest boxes were more often used when the boxes were south-facing and within five metres of a building. This may be because these spots were warmer, and cosier nesting chambers help hibernating hedgehogs burn less energy. Too warm and hedgehogs could <a href="https://www.researchgate.net/publication/257697113_Impact_of_Climatic_Variation_on_the_Hibernation_Physiology_of_Muscardinus_avellanarius">wake up more frequently</a>, though. The optimum nest box temperature for hedgehogs – and the design features that might influence this – are not well understood.</p>
<p>The census also revealed where hedgehogs might prefer to make their own nests in gardens. Survey respondents reported evidence of 2,546 other nests used by hedgehogs in their gardens, including nests built under vegetation, such as long grass or shrubs, (46%), sheds (21%), woodpiles (15%), compost heaps (6%) and decking (6%).</p>
<p>Nest boxes – and gardens more broadly – provide important nesting habitats for the declining hedgehog. But there is still much we don’t know about how these artificial refuges compare to natural nests. This a field in which researchers must delve deeper, by untangling how nest box design affects occupancy and by trying to understand the consequences of using artificial refuges on hedgehog health, behaviour and abundance. For now, it’s clear that simple actions can improve the chances of a hedgehog using a nest box – a potentially critical part of nurturing the recovery of this species.</p><img src="https://counter.theconversation.com/content/183144/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Abi Gazzard received funding from the People's Trust for Endangered Species and British Hedgehog Preservation Society.</span></em></p>Garden surveys reveal what makes a house a home for Britain’s favourite mammal.Abi Gazzard, PhD in Ecology and Conservation, University of ReadingLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1760182022-02-15T18:47:11Z2022-02-15T18:47:11ZMicrochips, 3D printers, augmented reality: the high-tech tools helping scientists save our wildlife<figure><img src="https://images.theconversation.com/files/446416/original/file-20220215-17-1n4sgfi.jpg?ixlib=rb-1.1.0&rect=5%2C37%2C1911%2C928&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shania Watson</span></span></figcaption></figure><p>Around the world, Earth’s natural environments are being destroyed at a truly shocking scale. It means places animals need to shelter and breed, such as <a href="https://doi.org/10.1371/journal.pone.0041864">tree hollows</a>, <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/rra.1127">rock crevices</a> and <a href="https://doi.org/10.1002/ece3.3475">reefs</a>, are disappearing.</p>
<p>The only long-term way to protect these animals is to stop destroying their homes. But <a href="https://theconversation.com/the-governments-idea-of-national-environment-standards-would-entrench-australias-global-pariah-status-163082">political resistance</a>, <a href="https://www.theguardian.com/australia-news/2022/feb/02/more-money-than-ever-gas-companies-made-almost-1m-in-donations-to-labor-and-liberals">financial interests</a> and other factors often work to prevent this. So scientists must get creative to try and hold off extinction in the short term. </p>
<p>One way they do this is to create artificial habitat structures. Our <a href="https://esajournals.onlinelibrary.wiley.com/doi/10.1002/fee.2470">new research</a>, released today, examines how ingenious, high-tech innovation is making some structures more effective.</p>
<p>But artificial habitats are not a silver bullet. Some can harm animals, and they can be used by developers to distract from the damage their projects cause.</p>
<figure class="align-center ">
<img alt="albatross chick in artificial nest" src="https://images.theconversation.com/files/446411/original/file-20220215-13-8ruxk7.jpg?ixlib=rb-1.1.0&rect=64%2C9%2C6070%2C4893&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/446411/original/file-20220215-13-8ruxk7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/446411/original/file-20220215-13-8ruxk7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/446411/original/file-20220215-13-8ruxk7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/446411/original/file-20220215-13-8ruxk7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=603&fit=crop&dpr=1 754w, https://images.theconversation.com/files/446411/original/file-20220215-13-8ruxk7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=603&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/446411/original/file-20220215-13-8ruxk7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=603&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Technology is making some artificial habitat structures more effective.</span>
<span class="attribution"><span class="source">Matthew Newton, WWF Australia</span></span>
</figcaption>
</figure>
<h2>What are artificial habitat structures?</h2>
<p>Animals rely on specific environmental features to survive, grow, reproduce and sustain healthy populations. Artificial structures seek to replicate these habitats.</p>
<p>Some artificial homes provide habitat for just one species, while others benefit entire ecological communities. </p>
<p>They’ve been built for a huge variety of animals across the world, such as:</p>
<ul>
<li><p>boxes which mimic tree hollows, for <a href="https://link.springer.com/article/10.1007/s10531-009-9687-2">beetles</a> </p></li>
<li><p>nests made of coconut husks, for <a href="https://doi.org/10.2989/1814232X.2016.1186114">seabirds</a></p></li>
<li><p>nests made from mud brick and aerated concrete for the <a href="https://www.worldwildlife.org/pages/constructing-artificial-nests-for-shy-albatross">shy albatross</a></p></li>
<li><p>“hotels” based on fish traps, for <a href="https://theconversation.com/to-save-these-threatened-seahorses-we-built-them-5-star-underwater-hotels-130056">seahorses</a></p></li>
<li><p>ceramic poles that provide a surface for <a href="https://www.abc.net.au/news/2018-09-25/celebrations-at-spotted-handfish-artificial-habitat-success/10298020">spotted handfish</a> to lay eggs</p></li>
<li><p>textured <a href="https://www.livingseawalls.com.au/">tiles</a> attached to seawalls that provide habitat for up to 85 marine species.</p></li>
</ul>
<figure class="align-center ">
<img alt="moss-covered tiles attached to sea wall" src="https://images.theconversation.com/files/444726/original/file-20220207-27-7t5lyy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/444726/original/file-20220207-27-7t5lyy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/444726/original/file-20220207-27-7t5lyy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/444726/original/file-20220207-27-7t5lyy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/444726/original/file-20220207-27-7t5lyy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/444726/original/file-20220207-27-7t5lyy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/444726/original/file-20220207-27-7t5lyy.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">Artificial habitat, such as these tiles added to a seawall, can help a species’ short-term prospects.</span>
<span class="attribution"><span class="source">Alex Goad, Reef Design Lab</span></span>
</figcaption>
</figure>
<h2>How do new technologies help?</h2>
<p>More recently, wildlife conservationists have <a href="https://www.sciencedirect.com/science/article/pii/S2405872621000381">partnered</a> with engineers and designers to incorporate new and exciting technologies into artificial habitat design.</p>
<p>For example, researchers in Queensland recently installed <a href="https://doi.org/10.1002/wsb.1217">microchip-automated doors</a> on nest boxes for brushtail possums. </p>
<p>The doors opened only for microchipped possums as they came close, and most possums were trained to use them in about 11 days. Such technology may help to keep predators and other animals out of nest boxes provided for threatened species.</p>
<p>In New Zealand, small, native lizards hide from predatory house mice in the crevices of rock piles. Researchers used <a href="https://doi.org/10.1002/ecs2.3321">video game software</a> to visualise these 3D spaces and create “Goldilocks” rock piles - those with crevices big enough to let lizards in, but small enough to exclude mice. </p>
<p>3D printing to create artificial habitats is also becoming increasingly common. </p>
<p>Scientists have used a combination of computer simulation, augmented reality and 3D-printing to create <a href="https://doi.org/10.1111/2041-210X.13806">artificial owl nests</a> that resemble termite mounds in trees. </p>
<p>And researchers and designers have created 3D-printed <a href="https://www.livingseawalls.com.au/mission">rock pools</a> and <a href="https://www.reefdesignlab.com/">reefs</a> to provide habitat for sea life. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/urban-owls-are-losing-their-homes-so-were-3d-printing-them-new-ones-133626">Urban owls are losing their homes. So we're 3D printing them new ones</a>
</strong>
</em>
</p>
<hr>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/BMCfiLnncg8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A 3D-printed, modular artificial reef structure designed by Alex Goad.</span></figcaption>
</figure>
<h2>It’s not all good news</h2>
<p>Collaboration between scientists and engineers has enabled amazing new homes for wildlife, but there’s still lots of room <a href="https://onlinelibrary.wiley.com/doi/10.1111/brv.12776">for improvement</a>.</p>
<p>In some instances, artificial habitats may be detrimental to an animal’s health. For example, they may get <a href="https://www.sciencedirect.com/science/article/pii/S0006320710005392">too hot</a> or be placed in areas with little food or <a href="https://doi.org/10.1111/csp2.204">lots of predators</a>. </p>
<p>And artificial habitats can <a href="https://ttu-ir.tdl.org/handle/2346/73210">become ineffective</a> if not monitored and maintained.</p>
<p>Artificial habitat structures can also be used to <a href="https://doi.org/10.1111/1365-2664.13683">greenwash</a> environmentally destructive projects, or to <a href="https://www.smh.com.au/politics/federal/reef-on-path-to-destruction-and-clever-science-can-t-fix-it-20210407-p57h5i.html">distract</a> from taking serious action on climate change and habitat loss. </p>
<p>Further, artificial habitat structures are often only feasible at small scales, and can be expensive to build, deploy and maintain.</p>
<p>If the root causes of species decline - including habitat destruction and climate change - aren’t addressed, artificial habitat structures will <a href="https://theconversation.com/the-plan-to-protect-wildlife-displaced-by-the-hume-highway-has-failed-78087">do little</a> to help wildlife in the long-term.</p>
<figure class="align-center ">
<img alt="remains of a logged forest" src="https://images.theconversation.com/files/443966/original/file-20220202-17-1pjwnpq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/443966/original/file-20220202-17-1pjwnpq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/443966/original/file-20220202-17-1pjwnpq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/443966/original/file-20220202-17-1pjwnpq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/443966/original/file-20220202-17-1pjwnpq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/443966/original/file-20220202-17-1pjwnpq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/443966/original/file-20220202-17-1pjwnpq.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">The root causes of species decline, such as habitat destruction, must be addressed.</span>
<span class="attribution"><span class="source">Darcy Watchorn</span></span>
</figcaption>
</figure>
<h2>What next?</h2>
<p>It’s great that conservationists can create high-tech homes for wildlife – but it would be better if they didn’t have to.</p>
<p>Despite the dwindling numbers of countless species, environmental damage continues apace. </p>
<p>Native forests are <a href="https://theconversation.com/australia-has-failed-greater-gliders-since-they-were-listed-as-vulnerable-weve-destroyed-more-of-their-habitat-164872">cut down</a> and rivers are <a href="https://cdnsciencepub.com/doi/10.1139/cjfas-2015-0561">dammed</a>. Ocean shorelines are turned into <a href="https://www.nature.com/articles/s41893-020-00595-1">marinas or seawalls</a> and greenhouse gases are <a href="https://theconversation.com/australias-biggest-fossil-fuel-investment-for-a-decade-is-in-the-works-and-its-greenhouse-gas-emissions-will-be-horrifying-172955">pumped into the atmosphere</a>. </p>
<p>Such actions are the root cause of species decline.</p>
<p>We strongly encourage further collaboration between scientists and engineers to improve artificial habitat structures and help animal conservation. But as we help with one hand, we must stop destroying with the other.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/artificial-refuges-are-a-popular-stopgap-for-habitat-destruction-but-the-science-isnt-up-to-scratch-164401">Artificial refuges are a popular stopgap for habitat destruction, but the science isn't up to scratch</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/176018/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Darcy Watchorn receives funding from the Hermon Slade Foundation, Parks Victoria, the Conservation and Wildlife Research Trust, the Ecological Society of Australia, the Victorian Environmental Assessment Council, and the Geelong Naturalists Field Club. He is a member of the Ecological Society of Australia and the Society for Conservation Biology Oceania.</span></em></p><p class="fine-print"><em><span>Mitchell Cowan receives funding from the Department of Biodiversity, Conservation and Attractions, and Consolidated Minerals. He is a member of the Ecological Society of Australia, the Australian Wildlife Society, and the Australian Mammal Society.</span></em></p><p class="fine-print"><em><span>Tim Doherty receives funding from the Australian Research Council, Hermon Slade Foundation, NSW Environmental Trust, Australian Academy of Science and WWF Australia. He is policy committee chair for the Society for Conservation Biology Oceania and a member of the Ecological Society of Australia.</span></em></p>Artificial habitats are becoming more advanced, but they’re not a silver bullet.Darcy Watchorn, PhD Candidate, Deakin UniversityMitchell Cowan, PhD Candidate, Charles Sturt UniversityTim Doherty, ARC DECRA Fellow, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1745382022-01-12T16:43:33Z2022-01-12T16:43:33ZRegent honeyeaters were once kings of flowering gums. Now they’re on the edge of extinction. What happened?<p>Less than 80 years ago, regent honeyeaters ruled Australia’s flowering gum forests, with huge raucous flocks roaming from Adelaide to Rockhampton. </p>
<p>Now, there are less than 300 birds left in the wild. Habitat loss has pushed the survivors into little pockets across their once vast range. </p>
<p>Sadly, <a href="https://www.sciencedirect.com/science/article/abs/pii/S0006320721004821?via%3Dihub">our new research</a> shows these birds are now heading for rapid extinction. Unless we urgently boost conservation efforts, the regent honeyeater will follow the <a href="https://www.pnas.org/content/111/29/10636.short">passenger pigeon</a> into oblivion within the next 20 years. </p>
<p>If we let the last few die, the regent honeyeater will be only the second bird extinction on the Australian mainland since European colonisation, following the <a href="https://theconversation.com/100-years-ago-this-man-discovered-an-exquisite-parrot-thought-to-be-extinct-what-came-next-is-a-tragedy-we-must-not-repeat-171939">paradise parrot</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/440139/original/file-20220110-17-i5hkd0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/440139/original/file-20220110-17-i5hkd0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=840&fit=crop&dpr=1 600w, https://images.theconversation.com/files/440139/original/file-20220110-17-i5hkd0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=840&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/440139/original/file-20220110-17-i5hkd0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=840&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/440139/original/file-20220110-17-i5hkd0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1055&fit=crop&dpr=1 754w, https://images.theconversation.com/files/440139/original/file-20220110-17-i5hkd0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1055&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/440139/original/file-20220110-17-i5hkd0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1055&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Regent honeyeaters are one of the most endangered birds in Australia.</span>
<span class="attribution"><span class="source">Lachlan Hall.</span></span>
</figcaption>
</figure>
<h2>How did it come to this?</h2>
<p>With vivid yellow and black wings, embroidered body and warty faces, these honeyeaters are among Australia’s most spectacular birds.</p>
<p>John Gould, one of Australia’s earliest European naturalists, observed these birds in “immense flocks amongst the brushes of New South Wales”. He described the regent honeyeater as “the most pugnacious bird he ever saw”, noting they “reigned supreme in the largest, most heavily-flowering trees.” Their success in securing nectar supplies made them vital pollinators. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/only-the-lonely-an-endangered-bird-is-forgetting-its-song-as-the-species-dies-out-156950">Only the lonely: an endangered bird is forgetting its song as the species dies out</a>
</strong>
</em>
</p>
<hr>
<p>The world Gould saw is sadly a thing of the past. Regent honeyeater populations have plummeted, with the loss of over 90% of their <a href="https://academic.oup.com/jpe/article/5/1/109/1294916?login=true">preferred woodland habitats</a> to farmland. </p>
<p>You might wonder how this could be, given there are still large tracts of forest in Australia. But these are invariably on poorer soils and hilltops. Our remaining forests do not yield the rich nectar regent honeyeaters require for breeding. </p>
<p>As their habitat has declined, the surviving regent honeyeaters have been forced to compete with larger species – without the safety of their huge flocks. The result? The once common species <a href="https://www.tandfonline.com/doi/full/10.1080/01584197.2017.1333392">no longer reigns supreme</a>. </p>
<h2>Gone within 20 years</h2>
<p>Unless conservation actions are urgently stepped up, our research shows these birds will be extinct within 20 years. </p>
<p>We’ve known about the decline of regent honeyeaters since the <a href="https://search.informit.org/doi/abs/10.3316/informit.629962143894936">late 1970s</a>. In response, a recovery team including BirdLife Australia and Taronga Conservation Society launched a <a href="https://www.awe.gov.au/sites/default/files/documents/national-recovery-plan-regent-honeyeater.pdf">long-term recovery effort</a> to protect habitat, plant new trees and release zoo-bred birds. These efforts have slowed but not arrested the decline of these birds. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/439989/original/file-20220110-19-1y7oxfm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/439989/original/file-20220110-19-1y7oxfm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=730&fit=crop&dpr=1 600w, https://images.theconversation.com/files/439989/original/file-20220110-19-1y7oxfm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=730&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/439989/original/file-20220110-19-1y7oxfm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=730&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/439989/original/file-20220110-19-1y7oxfm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=917&fit=crop&dpr=1 754w, https://images.theconversation.com/files/439989/original/file-20220110-19-1y7oxfm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=917&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/439989/original/file-20220110-19-1y7oxfm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=917&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Regent honeyeaters are important pollinators of eucalypts.</span>
<span class="attribution"><span class="source">Liam Murphy.</span></span>
</figcaption>
</figure>
<p>In 2015, we began a <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/aec.13104">large-scale survey</a> to better understand their population decline. Regent honeyeaters are a notoriously <a href="https://www.difficultbirds.com/about-us">difficult bird</a> to study in the wild. As nomads, they wander long distances throughout their vast range in search of nectar in their <a href="https://woodiwild.org/tree-species/yellow-box-eucalyptus-melliodora/">favoured tree species</a>. Finding these birds is hard enough, let alone monitoring the population in detail.</p>
<p>After six years of intensive fieldwork, and with data from research in the 1990s and long term bird banding, we have finally gathered enough information to be able to understand the challenges for the few remaining wild birds. We now know their <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/ibi.12659">breeding success has declined</a> because their nests are raided and the chicks killed by aggressive native species, with <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ddi.12128">noisy miners a particular problem</a>. </p>
<p>We also know the wild birds are <a href="https://royalsocietypublishing.org/doi/10.1098/rspb.2021.0225">losing their song culture</a> because of a lack of older birds for fledglings to learn their songs.</p>
<p>Our fieldwork has given us accurate estimates of vital breeding data, such as how many young birds fledge for each adult female, how many birds are breeding and how well juveniles are surviving. We combined this with data from the decades of monitoring of zoo-bred and released birds to create <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/cobi.13414">population models</a>, which allow us to predict the future for the wild population under different conservation scenarios.</p>
<h2>Habitat is king</h2>
<p>What do the models show? That time is critical. To have any chance of getting the regent honeyeater back, we must build its numbers up enough for them to be able to roam in large flocks for protection. </p>
<p>How? First, we have to nearly double the nesting success rate for both wild and released zoo-bred birds. Too many young birds are dying early. That means we have to find nesting birds early in the breeding season and protect them from noisy miners, pied currawongs and even possums. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/439991/original/file-20220110-15-qmhcqw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/439991/original/file-20220110-15-qmhcqw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/439991/original/file-20220110-15-qmhcqw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/439991/original/file-20220110-15-qmhcqw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/439991/original/file-20220110-15-qmhcqw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/439991/original/file-20220110-15-qmhcqw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/439991/original/file-20220110-15-qmhcqw.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">Regent honeyeater nests need protection from predators.</span>
<span class="attribution"><span class="source">Nathan Sherwood</span></span>
</figcaption>
</figure>
<p>Next, we have to boost the numbers of zoo-bred birds released in the Blue Mountains, and maintain these numbers for at least twenty years. Staff at Taronga Conservation Society are preparing zoo-bred birds for the trials of the wild by exposing them to competition in flight aviaries, song tutoring young males and improving <a href="https://www.frontiersin.org/articles/10.3389/fcosc.2021.669563/full?&utm_source=Email_to_authors_&utm_medium=Email&utm_content=T1_11.5e1_author&utm_campaign=Email_publication&field=&journalName=Frontiers_in_Conservation_Science&id=669563">husbandry practices in zoos</a> to increase survival in the wild.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/should-we-cull-noisy-miners-after-decades-of-research-these-aggressive-honeyeaters-are-still-outsmarting-us-169524">Should we cull noisy miners? After decades of research, these aggressive honeyeaters are still outsmarting us</a>
</strong>
</em>
</p>
<hr>
<p>Finally, our models clearly show regent honeyeaters will only become self-sustaining if we do much more to secure their habitat. Their remaining pockets of habitat are simply too small. We must protect all remaining habitat, restore degraded habitat and <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/aec.12878">control noisy miners</a>. </p>
<p>Without habitat, other conservation efforts will be pointless. The honeyeater will simply never reach flock sizes large enough to muscle their way back into the surprisingly competitive business of drinking nectar. </p>
<p>Unfortunately, we continue to destroy essential regent honeyeater habitat in some areas even as we attempt to restore lost habitat elsewhere. For example, if the Warragamba Dam in the Blue Mountains is <a href="https://www.smh.com.au/environment/conservation/cracks-in-warragamba-dam-plan-revealed-by-leaked-documents-20200721-p55e3e.html">raised</a> it will flood essential habitat and make it even harder to bring back our iconic honeyeater. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/440140/original/file-20220110-19-19g9ykm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/440140/original/file-20220110-19-19g9ykm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/440140/original/file-20220110-19-19g9ykm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/440140/original/file-20220110-19-19g9ykm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/440140/original/file-20220110-19-19g9ykm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/440140/original/file-20220110-19-19g9ykm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/440140/original/file-20220110-19-19g9ykm.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">Ongoing destruction of the habitat of regent honeyeaters is likely to lock-in their extinction.</span>
<span class="attribution"><span class="source">Lachlan Hall</span></span>
</figcaption>
</figure>
<h2>The status quo is not enough</h2>
<p>For decades, conservationists and researchers have worked to save the regent honeyeater. Despite this tireless work, the species is inching towards the exit. If we maintain the status quo, we will lose it. </p>
<p>We must think bigger. Nest protection and release of zoo-bred birds can help get flock sizes up, but these efforts will be pointless if there are no blossoms for them to drink from. </p>
<p>Like the regent honeyeater, the passenger pigeon sought safety in numbers. We now know its extinction <a href="https://www.sciencedirect.com/science/article/abs/pii/S0006320714003401">could have been predicted</a>, if modern risk assessments had been available. Those same assessments and models tell us very clearly what will happen to the regent honeyeater. </p>
<p>It is too late for the passenger pigeon. It is not too late to save the regent honeyeater. But only if we act now. </p>
<p><em>Monique Van Sluys (Taronga Conservation Society) and Dean Ingwersen (Birdlife Australia) contributed to this article</em></p><img src="https://counter.theconversation.com/content/174538/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rob Heinsohn receives funding from the Australian Research Council. The study reported here was funded by an Australian Government Wildlife and Habitat Bushfire Recovery Program grant to Birdlife Australia.</span></em></p><p class="fine-print"><em><span>Dejan Stojanovic receives funding from an Australian Government Natural Heritage Trust grant. </span></em></p><p class="fine-print"><em><span>Ross Crates receives funding from the NSW Office of Environment and Heritage, BirdLife Australia, CWP renewables and the Department of Agriculture, Water and Environment.</span></em></p>These iconic honeyeaters once ruled the flowering gum trees in massive numbers. But habitat loss means they’re on the edge of extinction.Rob Heinsohn, Professor of Evolutionary and Conservation Biology, Australian National UniversityDejan Stojanovic, Postdoctoral Fellow, Australian National UniversityRoss Crates, Postdoctoral fellow, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1678012021-09-16T20:07:49Z2021-09-16T20:07:49ZDestroying vegetation along fences and roads could worsen our extinction crisis — yet the NSW government just allowed it<figure><img src="https://images.theconversation.com/files/421483/original/file-20210916-13-1ppd6uk.jpg?ixlib=rb-1.1.0&rect=0%2C62%2C6000%2C3925&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>What do koalas, barking owls, greater gliders, southern rainbow skinks, native bees, and regent honeyeaters all have in common? Like many native species, they can all be found in vegetation along fences and roadsides outside formal conservation areas.</p>
<p>They may be relatively small, but these patches and strips conserve critical remnant habitat and have <a href="https://www.pnas.org/content/116/3/909">disproportionate conservation value worldwide</a>. They represent the last vestiges of once-expansive tracts of woodland and forests, long lost to the chainsaw or plough. </p>
<p>And yet, the NSW government last week <a href="https://legislation.nsw.gov.au/view/pdf/asmade/act-2020-37">made it legal</a> for <a href="https://www.rfs.nsw.gov.au/__data/assets/pdf_file/0014/231422/Rural-Boundary-Clearing-Code-for-New-South-Wales.pdf">rural landholders to clear</a> vegetation on their properties, up to 25 metres from their property boundaries, without approval. This radical measure is proposed to protect people and properties from fires, despite the lack of such an explicit recommendation from federal and state-based inquiries into the devastating 2019-20 bushfires. </p>
<p>This is poor environmental policy that lacks apparent consideration or justification of its potentially substantial <a href="https://www.annualreviews.org/doi/abs/10.1146/annurev.ecolsys.34.011802.132419">ecological costs</a>. It also gravely undermines the NSW government’s recent announcement of a plan for <a href="https://www.theguardian.com/australia-news/2021/sep/07/zero-extinction-target-for-nsw-national-parks-welcomed-by-environment-groups">“zero extinction”</a> within the state’s national parks, as the success of protected reserves for conservation is greatly enhanced by connection with surrounding “off-reserve” habitat. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1437209505968705540"}"></div></p>
<h2>Small breaks in habitat can have big impacts</h2>
<p>A 25m firebreak might sound innocuous, but when multiplied by the length of property boundaries in NSW, the scale of potential clearing and impacts is alarming, and could run into the hundreds of thousands of kilometres.</p>
<p>Some plants, animals and fungi live in these strips of vegetation permanently. Others use them to travel between larger habitat patches. And for migratory species, the vegetation provides crucial refuelling stops on long distance journeys. </p>
<p>For example, the <a href="https://t.co/pJ66g1aQ2Z?amp=1">roadside area in Victoria’s Strathbogie Ranges</a> shown below is home to nine species of tree-dwelling native mammals: two species of brushtail possums, three species of gliders (including threatened greater gliders), common ringtail possums, koalas, brush-tailed phascogales, and agile antenchinus (small marsupials).</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/421223/original/file-20210914-15-vi3z7x.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421223/original/file-20210914-15-vi3z7x.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=604&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421223/original/file-20210914-15-vi3z7x.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=604&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421223/original/file-20210914-15-vi3z7x.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=604&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421223/original/file-20210914-15-vi3z7x.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=759&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421223/original/file-20210914-15-vi3z7x.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=759&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421223/original/file-20210914-15-vi3z7x.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=759&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Roadside and fenceline vegetation is often the only substantial remnant vegetation remaining in agricultural landscapes. This section, in northeast Victoria’s Strathbogie Ranges, running north to south from the intersection, is home to high arboreal mammal diversity, including the threatened greater glider.</span>
<span class="attribution"><span class="source">Google Earth</span></span>
</figcaption>
</figure>
<p>Many of these <a href="https://www.publish.csiro.au/book/3010/">species depend on tree hollows</a> that can take a hundred years to form. If destroyed, they are effectively irreplaceable.</p>
<p>Creating breaks in largely continuous vegetation, or further fragmenting already disjointed vegetation, will not only directly destroy habitat, but can <a href="https://www.annualreviews.org/doi/abs/10.1146/annurev.ecolsys.34.011802.132419">severely lower the quality of adjoining habitat</a>. </p>
<p>This is because firebreaks of 25m (or 50m where neighbouring landholders both clear) could prevent the movement and dispersal of many plant and animal species, including critical pollinators such as native bees.</p>
<p>An entire suite of woodland birds, including the critically endangered regent honeyeater, are threatened because they depend on thin strips of vegetation communities that often occur inside fence-lines on private land. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/421335/original/file-20210915-24-16vmwbo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421335/original/file-20210915-24-16vmwbo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=284&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421335/original/file-20210915-24-16vmwbo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=284&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421335/original/file-20210915-24-16vmwbo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=284&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421335/original/file-20210915-24-16vmwbo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=357&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421335/original/file-20210915-24-16vmwbo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=357&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421335/original/file-20210915-24-16vmwbo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=357&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Ecologically-sensitive fence replacement in regent honeyeater breeding habitat.</span>
<span class="attribution"><span class="source">Ross Crates</span></span>
</figcaption>
</figure>
<p>For instance, <a href="https://www.difficultbirds.com/study-species#regent-honeyeater">scientific monitoring</a> has shown five pairs of regent honeyeaters (50% of all birds located so far this season) are nesting or foraging within 25m of a single fence-line in the upper Hunter Valley. This highlights just how big an impact the loss of one small, private location could have on a species already on the brink of extinction. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/only-the-lonely-an-endangered-bird-is-forgetting-its-song-as-the-species-dies-out-156950">Only the lonely: an endangered bird is forgetting its song as the species dies out</a>
</strong>
</em>
</p>
<hr>
<p>But it’s not just regent honeyeaters. The management plan for the vulnerable <a href="https://www.environment.nsw.gov.au/threatenedspeciesapp/profile.aspx?id=10140">glossy black cockatoo</a> makes specific recommendation that vegetation corridors be maintained, as they’re essential for the cockatoos to travel between suitable large patches. </p>
<p>Native bee conservation also relies on the protection of <a href="https://www.sciencedirect.com/science/article/pii/S0006320712001097?casa_token=nzq8uIrMuIUAAAAA:0D0qlHMERwunqIS9YKJ1IZM065OHICEuq4-eWWDv2A8_ZpS_p7_HRd9OAgYA0p9r-Qnb0C3Sxg">remnant habitat adjoining fields</a>. Continued removal of habitat on private land will hinder chances of conserving these species. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/421495/original/file-20210916-13-cu52nq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/421495/original/file-20210916-13-cu52nq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421495/original/file-20210916-13-cu52nq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421495/original/file-20210916-13-cu52nq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421495/original/file-20210916-13-cu52nq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421495/original/file-20210916-13-cu52nq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421495/original/file-20210916-13-cu52nq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421495/original/file-20210916-13-cu52nq.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">Glossy black cockatoos rely on remnant patches of vegetation.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Disastrous clearing laws</h2>
<p>The new clearing code does have some regulations in place, albeit meagre. For example, on the Rural Fire Service website, <a href="https://www.rfs.nsw.gov.au/news-and-media/general-news/boundary-clearing-measures">it says</a> the code allows “clearing only in identified areas, such as areas which are zoned as Rural, and which are considered bush fire prone”. And according to the RFS <a href="https://www.rfs.nsw.gov.au/plan-and-prepare/boundary-clearing-tool">boundary clearing tool</a> landowners aren’t allowed to clear vegetation near watercourses (riparian vegetation).</p>
<p>Even before introducing this new code, NSW’s clearing laws were an environmental disaster. In 2019, The <a href="https://www.audit.nsw.gov.au/our-work/reports/managing-native-vegetation">NSW Audit Office found</a>: </p>
<blockquote>
<p>clearing of native vegetation on rural land is not effectively regulated [and] action is rarely taken against landholders who unlawfully clear native vegetation. </p>
</blockquote>
<p>The data back this up. In 2019, over <a href="https://www.environment.nsw.gov.au/topics/animals-and-plants/native-vegetation/landcover-monitoring-and-reporting/2019-landcover-change-reporting">54,500 hectares</a> were cleared in NSW. Of this, 74% was “<a href="https://www.theguardian.com/australia-news/2021/jun/29/alarming-rise-in-land-clearing-prompts-calls-for-urgent-overhaul-of-nsw-laws">unexplained</a>”, which <a href="https://www.environment.nsw.gov.au/topics/animals-and-plants/native-vegetation/landcover-monitoring-and-reporting/2019-landcover-change-reporting/unexplained-clearing">means</a> the clearing was either lawful (but didn’t require state government approval), unlawful or not fully compliant with approvals. </p>
<p>Landholders need to show they’ve complied with clearing laws only after they’ve already cleared the land. But this is too late for wildlife, including plant species, <a href="https://theconversation.com/the-50-beautiful-australian-plants-at-greatest-risk-of-extinction-and-how-to-save-them-160362">many of which are threatened</a>.</p>
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<strong>
Read more:
<a href="https://theconversation.com/the-50-beautiful-australian-plants-at-greatest-risk-of-extinction-and-how-to-save-them-160362">The 50 beautiful Australian plants at greatest risk of extinction — and how to save them</a>
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<p>Landholders follow <a href="https://theconversation.com/land-clearing-on-the-rise-as-legal-thinning-proves-far-from-clear-cut-79419">self-assessable codes</a>, but problems with these policies <a href="https://lgnsw.org.au/common/Uploaded%20files/Submissions/submission-to-rfs-on-10-50-vegetation-clearing-code-of-practice-review-nov-14.pdf">have been identified</a> time and time again — they cumulatively allow a huge amount of clearing, and compliance and enforcement are ineffective. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/mDccRnYMU8w?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Vegetation along roadsides and close to fences can be critical habitat for greater gliders.</span></figcaption>
</figure>
<p>We also know, thanks to <a href="https://theconversation.com/the-plan-to-protect-wildlife-displaced-by-the-hume-highway-has-failed-78087">various case studies</a>, the policy of “offsetting” environmental damage by improving biodiversity elsewhere doesn’t work.</p>
<p>So, could the federal <a href="https://www.environment.gov.au/epbc/about">environment and biodiversity protection law</a> step in if habitat clearing gets out of hand? Probably not. The problem is these 25m strips are <a href="https://conbio.onlinelibrary.wiley.com/doi/abs/10.1111/csp2.117">unlikely to be referred</a> in the first place, or be considered a <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/conl.12694">“significant impact”</a> to trigger the federal law. </p>
<h2>The code should be amended</h2>
<p>Nobody disputes the need to keep people and their assets safe against the risks of fire. The code should be amended to ensure clearing is only permitted where a genuinely clear and measurable fire risk reduction is demonstrated. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/421506/original/file-20210916-27-srsgtz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421506/original/file-20210916-27-srsgtz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=486&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421506/original/file-20210916-27-srsgtz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=486&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421506/original/file-20210916-27-srsgtz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=486&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421506/original/file-20210916-27-srsgtz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=611&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421506/original/file-20210916-27-srsgtz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=611&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421506/original/file-20210916-27-srsgtz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=611&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Many native bees, like this blue-banded bee (<em>Amegilla</em> sp.), will use the nesting and foraging resources available in remnant vegetation patches.</span>
<span class="attribution"><span class="source">Michael Duncan</span></span>
</figcaption>
</figure>
<p>Granting permission to clear considerable amounts of native vegetation, hundreds if not thousands of metres away from homes and key infrastructure in large properties is hard to reconcile, and it seems that no attempt has been made to properly justify this legislation.</p>
<p>We should expect that a comprehensive assessment of the likely impacts of a significant change like this would inform public debate prior to decisions being made. But to our knowledge, no one has analysed, or at least revealed, how much land this rule change will affect, nor exactly what vegetation types and wildlife will likely be most affected. </p>
<p>A potentially devastating environmental precedent is being set, if other regions of Australia were to follow suit. The <a href="https://theconversation.com/existential-threat-to-our-survival-see-the-19-australian-ecosystems-already-collapsing-154077">environment</a> and Australians deserve better.</p>
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Read more:
<a href="https://theconversation.com/existential-threat-to-our-survival-see-the-19-australian-ecosystems-already-collapsing-154077">'Existential threat to our survival': see the 19 Australian ecosystems already collapsing</a>
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<p><em>Clarification: some text has been added to clarify the land cleared is on the landowner’s property, not outside their property boundary</em></p><img src="https://counter.theconversation.com/content/167801/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Euan Ritchie receives funding from the Australian Research Council, Australian Government Bushfire Recovery program, Australian Geographic, Parks Victoria, Department of Environment, Land, Water and Planning, WWF, and the Bushfire and Natural Hazards CRC. Euan Ritchie is a Director (Media Working Group) of the Ecological Society of Australia, and a member of the Australian Mammal Society.</span></em></p><p class="fine-print"><em><span>Ben Moore receives funding from The Department of Planning, Industry and Environment (NSW) and the Natural Resources Commission (NSW). He is a member of the Ecological Society of Australia and The Australian Mammal Society.</span></em></p><p class="fine-print"><em><span>Mark Hall is a member of the Ecological Society of Australia and the Australian Native Bee Association</span></em></p><p class="fine-print"><em><span>Megan C Evans receives funding from the Australian Research Council through a Discovery Early Career Research Award fellowship and has previously been funded by the National Environmental Science Program's Threatened Species Recovery Hub. </span></em></p><p class="fine-print"><em><span>Jen Martin and Ross Crates 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>Under a new code, rural landholders in NSW will be allowed to clear up to 25 metres of land outside their property boundary. This will be devastating for the wildlife that live or migrate there.Euan Ritchie, Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin UniversityBen Moore, Senior Lecturer in Ecology, Hawkesbury Institute for the Environment, Western Sydney UniversityJen Martin, Leader, Science Communication Teaching Program, The University of MelbourneMark Hall, Postdoctoral research fellow, Hawkesbury Institute for the Environment, Western Sydney UniversityMegan C Evans, Lecturer and ARC DECRA Fellow, UNSW SydneyRoss Crates, Postdoctoral fellow, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1669182021-09-16T07:09:14Z2021-09-16T07:09:14ZAfrican leopard sighting raises hopes for their conservation in southern Cameroon<figure><img src="https://images.theconversation.com/files/420450/original/file-20210910-16-exrb9f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Africa's leopards, like this one in Botswana, are increasingly under threat.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>In recent years, ecologists have been able to confirm the existence of species previously thought to be lost from former parts of their range. </p>
<p>For example, in 2020, lowland gorillas <a href="https://news.mongabay.com/2020/02/camera-traps-confirm-presence-of-lowland-gorillas-in-central-mainland-equatorial-guinea-for-first-time-in-over-a-decade/">were confirmed</a> to persist in central mainland Equatorial Guinea by University of the West of England researchers. This year, Babirusa, a southeast Asian wild pig species, <a href="https://news.mongabay.com/2021/07/camera-trap-cameo-for-buru-island-babirusa-last-seen-26-years-ago/">were documented</a> for the first time in 26 years on Buru Island, Indonesia. </p>
<p>Collecting this evidence is possible due to the increasing use of remotely triggered cameras, commonly known as camera traps. Camera traps are triggered by motion and take photos of an animal that passes in front of the camera’s detection zone. </p>
<p>By deploying cameras in wildlife habitat, we can gather valuable information about the animals that live there and how many may be left. This is especially important in areas subject to intense human pressure, which has increasingly left species under threat. </p>
<p>In 2019, our research team deployed 19 camera traps in southern Cameroon in Central Africa. <a href="https://www.researchgate.net/publication/349039119_First_direct_leopard_evidence_in_20_years_in_Campo-Ma'an_conservation_area_Cameroon">A sighting of an adult leopard</a> was captured by one of our camera traps in the Campo-Ma’an area. This was the first sighting of a leopard in 20 years. </p>
<p>Photos showed only one individual, but its presence provided real evidence that leopards still occur in this conservation area. This would make leopards the apex predator in this area.</p>
<p>The leopard has the widest range of any big cat species in Africa, and can persist in a range of habitat types including savanna and rainforest environments. Population estimates are not known, though numbers in Africa are thought to be declining. A <a href="https://peerj.com/articles/1974/#p-8">2016 study</a> estimated that the African leopard’s range has reduced to 67%.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/exploitation-changes-leopard-behaviour-with-long-term-genetic-costs-136650">Exploitation changes leopard behaviour with long-term genetic costs</a>
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<p>There is little information about leopard populations in Central Africa but in sub-Saharan Africa as a whole, prey loss within protected areas as well as habitat loss and illegal hunting are expected to have played an important role <a href="https://www.iucnredlist.org/species/15954/163991139#assessment-information">in leopard declines in this region</a>. </p>
<p>Although the Congo Basin was previously thought to be a stronghold for leopards, they are now believed to be absent in many parts of this region, so our recent sighting of a leopard in Campo-Ma'an shows the importance of conservation efforts to protect leopard habitat and their prey. </p>
<p>In light of increasing habitat loss and fragmentation in the region, further research in our study area is urgently needed. </p>
<h2>Campo-Ma’an</h2>
<p>The region is part of the Congo Basin which, besides Cameroon, spans parts of Equatorial Guinea, the Central African Republic, the Democratic Republic of Congo, the Republic of Congo and Gabon. </p>
<p>The Congo Basin is a biodiversity hotspot that is home to thousands of species and is the second largest tropical rainforest on the planet after the Amazon. This forest system is also home to several endangered species, including the western lowland gorilla, forest elephant, chimpanzee, mandrill and giant pangolin.</p>
<p><a href="https://fedec.cm/en/le-parc-national-de-campo-maan/">Campo-Ma’an National Park </a>is a 2,680 square km protected area in southern Cameroon. Campo-Ma’an was thought to have one of the last remaining leopard populations in the region. But after decades of hunting and forest loss, there had been no indisputable evidence that leopards were still there. </p>
<h2>An unexpected find</h2>
<p>In 2019, one of our camera traps photographed a leopard, as an unexpected byproduct of a study on the ecology of endangered forest elephants in Campo-Ma’an. </p>
<p>Cameras were deployed in areas thought to be used by elephants so we were surprised to see an adult leopard in one of the photos. </p>
<p>Knowing that leopards still exist in Campo-Ma’an helped us secure research funds to expand our camera trapping efforts in the area in 2022. Working with local communities and the Ministry of Forestry and Wildlife in Cameroon will help us collect data to better understand what leopards need to be able to live in this area and importantly, prevent human-leopard conflict. </p>
<p>Our team will carry out an extensive camera trap survey throughout the Campo-Ma’an conservation area to gather more information about leopard habitat use there. This will help us get a better idea of how many leopards there are, and in turn, encourage strategies to protect the species.</p>
<p>This is urgently needed as human disturbance and encroachment is a major threat to wildlife in the area. Campo-Ma’an National Park is surrounded by more than 100 human settlements, as well as palm oil plantations and logging concessions. </p>
<p>Our findings were valuable in confirming the presence of leopards in the area but a great deal more work needs to be done. Our work will form the basis of a long-term wildlife monitoring programme in the region which we hope will contribute to conservation efforts in Campo-Ma’an, for leopards as well as the many other endangered species that live there.</p><img src="https://counter.theconversation.com/content/166918/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>Recent sighting of a leopard in the Campo-Ma’an National Park area of Southern Cameroon shows the importance of conservation efforts.Robert Weladji, Professor, Biology Graduate Program Director, Biology, Concordia UniversityAlys Granados, Post doctoral researcher, University of British ColumbiaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1535462021-02-02T16:22:06Z2021-02-02T16:22:06ZParadox lost: wetlands can form in deserts, but we need to find and protect them<figure><img src="https://images.theconversation.com/files/381954/original/file-20210202-23-83heet.jpg?ixlib=rb-1.1.0&rect=0%2C65%2C4000%2C2179&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An oasis in the Sahara Desert, Libya.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/umm-alma-lake-idyllic-oasis-awbari-72697231">Patrick Poendl/Shutterstock</a></span></figcaption></figure><p>Once dismissed as dank and bug-infested backwaters – good only for draining and destroying to make farmland – the world’s wetlands may finally be having their moment in the sun. In the UK, the government is expected to nominate a vast expanse of blanket bogs in the far north of Scotland as <a href="https://www.theguardian.com/environment/2020/nov/13/world-heritage-status-for-scottish-peat-bogs-could-help-uk-hit-net-zero-goals">a world heritage site</a>. They might not sound attractive to some people, but these bogs are among the world’s biggest stores of carbon, they provide abundant freshwater and they harbour a miraculous array of wildlife.</p>
<p>This recognition that wetlands are worth protecting has its roots in an agreement signed 50 years ago, on February 2 1971 in Ramsar, Iran. The Ramsar Convention is the only international convention that’s dedicated to protecting a specific ecosystem, though in reality, the “wetlands” that the convention refers to can mean anything from swamps and peat bogs to shallow lakes and estuaries. </p>
<p>So far, 171 countries have signed up to the convention and more than 2,400 sites are protected under it, representing between 10% and 20% of the world’s remaining wetlands and collectively covering an area larger than Mexico. Under the convention, governments are committed to the “wise use” and upkeep of wetlands in their borders, but this doesn’t necessarily keep them safe. Nearly 90% of the world’s wetlands have been <a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3261606">lost since 1700</a>, and those which remain are being lost at a rate that’s <a href="https://www.global-wetland-outlook.ramsar.org/">three times faster than forests</a>. </p>
<figure class="align-center ">
<img alt="A boat sails past dry grassland with elephants." src="https://images.theconversation.com/files/381953/original/file-20210202-17-1eoxus8.JPG?ixlib=rb-1.1.0&rect=0%2C54%2C2816%2C1821&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/381953/original/file-20210202-17-1eoxus8.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/381953/original/file-20210202-17-1eoxus8.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/381953/original/file-20210202-17-1eoxus8.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/381953/original/file-20210202-17-1eoxus8.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/381953/original/file-20210202-17-1eoxus8.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/381953/original/file-20210202-17-1eoxus8.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">The floodplain wetlands of the Chobe River, on the Botswana-Namibia border.</span>
<span class="attribution"><span class="source">Stephen Tooth</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>From agricultural expansion and river diversion to invasive species and climate change, wetlands face numerous threats. But one of the gravest may be ignorance. We still don’t know enough about these habitats, and they can still surprise even seasoned scientists like us. Perhaps most surprising of all are those wetlands that seem to confound all logic by thriving amid some of the driest places on Earth.</p>
<h2>Boom and bust amid the dust</h2>
<p>Drylands are regions of the world where more water evaporates than falls from the sky. Warm drylands cover about <a href="https://www.unep-wcmc.org/resources-and-data/global-drylands--a-un-system-wide-response">40% of the Earth’s surface</a>, but about 28% of this area overlaps with <a href="https://www.millenniumassessment.org/documents/document.291.aspx.pdf">inland rivers and wetlands</a>. The result is marshes, swamps, floodplains, and oases in a landscape where water is otherwise scarce. </p>
<p>Wetlands are especially important in dry landscapes, as they can be the only supply of freshwater and food for people and wildlife for miles around. Some wetlands in drylands are famous. Iraq’s Mesopotamian Marshes (largely believed to be the inspiration for the Garden of Eden) and the Nile River floodplain are both largely surrounded by desert, but it’s here in these Middle Eastern wetlands where modern human civilisation emerged.</p>
<p>For every famous example, there are thousands that remain unidentified and unmapped. That’s partly because these unique habitats change frequently, sometimes vanishing completely before eventually reappearing. Seasonal downpours can sustain these green patches for a while if the soil doesn’t drain well and is particularly good at holding onto the water. Other wetlands in drylands are more permanent thanks to a source of water below ground, with enough seeping to the surface to maintain damp conditions. But some wetlands can lie dormant until they’re reawakened by river flooding and suddenly erupt in vibrant shades of green.</p>
<figure class="align-center ">
<img alt="An aerial view of a dry plain on one side and an expanse of green and damp habitat on the other." src="https://images.theconversation.com/files/381950/original/file-20210202-19-6sw5nu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/381950/original/file-20210202-19-6sw5nu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/381950/original/file-20210202-19-6sw5nu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/381950/original/file-20210202-19-6sw5nu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/381950/original/file-20210202-19-6sw5nu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/381950/original/file-20210202-19-6sw5nu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/381950/original/file-20210202-19-6sw5nu.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">The riverine woodland and reed swamps of the Macquarie Marshes in Australia.</span>
<span class="attribution"><span class="source">Stephen Tooth</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Many wetlands in drylands are small and temporary, only hosting a thriving ecosystem for a few months following good rains that may occur years or even decades apart. Depending on the scale and their timing, scientific surveys may miss these hidden treasures. The boom-and-bust wetlands that are adapted to emerge following occasional pulses of water are so understudied that we’re in danger of losing them before we even realise their presence and understand their full value.</p>
<p>All wetlands are prone to change over time. Sometimes rivers change their course and switch where floodwaters, sediment and nutrients end up. Older wetlands dry up, while newer ones develop. These changes create a mosaic of different landforms with different grades of wetness and soil types, helping to create a wide range of habitats that support an equally vast range of wildlife. Understanding the processes that give rise to these wetlands can help us maintain them, but the first step must be debunking the idea that such habitats are static, unchanging features of the landscape. </p>
<figure class="align-center ">
<img alt="A damp, green patch with small pools surrounded by dry mountain plains." src="https://images.theconversation.com/files/381959/original/file-20210202-23-1olt4da.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/381959/original/file-20210202-23-1olt4da.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/381959/original/file-20210202-23-1olt4da.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/381959/original/file-20210202-23-1olt4da.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/381959/original/file-20210202-23-1olt4da.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/381959/original/file-20210202-23-1olt4da.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/381959/original/file-20210202-23-1olt4da.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">The Tso Kar lake brings a splash of green to the dry Karakorum mountain plains of India.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/view-tso-kar-lake-karakorum-mountains-682951765">Rafal Cichawa/Shutterstock</a></span>
</figcaption>
</figure>
<p>Despite some limitations, the Ramsar Convention remains one of the best mechanisms for protecting and highlighting the value of wetlands, even if many still go under the radar. Though there are signs of change. India <a href="https://www.ramsar.org/news/india-adds-a-high-altitude-wetland-complex-to-the-ramsar-list">recently added</a> a complex of shallow lakes high up in a dry mountain to the Ramsar list. Numerous threatened species may benefit from this habitat, including the vulnerable snow leopard. Hopefully other countries will follow suit and recognise more of these rare and beautiful places before it’s too late.</p><img src="https://counter.theconversation.com/content/153546/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Stephen Tooth received funding from the Universities UK International (UUKi) Rutherford Fund Strategic Partner Grants Programme, the British Council Higher Education Links Grants scheme, and the Aberystwyth University Global Challenges Research Fund.</span></em></p><p class="fine-print"><em><span>Peyton Lisenby received funding from the Universities UK International (UUKi) Rutherford Fund Strategic Partner Grants Programme as a Rutherford Fellow.</span></em></p><p class="fine-print"><em><span>Timothy J. Ralph does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Wetlands in drylands seem impossible, but their benefits to people and wildlife are very real.Stephen Tooth, Professor of Physical Geography, Aberystwyth UniversityPeyton Lisenby, Assistant Professor of Geosciences, Midwestern State UniversityTimothy J. Ralph, Senior Lecturer in Environmental Sciences, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1486342020-11-04T19:23:26Z2020-11-04T19:23:26ZUrban golf courses are biodiversity oases. Opening them up puts that at risk<figure><img src="https://images.theconversation.com/files/367333/original/file-20201103-21-1q2etgj.jpg?ixlib=rb-1.1.0&rect=0%2C10%2C1757%2C1061&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Nicholas Williams</span>, <span class="license">Author provided</span></span></figcaption></figure><p>High demand for green space under COVID restrictions led councils in Melbourne to temporarily open golf courses to non-golfers and <a href="https://www.theage.com.au/politics/victoria/locals-want-covid-normal-to-include-turning-golf-course-into-parkland-20200925-p55zea.htm">fuelled public calls to “unlock”</a> or repurpose them permanently. However, this must be done carefully because many golf courses are oases of biodiversity in Australian cities. If more people visit golf courses, increased disturbance of wildlife is just one of the results that may be incompatible with their nature conservation values. </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/our-cities-are-full-of-parks-so-why-are-we-looking-to-golf-courses-for-more-open-space-147559">Our cities are full of parks, so why are we looking to golf courses for more open space?</a>
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<p>Between 2011 and 2014 <a href="https://girg.science.unimelb.edu.au/ecosystem-services-from-large-urban-green-spaces/">we studied</a> the biodiversity of green spaces throughout Melbourne’s south-eastern suburbs. We compared golf courses to nearby public parks and residential areas as these are the land uses that most commonly replace golf courses when they close. </p>
<p>The results surprised us. Golf courses contained the greatest diversity and abundance of beetles, bees, birds and bats of all the green spaces we studied. We found ground-nesting native bees that do not occur in much of the urban landscape because it is dominated by built surfaces and exotic flowering plants. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/366140/original/file-20201028-19-1dawhb3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Grasses, native flowers and trees at a golf course" src="https://images.theconversation.com/files/366140/original/file-20201028-19-1dawhb3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/366140/original/file-20201028-19-1dawhb3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/366140/original/file-20201028-19-1dawhb3.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/366140/original/file-20201028-19-1dawhb3.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/366140/original/file-20201028-19-1dawhb3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/366140/original/file-20201028-19-1dawhb3.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/366140/original/file-20201028-19-1dawhb3.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Golf courses have higher biodiversity than other green spaces in our cities.</span>
<span class="attribution"><span class="source">Nicholas Williams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The minimum number of bird species we saw on a golf course was always higher than the maximum numbers at other green spaces. We found much more evidence of birds breeding. There was also a diverse array of insect-eating birds, which are in decline in many parts of Australia. </p>
<p>Some golf courses supported all ten bat species known to occur in this part of metropolitan Melbourne. Bat activity was ten times greater than in nearby areas of housing. Golf courses also supported twice as many bat species considered “sensitive” to urbanisation. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-39-endangered-species-in-melbourne-sydney-adelaide-and-other-australian-cities-114741">The 39 endangered species in Melbourne, Sydney, Adelaide and other Australian cities</a>
</strong>
</em>
</p>
<hr>
<h2>Why is biodiversity greater on golf courses?</h2>
<p>There are many reasons golf courses support far more than the typical “urban-adapted” fauna we see in our cities. A key factor is the complex vegetation structure in the large parts of golf courses where you don’t want to hit your golf ball – the “rough” and “out of bounds” areas. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/367341/original/file-20201103-15-18inzyf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Looking from the golf tee across the fairway with trees either side." src="https://images.theconversation.com/files/367341/original/file-20201103-15-18inzyf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/367341/original/file-20201103-15-18inzyf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/367341/original/file-20201103-15-18inzyf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/367341/original/file-20201103-15-18inzyf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/367341/original/file-20201103-15-18inzyf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/367341/original/file-20201103-15-18inzyf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/367341/original/file-20201103-15-18inzyf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Golfers fear the rough, but local wildlife loves the densely vegetated areas near Dandenong Creek at Glen Waverley Golf Course.</span>
<span class="attribution"><span class="source">Nicholas Williams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>These areas of long grass and dense, often native, shrubs have little to no human intervention. These conditions are rarely found in urban parks and residential gardens, which typically have highly managed vegetation. The relatively high proportion of native plant species, many indigenous to the area, is also very important.</p>
<p>This complex vegetation is critical habitat for a wide array of animals such as small insect-eating birds, larger reptiles and ground-dwelling mammals. For example, occurrence records show Northcote Golf Course is an <a href="http://friendsofmerricreek.org.au/wp-content/uploads/2020/10/Newsletter_Nov20_Jan21.pdf">important refuge</a> for the small population of swamp wallabies living along Merri Creek in Melbourne’s inner north. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/367345/original/file-20201103-13-1eql3oe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Patch of heath next to golf course fairway" src="https://images.theconversation.com/files/367345/original/file-20201103-13-1eql3oe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/367345/original/file-20201103-13-1eql3oe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/367345/original/file-20201103-13-1eql3oe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/367345/original/file-20201103-13-1eql3oe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/367345/original/file-20201103-13-1eql3oe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/367345/original/file-20201103-13-1eql3oe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/367345/original/file-20201103-13-1eql3oe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Areas of heathland are rare in cities, but heathland species have a refuge at Spring Valley Golf Course.</span>
<span class="attribution"><span class="source">Nicholas Williams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Greater leaf litter accumulation and lower soil compaction mean these areas have healthier soils with more biological activity. These soils can also absorb stormwater more effectively, reducing the risk of urban flooding. </p>
<p>Another reason is that golf courses have many more large, old native trees. These mature trees are critical to the breeding success of hundreds of Australia’s animal species as they contain hollows, which are rare in urban areas. Because golf courses often prevent other uses, old trees can be left standing longer than is tolerated in other parts of the city. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/367342/original/file-20201103-17-1d10ec3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Trees along a golf fairway" src="https://images.theconversation.com/files/367342/original/file-20201103-17-1d10ec3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/367342/original/file-20201103-17-1d10ec3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/367342/original/file-20201103-17-1d10ec3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/367342/original/file-20201103-17-1d10ec3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/367342/original/file-20201103-17-1d10ec3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/367342/original/file-20201103-17-1d10ec3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/367342/original/file-20201103-17-1d10ec3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mature native trees provide critical habitat, including nesting hollows, for many species.</span>
<span class="attribution"><span class="source">Nicholas Williams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Another important factor is the exclusion of dogs and ability to control foxes and cats, which protects vulnerable fauna. </p>
<p>Golf courses also provide a large expanse of dark vegetated habitat in an otherwise illuminated landscape. This habitat is critical for nocturnal animals such as bats, as well as many birds and invertebrates. Artificial light at night is emerging as one of the most pervasive threats to urban wildlife. </p>
<p>Large refuges of dark habitat in cities are unique and ought to be protected. However, this may be at odds with increased human activity, particularly if night lighting is needed to satisfy <a href="https://www.theage.com.au/national/victoria/major-safety-audit-for-merri-creek-trail-following-shocking-alleged-rape-20191206-p53hj8.html">safety concerns</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/getting-smarter-about-city-lights-is-good-for-us-and-nature-too-69556">Getting smarter about city lights is good for us and nature too</a>
</strong>
</em>
</p>
<hr>
<h2>Shared use is possible but must be managed</h2>
<p>We are not suggesting golf courses should not be made more accessible to the public. The COVID-19 restrictions on human movement have highlighted the <a href="https://theconversation.com/our-cities-are-full-of-parks-so-why-are-we-looking-to-golf-courses-for-more-open-space-147559">value of urban green spaces</a> as places to exercise, socialise and connect with nature. But if city golf courses are opened to the public, it is vital it not be done at the expense of their biodiversity. </p>
<p>Indeed, shared-use models may ensure golf courses remain viable in Australian cities. Recognition of their biodiversity, cooling and social benefits via mechanisms such as council rate rebates could help ease the <a href="https://www.abc.net.au/news/2016-10-23/golf-on-the-hunt-for-new-members-after-tough-times/7957146">financial pressures of decreasing membership</a>. </p>
<p>The potential for golf course managers to improve the habitat that sustains biodiversity is also great. <a href="https://www.theage.com.au/culture/art-and-design/gardening-above-par-20200731-p55h96.html">Ways to achieve this</a> include tree planting, direct seeding of native grasses and wildflowers, and regeneration burns. Many course managers are eager to do this, although they have to proceed cautiously because it can affect the speed of play.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/367343/original/file-20201103-13-7mex45.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="revegetation area at golf course" src="https://images.theconversation.com/files/367343/original/file-20201103-13-7mex45.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/367343/original/file-20201103-13-7mex45.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/367343/original/file-20201103-13-7mex45.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/367343/original/file-20201103-13-7mex45.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/367343/original/file-20201103-13-7mex45.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/367343/original/file-20201103-13-7mex45.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/367343/original/file-20201103-13-7mex45.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Revegetation projects like this one at Woodlands Golf Club add even more value for wildlife.</span>
<span class="attribution"><span class="source">Nicholas Williams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Australian cities have some of the <a href="https://www.un.org/en/events/citiesday/assets/pdf/the_worlds_cities_in_2018_data_booklet.pdf">highest population growth</a> rates <a href="https://www.theage.com.au/national/victoria/melbourne-is-one-of-the-fastest-growing-cities-in-the-developed-world-20180920-p504zn.html">in the developed world</a>. This growth is <a href="https://theconversation.com/the-39-endangered-species-in-melbourne-sydney-adelaide-and-other-australian-cities-114741">putting pressure on our biodiversity</a>, decreasing human liveability and increasing conflict about the use of increasingly crowded green spaces. </p>
<p>Some urban golf courses <a href="https://www.abc.net.au/gardening/factsheets/beyond-the-rough/11481964">support threatened species and communities</a>, but all are biodiversity refuges in what can be a hostile urban landscape. We need to consider this when contemplating alternative uses.</p><img src="https://counter.theconversation.com/content/148634/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nicholas Williams has received funding from Hort Innovation, City of Melbourne, Australian Research Council, Australian Golf Course Superintendents Association and the Victorian Department of Environment, Land, Water and Planning. He is also the President of Friends of Merri Creek. </span></em></p><p class="fine-print"><em><span>The research presented in this article was funded by an Australian Research Council Linkage Project (LP110100686), in collaboration with Industry Partners: Australian Golf Course Superintendents Association and the Australian Research Centre for Urban Ecology, Royal Botanic Gardens Melbourne. The project ran from 2011-2014.</span></em></p><p class="fine-print"><em><span>Caragh Threlfall receives funding from the Clean Air and Urban Landscapes Hub, funded by the Australian Government’s National Environment Science Program; the City of Melbourne and the Australian Research Council through the Discovery Early Career Researcher Scheme (DE200101226). The research presented in this article was funded by an Australian Research Council Linkage Project (LP110100686), in collaboration with Industry Partners: Australian Golf Course Superintendents Association and the Australian Research Centre for Urban Ecology, Royal Botanic Gardens Melbourne. The project ran from 2011-2014.</span></em></p><p class="fine-print"><em><span>Stephen Livesley has received funding from Horticulture Innovations Australia, Melbourne Water, City West Water, Nursery and Garden Industry Australia and many local governments. The research presented in this article was funded by an Australian Research Council Linkage Project (LP110100686), in collaboration with Industry Partners: Australian Golf Course Superintendents Association and the Australian Research Centre for Urban Ecology, Royal Botanic Gardens Melbourne. The project ran from 2011-2014.</span></em></p>COVID-19 restrictions led to calls to open up golf courses to the public. But these are such precious refuges for native flora and fauna that access will have to be carefully managed.Nicholas Williams, Associate Professor in Urban Ecology and Urban Horticulture, The University of MelbourneAmy Hahs, Senior Lecturer In Urban Horticulture, The University of MelbourneCaragh Threlfall, ARC Discovery Early Career Research Fellow, School of Life and Environmental Sciences, University of SydneyStephen Livesley, Associate Professor in Urban Ecosystems, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1364792020-09-18T12:07:19Z2020-09-18T12:07:19ZMonarch butterflies’ spectacular migration is at risk – an ambitious new plan aims to help save it<figure><img src="https://images.theconversation.com/files/330844/original/file-20200427-145499-axj3ye.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4288%2C2843&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Monarch butterflies cover a tree at El Rosario Monarch Butterfly Sanctuary in Michoacán, Mexico.</span> <span class="attribution"><span class="source">D. André Green II</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>One of nature’s epic events is underway: Monarch butterflies’ fall migration. Departing from all across the United States and Canada, the butterflies travel up to 2,500 miles to cluster at the same locations in Mexico or along the Pacific Coast where their great-grandparents spent the previous winter. </p>
<p>Human activities have an outsized impact on monarchs’ ability to migrate yearly to these specific sites. Development, agriculture and logging have reduced monarch habitat. Climate change, drought and pesticide use also reduce the number of butterflies that complete the journey.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/356567/original/file-20200904-22-16c8ohd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map of North America showing monarch migration routes." src="https://images.theconversation.com/files/356567/original/file-20200904-22-16c8ohd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/356567/original/file-20200904-22-16c8ohd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=452&fit=crop&dpr=1 600w, https://images.theconversation.com/files/356567/original/file-20200904-22-16c8ohd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=452&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/356567/original/file-20200904-22-16c8ohd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=452&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/356567/original/file-20200904-22-16c8ohd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=567&fit=crop&dpr=1 754w, https://images.theconversation.com/files/356567/original/file-20200904-22-16c8ohd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=567&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/356567/original/file-20200904-22-16c8ohd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=567&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Monarch butterflies migrate south in fall and north in spring, traveling up to 2,500 miles.</span>
<span class="attribution"><a class="source" href="https://www.monarchwatch.org/blog/uploads/2010/05/monarchwatch-map-1200x903.jpg">MonarchWatch.org</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Since 1993, the area of forest covered by monarchs at their overwintering sites in Mexico has fallen from a peak of 45 acres in 1996-1997 to <a href="https://news.mongabay.com/2020/03/number-of-monarch-butterflies-wintering-in-mexico-down-by-more-than-half/">as low as 1.66 acres</a> in the winter of 2013-2014. A 2016 study warned that monarchs were dangerously close to a predicted “<a href="https://doi.org/10.1038/srep23265">point of no return</a>.” The 2019 count of monarchs in California was the lowest ever recorded for that group. </p>
<p>What was largely a bottom-up, citizen-powered effort to save the struggling monarch butterfly migration has shifted toward a top-down conversation between the federal government, private industry and large-tract landowners. As a <a href="https://greendeilab.com">biologist studying monarchs</a> to understand the <a href="https://doi.org/10.1111/mec.15178">molecular and genetic aspects of migration</a>, I believe this experiment has high stakes for monarchs and other imperiled species.</p>
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<h2>Millions of people care about monarchs</h2>
<p>I will never forget the sights and sounds the first time I visited monarchs’ overwintering sites in Mexico. Our guide pointed in the distance to what looked like hanging branches covered with dead leaves. But then I saw the leaves flash orange every so often, revealing what were actually thousands of tightly packed butterflies. The monarchs made their most striking sounds in the Sun, when they burst from the trees in massive fluttering plumes or landed on the ground in the tussle of mating.</p>
<p>Decades of educational outreach by teachers, researchers and hobbyists has cultivated a generation of monarch admirers who want to help preserve this phenomenon. This global network has helped restore not only monarchs’ summer breeding habitat by planting milkweed, but also general pollinator habitat by planting nectaring flowers across North America. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/337140/original/file-20200522-124845-3yb90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/337140/original/file-20200522-124845-3yb90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/337140/original/file-20200522-124845-3yb90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=346&fit=crop&dpr=1 600w, https://images.theconversation.com/files/337140/original/file-20200522-124845-3yb90.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=346&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/337140/original/file-20200522-124845-3yb90.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=346&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/337140/original/file-20200522-124845-3yb90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=435&fit=crop&dpr=1 754w, https://images.theconversation.com/files/337140/original/file-20200522-124845-3yb90.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=435&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/337140/original/file-20200522-124845-3yb90.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=435&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 monarch butterfly in a Toronto park on common milkweed, an important plant for its survival.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/12th-2012-pics-of-monarch-butterfly-on-common-milkweed-news-photo/165292836?adppopup=true">Colin McConnell/Toronto Star via Getty Images</a></span>
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<p>Scientists have calculated that restoring the monarch population to a stable level of about 120 million butterflies will require <a href="https://doi.org/10.1111/icad.12198">planting 1.6 billion new milkweed stems</a>. And they need them fast. This is too large a target to achieve through grassroots efforts alone. A <a href="https://www.fws.gov/savethemonarch/CCAA.html">new plan</a>, announced in the spring of 2020, is designed to help fill the gap.</p>
<h2>Pros and cons of regulation</h2>
<p>The top-down strategy for saving monarchs gained energy in 2014, when the U.S. Fish and Wildlife Service <a href="https://www.fws.gov/southeast/pdf/petition/monarch.pdf">proposed</a> listing them as threatened under the Endangered Species Act. A decision is expected in December 2020.</p>
<p>Listing a species as endangered or threatened <a href="https://www.fws.gov/endangered/esa-library/pdf/listing.pdf">triggers restrictions</a> on “taking” (hunting, collecting or killing), transporting or selling it, and on activities that negatively affect its habitat. Listing monarchs would impose restrictions on landowners in areas where monarchs are found, over vast swaths of land in the U.S.</p>
<p>In my opinion, this is not a reason to avoid a listing. However, a “threatened” listing might inadvertently threaten one of the best conservation tools that we have: public education. </p>
<p>It would severely restrict common practices, such as rearing monarchs in classrooms and back yards, as well as scientific research. Anyone who wants to take monarchs and milkweed for these purposes would have to apply for special permits. But these efforts have had a multigenerational educational impact, and they should be protected. Few public campaigns have been more successful at raising awareness of conservation issues.</p>
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<figcaption><span class="caption">University of Michigan biologist D. Andre Green studies monarch butterflies’ DNA to understand what drives their incredible migration.</span></figcaption>
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<h2>The rescue attempt</h2>
<p>To preempt the need for this kind of regulation, the U.S. Fish and Wildlife Service approved a <a href="https://www.fws.gov/savethemonarch/pdfs/Monarch%20CCAA-CCA%20Public%20Comment%20Documents/Monarch-Nationwide_CCAA-CCA_Draft.pdf">Nationwide Candidate Conservation Agreement for Monarch Butterflies</a>. Under this plan, “rights-of-way” landowners – energy and transportation companies and private owners – commit to restoring and creating millions of acres of pollinator habitat that have been decimated by land development and herbicide use in the past half-century. </p>
<p>The agreement was spearheaded by the <a href="http://rightofway.erc.uic.edu">Rights-of-Way Habitat Working Group</a>, a collaboration between the University of Illinois Chicago’s <a href="https://erc.uic.edu/">Energy Resources Center</a>, the Fish and Wildlife Service and over 40 organizations from the energy and transportation sectors. These sectors control “rights-of-way” corridors such as lands near power lines, oil pipelines, railroad tracks and interstates, all valuable to monarch habitat restoration.</p>
<p>Under the plan, partners voluntarily agree to commit a percentage of their land to host protected monarch habitat. In exchange, general operations on their land that might directly harm monarchs or destroy milkweed will not be subject to the enhanced regulation of the Endangered Species Act – protection that would last for 25 years if monarchs are listed as threatened. The agreement is expected to create up to 2.3 million acres of new protected habitat, which ideally would avoid the need for a “threatened” listing.</p>
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<p>Many questions remain. Scientists are still learning about factors that cause monarch population decline, so it is likely that land management goals will need to change over the course of the agreement, and partner organizations will have to adjust to those changes.</p>
<p>Oversight of the plan will fall primarily to the University of Illinois, and ultimately to the U.S. Fish & Wildlife Service. But it’s not clear whether they will have the resources they need. And without effective oversight, the plan could allow parties to carry out destructive land management practices that would otherwise be barred under an Endangered Species Act listing.</p>
<h2>A model for collaboration</h2>
<p>This agreement could be one of the few specific interventions that is big enough to allow researchers to quantify its impact on the size of the monarch population. Even if the agreement produces only 20% of its 2.3 million acre goal, this would still yield nearly half a million acres of new protected habitat. This would provide a powerful test of the role of declining breeding and nectaring habitat compared to other challenges to monarchs, such as climate change or pollution.</p>
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<p>Scientists hope that data from this agreement will be made publicly available, like projects in the <a href="https://www.fws.gov/savethemonarch/MCD.html">Monarch Conservation Database</a>, which has tracked smaller on-the-ground conservation efforts since 2014. With this information we can continue to develop powerful new models with better accuracy for determining how different habitat factors, such as the number of milkweed stems or nectaring flowers on a landscape scale, affect the monarch population.</p>
<p>North America’s monarch butterfly migration is one of the most awe-inspiring feats in the natural world. If this rescue plan succeeds, it could become a model for bridging different interests to achieve a common conservation goal.</p><img src="https://counter.theconversation.com/content/136479/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>D. André Green II receives funding from the National Geographic Society.</span></em></p>Can a plan that brings together government and private landowners create enough habitat for monarch butterflies?D. André Green II, Assistant Professor of Ecology and Evolutionary Biology, University of MichiganLicensed as Creative Commons – attribution, no derivatives.