tag:theconversation.com,2011:/us/topics/dunnart-67894/articlesDunnart – The Conversation2023-03-26T19:12:21Ztag:theconversation.com,2011:article/2006322023-03-26T19:12:21Z2023-03-26T19:12:21ZI realised the fat-tailed dunnart was under threat. Here’s how I got the species officially listed<figure><img src="https://images.theconversation.com/files/517348/original/file-20230324-16-j0scpt.jpg?ixlib=rb-1.1.0&rect=49%2C0%2C5472%2C3637&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Caleb McElrea</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Saving endangered species is an uphill battle in Australia, the <a href="https://theconversation.com/gut-wrenching-and-infuriating-why-australia-is-the-world-leader-in-mammal-extinctions-and-what-to-do-about-it-192173">mammal extinction capital</a> of the world. But the first step, threatened species listing, can be confusing, tedious and time-consuming. </p>
<p>To demystify the rigorous (yet arduous) process for listing threatened species, we describe the experience of listing fat-tailed dunnarts in Victoria. </p>
<p>This feisty little predator stores fat in its tail, much like a camel’s hump. For too long it was considered common, but evidence shows the species is in decline and needs help to recover. </p>
<p>Threatened species listing affords extra protection, but there are no guarantees. We need to keep the pressure on policy-makers and public servants to ensure our most vulnerable species receive the protection they deserve. </p>
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Read more:
<a href="https://theconversation.com/gut-wrenching-and-infuriating-why-australia-is-the-world-leader-in-mammal-extinctions-and-what-to-do-about-it-192173">'Gut-wrenching and infuriating': why Australia is the world leader in mammal extinctions, and what to do about it</a>
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<figure class="align-center ">
<img alt="A litter of fat-tailed dunnart joeys nesting in straw." src="https://images.theconversation.com/files/517355/original/file-20230324-16-mdnoy8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/517355/original/file-20230324-16-mdnoy8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=552&fit=crop&dpr=1 600w, https://images.theconversation.com/files/517355/original/file-20230324-16-mdnoy8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=552&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/517355/original/file-20230324-16-mdnoy8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=552&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/517355/original/file-20230324-16-mdnoy8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=693&fit=crop&dpr=1 754w, https://images.theconversation.com/files/517355/original/file-20230324-16-mdnoy8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=693&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/517355/original/file-20230324-16-mdnoy8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=693&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Fat-tailed dunnarts are short lived, which means successful breeding is important for populations to survive.</span>
<span class="attribution"><span class="source">Emily Scicluna</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>A shameful record of extinction</h2>
<p>Australia has the highest <a href="https://www.abc.net.au/news/2015-08-19/fact-check-does-australia-have-one-of-the-highest-extinction/6691026">mammal extinction rate</a> in the world. We have lost 39 land mammals since European settlement. That’s a rate of about <a href="https://www.pnas.org/doi/10.1073/pnas.1417301112#:%7E:text=Extinctions%20in%20the%20Australian%20land,1">one to two mammal species per decade</a> since the first post-1788 Australian mammal extinction, probably in the 1840s.</p>
<p>In total, 67 animals and 37 plants are declared extinct under the federal Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). That includes 39 mammals, 22 birds, four frogs, one reptile and one earthworm. </p>
<p>A further <a href="https://www.environment.gov.au/cgi-bin/sprat/public/publicthreatenedlist.pl?wanted=fauna">499 animals</a> and <a href="https://www.environment.gov.au/cgi-bin/sprat/public/publicthreatenedlist.pl?wanted=flora">1,374 plants</a> are listed as threatened with extinction. </p>
<p>Threatened species listing gives the conservation status legal standing and mandates actions to secure species populations, allowing eventual removal from the list. This may include developing a recovery plan that stipulates actions to reduce threats (such as habitat loss, predation, or competition with invasive species) or to increase populations (such as captive breeding and translocations). </p>
<p>Listing also triggers environmental laws. Proposed developments that might harm or otherwise impact threatened species or their habitat should be referred for assessment under the EPBC Act. The development may be stopped entirely (although this rarely happens), modified to reduce potential impacts, or offsets may be required to compensate by helping the species at another location. </p>
<h2>Cause for confusion</h2>
<p>A species at risk of extinction may be listed as threatened under either state or federal legislation. However, there are several aspects of the listing process that may cause confusion. </p>
<p>The International Union for Conservation of Nature (IUCN) <a href="https://www.iucnredlist.org/">Red List</a> of Threatened Species has five <a href="http://cmsdocs.s3.amazonaws.com/keydocuments/summary_sheet_en_web.pdf">criteria</a>:</p>
<ul>
<li>A: population size reduction </li>
<li>B: geographic range (declining area or extent) </li>
<li>C: small population size and decline </li>
<li>D: very small or restricted population </li>
<li>E: quantitative analysis (reflecting the population’s viability). </li>
</ul>
<p>Each criterion has specific thresholds that a species must fall below to be considered threatened. However, a species only needs to meet one of the five criteria to be eligible for listing as threatened. </p>
<p>The catch-all term “threatened” includes different levels of extinction risk, from vulnerable through to endangered, critically endangered, extinct in the wild, and finally, extinct. The risk of extinction increases with each step. </p>
<p>For example, a species is classified as vulnerable if it has suffered a 30% reduction in population size over ten years or three generations. If the decline was 50% or more, it is classified as endangered, and critically endangered if the decline was greater than 80%. </p>
<p>Similarly, a species is vulnerable if its entire population consists of less than 1,000 adults, endangered if it is fewer than 250 adults, and critically endangered if less than 50 adults. </p>
<p>To further complicate matters, every state and territory, and the Commonwealth, has its own threatened species legislation. This means a species can potentially be listed as threatened in one jurisdiction but not in another. </p>
<p>For example, koalas are listed as threatened under the federal EPBC Act (due to drastic declines in NSW, Queensland and the ACT) but not under Victoria’s Flora and Fauna Guarantee Act. So a species can be threatened in one state but not in another, and can be threatened at the state level but not at a national level. </p>
<p>Finally, someone (or usually a group of people) must take the time and effort to formally nominate a species as threatened. While anyone can nominate a species for listing, the nominator must provide compelling evidence that the species satisfies at least one of the IUCN criteria. </p>
<p>This is not a trivial undertaking, so the official lists of threatened species are almost certainly an underestimate of the true number of species that are threatened. But this is exactly what I did. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/517349/original/file-20230324-16-nr74wu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A fat-tailed dunnart leaps down from a log to the ground, the fat tail is close to a person's hand for size comparison." src="https://images.theconversation.com/files/517349/original/file-20230324-16-nr74wu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/517349/original/file-20230324-16-nr74wu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/517349/original/file-20230324-16-nr74wu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/517349/original/file-20230324-16-nr74wu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/517349/original/file-20230324-16-nr74wu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/517349/original/file-20230324-16-nr74wu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/517349/original/file-20230324-16-nr74wu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The tail of the fat-tailed dunnart contains body fat, stored when food is plentiful. This can give the tail a swollen appearance when times are good.</span>
<span class="attribution"><span class="source">Caleb McElrea</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Listing the fat-tailed dunnart</h2>
<p>Early in my PhD candidature (in February 2018), my goal was to use fat-tailed dunnarts as a model species for some of their more endangered relatives, such as the Tasmanian devil or eastern quoll.</p>
<p>The fat-tailed dunnart is a small, carnivorous, nocturnal marsupial that weighs around 15 grams (about the size of three grapes). They are incredibly cute, ferocious predators (of insects, that is) who store energy reserves in their tail, much like a camel’s hump. </p>
<p>The species is widely distributed across southern and central Australia in a range of habitats. In Victoria, they are largely confined to grasslands and open woodlands. </p>
<p>When I began my PhD research, fat-tailed dunnarts were assumed to be “common”, based on historical records. But no-one was really looking for them. So when I set out to find them, I couldn’t. </p>
<p>My main study site was at the Werribee Western Treatment Plant. In the early 1970s, 700 fat-tailed dunnart were trapped there over four years. Using the same methods, with double the survey effort, <a href="https://bioone.org/journals/australian-journal-of-zoology/volume-69/issue-2/ZO21014/Fat-tailed-dunnarts-Sminthopsis-crassicaudata-of-the-Werribee-grasslands/10.1071/ZO21014.full">I found none</a>. </p>
<p>In the intervening 43 years, 75% of suitable dunnart habitat at this site had been cleared. When I extended my search further west into Victoria’s grasslands, fat-tailed dunnarts were still present but only in very low numbers. As the last remaining small mammal in Victoria’s grasslands, this was highly concerning. </p>
<p>Over time I realised that this species was a threatened species in its own right. </p>
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Read more:
<a href="https://theconversation.com/these-historic-grasslands-are-becoming-a-weed-choked-waste-it-could-be-one-of-the-worlds-great-parks-144208">These historic grasslands are becoming a weed-choked waste. It could be one of the world's great parks</a>
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<h2>Gathering the evidence</h2>
<p>In 2019, I began to pursue statutory listing and protection for fat-tailed dunnarts in Victoria under the Flora and Fauna Guarantee Act. So what did that involve? </p>
<p>I needed to provide the following:</p>
<ul>
<li><p>Species description, life history, generation length, habitat, and distribution. Basically, everything there is to know about the species. Generation length is crucial: if a species has slow reproductive rates, it will be more difficult to recover from population crashes.</p></li>
<li><p>Key threats. I needed to provide evidence that fat-tailed dunnarts were experiencing habitat loss (conversion of grasslands to crops), being heavily preyed upon by invasive species (mostly by rats) and that the remaining populations were becoming geographically isolated, therefore restricting gene flow.</p></li>
<li><p>Evidence of decline. This is where it gets really tricky. I needed to provide evidence that fat-tailed dunnarts met at least one of the five IUCN criteria mentioned above. This was challenging because there were no long-term survey datasets available for fat-tailed dunnarts. How do you show a decline when no one knew what the original populations were? </p></li>
</ul>
<p>I was able to garner enough data and evidence from my PhD research, the <a href="https://bie.ala.org.au/species/https:/biodiversity.org.au/afd/taxa/86ab9ebf-cbd1-49f8-9786-312407738477">Atlas of Living Australia</a>, and compiling incidental recordings of this species from other surveys to convince the Scientific Advisory Committee to support the nomination of the fat-tailed dunnart.</p>
<p>Specifically, I was able to show that the Victorian population had declined by more than 60% from 2000-09 to 2010-19. This satisfied the threshold for population decline (criterion A) of at least 30% over the past 10 years (vulnerable). </p>
<p>I was also able to demonstrate that fat-tailed dunnarts now only occupied 1,427 square kilometres in Victoria, meeting the threshold for vulnerable under criterion B (geographic range). I satisfied not one, but two IUCN criteria.</p>
<figure class="align-center ">
<img alt="Emily Scicluna holding a fat-tailed dunnart" src="https://images.theconversation.com/files/517345/original/file-20230324-20-cfiq1p.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/517345/original/file-20230324-20-cfiq1p.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/517345/original/file-20230324-20-cfiq1p.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/517345/original/file-20230324-20-cfiq1p.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/517345/original/file-20230324-20-cfiq1p.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/517345/original/file-20230324-20-cfiq1p.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/517345/original/file-20230324-20-cfiq1p.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">Emily Scicluna successfully nominated the fat-tailed dunnart for threatened species listing in Victoria.</span>
<span class="attribution"><span class="source">La Trobe University</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Protecting the dunnart</h2>
<p>Once the vulnerable listing is formally ratified, planning decisions that involve clearing potential fat-tailed dunnart habitat need to consider the species. At least that’s the idea. In practice, legislative protection <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/csp2.12860">does not always translate to on-ground protection</a>. </p>
<p><a href="https://theconversation.com/environment-laws-have-failed-to-tackle-the-extinction-emergency-heres-the-proof-122936">Loopholes</a>, offsets, ministerial discretion and findings of “<a href="https://www.abc.net.au/news/2023-03-07/planned-perth-surf-park-in-jandakot-clears-environmental-hurdle/102061948">low to moderate impact</a>” mean projects that clear threatened species habitat go ahead more often than not. </p>
<p>Despite <a href="https://theconversation.com/labors-plan-to-save-threatened-species-is-an-improvement-but-its-still-well-short-of-what-we-need-191845">promising signals and intent from the federal government</a>, threatened species habitat continues to be cleared at alarming rates, pushing species towards the brink of extinction. The process for listing threatened species is rigorous - as it should be - but it is a means to an end. </p>
<p>Unless threatened species laws are enforced and strengthened, the effort required to have a species listed as threatened will be in vain. </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/australias-next-government-must-tackle-our-collapsing-ecosystems-and-extinction-crisis-182048">Australia's next government must tackle our collapsing ecosystems and extinction crisis</a>
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<img src="https://counter.theconversation.com/content/200632/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>Ever wondered what it takes to get on the threatened species list? This explainer demystifies the rigorous process, using the cute little predator that stores energy in its tail as an example.Emily Scicluna, Research Associate – Thylacine Integrated Genomic Restoration Research Laboratory, University of Melbourne, The University of MelbourneJim Radford, Associate Professor, La Trobe UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1851332022-06-16T19:54:31Z2022-06-16T19:54:31ZThis critically endangered marsupial survived a bushfire – then along came the feral cats<figure><img src="https://images.theconversation.com/files/469124/original/file-20220616-13059-uanvqm.jpg?ixlib=rb-1.1.0&rect=252%2C126%2C2224%2C1660&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">WWF Australia</span></span></figcaption></figure><p>The Black Summer bushfires of 2019-20 pushed a host of threatened species closer to extinction, including the critically endangered Kangaroo Island dunnart. And as <a href="https://www.nature.com/articles/s41598-022-11383-6">our research</a> released today shows, feral cats posed a second lethal threat to the species in the weeks after the disaster.</p>
<p>The <a href="https://www.awe.gov.au/environment/biodiversity/threatened/species/20-mammals-by-2020/kangaroo-island-dunnart">Kangaroo Island dunnart</a> is a mouse-sized marsupial found only on the western end of the island. Bushfires in January 2020 burnt more than 98% of its habitat. The dunnart population was thought to be about 500 before the fire; its current numbers are being surveyed but are thought to have since declined even further.</p>
<p>Cat predation has caused the extinction or near-extinction of several native species around the globe. Our results confirm for the first time that feral cats prey on the dunnart and did so directly after the bushfires.</p>
<p>The findings underscore the importance of acting immediately to protect threatened species from predators in the wake of catastrophic natural events.</p>
<figure class="align-center ">
<img alt="landscape turned to ash after fire" src="https://images.theconversation.com/files/469130/original/file-20220616-21-4thjt0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/469130/original/file-20220616-21-4thjt0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/469130/original/file-20220616-21-4thjt0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/469130/original/file-20220616-21-4thjt0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/469130/original/file-20220616-21-4thjt0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/469130/original/file-20220616-21-4thjt0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/469130/original/file-20220616-21-4thjt0.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 Kangaroo Island fires burnt 98% of dunnart habitat.</span>
<span class="attribution"><span class="source">David Mariuz/AAP</span></span>
</figcaption>
</figure>
<h2>Analysing feral cat diets</h2>
<p>Before the Black Summer fires, the Kangaroo Island dunnart’s habitat was fragmented due to land clearing and other pressures. Feral cats on the island were also suspected of contributing to the species decline, but this had not been proven.</p>
<p>A federally funded feral cat eradication program has been in place since 2015, and aims to make Kangaroo Island free of feral cats by 2030. </p>
<p>A 2020 <a href="http://www.publish.csiro.au/wr/WR19137">study</a> estimated there were between 1,000 and 2,300 feral cats on Kangaroo Island. We set out to determine whether cats threatened the dunnart.</p>
<p>We analysed the diet of feral cats humanely euthanised immediately after the 2019 bushfire. We accessed the stomach contents and digestive tracts of 86 cats captured between February and August 2020. </p>
<p>The cats were not killed for our study, but as part of the national feral cat control program and were euthanised in accordance with South Australia animal welfare laws. They were caught in unburnt areas where dunnarts and other species that survived the fire would likely have sought refuge.</p>
<p>We identified 263 distinct prey items in the cats’ stomachs and digestive tracts. They comprised:</p>
<ul>
<li>195 mammals</li>
<li>46 birds</li>
<li>10 reptiles</li>
<li>12 arthropods (invertebrates such as beetles).</li>
</ul>
<p>Among them, the introduced house mouse represented the most significant proportion, being part of the diet for 47 cats. </p>
<p>We found the remains of eight Kangaroo Island dunnarts in seven different cats. Three dunnarts were readily identifiable as they were nearly whole carcasses. Five more were identified based on hair features. </p>
<p>We observed dunnart tissue in both the stomach and large intestine of one cat, suggesting it had recently preyed on at least two individuals.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/from-kangaroo-island-to-mallacoota-citizen-scientists-proved-vital-to-australias-bushfire-recovery-48230">From Kangaroo Island to Mallacoota, citizen scientists proved vital to Australia's bushfire recovery</a>
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<figure class="align-center ">
<img alt="small furry animal in leaves" src="https://images.theconversation.com/files/469125/original/file-20220616-21-8d53wj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/469125/original/file-20220616-21-8d53wj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/469125/original/file-20220616-21-8d53wj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/469125/original/file-20220616-21-8d53wj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/469125/original/file-20220616-21-8d53wj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/469125/original/file-20220616-21-8d53wj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/469125/original/file-20220616-21-8d53wj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Researchers found the remains of eight dunnarts in seven different cats.</span>
<span class="attribution"><span class="source">WWF</span></span>
</figcaption>
</figure>
<p>Our results confirm for the first time that feral cats prey on Kangaroo Island dunnarts and were efficient hunters of this species directly after the fires.</p>
<p>Our results provides only a small snapshot of what the feral cat had eaten. That’s because once the prey is fully digested (between 27 and 36 hours after being caught) we cannot analyse it. So the cats may well have recently consumed more prey than we could identify.</p>
<p>Safe to say, the cats present a substantial threat to the dunnart. We also found the remains of the endangered southern brown bandicoot in a male cat’s stomach. This endangered species is likely the last out of eight native bandicoot species still living in the wild in South Australia. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/australian-endangered-species-kangaroo-island-dunnart-20841">Australian endangered species: Kangaroo Island Dunnart</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="cat carries animal in mouth" src="https://images.theconversation.com/files/469126/original/file-20220616-11875-57qce4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/469126/original/file-20220616-11875-57qce4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/469126/original/file-20220616-11875-57qce4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/469126/original/file-20220616-11875-57qce4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/469126/original/file-20220616-11875-57qce4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/469126/original/file-20220616-11875-57qce4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/469126/original/file-20220616-11875-57qce4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cat predation has caused the extinction or near-extinction of several native species around the globe.</span>
<span class="attribution"><span class="source">University of Tasmania</span></span>
</figcaption>
</figure>
<h2>Saving the most vulnerable</h2>
<p>The Kangaroo Island dunnart is emblematic of challenges faced by threatened species across the world – especially those confined to increasingly fragmented habitats, coping with the catastrophic consequences of climate change and preyed on by introduced species. </p>
<p>Species already compromised can easily slide into extinction after disasters such as the Black Summer fires – the likes of which are predicted to become more frequent as the world warms and dries. </p>
<p>After such events, we must act immediately to protect vulnerable species from invasive predators. These measures can mean the difference between survival and extinction.</p>
<p>But prevention is better than cure, and we should not wait until after a catastrophic event to protect our most threatened fauna.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/im-searching-firegrounds-for-surviving-kangaroo-island-micro-trapdoor-spiders-6-months-on-im-yet-to-find-any-139556">I'm searching firegrounds for surviving Kangaroo Island Micro-trapdoor spiders. 6 months on, I'm yet to find any</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/185133/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Louis Lignereux receives funding from Human Frontier Science Programme (Grant RGP0062/2018) </span></em></p>The findings underscore the importance of acting immediately to protect threatened species from predators in the wake of catastrophic natural events.Louis Lignereux, Researcher, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1464092020-12-29T20:40:16Z2020-12-29T20:40:16ZTorpor: a neat survival trick once thought rare in Australian animals is actually widespread<figure><img src="https://images.theconversation.com/files/360952/original/file-20200930-22-1iez5gv.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C6016%2C4016&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>Life is hard for small animals in the wild, but they have many solutions to the challenges of their environment. One of the most fascinating of these strategies is torpor. Not, to be confused with sleep or Sunday afternoon lethargy, torpor is a complex response to the costs of living. </p>
<p>To enter torpor, an animal decreases its metabolism, reducing its energy requirements. A torpid animal will often be curled in a tight ball in its nest and look like it’s sleeping.</p>
<p>Once thought to occur only in birds and mammals in the Northern Hemisphere where winters are more pronounced, we now know torpor is <a href="https://publications.rzsnsw.org.au/doi/abs/10.7882/AZ.2010.009">widespread</a> in small Australian mammals, and has also been observed in many small Australian bird species. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360944/original/file-20200930-18-qcv9gh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An echidna in the bush." src="https://images.theconversation.com/files/360944/original/file-20200930-18-qcv9gh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360944/original/file-20200930-18-qcv9gh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=377&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360944/original/file-20200930-18-qcv9gh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=377&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360944/original/file-20200930-18-qcv9gh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=377&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360944/original/file-20200930-18-qcv9gh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=474&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360944/original/file-20200930-18-qcv9gh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=474&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360944/original/file-20200930-18-qcv9gh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=474&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Echidnas use torpor to save energy.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/animal-response-to-a-bushfire-is-astounding-these-are-the-tricks-they-use-to-survive-129327">Animal response to a bushfire is astounding. These are the tricks they use to survive</a>
</strong>
</em>
</p>
<hr>
<h2>Masters of metabolism</h2>
<p>Birds and mammals are endotherms and can maintain a high and constant body temperature independent of the environmental temperature, thanks to their high metabolic rate. This allows them to be active across a wide range of environments. </p>
<p>The downside? This high metabolic rate requires a lot of food to fuel it. By reducing the metabolism in a very controlled manner and entering torpor, an animal can live on less energy. </p>
<p>With a lower metabolic rate, the animal’s body temperature decreases — sometimes by as much as 30°C. How low it goes can depend on the extent of the metabolic reduction and the temperature of animal’s immediate environment. The reduced body temperature further lowers the metabolic rate.</p>
<h2>Slowing down to survive</h2>
<p>Torpor is an extremely effective survival strategy for small endotherms. For example, small mammals have been observed <a href="https://royalsocietypublishing.org/doi/full/10.1098/rsbl.2015.0134">using torpor after bushfires</a>. </p>
<p>Take the brown antechinus, for example. When other animals have fled, this 30g marsupial hides in refuges, waits out the fire, then uses torpor to cope with reduced food availability until local vegetation and invertebrate populations recover. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360942/original/file-20200930-14-167f4a6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A brown antechinus on a tree." src="https://images.theconversation.com/files/360942/original/file-20200930-14-167f4a6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360942/original/file-20200930-14-167f4a6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=421&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360942/original/file-20200930-14-167f4a6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=421&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360942/original/file-20200930-14-167f4a6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=421&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360942/original/file-20200930-14-167f4a6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=530&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360942/original/file-20200930-14-167f4a6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=530&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360942/original/file-20200930-14-167f4a6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=530&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 brown antechinus uses torpor to cope with reduced food availability after bushfire.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Many pregnant and lactating bats and <a href="https://academic.oup.com/icb/article/54/3/516/2797887">marsupials</a>, and even the <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0006070">echidna</a>, synchronise torpor with reproduction to cope with the energetic costs of mating, pregnancy or lactation. </p>
<p>There are two main types of torpor: daily torpor and hibernation. </p>
<h2>Daily torpor</h2>
<p>Animals that use daily torpor can do so for approximately 3-6 hours a day as needed.</p>
<p>Daily torpor is common in, but not exclusive to, endotherms living in arid areas, such as the fat-tailed dunnart. This species is a carnivorous marsupial and has a <a href="https://link.springer.com/article/10.1007/s00114-007-0293-4">diet</a> of insects and other invertebrates, which may be in short supply in winter. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360948/original/file-20200930-22-h9ene3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A fat-tailed dunnart." src="https://images.theconversation.com/files/360948/original/file-20200930-22-h9ene3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360948/original/file-20200930-22-h9ene3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=378&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360948/original/file-20200930-22-h9ene3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=378&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360948/original/file-20200930-22-h9ene3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=378&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360948/original/file-20200930-22-h9ene3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=475&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360948/original/file-20200930-22-h9ene3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=475&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360948/original/file-20200930-22-h9ene3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=475&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">When finding enough food is difficult, the fat-tailed dunnart uses torpor.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Weighing approximately 12 grams as adults, the fat-tailed dunnart may need to eat its body weight in food each day. When finding enough food is difficult, it uses torpor; foraging in the early part of the night then entering torpor in the early morning. Fat-tailed dunnarts reduce their metabolic rate, and subsequently their body temperature, from 35 °C to approximately 15°C, or the temperature of their underground nest.</p>
<h2>Hibernation</h2>
<p>Animals that hibernate lower their metabolic rate further and have longer torpor bouts than those that use daily torpor. An example of an Australian hibernator is the eastern pygmy possum, a 40g marsupial found in south eastern Australia that hibernates regularly, decreasing its body temperature from approximately 35 °C to as low as 5°C. </p>
<p>When active, this species can <a href="https://link.springer.com/article/10.1007/s00114-007-0274-7?con=&dom=pscau&src=syndication">survive for less than half a day</a> on 1g of fat, but when hibernating, it can survive for two weeks. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/359702/original/file-20200924-13-wk5n4g.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/359702/original/file-20200924-13-wk5n4g.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/359702/original/file-20200924-13-wk5n4g.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/359702/original/file-20200924-13-wk5n4g.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/359702/original/file-20200924-13-wk5n4g.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/359702/original/file-20200924-13-wk5n4g.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/359702/original/file-20200924-13-wk5n4g.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/359702/original/file-20200924-13-wk5n4g.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A torpid eastern pygmy possum. Note the curled posture.</span>
<span class="attribution"><span class="source">Photo credit: Chris Wacker</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>If it weren’t for the periodic increases in metabolic rate and body temperature, a hibernating pygmy possum could live for well over three months on 1g of fat. However, the exact purpose of these periodic arousals is unknown. </p>
<p>The metabolic rate during pygmy possum hibernation is just 2% of the minimum metabolic rate endotherms at a normal body temperature need to live. This baseline metabolism is called basal metabolic rate. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360945/original/file-20200930-22-1weulat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An American black bear" src="https://images.theconversation.com/files/360945/original/file-20200930-22-1weulat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360945/original/file-20200930-22-1weulat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360945/original/file-20200930-22-1weulat.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360945/original/file-20200930-22-1weulat.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360945/original/file-20200930-22-1weulat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360945/original/file-20200930-22-1weulat.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360945/original/file-20200930-22-1weulat.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">Black bears can’t hibernate with a lower body temperature.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Compare this with a well-known hibernator, the <a href="https://science.sciencemag.org/content/331/6019/906.abstract?casa_token=AZwPQmQ0w9QAAAAA:zDNkBqJWQo5VURWXpZ1tavfjXYVPcJxwPahYWRpOva9kCJaXp5EY4y3Jo3JNmNS4fHLtMpLaB3hTP7s">American black bear</a>.</p>
<p>At approximately 120kg, its metabolic rate during hibernation decreases to 25% of the basal metabolic rate, and the body temperature decreases from approximately 37°C to 30 °C. Black bears can’t hibernate with a lower body temperature, perhaps because it would take them a very long time to reduce it, and then cost them too much energy to rewarm at the end of hibernation.</p>
<h2>Can humans do it?</h2>
<p>The question people often ask about torpor, is “can humans do it?” Interestingly, some small <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/evan.21588?casa_token=u8I8ehxWRq0AAAAA%3ACiJacjM8jdzhJdC74EKZHznxZOXPqiR5t5LegoIvkg2FeMc6DGglQ5E3p3W0u2YoCpPmwdK9Aml20NM">primates have been observed using torpor</a>. While it is technically possible to induce torpor in humans chemically, torpor is a very complex physiological process, and there are many aspects of it scientists still don’t fully understand. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/360947/original/file-20200930-22-152k6b1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A gray mouse lemur in Madagascar." src="https://images.theconversation.com/files/360947/original/file-20200930-22-152k6b1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360947/original/file-20200930-22-152k6b1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360947/original/file-20200930-22-152k6b1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360947/original/file-20200930-22-152k6b1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360947/original/file-20200930-22-152k6b1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360947/original/file-20200930-22-152k6b1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360947/original/file-20200930-22-152k6b1.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">The grey mouse lemur in Madagascar is among the primates that uses torpor.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Coping with climate change</h2>
<p>Australia’s wildlife have evolved strategies to cope with life in an often-harsh environment affected by multiple year-long droughts, landscape-altering floods, and widespread bushfires.</p>
<p>Climate change is predicted to increase the duration, frequency and severity of these events, and in conjunction with landscape clearing, animals are facing new environmental and resource challenges. </p>
<p>While animals that use flexible, daily torpor may be well-suited to cope during these times, at least in the short term, hibernators that depend on long winters are most at risk. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/summer-bushfires-how-are-the-plant-and-animal-survivors-6-months-on-we-mapped-their-recovery-142551">Summer bushfires: how are the plant and animal survivors 6 months on? We mapped their recovery</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/146409/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Wacker has received funding through Australian Geographic for a study in Kosciuszko National Park.
</span></em></p>Once thought to occur only in birds and mammals in the Northern Hemisphere, due to the more pronounced winters, we now know torpor is widespread in small Australian mammals.Chris Wacker, Postdoctoral Research Fellow - School of Environmental and Rural Science, University of New EnglandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1412012020-07-13T20:03:52Z2020-07-13T20:03:52ZFire-ravaged Kangaroo Island is teeming with feral cats. It’s bad news for this little marsupial<figure><img src="https://images.theconversation.com/files/347027/original/file-20200713-30-1lod1f7.jpg?ixlib=rb-1.1.0&rect=13%2C22%2C2982%2C1971&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">AAP Image/Supplied by WWF-Australia</span></span></figcaption></figure><p>When I visited Kangaroo Island for the first time after the summer bushfires, I thought I knew what to expect. But what really hit me was the scale. </p>
<p>The wild western end of the island, once a vast mallee woodland peppered with wildflowers and mobs of roaming roos, had been completely erased. An immense dune field covered with sharp blackened sticks now stretched beyond the horizon, to the sea, hollow and quiet.</p>
<p>While fire is a fundamental process in many Australian ecosystems, the size and severity of this fire was extreme, and the impacts on the island’s wildlife has been immense.</p>
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Read more:
<a href="https://theconversation.com/summer-bushfires-how-are-the-plant-and-animal-survivors-6-months-on-we-mapped-their-recovery-142551">Summer bushfires: how are the plant and animal survivors 6 months on? We mapped their recovery</a>
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<p>For the many threatened species on Kangaroo Island, such as the critically endangered Kangaroo Island dunnart, their fight for survival still isn’t over. <a href="https://www.publish.csiro.au/WR/WR19137">High numbers of feral cats</a> roaming the landscape now pose a huge threat to their persistence, with little vegetation left within the fire scar to provide cover for wildlife. </p>
<p>In fact, our recent research found there are, on average, almost <a href="https://www.publish.csiro.au/WR/WR19137">double the number of cats</a> per square kilometre on Kangaroo Island than on the mainland.</p>
<h2>The scale of the fires</h2>
<p>Kangaroo Island is uniquely positioned, home to wildlife native to both eastern and western Australia. It protects nationally threatened species, such as the glossy black-cockatoo, the pygmy copperhead, Rosenberg’s goanna and the Kangaroo Island dunnart.</p>
<p>The recent bushfires on Kangaroo Island were the largest ever recorded there, destroying swathes of habitat. Over a period of 49 days the fire burnt 211,255 hectares, impacting almost <a href="https://www.nytimes.com/2020/02/04/world/australia/kangaroo-island-fire.html">half of the island</a>, particularly the western and central regions. </p>
<p>For the critically endangered Kangaroo Island dunnart, the fires burnt <a href="https://theconversation.com/summer-bushfires-how-are-the-plant-and-animal-survivors-6-months-on-we-mapped-their-recovery-142551">approximately 95%</a> of the <a href="https://www.researchgate.net/publication/333446628_The_Kangaroo_Island_dunnart_distribution_status_and_effective_monitoring_methods">species’ known habitat</a> and left them on the brink of extinction.</p>
<h2>Dunnarts face extinction</h2>
<p>The Kangaroo Island dunnart is a small carnivorous marsupial weighing about 20 grams, with soft sooty fur and dark eyes. The species eats mainly insects, and shelters in hollow logs and in the skirts of grass trees. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/ZXwDTe6OWA0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
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<p>Even prior to the fire the species was considered likely to become extinct in the <a href="https://www.publish.csiro.au/PC/pdf/PC18006">next 20 years</a>. Despite extensive survey efforts, the dunnart had only been seen at 19 sites on Kangaroo Island between 1990 and 2019. </p>
<p>Our own survey work between 2017 and 2018 confirmed the persistence of the dunnart at just <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/csp2.4">six sites in the national park</a>, with Kangaroo Island Land for Wildlife detecting several additional records on private land. All sites were in the western half of the island where the recent fires burned. </p>
<p>Many dunnarts are likely to have died in the fire itself, but individuals that survived are left extremely vulnerable to starvation and feral cat predation. </p>
<h2>Cats roaming the island in big numbers</h2>
<p>Between <a href="https://www.sciencedirect.com/science/article/abs/pii/S0006320716309223#:%7E:text=Graphical%20abstract,like%20towns%20and%20intensive%20farms.">two and six million</a> feral cats are estimated to live in Australia, and collectively kill more than <a href="https://www.nespthreatenedspecies.edu.au/1.1.2%20cat%20impacts%20findings%20factsheet_V7.pdf">three billion animals</a> per year.</p>
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Read more:
<a href="https://theconversation.com/dont-let-them-out-15-ways-to-keep-your-indoor-cat-happy-138716">Don't let them out: 15 ways to keep your indoor cat happy</a>
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<p>The problem is so large, a <a href="https://www.aph.gov.au/feralanddomesticcats">parliamentary inquiry</a> is, for the first time in 30 years, investigating the impact of feral and domestic cats to native wildlife.</p>
<p>What’s more, in some areas on Kangaroo Island where the availability of animal carcasses is high, the density of feral cats is more than ten times as high as mainland estimates. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/347030/original/file-20200713-50-r6lm3c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/347030/original/file-20200713-50-r6lm3c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/347030/original/file-20200713-50-r6lm3c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=315&fit=crop&dpr=1 600w, https://images.theconversation.com/files/347030/original/file-20200713-50-r6lm3c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=315&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/347030/original/file-20200713-50-r6lm3c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=315&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/347030/original/file-20200713-50-r6lm3c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=396&fit=crop&dpr=1 754w, https://images.theconversation.com/files/347030/original/file-20200713-50-r6lm3c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=396&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/347030/original/file-20200713-50-r6lm3c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=396&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">There are twice as many cats per square kilometre on Kangaroo Island than on mainland Australia.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<p>A high cat density poses a formidable threat to wildlife survival during the post-fire period, because cats will sometimes travel large distances to <a href="https://www.nature.com/articles/srep22559">hunt within recent fire scars</a>. Research is underway on the island to examine exactly how the fires have changed cat densities and hunting behaviour in and around burnt areas.</p>
<h2>How to control feral cats</h2>
<p>Controlling feral cats is one of the biggest challenges in Australian conservation. Cats are cryptic and cautious, hard to find, see, trap and remove. </p>
<p>Despite the challenge, a large-scale feral cat eradication is underway on Kangaroo Island. This is the largest island on which cat eradication has ever been attempted, and the project will take years.</p>
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Read more:
<a href="https://theconversation.com/one-cat-one-year-110-native-animals-lock-up-your-pet-its-a-killing-machine-138412">One cat, one year, 110 native animals: lock up your pet, it's a killing machine</a>
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<p>In the meantime, feral cats are being controlled around the last refuges for Kangaroo Island dunnarts. There are multiple methods for this including shooting and cage trapping, but in remote areas that are hard to access, poison-baiting is likely to be an effective, long-term strategy.</p>
<p>Most feral cat baits are meat-based, but our research shows possums and bush rats are still <a href="https://www.publish.csiro.au/WR/WR19056">likely to consume them</a>. </p>
<p>Therefore, researchers have worked for many years on strategies to minimise the potential impacts of feral cat baits on native wildlife. For example, the poison can be delivered within a hard plastic pellet, inside the meat bait. </p>
<p>Field trials have indicated that while cats swallow portions of this bait whole, ingesting the pellet, most native wildlife will chew around and <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0107788">discard the pellet</a>. </p>
<h2>Hope emerges after huge survey effort</h2>
<p>Despite the gravity of the risk to Kangaroo Island wildlife, there is hope. A huge, dedicated and effective survey effort by both government and non-government organisations has resulted in the detection of Kangaroo Island dunnarts at more than 22 sites. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/347023/original/file-20200713-50-3bq0bf.jpg?ixlib=rb-1.1.0&rect=8%2C10%2C1446%2C946&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/347023/original/file-20200713-50-3bq0bf.jpg?ixlib=rb-1.1.0&rect=8%2C10%2C1446%2C946&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/347023/original/file-20200713-50-3bq0bf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=395&fit=crop&dpr=1 600w, https://images.theconversation.com/files/347023/original/file-20200713-50-3bq0bf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=395&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/347023/original/file-20200713-50-3bq0bf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=395&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/347023/original/file-20200713-50-3bq0bf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=497&fit=crop&dpr=1 754w, https://images.theconversation.com/files/347023/original/file-20200713-50-3bq0bf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=497&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/347023/original/file-20200713-50-3bq0bf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=497&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Kangaroo Island dunnarts have been spotted in devastated parts of the landscape.</span>
<span class="attribution"><span class="source">Jody Gates</span>, <span class="license">Author provided</span></span>
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</figure>
<p>These small populations have been found mostly within patches of unburnt vegetation, but also – almost unbelievably – in areas that have been completely burnt. </p>
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<strong>
Read more:
<a href="https://theconversation.com/jewel-of-nature-scientists-fight-to-save-a-glittering-green-bee-after-the-summer-fires-139555">'Jewel of nature': scientists fight to save a glittering green bee after the summer fires</a>
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<p>Many of these populations appear to be very small and isolated. And now, more than ever, they’re extremely vulnerable. Targeted cat control and/or protection of vulnerable populations with exclusion fencing may be the only way to prevent their extinction. </p>
<p>By controlling cats, we can help native species like the Kangaroo Island dunnart get through this difficult time, and continue to fulfil their place in that wild landscape for years to come.</p>
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<p><em>The authors would like to acknowledge and thank Paul Jennings, Pat Hodgens, Heidi Groffen, James Smith and Trish Mooney, for their generous contributions to this article.</em></p><img src="https://counter.theconversation.com/content/141201/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rosemary Hohnen counsults for the South Australian Department of Environment and Water. She receives funding from the National Environmental Science Program's Threatened Species Recovery Fund. </span></em></p><p class="fine-print"><em><span>Sarah Legge receives funding from the National Environmental Science Program's Threatened Species Recovery Fund. She is on the Commonwealth Government's Wildlife and Threatened Species Bushfire Recovery Expert Panel, and also on its National Feral Cat Taskforce.</span></em></p>The Kangaroo Island dunnart was listed as critically endangered before fires ripped through 95% of its habitat. Those that survived the fires now face the threat of feral cats.Rosemary Hohnen, Adjunct associate, Charles Darwin UniversitySarah Legge, Professor, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1136412019-03-17T18:48:31Z2019-03-17T18:48:31Z‘Give us a sniff, love’: giving marsupials scents from suitors helps breeding programs<figure><img src="https://images.theconversation.com/files/264062/original/file-20190315-28499-dyfjo3.png?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A baby eastern barred bandicoot pokes its head out of its mother’s pouch. </span> <span class="attribution"><span class="source">M. Parrott, Zoos Victoria</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Smell is a vital part of sexual attraction for all kinds of animals (including humans). We may be able to use smell to improve breeding programs by giving the female animal a sample sniff of potential mates and letting her choose the best one before introducing them.</p>
<p>Our <a href="https://www.sciencedirect.com/science/article/abs/pii/S0168159118305781">new research</a> found female marsupials paired with the male of their choice in captive breeding programs had a higher chance of becoming pregnant, a shorter time to pregnancy and may produce healthier young. </p>
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Read more:
<a href="https://theconversation.com/curious-kids-how-do-we-smell-104772">Curious Kids: How do we smell?</a>
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<h2>Ladies’ choice</h2>
<p>Zoos and breeding institutions traditionally pair animals based on their relatedness and pedigree so they can manage the overall genetic health of the population. It’s expensive and often not possible to transport multiple males just to give a female some options – but if she refuses her solitary suitor when he arrives, it can cause major problems.</p>
<p>Our research shows that presenting the female with a range of scent samples and letting her pick her favourite dramatically increased compatibility. </p>
<p>This simple 10-minute test more than <a href="https://www.sciencedirect.com/science/article/abs/pii/S0168159118305781?via%3Dihub">doubled the number of pregnancies</a> and shortened the time to becoming pregnant in a small carnivorous marsupial, the stripe-faced dunnart. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/264063/original/file-20190315-28502-yvjpg7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/264063/original/file-20190315-28502-yvjpg7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/264063/original/file-20190315-28502-yvjpg7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/264063/original/file-20190315-28502-yvjpg7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/264063/original/file-20190315-28502-yvjpg7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/264063/original/file-20190315-28502-yvjpg7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/264063/original/file-20190315-28502-yvjpg7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/264063/original/file-20190315-28502-yvjpg7.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>
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<span class="caption">Marissa Parrott with a captive-bred mountain pygmy-possum released to the wild.</span>
<span class="attribution"><span class="license">Author provided</span></span>
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<p>Using the same technique in the critically endangered <a href="https://www.zoo.org.au/healesville/animals/mountain-pygmy-possum">mountain pygmy-possum</a> at Healesville Sanctuary, we showed that females had significantly higher breeding success with males they liked during their choice tests. We have shown a similar effect of <a href="http://www.mun.ca/serg/bandicoot-choice.pdf">increasing breeding success and shortening the time to pregnancy</a> in the endangered <a href="https://www.zoo.org.au/werribee/animals/eastern-barred-bandicoot">eastern barred bandicoot</a> at Zoos Victoria through scent and interactions.</p>
<h2>How are female marsupials choosing mates?</h2>
<p>Put simply, they are following their noses. We gave females a choice of male smell and allowed her to sniff out the best mate.</p>
<p>In the first published study of marsupial mate choice, we found female agile antechinus <a href="https://link.springer.com/article/10.1007/s00265-006-0340-8">chose the most genetically suitable male</a> based on his smell. Females preferred males that were genetically dissimilar to themselves (avoiding in-breeding), but not too dissimilar (avoiding genetic out-breeding).</p>
<p>There is a sweet spot to female choice. If you can provide a female with a suite of males, they can choose their most compatible suitor, which in turn is likely to produce the healthiest and fittest young. </p>
<p>Better yet, females are choosing males compared with their own genes, so each female may like a different male, which is good for managing the overall population. However, care must be taken with sisters, as they are likely to have <a href="https://www.sciencedirect.com/science/article/abs/pii/S0168159118305781?via%3Dihub">the same choices</a>.</p>
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<p>
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<strong>
Read more:
<a href="https://theconversation.com/swingers-hookup-program-can-find-the-right-match-for-endangered-species-68579">Swingers' hookup program can find the right match for endangered species</a>
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<p>This information is particularly helpful for global programs that have endangered species spread across different institutions and zoos, such as <a href="https://www.zoo.org.au/healesville/news/rare-tree-kangaroo-joey-emerges-from-pouch-in-healesville-sanctuary-first">tree kangaroos</a>. </p>
<p>In the dunnarts, we found that freezing and storing the scents of males for up to 40 days <a href="https://www.sciencedirect.com/science/article/abs/pii/S0168159118305781?via%3Dihub">did not affect a female’s choice</a> or interest in a scent. Thus, if you have a female tree kangaroo at Melbourne Zoo and are uncertain which male should be sent from overseas, you could freeze scents from eligible bachelors and send them to her in advance for her approval. This could reduce the stress, time and cost associated with sending males between zoos, especially if the male you sent ended up being the wrong choice!</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/264064/original/file-20190315-28505-1w282ev.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/264064/original/file-20190315-28505-1w282ev.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/264064/original/file-20190315-28505-1w282ev.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/264064/original/file-20190315-28505-1w282ev.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/264064/original/file-20190315-28505-1w282ev.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/264064/original/file-20190315-28505-1w282ev.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/264064/original/file-20190315-28505-1w282ev.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/264064/original/file-20190315-28505-1w282ev.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A stripe-faced dunnart in the captive breeding colony at the University of Melbourne.</span>
<span class="attribution"><span class="source">M Parrott</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>But why focus on females?</h2>
<p>In marsupials, females provide the majority of the care of the young. In the extreme case of the antechinus, all males die after mating, leaving the females with all the work <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0122381">raising the offspring</a>. Thus, females are generally the choosier sex, ensuring they get the maximum benefit from appropriate mate choice.</p>
<p>In other species, such as the critically endangered <a href="https://www.zoo.org.au/werribee/news/plains-wanderer-chicks-born">plains wanderer</a> whose females lay eggs and leave them with stay-at-home fathers, you may expect the male bird’s choice to be more important. He is providing the care to the growing chicks and thus will want to maximise their success through choosing the best mate.</p>
<h2>Can people learn from the marsupial approach?</h2>
<p>Female mate choice is a perennial issue for many humans. A <a href="http://www.coherer.org/pub/mhc.pdf">study that supplied 49 women</a> with T-shirts worn by different men found the women could sniff out the men in their genetic “sweet spot” – not too similar or dissimilar – and found those scents most attractive.</p>
<p>We are not so different to the endangered marsupials we are working to recover. Perhaps in the future, instead of swiping right on an image, we can be sent a palette of smells to choose a potential suitor. Instead of speed dating, could we use smell dating? </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/tasmanian-devils-reared-in-captivity-show-they-can-thrive-in-the-wild-68058">Tasmanian devils reared in captivity show they can thrive in the wild</a>
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<p>Certainly, when used in conservation breeding programs, allowing a female to choose her own mate can help find the best pairings, reduce the time to produce young and hopefully help produce the healthiest offspring to fight extinction for their species.</p><img src="https://counter.theconversation.com/content/113641/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Marissa Parrott received funding from The Australian Academy of Science and Winifred Violet Scott Charitable Trust for her work with the stripe-faced dunnart. She works for Zoos Victoria, a not-for-profit zoo-based conservation organisation. Zoos Victoria raises funds to aid their work fighting extinction for endangered species, with a commitment that no Victorian terrestrial vertebrate species will ever go extinct on their watch.</span></em></p>Giving female marsupials a sniff of prospective partners increases the chance of a successful love connection.Marissa Parrott, Reproductive Biologist, Wildlife Conservation & Science, Zoos Victoria, and Honorary Research Associate, BioSciences, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.