tag:theconversation.com,2011:/global/topics/tasmanian-devil-1594/articlesTasmanian Devil – The Conversation2023-03-19T19:04:57Ztag:theconversation.com,2011:article/2018652023-03-19T19:04:57Z2023-03-19T19:04:57ZExtinct but not gone – the thylacine continues to fascinate us<p>Human life on Earth is utterly dependent on biodiversity but our activities are driving an increase in extinctions. Yet some extinct species continue to hold our fascination. <a href="https://theconversation.com/weve-decoded-the-numbat-genome-and-it-could-bring-the-thylacines-resurrection-a-step-closer-176528">New methods in genetics and reproductive biology</a> hold the promise that de-extinction – resurrecting extinct species – <a href="https://www.publish.csiro.au/book/8047/#details">could soon be possible</a>. </p>
<p>But bringing back extinct species is costly. Shouldn’t our focus be on preventing further extinctions? </p>
<p>Almost 20 years ago, for instance, it was looking like impending doom for the Tasmanian devil. It’s the world’s largest surviving marsupial carnivore after the loss of the thylacine. In the words of Oscar Wilde, “<a href="https://doi.org/10.1371/journal.pbio.0040342">to lose both looks like carelessness</a>”. </p>
<p>The enigmatic thylacine, also known as the Tasmanian tiger, continues to capture people’s attention. The size of a wolf, it was officially declared extinct in its last stronghold in Tasmania. Lost before it was ever appreciated or studied, the thylacine is known only from anecdotes. </p>
<p>An iconic symbol of extinction for many but also a symbol of hope, the thylacine has high cultural significance. This iconic animal might still be here if the European colonisers of Tasmania had appreciated a few decades earlier just how unique the thylacine was, as the last member of the marsupial carnivore family Thylacinidae, and stopped persecuting it. </p>
<p>A new book, <a href="https://www.publish.csiro.au/book/8047/#details">Thylacine: The History, Ecology and Loss of the Tasmanian Tiger</a>, presents new evidence-based knowledge about the thylacine in <a href="https://www.publish.csiro.au/samples/TOC_Thylacine.pdf">78 contributions</a> (I wrote the introduction). New scientific and historical methods and large databases mean we can learn much about the ecology and history of this animal from remains it left behind – bones, DNA in skin and bones, rock art, oral histories and historical records. </p>
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Read more:
<a href="https://theconversation.com/can-we-resurrect-the-thylacine-maybe-but-it-wont-help-the-global-extinction-crisis-178425">Can we resurrect the thylacine? Maybe, but it won't help the global extinction crisis</a>
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<h2>We can learn from extinctions to prevent more</h2>
<p>To stem the rate of extinctions we need to better understand the processes of extinction and the species we have lost. To restore species and ecosystems, we need to know the context of how loss of species and their ecological functions has already changed the natural world. </p>
<p>Preventing further extinctions and recovering threatened species need to be the priority. Even common species can slip away rapidly before we notice. </p>
<p>The Tasmanian devil was widespread and abundant before a unique <a href="https://www.science.org/doi/10.1126/science.abb9772">transmissible cancer emerged</a>, cause unknown. Within 30 years of its appearance in the mid-1990s, it spread across the devil’s island range. The population was <a href="https://doi.org/10.1111/ele.13703">reduced by 80%</a>. </p>
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<a href="https://images.theconversation.com/files/515950/original/file-20230316-28-5vnne5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Old black and white photo of man sitting next to a dead thylacine strung up by its hind legs" src="https://images.theconversation.com/files/515950/original/file-20230316-28-5vnne5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/515950/original/file-20230316-28-5vnne5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=738&fit=crop&dpr=1 600w, https://images.theconversation.com/files/515950/original/file-20230316-28-5vnne5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=738&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/515950/original/file-20230316-28-5vnne5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=738&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/515950/original/file-20230316-28-5vnne5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=928&fit=crop&dpr=1 754w, https://images.theconversation.com/files/515950/original/file-20230316-28-5vnne5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=928&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/515950/original/file-20230316-28-5vnne5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=928&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">European colonists’ hunting of the thylacine was not the sole cause of its extinction.</span>
<span class="attribution"><span class="source">AAP/Supplied image</span></span>
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<p>The final demise of the thylacine in the early 1900s appeared rapid and is not easily explained by persecution for <a href="https://www.amazon.com/Tasmanian-tiger-lesson-be-learnt/dp/0958579105">alleged sheep killing</a> or <a href="https://doi.org/10.1016/S0169-5347(00)89050-3">disease</a>.</p>
<p>Many of us still hold out hope the thylacine will be found again. We rarely know the exact date and time of a species extinction. And more than half of Tasmania is remote and unchanged – rugged country that would have supported low numbers of thylacines. </p>
<p>The thylacine’s former strongholds in productive parts of Tasmania are now farmed and humans have dramatically altered the landscape in other ways. People still <a href="https://www.biorxiv.org/content/10.1101/2021.01.18.427214v2">report seeing thylacines</a>, but sightings are subject to psychological biases. In other words, we need a verifiable record of an actual live thylacine to confirm its existence. </p>
<p>Still, despite the compounding odds against its rediscovery, the thylacine offers hope.</p>
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Read more:
<a href="https://theconversation.com/tasmanian-tigers-were-going-extinct-before-we-pushed-them-over-the-edge-88947">Tasmanian tigers were going extinct before we pushed them over the edge</a>
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<h2>To restore ecosystems, we need to understand what’s lost</h2>
<p>To conserve species and restore ecosystems effectively we have to understand historical context. </p>
<p>The thylacine was an apex predator, at the top of the food chain, albeit one that hunted smaller prey relative to its size. This meant it competed for prey with smaller carnivores. Thylacines may have shaped the behaviour and reduced the abundance of devils and quolls and their prey, wallabies and pademelons. This competition thus affected how the devil and quolls <a href="https://doi.org/10.1890/0012-9658(1997)078%5B2569:CDIADC%5D2.0.CO;2">evolved</a> in terms of prey size and the size of their canine teeth. </p>
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<img alt="A Tasmanian devil with its jaws wide open, snarling" src="https://images.theconversation.com/files/515991/original/file-20230317-2270-h1n8e9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/515991/original/file-20230317-2270-h1n8e9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/515991/original/file-20230317-2270-h1n8e9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/515991/original/file-20230317-2270-h1n8e9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/515991/original/file-20230317-2270-h1n8e9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/515991/original/file-20230317-2270-h1n8e9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/515991/original/file-20230317-2270-h1n8e9.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">
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<span class="caption">The Tasmanian devil evolved alongside the thylacine and for a while looked like following it into extinction.</span>
<span class="attribution"><span class="license">Author provided</span></span>
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<p>Wedge-tailed eagles are probably the <a href="https://www.publish.csiro.au/book/8047/#details">closest analogue now to the thylacine</a>. </p>
<p>Losing one species can have cascading effects on the loss of others. The significance of the co-extinction of the <a href="https://www.publish.csiro.au/book/8047/#details">single known host-specific parasite</a> of the thylacine is unknown. However, the important role of parasites in ecosystems is generally under-appreciated.</p>
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Read more:
<a href="https://theconversation.com/the-tasmanian-tiger-was-hunted-to-extinction-as-a-large-predator-but-it-was-only-half-as-heavy-as-we-thought-144599">The Tasmanian tiger was hunted to extinction as a 'large predator' – but it was only half as heavy as we thought</a>
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<h2>The thylacine lives on in culture</h2>
<p>Thylacines were part of the <a href="https://www.publish.csiro.au/book/8047/#details">place-based cosmologies of Aboriginal peoples</a>. Aboriginal peoples hold long <a href="https://www.publish.csiro.au/book/8047/#details">intergenerational knowledge of thylacines</a>, even 3,000 years after their extinction on mainland Australia. </p>
<p>In some places, this knowledge is associated with rock art depictions, which may be regarded as being made by ancestral beings. Oral or written <a href="https://www.publish.csiro.au/book/8047/#details">stories are important</a> in maintaining a connection to the animal and for <a href="https://www.publish.csiro.au/book/8047/#details">reimagining the future</a>. They nourish the hope of seeing the animal again and imagining a connection to its legacy. </p>
<p>In Tasmania, there are constant reminders of the thylacine, which features on logos and the Tasmanian coat of arms.</p>
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Read more:
<a href="https://theconversation.com/should-we-bring-back-the-thylacine-we-asked-5-experts-188894">Should we bring back the thylacine? We asked 5 experts</a>
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<h2>We still dare to hope for its return</h2>
<p>The thylacine might be gone but, in our enthusiasm for seeking knowledge of its ecology, there is still hope it will turn up once again. </p>
<p>The thylacine played an important role in Tasmanian ecosystems and on the Australian mainland. Understanding this role and the factors leading to its extinction provides important context for saving other species and for restoring ecosystems.</p><img src="https://counter.theconversation.com/content/201865/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Menna Elizabeth Jones wrote the introduction to the book discussed in the article, Thylacine: The History, Ecology and Loss of the Tasmanian Tiger.</span></em></p>Australia still feels the thylacine’s presence in its landscape, wildlife and culture. A new book explores everything we know about the thylacine and the hope of a return.Menna Elizabeth Jones, Associate Professor in Zoology, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2014682023-03-15T03:22:02Z2023-03-15T03:22:02ZTasmanian devil whiskers hold the key to protecting these super-scavengers<p>Despite the damage humans cause to the planet, in some cases wildlife can benefit from the presence of people. The Tasmanian devil, for example, frequently feeds on roadkill left by humans.</p>
<p>But our <a href="https://www.nature.com/articles/s41598-023-30490-6">new research</a> suggests this apparent benefit can come at a cost.</p>
<p>We compared the diets of Tasmanian devil populations living in three types of habitat, by examining their whiskers. We found in many cases, Tasmanian devils may be mostly eating foods inadvertently provided by humans. Accessing this food changed the behaviours of Tasmanian devils – and potentially put them in harm’s way. </p>
<p>Our findings are especially important given the risks to Tasmanian devils posed by an aggressive facial tumour disease. If we’re to protect this endangered species, we must conserve environments untouched by humans.</p>
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<img alt="a woman releases a Tasmanian devil from a bag" src="https://images.theconversation.com/files/514848/original/file-20230313-22-lo0j4y.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514848/original/file-20230313-22-lo0j4y.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514848/original/file-20230313-22-lo0j4y.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514848/original/file-20230313-22-lo0j4y.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514848/original/file-20230313-22-lo0j4y.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514848/original/file-20230313-22-lo0j4y.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514848/original/file-20230313-22-lo0j4y.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">
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<span class="caption">The author releases a Tasmanian devil into the wild after sampling for diet analysis.</span>
<span class="attribution"><span class="source">Ariana Ananda</span>, <span class="license">Author provided</span></span>
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<h2>What are Tasmanian devils eating?</h2>
<p>The Tasmanian devil is the biggest carnivorous marsupial in the world. It used to be found on mainland Australia but now wild populations are only found in Tasmania. </p>
<p>Tasmanian devils <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0230216">rarely hunt prey</a>. But they’re highly effective scavengers, thanks to their sharp sense of smell, bone-crushing jaws and energy-efficient movement.</p>
<p>Animals that scavenge for food are “opportunistic feeders” – in other words, they eat whatever they happen to find. This usually means scavengers have a varied diet. </p>
<p>But our previous research found Tasmanian devils have remarkably <a href="https://onlinelibrary.wiley.com/doi/10.1002/ece3.8338">restricted diets</a>. To find out why, we examined Tasmanian devil whiskers. A single whisker can provide a window into the animal’s past.</p>
<p>We used a technique called “<a href="https://www.nationalgeographic.com/culture/article/how-bones-record-where-grew-up-ate">stable isotope analysis</a>”, which enabled us to measure nitrogen and carbon incorporated into the devil’s whiskers as it grows. We matched the chemical composition of the whiskers with potential food items, to determine what the devil ate weeks or months ago. Then we looked at how this varied between individuals living in different habitats.</p>
<p>The technique has been used to describe the diets of <a href="https://theconversation.com/neanderthals-how-a-carnivore-diet-may-have-led-to-their-demise-193764">early humans</a> and <a href="https://theconversation.com/extinct-elephant-birds-were-3-metres-tall-and-weighed-700kg-now-dna-from-fossil-eggshells-reveals-how-they-lived-200628">extinct species</a>. It’s also been used to study the migration patterns of wide-ranging <a href="https://theconversation.com/sights-are-set-on-understanding-bird-movements-across-africa-58943">birds</a> and <a href="https://theconversation.com/australias-right-whales-are-recovering-after-whaling-bans-but-there-are-still-worrying-signs-50379">marine mammals</a>.</p>
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Read more:
<a href="https://theconversation.com/if-wildlife-vigilantes-smuggle-tassie-devils-to-the-australian-mainland-the-animals-could-live-in-secret-for-20-years-160274">If wildlife vigilantes smuggle Tassie devils to the Australian mainland, the animals could live in secret for 20 years</a>
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<figure class="align-center ">
<img alt="A whisker is collected from a Tasmanian devil" src="https://images.theconversation.com/files/514841/original/file-20230313-19-991dmh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514841/original/file-20230313-19-991dmh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514841/original/file-20230313-19-991dmh.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514841/original/file-20230313-19-991dmh.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514841/original/file-20230313-19-991dmh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514841/original/file-20230313-19-991dmh.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514841/original/file-20230313-19-991dmh.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">
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<span class="caption">A whisker is collected from a Tasmanian devil for stable isotope analysis, a technique used to analyse diet over time.</span>
<span class="attribution"><span class="source">Caitlin Newton</span>, <span class="license">Author provided</span></span>
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<h2>And the results?</h2>
<p>We found devil populations in highly disturbed landscapes, such as cleared farmland, fed on just one type of food - medium-sized mammals such as the Tasmanian pademelon. </p>
<p>This is perhaps unsurprising. Pademelons are very common in farming areas, and often end up as roadkill. So Tasmanian devils have little reason to scavenge for any other types of food.</p>
<p>We also examined the diets of devils in eucalypt forest which had been logged and regenerated. These animals also had relatively restricted diets. The result suggests these forests may not have had time to develop mature features such as tree hollows to shelter bird life, a process which can take <a href="https://www.sciencedirect.com/science/article/pii/S0378112708002594">up to 140 years</a>. </p>
<p>However, the results were different for devil populations in old-growth rainforest habitats which have never been logged. There, devil diets were diverse. Larger devils tended to eat mammals such as Tasmanian pademelons and brushtail possums, and smaller devils consumed birds such as green rosellas.</p>
<p>These populations may offer insight into what devil foraging behaviour was like before European settlement.</p>
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Read more:
<a href="https://theconversation.com/meet-moss-the-detection-dog-helping-tassie-devils-find-love-142909">Meet Moss, the detection dog helping Tassie devils find love</a>
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<h2>Saving wild landscapes</h2>
<p>You might think reliable access to food inadvertently provided by humans would benefit Tasmanian devils. But in fact, it can come with hidden dangers.</p>
<p>The presence of roadkill poses risks to devils; they can be attracted to roads and become roadkill themselves. In 2021, <a href="https://www.abc.net.au/news/2022-03-03/tasmanian-devils-killed-on-woolnorth-road/100875670">more than 100</a> devils were reportedly killed by motorists on just one stretch of road in north-west Tasmania. </p>
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<img alt="sign warning of the dangers vehicles pose to Tasmanian devils" src="https://images.theconversation.com/files/515360/original/file-20230315-28-c915gj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/515360/original/file-20230315-28-c915gj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/515360/original/file-20230315-28-c915gj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/515360/original/file-20230315-28-c915gj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/515360/original/file-20230315-28-c915gj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/515360/original/file-20230315-28-c915gj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/515360/original/file-20230315-28-c915gj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Tasmanian devils eating roadkill can be killed by vehicles.</span>
<span class="attribution"><span class="source">Barbara Walton/EPA</span></span>
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<p>And if members of the same species are interacting around a smaller number of carcasses – or in the case of roadkill, the largest and most desirable carcasses – this could encourage the spread of devil facial tumour disease. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/514852/original/file-20230313-18-9ml77s.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/514852/original/file-20230313-18-9ml77s.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514852/original/file-20230313-18-9ml77s.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514852/original/file-20230313-18-9ml77s.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514852/original/file-20230313-18-9ml77s.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514852/original/file-20230313-18-9ml77s.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514852/original/file-20230313-18-9ml77s.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">
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<span class="caption">Tasmanian devils are endangered. Pictured, an individual with devil facial tumour disease.</span>
<span class="attribution"><span class="source">Blake Nisbet</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Over the <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ele.13703">past 25 years</a> the disease – an aggressive, transmittable parasitic cancer is – has caused Tasmania’s devil population to fall by 68%. And this year the disease was <a href="https://www.abc.net.au/news/2023-03-02/tasmanian-devil-facial-tumour-found-in-disease-free-population/102040992">detected</a> for the first time in Tasmania’s north-west, from the same population as many devils in our study.</p>
<p>A <a href="https://theconversation.com/thousands-of-tasmanian-devils-are-dying-from-cancer-but-a-new-vaccine-approach-could-help-us-save-them-194536">vaccine</a> distributed by edible baits is being developed. But in the meantime, a more diverse diet could reduce a devil’s risk of transmitting the disease to others, or catching it.</p>
<p>Only in old-growth rainforests did devils have a diverse diet that lived up to their reputation as opportunists. The results suggest conserving these wild landscapes is vital to protecting Tasmanian devils.</p>
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Read more:
<a href="https://theconversation.com/thousands-of-tasmanian-devils-are-dying-from-cancer-but-a-new-vaccine-approach-could-help-us-save-them-194536">Thousands of Tasmanian devils are dying from cancer – but a new vaccine approach could help us save them</a>
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<img src="https://counter.theconversation.com/content/201468/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anna C. Lewis receives funding from The Winifred Violet Scott Charitable Trust and The Carnivore Conservancy. </span></em></p><p class="fine-print"><em><span>Tracey Rogers receives funding from Australian Research Council and The Winifred Violet Scott Charitable Foundation</span></em></p>The diets of Tasmanian devil are narrowing in areas where humans have changed the landscape. This has big implications for conserving the species.Anna C. Lewis, PhD Candidate, UNSW SydneyTracey Rogers, Professor Evolution & Ecology, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1998792023-02-20T02:25:42Z2023-02-20T02:25:42ZFrom the dingo to the Tasmanian devil - why we should be rewilding carnivores<figure><img src="https://images.theconversation.com/files/510763/original/file-20230217-2564-3bvtm9.jpg?ixlib=rb-1.1.0&rect=31%2C15%2C5083%2C3150&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/pack-dingoes-on-fraser-island-1403646581">Dominic Jeanmaire/Shutterstock</a></span></figcaption></figure><p>No matter where you live, <a href="https://theconversation.com/curious-kids-what-is-the-apex-predator-of-the-world-187616">apex predators</a> and large carnivores inspire awe as well as instil fear.</p>
<p>Large predators have been heavily persecuted and removed from areas where they once lived because of <a href="https://theconversation.com/killing-sharks-wolves-and-other-top-predators-wont-solve-conflicts-96626">conflict</a> with livestock graziers.</p>
<p>Beyond their large teeth, sharp claws and iconic status, <a href="https://www.science.org/doi/10.1126/science.1205106">research</a> is finding they are crucially important in ecosystems. So there is considerable interest in <a href="https://royalsocietypublishing.org/doi/10.1098/rsos.172235">returning large carnivores</a> to areas where they once lived, as part of a shift towards <a href="https://theconversation.com/rewilding-four-tips-to-let-nature-thrive-157441">rewilding</a>. </p>
<p>Bringing back carnivores is <a href="https://www.cambridge.org/core/books/rewilding/2D3CFD33718F14F641AEF83FA1DB21AE">not without risk</a>, but it’s a potentially powerful conservation tool. </p>
<p>Rewilding dingoes and Tasmanian devils in Australia could benefit many of our troubled ecosystems, by keeping herbivore numbers down, keeping feral cats and foxes fearful, and triggering a rebound in vegetation and small animal populations.</p>
<h2>Predators vs prey</h2>
<p>Predators can affect their prey’s behaviour. When prey species know a predator is around and perceive risk to their survival, they change how they behave.</p>
<p>The <a href="https://www.sciencedirect.com/science/article/pii/S0169534719300199?via%3Dihub">landscape of fear</a> predators create can make it harder for prey species to survive. </p>
<p>That’s often good for ecosystems. The effect of dingoes in reducing, say, kangaroo and wallaby populations and changing their behaviour, can actually help bring back plants and smaller animals through a “<a href="https://www.nature.com/scitable/knowledge/library/trophic-cascades-across-diverse-plant-ecosystems-80060347/">trophic cascade</a>”. For example, wolves chasing, eating and scaring deer can lead to an increase in the growth of plants, which can benefit other species.</p>
<p>Predators also affect <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1461-0248.2009.01347.x">other predators</a>. If humans poison, shoot, trap and exclude top predators like dingoes, smaller predators can increase in number and get bolder, in a phenomenon called <a href="https://www.nature.com/articles/23028">mesopredator release</a>. In California, when coyotes disappeared due to habitat destruction, populations of smaller predators such as cats grew and songbird numbers fell.</p>
<h2>How is it done?</h2>
<p><a href="https://theconversation.com/we-can-rewild-swathes-of-australia-by-focusing-on-what-makes-it-unique-111749">Rewilding</a> can occur passively, by changing laws to stop the exclusion or killing of large carnivores and making areas more favourable for carnivores to live. When this happens, species often move back by themselves. Encouragingly, this is happening in <a href="https://www.science.org/doi/10.1126/science.1257553">many parts of the world</a>, including a recent sighting of a wolf in Brandenburg, Germany.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1371116490020302851"}"></div></p>
<p>In other cases, rewilding may need a more active approach, such as physically moving animals to an area. The return of wolves to Yellowstone National Park and the <a href="https://www.youtube.com/watch?v=ysa5OBhXz-Q">ecological transformation</a> that followed is a famous example of this, although in recent times the details of this story have been <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ele.13915">questioned</a>.</p>
<p>When does rewilding work best? <a href="https://www.sciencedirect.com/science/article/pii/S0006320723000095?via%3Dihub">Recent research</a> shows wild-born animals fare better than captive-born animals, though the results are far from conclusive. Wild-born animals may have an edge due to their skills in hunting and defending territories <a href="https://www.sciencedirect.com/science/article/abs/pii/S0006320707004417?via%3Dihub">critically important</a> for survival.</p>
<h2>Rewilding in Australia means bringing back dingoes</h2>
<p>Once carnivores are killed or fenced off from an area, the ecosystem changes. Will we restore nature by bringing them back? Potentially – but it’s not guaranteed.
Australia’s controversial canine, <a href="https://cosmosmagazine.com/nature/amoty/dingo-charismatic-controversial-canid/">the dingo</a>, is a perfect example. Aside from humans, dingoes are Australia’s only living land predator over 15 kilograms. </p>
<p>Dingoes have a vital role in <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1469-185X.2011.00203.x">Australian ecosystems</a>, such as keeping populations of <a href="https://www.publish.csiro.au/wr/WR99030">kangaroos and emus</a> under control. They can also take down feral goats. Their natural control of herbivores means plants can bounce back, as well as making room for smaller animals. Their effect on plant life may even affect the height and shape of <a href="https://www.abc.net.au/news/2023-02-09/dingo-fence-map-ecology-farming-predator-sheep-extinction/101711608">sand dunes</a>. </p>
<p>In some parts of Australia, kangaroo populations <a href="https://onlinelibrary.wiley.com/toc/14428903/2021/22/S1">have exploded</a>. Land clearing for pasture favours kangaroos, as do the dams and water troughs for livestock, the killing off of dingoes and the ending of First Nations Peoples’ cultural practices and hunting.</p>
<p>At times, these population booms have led to sudden crashes, with widespread starvation in droughts. Harvesting kangaroos is one response, but this is often controversial and unpopular. Bringing <a href="https://onlinelibrary.wiley.com/doi/10.1111/rec.12186">dingoes back</a> would help reduce kangaroo numbers in a way more palatable to many people.</p>
<p>When present, dingoes also keep a lid on our worst introduced predators, feral cats and <a href="https://www.publish.csiro.au/am/AM21036">foxes</a>, either by eating them or forcing them to alter <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1111/j.1365-2664.2012.02207.x">their behaviour</a>. If cats and foxes have to be more careful, it may benefit their smaller prey.</p>
<figure class="align-center ">
<img alt="A portrait of a dingo looking into the distance" src="https://images.theconversation.com/files/510778/original/file-20230217-26-gpl5tj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/510778/original/file-20230217-26-gpl5tj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/510778/original/file-20230217-26-gpl5tj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/510778/original/file-20230217-26-gpl5tj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/510778/original/file-20230217-26-gpl5tj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/510778/original/file-20230217-26-gpl5tj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/510778/original/file-20230217-26-gpl5tj.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">
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<span class="caption">Dingoes are a controversial carnivore in Australia.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/dingo-on-beach-great-sandy-national-791883502">Pawel Papis/Shutterstock</a></span>
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</figure>
<p>We could rewild dingoes very easily by removing large barriers like the <a href="https://www.abc.net.au/news/2023-02-09/dingo-fence-map-ecology-farming-predator-sheep-extinction/101711608">dingo fence</a>. This, of course, would trigger pushback from livestock graziers worried about attacks on their stock.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/the-dingo-fence-from-space-satellite-images-show-how-these-top-predators-alter-the-desert-155642">The dingo fence from space: satellite images show how these top predators alter the desert</a>
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<p>It doesn’t have to be this way though. We’ve learned a lot about ways to <a href="https://theconversation.com/guardian-dogs-fencing-and-fladry-protect-livestock-from-carnivores-103290">reduce conflict</a> between farmers and predators. It’s now entirely possible for livestock producers and top predators to coexist. Western Australian farmers are already using guardian animals such as <a href="https://www.abc.net.au/news/2022-08-16/maremmas-protecting-pastoral-sheep-outback-wa/101320626">Maremma dogs</a> to protect livestock.</p>
<h2>So should we do it?</h2>
<p>Australia has been slow to support and attempt large carnivore rewilding. But we can learn valuable lessons from the relocation of Tasmanian devils to an offshore haven, Maria Island. </p>
<p>Devils were introduced to safeguard the species against the severe population decline from devil facial tumour disease. These predators were not native to Maria Island, but they’ve flourished. One unexpected side effect was the <a href="https://www.theguardian.com/environment/2021/jun/21/tasmanian-devils-wipe-out-thousands-of-penguins-maria-island-australia">devastating impact</a> on the island’s little penguin population.</p>
<figure class="align-center ">
<img alt="A close up of a Tasmanian devil" src="https://images.theconversation.com/files/510779/original/file-20230217-18-cgja4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/510779/original/file-20230217-18-cgja4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=406&fit=crop&dpr=1 600w, https://images.theconversation.com/files/510779/original/file-20230217-18-cgja4w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=406&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/510779/original/file-20230217-18-cgja4w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=406&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/510779/original/file-20230217-18-cgja4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=511&fit=crop&dpr=1 754w, https://images.theconversation.com/files/510779/original/file-20230217-18-cgja4w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=511&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/510779/original/file-20230217-18-cgja4w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=511&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">An insurance population of Tasmanian devils has been established on Maria Island.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/XMnQnYND9JU">David Clode/unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Rewilding comes with risks. But it also comes with major benefits, which may help our <a href="https://theconversation.com/existential-threat-to-our-survival-see-the-19-australian-ecosystems-already-collapsing-154077">collapsing ecosystems</a> and <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">threatened species</a>. </p>
<p>Time is short. Conservation must take calculated and informed risks to achieve better outcomes. <a href="https://www.science.org/doi/abs/10.1126/science.aav5570">Rewilding</a> attempts are valuable, even when things don’t go entirely as planned. </p>
<p>What else could we do? Discussions over the carefully planned <a href="https://theconversation.com/should-we-move-tasmanian-devils-back-to-the-mainland-16388">reintroduction of Tasmanian devils</a> to mainland Australia continue. If the devils come back to the mainland for the first time in thousands of years, <a href="https://www.sciencedirect.com/science/article/pii/S0006320715300379">they might</a> help to manage herbivore and feral cat populations.</p>
<p>Rewilding is not about recreating the <a href="https://theconversation.com/indigenous-knowledge-and-the-persistence-of-the-wilderness-myth-165164">mythical idea</a> of wilderness. Humans have <a href="https://www.nature.com/articles/s41559-018-0576-5">shaped ecosystems</a> for millennia. </p>
<p>If rewilding and ecological restoration is to succeed, <a href="https://theconversation.com/academia-can-help-humans-and-large-carnivores-coexist-115467">communities and their values</a>, including First Nations groups, must be involved.</p><img src="https://counter.theconversation.com/content/199879/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Euan G. Ritchie is a Councillor within the Biodiversity Council, and a member of the Ecological Society of Australia and the Australian Mammal Society.</span></em></p>Rewilding is risky but we can learn from past attempts to use it as an effective tool for conservationEuan Ritchie, Professor in Wildlife Ecology and Conservation, School of Life & Environmental Sciences, Deakin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1602742021-07-12T20:08:31Z2021-07-12T20:08:31ZIf wildlife vigilantes smuggle Tassie devils to the Australian mainland, the animals could live in secret for 20 years<figure><img src="https://images.theconversation.com/files/410737/original/file-20210712-25-ee3l4.jpg?ixlib=rb-1.1.0&rect=6%2C6%2C4143%2C2762&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>Tasmanian devil populations have been devastated over the past 25 years due to devil <a href="https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.0040342">facial tumour disease</a>, an infectious cancer. But the Tasmanian government <a href="https://www.smh.com.au/environment/conservation/bringing-back-the-devil-20160823-gqz37b.html">does not support</a> relocating uninfected wild devil populations to the Australian mainland.</p>
<p>Wildlife vigilantes have, however, already illegally moved Tasmanian devils off the island — an illegal practice known as “covert rewilding”. They may well might try again.</p>
<p><a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/conl.12787">My recent research</a> has examined this possibility. It found a covert devil population could remain undetected on the Australian mainland for years, by which time it may be too large and widely distributed to be eradicated.</p>
<p>In fact, it’s possible such rewilding has already occurred, and the calls of covert devils may already be echoing across the Australian Alps or Victoria’s Highlands.</p>
<figure class="align-center ">
<img alt="devil with tumour" src="https://images.theconversation.com/files/410739/original/file-20210712-46002-1sn0y45.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/410739/original/file-20210712-46002-1sn0y45.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/410739/original/file-20210712-46002-1sn0y45.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/410739/original/file-20210712-46002-1sn0y45.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/410739/original/file-20210712-46002-1sn0y45.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/410739/original/file-20210712-46002-1sn0y45.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/410739/original/file-20210712-46002-1sn0y45.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">A facial tumour disease is devastating Tasmanian devil populations.</span>
<span class="attribution"><span class="source">Sarah Peck/AAP</span></span>
</figcaption>
</figure>
<h2>What is covert rewilding?</h2>
<p>Rewilding is the movement of a species back to a location it once existed in, either to maintain ecosystem functioning or prevent the extinction of that species. </p>
<p>In most countries, rewilding decisions rest with public servants in regulatory agencies, who are generally <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1468-0475.2010.00505.x">risk-averse</a>. Rewilding proposals are generally denied, for reasons such as the need to protect other vulnerable species or prevent human-wildlife conflicts.</p>
<p>The overwhelming majority of conservationists operate strictly within the law. But in some cases, guerrilla conservationists take matters into their own hands.</p>
<p>Conclusive evidence of covert rewilding is hard to come by, for obvious reasons. But examples exist.</p>
<p>At Devon in the United Kingdom, <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/mam.12113">beavers were discovered in 2007</a> in a river catchment, after an official application to reintroduce the species was resisted by government and farmers. <a href="https://www.nationalgeographic.co.uk/environment-and-conservation/2017/11/beavers-are-mysteriously-back-britain">Multiple sources believed</a> the reappearance was the result of covert rewilding by so-called “beaver bombers”.</p>
<p>Similarly in the early 2000s, conservationists in Belgium <a href="https://www.researchgate.net/publication/260600032_The_unofficial_return_of_the_European_beaver_Castor_fiber_in_Flanders_Belgium">illegally released</a> beavers at two locations, where the animals subsequently formed permanent populations. </p>
<figure class="align-center ">
<img alt="Eurasian beaver" src="https://images.theconversation.com/files/410916/original/file-20210713-26-1c9snls.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/410916/original/file-20210713-26-1c9snls.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/410916/original/file-20210713-26-1c9snls.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/410916/original/file-20210713-26-1c9snls.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/410916/original/file-20210713-26-1c9snls.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/410916/original/file-20210713-26-1c9snls.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/410916/original/file-20210713-26-1c9snls.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">Covert rewilders released beavers to a Devon river.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Guerrilla conservationists have also covertly relocated populations of <a href="https://www.sciencedirect.com/science/article/abs/pii/S0006320705004234">polecats</a> in Scotland and the <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/9781444312034.ch4">Eurasian lynx</a> in Switzerland and France.</p>
<p>And in Australia in 1996, unknown people <a href="https://dpipwe.tas.gov.au/Documents/STDP%20Tasmanian%20Devil%20Translocation%20Maria%20Island%20development%20and%20environmental%20plan.pdf">covertly released</a> Tasmanian devils onto Badger Island in Bass Strait. The devils were brought to the island by ferry and plane, and once there quickly multiplied. Their descendants were later taken back to Tasmania by officials.</p>
<p>Cancer-free devils have been released into wildlife refuges on the mainland under sanctioned programs, but not into the wild. </p>
<p>Tasmanian devils were once found in the wild across mainland Australia. Three devils were found in Victoria between 1912 and 1991, raising the possibility they were taken from Tasmania and deliberately released.</p>
<p>Devils are easy to catch in traps, and can tolerate captivity and transport. The Badger Island population, for example, was trapped from wild populations then taken to the island by ferry and plane. And the Australian mainland contains an abundance of <a href="https://www.sciencedirect.com/science/article/pii/S0006320715300379">suitable devil habitat</a>.</p>
<p>Introducing species to ecosystems — or reintroducing species that once lived there — carries substantial ecological risks. I do not advocate for or against covert rewilding. But the practice is likely to continue, and it’s important to gain a better understanding of it. </p>
<p>In particular, if authorities wish to halt covert rewilding before it gets out of control, it’s important to identify and monitor the most attractive release locations.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/bones-and-all-see-how-the-diets-of-tasmanian-devils-can-wear-down-their-sharp-teeth-to-blunt-nubbins-162422">Bones and all: see how the diets of Tasmanian devils can wear down their sharp teeth to blunt nubbins</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="people release Tasmanian devils" src="https://images.theconversation.com/files/410738/original/file-20210712-38010-dcc517.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/410738/original/file-20210712-38010-dcc517.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/410738/original/file-20210712-38010-dcc517.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/410738/original/file-20210712-38010-dcc517.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/410738/original/file-20210712-38010-dcc517.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=425&fit=crop&dpr=1 754w, https://images.theconversation.com/files/410738/original/file-20210712-38010-dcc517.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=425&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/410738/original/file-20210712-38010-dcc517.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=425&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cancer-free Tasmanian devils have been released into mainland wildlife refuges, but not the wild.</span>
<span class="attribution"><span class="source">Cristian Prieto/WildArk</span></span>
</figcaption>
</figure>
<h2>Spreading across the landscape</h2>
<p>A key goal of a covert rewilding is to establish a population that, by the time it is discovered, is too large to eradicate. </p>
<p>My modelling involved the hypothetical release of 40 devils at a wide range of locations across Victoria and New South Wales. I modelled how the covert population began to grow, how long it would take to be detected, and how governments could and would respond. </p>
<p>I calculated the annual probability of detection based on the density of the road network and the presence of towns, which affects the chance of the animals being spotted <a href="https://dpipwe.tas.gov.au/Documents/Spotlight%20Report%201992.pdf">by motorists</a> or hikers.</p>
<p>According to the model’s forecasts, a well-planned covert rewilding of Tasmanian devils could remain hidden for <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/conl.12787">more than a decade</a>. By the time it was noticed, the population would have increased to more than 3,000.</p>
<p>Three remote locations emerged as best suited to covert rewilding: two in Victoria’s Alpine National Park and one in Wollemi National Park in New South Wales. These areas had the best combination of suitable habitat, rapid spread rates and low detectability.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/410532/original/file-20210709-17-jclwb6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/410532/original/file-20210709-17-jclwb6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/410532/original/file-20210709-17-jclwb6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/410532/original/file-20210709-17-jclwb6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/410532/original/file-20210709-17-jclwb6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/410532/original/file-20210709-17-jclwb6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/410532/original/file-20210709-17-jclwb6.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">Yellow represents ideal covert rewilding sites for Tasmanian devils on the Australian mainland.</span>
<span class="attribution"><span class="source">Author provided</span></span>
</figcaption>
</figure>
<p>For example, following a release in Alpine National Park, the model predicted discovery by humans after 26 years, by which time the devil population would number 2,200 individuals, spread across 2,800 square kilometres. An earlier detection could easily occur, but there was a 95% chance the population would remain undetected for at least six years — reaching 100 individuals spread across 700 square kilometres.</p>
<p>Once two decades pass before discovery, removal would be expensive and challenging (both logistically and politically).</p>
<p>The lengthy detection lags identified in the research have been borne out by real-world precedents involving covert rewilding. That means if devils have been illegally reintroduced to the Australian mainland in the past two decades, we probably wouldn’t even know it. </p>
<figure class="align-center ">
<img alt="two tassie devils playing" src="https://images.theconversation.com/files/410740/original/file-20210712-71001-4djqrm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/410740/original/file-20210712-71001-4djqrm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/410740/original/file-20210712-71001-4djqrm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/410740/original/file-20210712-71001-4djqrm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/410740/original/file-20210712-71001-4djqrm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/410740/original/file-20210712-71001-4djqrm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/410740/original/file-20210712-71001-4djqrm.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">Tasmanian devils may be roaming the mainland undetected.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Playing devil’s advocate</h2>
<p>Additional regulation and enforcement might not dissuade guerrilla conservationists. <a href="https://www.researchgate.net/publication/246477835_Wildlife_across_our_borders_A_review_of_the_illegal_trade_in_Australia">Very few</a> cases involving the illegal movement of wildlife in Australia lead to convictions. And some guerrilla conservationists are <a href="https://www.researchgate.net/publication/281276691_Foxes_in_Tasmania">not deterred</a> by fines.</p>
<p>From a legal perspective, covert rewilding is hard to stop because Australia’s regulatory framework is full of gaps. For example, the federal government considers species regulation to be a problem for the states, while the states consider the regulation of cross-border species relocations to be a federal problem. Rewilding, and particularly covert rewilding, falls between the cracks.</p>
<p>Covert rewildings typically <a href="https://www.smh.com.au/environment/conservation/bringing-back-the-devil-20160823-gqz37b.html">come after</a> official permission is denied. Often, it’s done without sufficient knowledge of the environment, species interactions and local interests.</p>
<p>It’s worth considering, then, if a more permissive attitude to official rewilding is needed. To quote a British beaver <a href="https://www.nationalgeographic.co.uk/environment-and-conservation/2017/11/beavers-are-mysteriously-back-britain">conservationist</a>: “If we don’t do an official reintroduction, it’ll happen anyway”.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-developed-tools-to-study-cancer-in-tasmanian-devils-they-could-help-fight-disease-in-humans-137710">We developed tools to study cancer in Tasmanian devils. They could help fight disease in humans</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/160274/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Bode received funding from the NESP Threatened Species Hub, and from the Australian Research Council. </span></em></p>In the past, wildlife vigilantes have illegally moved Tasmanian devils off the island — an illegal practice known as “covert rewilding”. They may well might try again.Michael Bode, Professor of Mathematics, Queensland University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1624222021-06-16T20:06:22Z2021-06-16T20:06:22ZBones and all: see how the diets of Tasmanian devils can wear down their sharp teeth to blunt nubbins<figure><img src="https://images.theconversation.com/files/406623/original/file-20210616-21-1chgv1.jpg?ixlib=rb-1.1.0&rect=0%2C4%2C1000%2C661&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Zoos Victoria</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Tasmanian devils are expert scavengers, with strong jaws and robust teeth that give them the notorious ability to eat almost all of a carcass — bones and all.
Scientists have even found echidna spikes in their poo.</p>
<p>But regularly crunching through bone comes at a cost: extreme tooth wear. In our <a href="https://onlinelibrary.wiley.com/doi/10.1002/zoo.21632">new study</a>, we analysed the skulls of nearly 300 devils, and show how regularly crunching through bones wears a devil’s teeth down from sharp-edged weapons to blunt nubbins. </p>
<p>Tasmanian devils <a href="https://www.iucnredlist.org/fr/species/40540/10331066">are endangered</a> and their wild <a href="https://www.zoo.org.au/fighting-extinction/local-threatened-species/tasmanian-devil/">population is continuing to decline</a>. A key part of conserving this marsupial is by maintaining healthy and happy devils in captivity. </p>
<p>Understanding how their food affects their teeth can help us see if captive devils have the same types of tooth wear as their wild counterparts, and look for signs of any unusual or harmful wear. </p>
<h2>Is there anything a devil won’t eat?</h2>
<p>Tasmanian devils are the largest marsupial carnivore alive today. As scavengers, they occupy a unique niche in the Australian ecosystem by disposing of dead animal carcasses.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/406080/original/file-20210614-73826-fs5gf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Devil standing over a dead carcass" src="https://images.theconversation.com/files/406080/original/file-20210614-73826-fs5gf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/406080/original/file-20210614-73826-fs5gf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/406080/original/file-20210614-73826-fs5gf5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/406080/original/file-20210614-73826-fs5gf5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/406080/original/file-20210614-73826-fs5gf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/406080/original/file-20210614-73826-fs5gf5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/406080/original/file-20210614-73826-fs5gf5.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">Captive Tasmanian devils are given a variety of foods to replicate what they’d find in the wild. This photo was taken during a carcass feed at Healesville Sanctuary.</span>
<span class="attribution"><span class="source">Zoos Victoria</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Devils are highly opportunistic and can eat many different types of prey. While their favourites are the carcasses of native mammals such as wombats and wallabies, they’ll also eat reptiles, amphibians, birds, fish, and even insects. </p>
<p>We know this because we find hair, feathers, scales, small bones, claws and more in their poo. </p>
<p>Almost nothing is off limits to devils — they’ll even have a go at a <a href="https://www.themercury.com.au/news/tasmania/tasmanian-devils-see-tragedy-as-opportunity/news-story/2c30fe90393ca47d11b8345785e4f688">stranded whale</a> given the chance. Although devils prefer to scavenge, they’re also <a href="https://doi.org/10.1371/journal.pone.0230216">accomplished hunters</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/tassie-devil-facial-tumour-is-a-transmissible-cancer-34312">Tassie devil facial tumour is a transmissible cancer</a>
</strong>
</em>
</p>
<hr>
<p>But due to a transmissible cancer, <a href="https://theconversation.com/tassie-devil-facial-tumour-is-a-transmissible-cancer-34312">devil facial tumour disease</a>, wild numbers of these remarkable marsupials have <a href="https://theconversation.com/tassie-devils-decline-has-left-a-feast-of-carrion-for-feral-cats-106859">plummeted by around 80%</a>.</p>
<p>Right now, 45 Australian zoos and wildlife sanctuaries, plus an island and a fenced peninsula, are collaborating to maintain a <a href="https://www.publish.csiro.au/book/7675/">healthy population of disease-free devils</a>. It’s important for these institutions to provide captive animals with the right kinds of food for their health and to help make their future release back to disease-free wild locations successful. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/406081/original/file-20210614-72954-e1vx0k.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/406081/original/file-20210614-72954-e1vx0k.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/406081/original/file-20210614-72954-e1vx0k.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=239&fit=crop&dpr=1 600w, https://images.theconversation.com/files/406081/original/file-20210614-72954-e1vx0k.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=239&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/406081/original/file-20210614-72954-e1vx0k.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=239&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/406081/original/file-20210614-72954-e1vx0k.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=300&fit=crop&dpr=1 754w, https://images.theconversation.com/files/406081/original/file-20210614-72954-e1vx0k.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=300&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/406081/original/file-20210614-72954-e1vx0k.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=300&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Devils naturally wear their teeth down from sharp points and edges to blunt, almost flat surfaces by regularly eating bones.</span>
<span class="attribution"><span class="source">Tahlia Pollock</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>This is especially crucial for carnivores, who rely on tough foods to help them develop strong jaws.</p>
<h2>Like hyaenas, but stronger</h2>
<p>The types of food an animal eats will wear their teeth down differently. For example, big cats such as lions prefer to eat the softer parts of a carcass, like flesh or organs, and leave the bones behind. </p>
<p>Spotted hyaenas, however, will happily eat the bones. As a result, hyaenas have incredibly high tooth wear <a href="https://doi.org/10.1111/j.1095-8312.2008.01108.x">compared with lions</a>. </p>
<p>This might not hinder the hyaena or devil as much as you might think. Both have very strong jaws that can compensate for the loss of sharp teeth. In fact, devils have the strongest bite force per body weight of <a href="https://doi.org/10.1098/rspb.2004.2986">any living mammal</a>. </p>
<p>In the interactive below, you can check out 3D models of devil skulls to get a better idea of how much their teeth wear down.</p>
<div class="sketchfab-embed-wrapper">
<iframe title="Toothwear in Tasmanian Devils" frameborder="0" allowfullscreen="" mozallowfullscreen="true" webkitallowfullscreen="true" allow="fullscreen; autoplay; vr" xr-spatial-tracking="" execution-while-out-of-viewport="" execution-while-not-rendered="" web-share="" src="https://sketchfab.com/models/40edaddd833d46ccb44ccec0f3319e9c/embed" width="100%" height="400"> </iframe>
<p> <a href="https://sketchfab.com/3d-models/toothwear-in-tasmanian-devils-40edaddd833d46ccb44ccec0f3319e9c?utm_medium=embed&utm_campaign=share-popup&utm_content=40edaddd833d46ccb44ccec0f3319e9c" target="_blank"> Toothwear in Tasmanian Devils </a> by <a href="https://sketchfab.com/arevans?utm_medium=embed&utm_campaign=share-popup&utm_content=40edaddd833d46ccb44ccec0f3319e9c" target="_blank"> Evans EvoMorph Lab </a> on <a href="https://sketchfab.com?utm_medium=embed&utm_campaign=share-popup&utm_content=40edaddd833d46ccb44ccec0f3319e9c" target="_blank">Sketchfab</a></p></div>
<h2>Comparing wild and captive diets</h2>
<p>By comparing the tooth wear of wild and captive devils, we can see if captive animals are encountering enough hard foods in their diets. </p>
<p>In the <a href="https://dpipwe.tas.gov.au/wildlife-management/save-the-tasmanian-devil-program">Save the Tasmanian Devil Program</a> — an initiative of the federal and Tasmanian governments — captive devils are given a variety of small and large foods at different times, replicating what they’d find in the wild. </p>
<p>We found no signs of different or harmful tooth wear in captive devils, and they showed much the same patterns and types of wear as wild devils. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/meet-moss-the-detection-dog-helping-tassie-devils-find-love-142909">Meet Moss, the detection dog helping Tassie devils find love</a>
</strong>
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<hr>
<p>However, we noticed captive devils wore their teeth more slowly than those in the wild. This may be due to eating higher quality food, such as carcasses that were fresh, whole, and yet to be scavenged.</p>
<p>This means captive institutions are doing a good job of providing devils with the right types of food for their teeth and encouraging wild behaviours. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/406082/original/file-20210614-23-1n6xh9g.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/406082/original/file-20210614-23-1n6xh9g.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/406082/original/file-20210614-23-1n6xh9g.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/406082/original/file-20210614-23-1n6xh9g.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/406082/original/file-20210614-23-1n6xh9g.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/406082/original/file-20210614-23-1n6xh9g.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/406082/original/file-20210614-23-1n6xh9g.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/406082/original/file-20210614-23-1n6xh9g.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">Part of the health check for wild devils involves looking at their teeth. This particular devil has nice sharp tips and edges on their canines and molars.</span>
<span class="attribution"><span class="source">Marissa Parrott/Zoos Victoria</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Collecting data about Tassie devils after they’ve been released confirms this. In 2012 and 2013, devils were released onto Maria Island in Tasmania after being born and raised for around a year in captivity. </p>
<p>Encouragingly, these devils kept the behaviours required to scavenge and hunt prey, and had diets <a href="https://www.publish.csiro.au/wr/wr15221">similar to wild devils</a>. </p>
<h2>How you can help save Tasmanian devils</h2>
<p>Our research is one small, but promising, piece in the overall puzzle. While captive research and breeding programs help conserve the Tasmanian devil, there are ways you can help, too. </p>
<p>Because they like to scavenge the carcasses of dead animals, road kill is especially tempting for devils. But being so close to the road is dangerous and road mortality is the <a href="https://www.zoo.org.au/fighting-extinction/local-threatened-species/tasmanian-devil/">second-biggest killer</a> of wild devils. </p>
<p>So take care on the roads to help wildlife, especially if <a href="https://theconversation.com/10-million-animals-are-hit-on-our-roads-each-year-heres-how-you-can-help-them-and-steer-clear-of-them-these-holidays-149733">driving at night</a>. And if you’re in Tasmania and see a devil that’s been hit on the road, log it in the <a href="https://dpipwe.tas.gov.au/wildlife-management/save-the-tasmanian-devil-program/common-devil-issues/roadkill-tas-app">Roadkill TAS app</a>. </p>
<p>This will help identify road kill hotspots and protect this impressive, but endangered, species.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/10-million-animals-are-hit-on-our-roads-each-year-heres-how-you-can-help-them-and-steer-clear-of-them-these-holidays-149733">10 million animals are hit on our roads each year. Here’s how you can help them (and steer clear of them) these holidays</a>
</strong>
</em>
</p>
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<img src="https://counter.theconversation.com/content/162422/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tahlia Pollock receives funding from the Australian Government Research Training Program Scholarship (RTP stipend), the Monash Graduate Excellence Scholarship (MGE). The research was also funded by the Holsworth Wildlife Research Endowment – Equity Trustees Charitable Foundation & the Ecological Society of Australia.</span></em></p><p class="fine-print"><em><span>Alistair Evans receives funding from the Australian Research Council and Monash University, and is an Honorary Research Affiliate with Museums Victoria.</span></em></p><p class="fine-print"><em><span>David Hocking has received funding from the Australian Research Council and Monash University. </span></em></p><p class="fine-print"><em><span>Marissa Parrott works for Zoos Victoria, a not-for-profit zoo-based conservation organisation. She works closely with partners from the Save the Tasmanian Devil Program and Zoo and Aquarium Association for the conservation of the Tasmanian Devil. Marissa receives no additional payment or funding from outside Zoos Victoria for any work related to threatened species.</span></em></p>Tassie devils are notorious scavengers, eating everything from echidnas to stranded whales. Understanding how their teeth wear down can help us feed and protect captive populations.Tahlia Pollock, PhD candidate, Monash UniversityAlistair Evans, Associate Professor, Monash UniversityDavid Hocking, Curator of Vertebrate Zoology and Palaeontology at the Tasmanian Museum and Art Gallery (TMAG) | Adjunct Research Associate at Monash University, Monash UniversityMarissa Parrott, Reproductive Biologist, Wildlife Conservation & Science, Zoos Victoria, and Honorary Research Associate, BioSciences, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1497332020-12-20T21:12:17Z2020-12-20T21:12:17Z10 million animals are hit on our roads each year. Here’s how you can help them (and steer clear of them) these holidays<figure><img src="https://images.theconversation.com/files/372963/original/file-20201204-19-nz3ip5.jpg?ixlib=rb-1.1.0&rect=26%2C1%2C1171%2C795&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">This is Noojee, a joey koala who was rehabilitated in Healesville Sanctuary after being hit by a car. </span> <span class="attribution"><span class="source">Healesville Sanctuary</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Last month I came across a heartbreaking sight: a group of people standing around a young female kangaroo with horrific injuries. She appeared to have been hit by a car and had dragged herself away, only to collapse into our local creek.</p>
<p>A police officer had gently lifted her out to the bank where her injuries became apparent. A shattered leg, broken arm, and bruising indicating massive internal trauma. She was panting – exhausted and in pain. Fortunately, she had no young joeys in her pouch.</p>
<p>I offered my help as a wildlife specialist. This was a tragic, but common scenario. An estimated <a href="https://www.bbcearth.com/blog/?article=australias-road-kill-map">10 million animals</a> are hit on Australian roads every year.</p>
<p>Australia’s road toll is so high it threatens whole species. Road mortality is the second biggest killer of <a href="https://www.zoo.org.au/fighting-extinction/local-threatened-species/tasmanian-devil/">endangered Tasmanian</a> devils with <a href="https://www.huonvalley.tas.gov.au/slow-down-and-save-our-devils/">around 350</a> killed every year, and the biggest cause of death of <a href="https://www.publish.csiro.au/pc/PC060175">adult endangered cassowaries</a> in Queensland.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/372964/original/file-20201204-19-m0spov.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Noojee all grown up at Healesville Sanctuary, now with a crooked face." src="https://images.theconversation.com/files/372964/original/file-20201204-19-m0spov.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/372964/original/file-20201204-19-m0spov.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372964/original/file-20201204-19-m0spov.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372964/original/file-20201204-19-m0spov.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372964/original/file-20201204-19-m0spov.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372964/original/file-20201204-19-m0spov.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372964/original/file-20201204-19-m0spov.jpg?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">Noojee, all grown up at Healesville Sanctuary, whose face healed a little crookedly.</span>
<span class="attribution"><span class="source">Healesville Sanctuary</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The holiday season is upon us and people are now able to travel to see family and friends again. This means the <a href="https://theconversation.com/where-the-wild-things-are-how-nature-might-respond-as-coronavirus-keeps-humans-indoors-134543">unusually-quiet roads</a> during COVID-19 lockdown — which may have lulled wildlife into a false sense of security — are frighteningly busy. So here’s how you can be wildlife-aware this December.</p>
<h2>Who is hurt?</h2>
<p>As Australia’s population expands, wildlife are pushed into smaller areas, with more roads criss-crossing their habitats. The most visible victims of road expansion are larger mammals such as possums, wombats, kangaroos and koalas. However, millions of smaller animals including <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/avj.12417">echidnas</a>, birds, <a href="https://pubmed.ncbi.nlm.nih.gov/26161722/">reptiles</a> and frogs are also injured or killed each year on our roads.</p>
<p>The <a href="https://www.nrma.com.au/avoid-roos-this-winter">vast majority</a> of insurance claims for animal collisions involve kangaroos, with wallabies and wombats the next most frequent. Smaller animals often go unreported or unnoticed.</p>
<p>Humans are also at risk in these collisions. Every year people crash their vehicles hitting, or trying to avoid hitting, animals on the road, with 5% of <a href="https://www.researchgate.net/publication/23643632_Road_crashes_involving_animals_in_Australia">fatal accidents</a> caused by collisions with animals. Of those, <a href="https://www.budgetdirect.com.au/car-insurance/research/kangaroo-car-accident-statistics.html">42% tried to swerve</a> to avoid the animal. Those who do hit wildlife <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/1742-6723.13361">may also suffer serious injuries</a>, with <a href="https://www.researchgate.net/publication/23643632_Road_crashes_involving_animals_in_Australia">motorcyclists </a> particularly at risk.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/372967/original/file-20201204-21-vg4oom.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A dead kangaroo on the side of the road" src="https://images.theconversation.com/files/372967/original/file-20201204-21-vg4oom.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/372967/original/file-20201204-21-vg4oom.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=353&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372967/original/file-20201204-21-vg4oom.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=353&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372967/original/file-20201204-21-vg4oom.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=353&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372967/original/file-20201204-21-vg4oom.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=444&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372967/original/file-20201204-21-vg4oom.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=444&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372967/original/file-20201204-21-vg4oom.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=444&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A familiar sight to many people hitting country roads this holiday season.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Bracing for a new wave of admissions</h2>
<p>There are a number of aspects that increase the wildlife road toll: <a href="https://www.researchgate.net/publication/262987824_Road_upgrade_road_mortality_and_remedial_measures_Impacts_on_a_population_of_eastern_quolls_and_Tasmanian_devils">better road conditions leading to faster driving</a>, <a href="https://www.researchgate.net/publication/262144556_Australian_mammalogy">young animals dispersing</a> for the first time, higher movements <a href="https://www.researchgate.net/publication/233744140_Kangaroo-vehicle_collisions_in_Australia'_s_sheep_rangelands_during_and_following_drought_periods">during drought</a> or <a href="https://theconversation.com/how-you-can-help-not-harm-wild-animals-recovering-from-bushfires-131385">after fire</a> as animals seek food, water or shelter, <a href="https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0206958&type=printable">breeding season</a> movements in spring-summer, and <a href="https://www.aami.com.au/aami-informed/on-the-road/safe-driving/aami-reveals-peak-periods-for-animal-collisions.html">longer periods of darkness over winter</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-you-can-help-not-harm-wild-animals-recovering-from-bushfires-131385">How you can help – not harm – wild animals recovering from bushfires</a>
</strong>
</em>
</p>
<hr>
<p>Some animals may be hit trying to help a fallen friend or juvenile, as I have seen in galahs and ducks. Others may be hit while feeding on carcasses on the road, like wedge-tailed eagles, <a href="https://www.australiangeographic.com.au/topics/wildlife/2019/10/habitat-loss-car-strikes-and-rodenticides-australias-owls-are-under-pressure/">owls</a> and Tasmanian devils.</p>
<p>Now, as the holiday season begins after months of reduced travel, <a href="https://www.zoo.org.au/healesville/habitats/main-track/australian-wildlife-health-centre/">wildlife hospitals</a> are braced for a new wave of admissions.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/372969/original/file-20201204-23-jl68ur.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="View from inside a bus of an echidna crossing the road" src="https://images.theconversation.com/files/372969/original/file-20201204-23-jl68ur.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/372969/original/file-20201204-23-jl68ur.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372969/original/file-20201204-23-jl68ur.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372969/original/file-20201204-23-jl68ur.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372969/original/file-20201204-23-jl68ur.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372969/original/file-20201204-23-jl68ur.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372969/original/file-20201204-23-jl68ur.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">When smaller animals like echidnas are hit, it often goes unreported or unnoticed.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>How do you avoid a crash?</h2>
<p>Be aware that large marsupials such as wombats, wallabies and kangaroos are most active at <a href="https://www.wildlifevictoria.org.au/images/fact-sheets/10%20-%20Safe%20Driving%20Around%20Wildlife.pdf">dawn and dusk</a>. However, many birds, lizards, snakes and echidnas move during the day. At night, others like frogs, possums, quolls and devils start to roam.</p>
<p>Wildlife warning signs are only installed in high danger areas, so always pay attention to them. Try to <a href="https://rac.com.au/car-motoring/info/car-insurance-animal-collisions">limit your travel</a> between sunset and sunrise, especially near forested or high wildlife areas. If you must drive, stay within the safe speed limit and slow down in areas with wildlife.</p>
<p>Use high beam headlights when safe and watch the sides of the road carefully — animals can often be seen ahead before they flee in front of a vehicle. As you approach the animal, return to normal headlights to avoid dazzling them or causing erratic behaviour.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/373779/original/file-20201209-23-pqwoxs.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Tasmanian devil road sign" src="https://images.theconversation.com/files/373779/original/file-20201209-23-pqwoxs.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/373779/original/file-20201209-23-pqwoxs.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/373779/original/file-20201209-23-pqwoxs.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/373779/original/file-20201209-23-pqwoxs.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/373779/original/file-20201209-23-pqwoxs.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/373779/original/file-20201209-23-pqwoxs.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/373779/original/file-20201209-23-pqwoxs.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">Many marsupials are active between dawn and dusk, be sure to drive slowly.</span>
<span class="attribution"><span class="source">Marissa Parrott</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>What to do if you see an injured animal?</h2>
<p>First, always ensure you are safe. Stop in an easily seen location away from traffic, use your hazard lights and if possible wear bright clothing. Remember, injured animals may be frightened and in pain, and some could be dangerous if approached. </p>
<p>In <a href="https://www.wires.org.au/rescue/emergency-advice">emergency cases</a>, where the animal’s injuries are obvious, some can be carefully caught and wrapped in a towel, then placed in a well-ventilated, <a href="https://www.qld.gov.au/environment/plants-animals/wildlife">dark and secure box</a> for quiet transport to wildlife veterinary hospitals for care. The links above give tips on how to handle some wildlife emergency cases where needed. </p>
<p>I always travel with towels, pillow cases and gloves in my car in case I find an animal in need. You can <a href="https://www.abc.net.au/news/2019-06-22/you-have-hit-a-roo-so-what-do-you-do-next/11235596">check animals found by roads</a> for injuries, and <a href="https://www.wildlifevictoria.org.au/images/fact-sheets/Pouch_Checking_Guide_2019.pdf">surviving young in pouches</a>. </p>
<p>But it’s important you <em>do not</em> approach potentially dangerous animals like snakes, monitor lizards (goannas), bats (flying-foxes or microbats), large macropods (kangaroos or wallabies) or raptors (eagles or hawks). Instead, <a href="https://kb.rspca.org.au/knowledge-base/who-should-i-contact-about-injured-wildlife/">call and wait for trained and vaccinated rescuers</a>. Wildlife Victoria, for example, assisted <a href="https://www.wildlifevictoria.org.au/images/Publications/Annual_Reports/Wildlife_Victoria_Annual_Report_2019_-_LR.pdf">6,875 animals hit by vehicles</a> in 2019 alone.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/372974/original/file-20201204-21-19jsdth.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A long-necked turtle peeking over the water" src="https://images.theconversation.com/files/372974/original/file-20201204-21-19jsdth.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/372974/original/file-20201204-21-19jsdth.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372974/original/file-20201204-21-19jsdth.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372974/original/file-20201204-21-19jsdth.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372974/original/file-20201204-21-19jsdth.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372974/original/file-20201204-21-19jsdth.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372974/original/file-20201204-21-19jsdth.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">This is Toby, a common long-necked turtle, who had a fractured shell after being hit by a car. He was treated by vets and released back into the bush.</span>
<span class="attribution"><span class="source">Healesville Sanctuary</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Innovation for conservation</h2>
<p>In Tasmania, where an <a href="https://www.theguardian.com/australia-news/2018/jan/18/tasmania-launches-roadkill-reduction-effort-to-prevent-500000-wildlife-deaths">estimated 500,000</a> animals are hit on roads every year, a <a href="https://dpipwe.tas.gov.au/wildlife-management/save-the-tasmanian-devil-program/common-devil-issues/roadkill-tas-app">Roadkill Tas</a> App is identifying road kill hot spots to assist research and conservation efforts. </p>
<p>In high kill areas, <a href="https://www.publish.csiro.au/am/AM18012">virtual road fences</a> are being trialled. These posts are activated by car headlights at night and produce sound and light to frighten animals away from the road before a vehicle arrives.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/mysterious-poles-make-road-crossing-easier-for-high-flying-mammals-11323">Mysterious poles make road crossing easier for high flying mammals</a>
</strong>
</em>
</p>
<hr>
<p>Other areas use <a href="https://www.researchgate.net/profile/Brendan_Taylor2/publication/49250893_Roads_and_wildlife_Impacts_mitigation_and_implications_for_wildlife_management_in_Australia/links/556145db08ae9963a119fc37/Roads-and-wildlife-Impacts-mitigation-and-implications-for-wildlife-management-in-Australia.pdf">tunnels under the road</a>, or <a href="https://theconversation.com/mysterious-poles-make-road-crossing-easier-for-high-flying-mammals-11323">overpasses</a> to help wildlife cross safely. </p>
<p>If you know of dangerous areas for wildlife, contact your council to see if warning signs or ways to help wildlife can be installed.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/372976/original/file-20201204-21-1hg0div.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cassowaries on a road" src="https://images.theconversation.com/files/372976/original/file-20201204-21-1hg0div.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/372976/original/file-20201204-21-1hg0div.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372976/original/file-20201204-21-1hg0div.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372976/original/file-20201204-21-1hg0div.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372976/original/file-20201204-21-1hg0div.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372976/original/file-20201204-21-1hg0div.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372976/original/file-20201204-21-1hg0div.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">Collisions on the road is the biggest cause of death of adult Cassowaries in Queensland.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>In the case of my poor little injured kangaroo last month, I worked with the police to make the difficult, but only, decision possible with such traumatic and untreatable injuries. As she was put out of her misery, I thought of all the wildlife hit by cars and left to die.</p>
<p>We can all do our part. Slow down, watch for wildlife, and avoid travel between dawn and dusk. Remind friends, family and tourists to watch for our wildlife. If you do hit an animal, or see one on the road, please stop to help and check pouches if safe. A tiny life may be waiting for your help these holidays.</p>
<hr>
<p><em>If you see an injured animal on the road, call <a href="https://www.wildliferescue.net.au/">Wildlife Rescue Australia</a> on 1300 596 457, or see the <a href="https://kb.rspca.org.au/knowledge-base/who-should-i-contact-about-injured-wildlife/">RSPCA injured wildlife site</a> for specific state and territory numbers.</em></p>
<p><em>Find more tips <a href="https://www.zoo.org.au/summer-with-wildlife/">here</a> for helping local wildlife in need this summer from Zoos Victoria.</em></p><img src="https://counter.theconversation.com/content/149733/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Marissa Parrott works for Zoos Victoria, a not-for-profit zoo-based conservation organisation. Zoos Victoria raises funds for their wildlife hospitals and via their Bushfire Emergency Wildlife Fund to assist short and long-term wildlife welfare and recovery.</span></em></p>As the holiday season begins after months of reduced travel, wildlife hospitals are braced for a new wave of admissions.Marissa Parrott, Reproductive Biologist, Wildlife Conservation & Science, Zoos Victoria, and Honorary Research Associate, BioSciences, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1429092020-07-19T19:53:01Z2020-07-19T19:53:01ZMeet Moss, the detection dog helping Tassie devils find love<figure><img src="https://images.theconversation.com/files/348081/original/file-20200717-27-11rlv87.jpg?ixlib=rb-1.1.0&rect=8%2C0%2C1188%2C800&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Zoos Victoria</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Moss bounds happily through the bush showing the usual exuberance of a young labrador. Despite this looking like play, he is on a serious mission to help fight the extinction of some of our most <a href="https://www.zoo.org.au/fighting-extinction/local-threatened-species/tasmanian-devil/">critically endangered species.</a></p>
<p>Moss is a detection dog in training. Unlike other detection dogs, who might sniff out drugs or explosives, he’ll be finding some of Victoria’s smallest, best camouflaged and most elusive animals.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/sit-seek-fly-scientists-train-dogs-to-sniff-out-endangered-insects-116517">Sit! Seek! Fly! Scientists train dogs to sniff out endangered insects</a>
</strong>
</em>
</p>
<hr>
<p>These dogs use their exceptional olfactory senses to locate everything from koalas <a href="https://www.nature.com/articles/srep08349">high in the trees</a>, desert tortoises <a href="https://pubmed.ncbi.nlm.nih.gov/17069383/">burrowed deep under soil</a> and even <a href="https://www.researchgate.net/publication/293181426_Faecal_sampling_using_detection_dogs_to_study_reproduction_and_health_in_North_Atlantic_right_whales_Eubalaena_glacialis">whales</a> — often more effectively than any human team could aspire to.</p>
<p>What makes Moss unique, however, is he’ll not only find endangered species in the wild, but will also be part of a larger team helping endangered species breed in captivity. These dogs will be the first in the world to do this, starting with a ground-breaking trial with Tasmanian devils. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Sx7HyY-VbBE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Moss will eventually help find the tiny, cryptic Baw Baw Frog in the wild.</span></figcaption>
</figure>
<h2>Why Moss needed a job</h2>
<p>Wildlife detection dogs are a very <a href="https://www.sciencedirect.com/science/article/abs/pii/S0168159117301879">rare type of dog</a> — they are highly motivated, engaged and energetic, but also incredibly reliable and safe around the <a href="https://www.zoo.org.au/fighting-extinction/local-threatened-species/baw-baw-frog/#:%7E:text=All%20estimates%20point%20to%20extinction,hunting%20worms%20and%20other%20invertebrates.">smallest of creatures</a>.</p>
<p>And Moss is the first dog to join Zoos Victoria’s <a href="https://www.zoo.org.au/fighting-extinction/fighting-extinction-dog-squad/">Detection Dog squad</a>, a permanent group of highly trained dogs that will live at Healesville Sanctuary.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/is-your-dog-happy-ten-common-misconceptions-about-dog-behaviour-97541">Is your dog happy? Ten common misconceptions about dog behaviour</a>
</strong>
</em>
</p>
<hr>
<p>Moss was adopted at 14 months old, after he somewhat “failed” at being a family pet. He is a hurricane of energy with an intelligent and playful mind. He’s thriving with a job to keep him occupied and new challenges for his busy brain.</p>
<p>One sign he was perfect for this program was his indifference to the free range chickens at his foster home. For obvious reasons, a dog who likes chasing chickens wouldn’t be a good candidate for protecting some of Australia’s rarest feathered treasures.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/KRzcEVRptxE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Moss will also help monitor incredibly well camouflaged plains-wanderers, which are nearly impossible to spot in the day.</span></figcaption>
</figure>
<p>Currently Moss is learning crucial foundational skills, and getting plenty of exposure to different environments. Equally important, he is developing a deep bond and trust with his handlers.</p>
<p>The detection dog-handler bond is crucial not only for his happiness, but also for working success and longevity. Research from 2018 found a strong bond between a handler and their dog dramatically <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6211013/">improved the dog’s detection results and reduced signs of stress</a>. </p>
<h2>The Tasmanian devil’s advocate</h2>
<p>Healesville Sanctuary <a href="https://www.zoo.org.au/fighting-extinction/local-threatened-species/tasmanian-devil/">breeds endangered Tasmanian Devils every year</a> as part of an <a href="https://www.publish.csiro.au/rd/RD18152">insurance program</a> to support conservation and research. This program is crucial to help <a href="https://theconversation.com/tasmanian-devils-reared-in-captivity-show-they-can-thrive-in-the-wild-68058">protect the devil</a> following an estimated 80% decline in the wild due to a horrific transmissible cancer, <a href="https://dpipwe.tas.gov.au/wildlife-management/save-the-tasmanian-devil-program/about-dftd">Devil Facial Tumour Disease</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-developed-tools-to-study-cancer-in-tasmanian-devils-they-could-help-fight-disease-in-humans-137710">We developed tools to study cancer in Tasmanian devils. They could help fight disease in humans</a>
</strong>
</em>
</p>
<hr>
<p>But managing a predator that’s shy, nocturnal and prefers to be left alone can be tricky. </p>
<p>Wildlife, including Tasmanian devils, need a hands-off approach where possible, so they can <a href="https://www.iflscience.com/plants-and-animals/baby-tasmanian-devils-make-friendships-that-last-for-life/">maintain natural behaviours</a> and thrive in their environment. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/348091/original/file-20200717-27-1s8f9k9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/348091/original/file-20200717-27-1s8f9k9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/348091/original/file-20200717-27-1s8f9k9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/348091/original/file-20200717-27-1s8f9k9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/348091/original/file-20200717-27-1s8f9k9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/348091/original/file-20200717-27-1s8f9k9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/348091/original/file-20200717-27-1s8f9k9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/348091/original/file-20200717-27-1s8f9k9.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">Tasmanian devils prefer to be left alone.</span>
<span class="attribution"><span class="source">Healesville Sanctuary</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>In the wild, devils leave scats (faeces) at communal latrine sites and use <a href="https://institute.sandiegozoo.org/science-blog/everyone-poops-can-you-use-scat-tool-conservation-tasmanian-devil">scent for communication</a>. Male devils can tell a female is ready to mate by smelling her scat. And we think dogs could be trained to detect this, too.</p>
<p>We aim to train dogs to detect an odour profile in the collected scat of female devils coming into their receptive (oestrus) periods, so we can introduce females and suitable males to breed at the optimal time. The odour profile will be further verified via laboratory analyses of hormones in the scats. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/koala-detecting-dogs-sniff-out-flaws-in-australias-threatened-species-protection-121118">Koala-detecting dogs sniff out flaws in Australia's threatened species protection</a>
</strong>
</em>
</p>
<hr>
<p>The project will also explore whether dogs can detect pregnancy and lactation in the devils.</p>
<p>Currently, the best way to determine if a female has young is to look in her pouch, but our preference is to remain at a distance during this important time while females settle into being new mums.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/348092/original/file-20200717-29-16ukcqf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/348092/original/file-20200717-29-16ukcqf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/348092/original/file-20200717-29-16ukcqf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/348092/original/file-20200717-29-16ukcqf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/348092/original/file-20200717-29-16ukcqf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/348092/original/file-20200717-29-16ukcqf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/348092/original/file-20200717-29-16ukcqf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/348092/original/file-20200717-29-16ukcqf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Moss with his trainer, Latoya. Moss is a ball of energy and thrives in the challenging environment of conservation detection.</span>
<span class="attribution"><span class="source">Healesville Sanctuary</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>If the dogs are able to smell a scat sample (while never coming into contact with the devil) and identify that a female is lactating with small joeys in her pouch, we can support her – for example, by increasing her food – while keeping a comfortable distance.</p>
<h2>A new partnership in conservation</h2>
<p>The results from this devil breeding research could offer innovative new options for endangered species breeding programs around the world. </p>
<p>Wildlife detection in the field means we can more accurately monitor some of our most critically endangered species, and quickly assess the impact of catastrophic events such as <a href="https://theconversation.com/how-you-can-help-not-harm-wild-animals-recovering-from-bushfires-131385">bushfires</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-how-far-away-can-dogs-smell-and-hear-139959">Curious Kids: How far away can dogs smell and hear?</a>
</strong>
</em>
</p>
<hr>
<p>Detection dogs are the perfect intermediary between people and wildlife — they can sniff out what we can’t and communicate with us as a team. </p>
<p>And over the next few years, the Detection Dog Squad will expand to five full-time canines. They will all be selected based on their personalities rather than specific breeds, so will likely come in all shapes and sizes.</p>
<p>Dogs may yet go from being man’s best friend to the devil’s best friend and beyond, all starting with a happy labrador named Moss.</p>
<hr>
<p><em>This article is co-authored by Naomi Hodgens, Wildlife Detection Dog Officer at Zoos Victoria, and Dr Kim Miller, Life Sciences Manager, Conservation and Research, at Healesville Sanctuary, Zoos Victoria.</em></p><img src="https://counter.theconversation.com/content/142909/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>La Toya Jamieson is employed by Zoos Victoria, a not-for-profit zoo based conservation organisation. She is also the Treasurer for the Australasian Conservation Dog Network. La Toya receives no additional payment outside Zoos Victoria for any work with detection dogs or threatened species. </span></em></p><p class="fine-print"><em><span>Marissa Parrott works for Zoos Victoria, a not-for-profit zoo-based conservation organisation. She works closely with partners from the Save the Tasmanian Devil Program and Zoo and Aquarium Association for the conservation of the Tasmanian Devil. Marissa receives no additional payment or funding from outside Zoos Victoria for any work related to threatened species.</span></em></p>Moss is part of an elite squad of detection dogs that will locate threatened species in the wild and help endangered species breed in captivity.La Toya Jamieson, Wildlife Detection Dog Specialist, La Trobe UniversityMarissa Parrott, Reproductive Biologist, Wildlife Conservation & Science, Zoos Victoria, and Honorary Research Associate, BioSciences, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1377102020-07-01T20:10:26Z2020-07-01T20:10:26ZWe developed tools to study cancer in Tasmanian devils. They could help fight disease in humans<figure><img src="https://images.theconversation.com/files/344963/original/file-20200701-54166-1kw4qbn.jpg?ixlib=rb-1.1.0&rect=5%2C5%2C3455%2C2298&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/tasmanian-devil-688398328">Shutterstock</a></span></figcaption></figure><p>Emerging infectious diseases, including COVID-19, usually come from <a href="https://www.nature.com/articles/nature06536">non-human animals</a>. However our understanding of most animals’ immune systems is sadly lacking as there’s a shortfall in research tools for species other than humans and mice.</p>
<p><a href="https://advances.sciencemag.org/content/6/27/eaba5031">Our research</a> published today in Science Advances details cutting edge immunology tools we developed to understand cancer in Tasmanian devils. Importantly, these tools can be rapidly modified for use on any animal species. </p>
<p>Our work will help future wildlife conservation efforts, as well as preparedness against potential new diseases in humans. </p>
<h2>The fall of the devil</h2>
<p>Tasmanian devil populations have undergone a steep decline in recent decades, due to a lethal cancer called devil facial tumour disease (DFTD) first detected in 1996. </p>
<p>A decade after it was discovered, genetic analysis revealed DFT <a href="https://www.nature.com/articles/439549a">cells are transmitted</a> between devils, usually when they bite each other during mating. A second type of <a href="http://www.pnas.org/lookup/doi/10.1073/pnas.1519691113">transmissible devil facial tumour</a> (DFT2) was detected in 2014, suggesting devils are prone to developing contagious cancers.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/335088/original/file-20200514-77235-1g30855.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/335088/original/file-20200514-77235-1g30855.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=624&fit=crop&dpr=1 600w, https://images.theconversation.com/files/335088/original/file-20200514-77235-1g30855.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=624&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/335088/original/file-20200514-77235-1g30855.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=624&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/335088/original/file-20200514-77235-1g30855.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=784&fit=crop&dpr=1 754w, https://images.theconversation.com/files/335088/original/file-20200514-77235-1g30855.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=784&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/335088/original/file-20200514-77235-1g30855.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=784&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A Tasmanian devil with devil facial tumour disease.</span>
<span class="attribution"><span class="source">Save the Tasmanian Devil Program</span></span>
</figcaption>
</figure>
<p>In 2016, researchers reported some wild devils had <a href="http://rsbl.royalsocietypublishing.org/lookup/doi/10.1098/rsbl.2016.0553">natural immune responses against DFT1 cancers</a>. A year later an experimental vaccine for the original devil facial tumour (DFT1) was tested in devils artificially inoculated with cancer cells. </p>
<p>While the vaccine didn’t protect them, in some cases subsequent treatments were able to <a href="https://www.nature.com/articles/srep43827">induce tumour regression</a>.</p>
<p>But despite the promising results, and other <a href="https://academic.oup.com/gbe/article/10/11/3012/5129084">good news from the field</a>, DFT1 continues to suppress devil populations across most of Tasmania. And DFT2 poses an additional threat. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/deadly-disease-can-hide-from-a-tasmanian-devils-immune-system-70594">Deadly disease can 'hide' from a Tasmanian devil's immune system</a>
</strong>
</em>
</p>
<hr>
<h2>Following a blueprint requires tools</h2>
<p>In humans, there has been <a href="https://www.nobelprize.org/prizes/medicine/2018/press-release/">incredible progress</a> in treatments targeting protein that regulate our immune system. These treatments work by stimulating the immune system to kill cancer cells. </p>
<p>Our team’s analyses of devil DNA showed these <a href="https://www.frontiersin.org/articles/10.3389/fimmu.2017.00513/full">immune genes are also present in devils</a>, meaning we may be able to develop similar treatments to stimulate the devil immune system.</p>
<p>But studying the DNA blueprint for devils takes us only so far. To build a strong house, you need to understand the blueprint <em>and</em> have the right tools. Proteins are the building blocks of life. So to build effective treatments and vaccines for devils we have to study the proteins in their immune system. </p>
<p>Until recently, there were few research tools available for this. And this problem was all too familiar to researchers studying immunology and disease in species other than humans, mice or rats.</p>
<h2>Into the FAST lane</h2>
<p>You could build a house with just a saw, hammer and nails – but a better and faster build requires a larger, more versatile toolbox. </p>
<p>In <a href="https://advances.sciencemag.org/content/6/27/eaba5031">our new research</a>, we’ve added more than a dozen tools to the toolbox for understanding tumours in Tasmanian devils. These are Fluorescent Adaptable Simple Theranostic proteins – or simply, <a href="https://youtu.be/Za6QuZOTR_0">FAST proteins</a>. </p>
<p>The term “theranostic” merges therapeutic and diagnostic. FAST proteins can be used as a therapeutic drug to treat a disease, or as a diagnostic tool to determine its cause and better understand it.</p>
<p>A key feature of FAST proteins is they can be tagged with a fluorescent protein marker, and can be released from the cells that we engineered in the lab to make them. </p>
<p>This way, we can collect and observe how the proteins attach and interact with other proteins without needing to add a tag later in the process. </p>
<p>To understand this, imagine trying to use a tiny key in a tiny lock in the dark. It would be difficult, but much easier if both were tagged with a coloured light. In the context of the immune system, it’s easier to understand what we need to turn on or off if we can see where the proteins are.</p>
<p>By mapping how proteins within the devil’s immune system interact, we can find better ways to stimulate the immune system. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/335089/original/file-20200514-77251-lyndmg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/335089/original/file-20200514-77251-lyndmg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=197&fit=crop&dpr=1 600w, https://images.theconversation.com/files/335089/original/file-20200514-77251-lyndmg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=197&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/335089/original/file-20200514-77251-lyndmg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=197&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/335089/original/file-20200514-77251-lyndmg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=248&fit=crop&dpr=1 754w, https://images.theconversation.com/files/335089/original/file-20200514-77251-lyndmg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=248&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/335089/original/file-20200514-77251-lyndmg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=248&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">An overview of the FAST protein system. Fluorescent proteins and immune system proteins from different species can be rapidly swapped to make new FAST proteins.</span>
<span class="attribution"><span class="source">Andrew S. Flies/WildImmunity</span></span>
</figcaption>
</figure>
<p>The FAST system is also adaptable, meaning new targets can be cut-and-pasted into the system as they’re identified, like changing the bits on a drill. Therefore, it’s useful for studying the immune systems of other animals too, including humans. </p>
<p>Also, the system is simple enough that most people with basic cell culture and molecular biology experience could use it. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-virus-is-attacking-koalas-genes-but-their-dna-is-fighting-back-124896">A virus is attacking koalas' genes. But their DNA is fighting back</a>
</strong>
</em>
</p>
<hr>
<h2>Needle in a haystack</h2>
<p>Cancer cells in humans and animals can travel via the bloodstream to spread, or “metastasise”, throughout the body. Identifying single tumour cells in blood can shed light on how cancer invades devils’ organs and kills them. </p>
<p>Using FAST tools, we discovered CD200 – a protein that inhibits anti-cancer responses in humans – is highly expressed in devils. With FAST tools, we were able to mix DFT2 cancer cells into devil blood and pick them out, despite there being about one cancer cell for every 1,000 blood cells.</p>
<p>CD200 is a powerful “off switch” for the immune system, so identifying this off switch allows us it can help us produce a vaccine that disables the switch.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/335091/original/file-20200514-77235-102618j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/335091/original/file-20200514-77235-102618j.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=449&fit=crop&dpr=1 600w, https://images.theconversation.com/files/335091/original/file-20200514-77235-102618j.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=449&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/335091/original/file-20200514-77235-102618j.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=449&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/335091/original/file-20200514-77235-102618j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=564&fit=crop&dpr=1 754w, https://images.theconversation.com/files/335091/original/file-20200514-77235-102618j.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=564&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/335091/original/file-20200514-77235-102618j.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=564&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A devil facial tumour 2 (DFT2) cell, with the cell nucleus shown in blue.</span>
<span class="attribution"><span class="source">Andrew S. Flies/WildImmunity</span></span>
</figcaption>
</figure>
<p>By rapidly sifting out the best ways to stimulate the devil’s immune system, FAST tools are accelerating our research into developing a <a href="https://www.tandfonline.com/doi/full/10.1080/14760584.2020.1711058">preventative vaccine to protect devils from DFT</a>.</p>
<h2>Why study animal immune systems?</h2>
<p>COVID-19 has once again brought emerging infectious diseases onto the global stage. The ability to rapidly develop immunology tools for new species means we can jump into action when a new virus jumps into humans. </p>
<p>Additionally, species are going extinct at an alarming rate, and wildlife disease is increasingly threatening conservation efforts. </p>
<p>Understanding how the immune systems of other animals fight diseases could provide a blueprint for developing vaccines and therapeutics to help them.</p><img src="https://counter.theconversation.com/content/137710/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew S. Flies receives funding from the University of Tasmania and the Australian Research Council. He has previously received funding from Nexvet Australia as part of an Innovation Connections grant and the Royal Hobart Hospital Research Foundation. He co-founded the not-for-profit organisations Science in the Pub Adelaide and Science in the Pub Tasmania. </span></em></p><p class="fine-print"><em><span>Amanda L. Patchett receives funding from the Save the Tasmanian Devil Appeal via the University of Tasmania. </span></em></p><p class="fine-print"><em><span><a href="mailto:bruce.lyons@utas.edu.au">bruce.lyons@utas.edu.au</a> receives funding from the ARC and from the Save the Tasmanian Devil Appeal via the University of Tasmania.</span></em></p><p class="fine-print"><em><span>Greg Woods 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>The cutting-edge tools could greatly expand our understanding of different species’ immune systems, and also help humans prepare for future disease outbreaks.Andrew S. Flies, Senior Research Fellow in Immunology, University of TasmaniaAmanda L. Patchett, University of TasmaniaBruce Lyons, University of TasmaniaGreg Woods, Professional Research Fellow, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1162712019-05-06T05:09:26Z2019-05-06T05:09:26ZSexual aggression key to spread of deadly tumours in Tasmanian devils<figure><img src="https://images.theconversation.com/files/272146/original/file-20190502-117604-2lcbwp.jpg?ixlib=rb-1.1.0&rect=111%2C298%2C2859%2C1540&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Both male and female Tasmanian devils can become very violent during sexual interactions. </span> <span class="attribution"><span class="source">Shutterstock/PARFENOV</span></span></figcaption></figure><p>Tasmanian devils have a reputation as a fearsome animal – most of the time this is undeserved. When it comes to the mating season, however, it’s a fair judgement. Between February and April, mating can be incredibly aggressive, with male and female devils prone to biting one another both during and after the act.</p>
<p>That could be deadly for the devils, according to <a href="https://academic.oup.com/beheco/advance-article/doi/10.1093/beheco/arz054/5479352" title="Rate of intersexual interactions affects injury likelihood in Tasmanian devil contact networks">new research published online in the journal Behavioral Ecology</a>.</p>
<p>Unfortunately, biting <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1111/j.1365-2656.2012.02025.x" title="Biting injuries and transmission of Tasmanian devil facial tumour disease">drives the spread of devil facial tumour disease</a> (<a href="https://dpipwe.tas.gov.au/wildlife-management/save-the-tasmanian-devil-program/about-dftd">DFTD</a>) a transmissible cancer that has been afflicting the species since the mid-1990s.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/survival-of-the-fittest-perhaps-not-if-youre-a-tasmanian-devil-76402">Survival of the fittest? Perhaps not if you're a Tasmanian devil</a>
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<p>DFTD is highly unusual for a cancer because it can <a href="https://theconversation.com/tassie-devil-facial-tumour-is-a-transmissible-cancer-34312">transfer between individual devils and grow in its new host</a>.</p>
<p>The fact that devils regularly bite one another around the mouth means tumour cells can easily transfer from an infected devil to an open wound on a healthy devil. This makes the buildup of wounds in devils extremely important to our understanding of this disease.</p>
<h2>When devils mate</h2>
<p>In our <a href="https://academic.oup.com/beheco/advance-article/doi/10.1093/beheco/arz054/5479352" title="Rate of intersexual interactions affects injury likelihood in Tasmanian devil contact networks">study</a>, we examined the accumulation of bite wounds in a population of wild devils in northwest Tasmania.</p>
<p>We found males were much more likely than females to pick up high numbers of bite wounds. But these wounds appear to be related to the amount of time males spent in mating season interactions with females, as opposed to fights with other males (as we had previously thought).</p>
<p>In the mating season, after male devils have mated with females, they spend an extended period either confining the female in a den, or closely following her to make sure other males are unable to mate with her. </p>
<p>During our study we found this behaviour could go on for up to two weeks in the wild. The process is known as “<a href="https://www.sciencedirect.com/topics/neuroscience/mate-guarding">mate guarding</a>” and is relatively common in the animal kingdom.</p>
<p>We found the longer males spent engaging in mate guarding behaviour, the more bite wounds they received. This would seem to put successful males, who mate with a high number of females, in the firing line when it comes to acquiring DFTD.</p>
<p>But <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2664.13088" title="Density trends and demographic signals uncover the long‐term impact of transmissible cancer in Tasmanian devils">no pattern of sex bias in DFTD prevalence</a> has ever been observed in the wild.</p>
<p>So how does this fit with our study on the increased vulnerability in males?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/272155/original/file-20190502-103068-ecwq5j.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/272155/original/file-20190502-103068-ecwq5j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/272155/original/file-20190502-103068-ecwq5j.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=388&fit=crop&dpr=1 600w, https://images.theconversation.com/files/272155/original/file-20190502-103068-ecwq5j.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=388&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/272155/original/file-20190502-103068-ecwq5j.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=388&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/272155/original/file-20190502-103068-ecwq5j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=488&fit=crop&dpr=1 754w, https://images.theconversation.com/files/272155/original/file-20190502-103068-ecwq5j.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=488&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/272155/original/file-20190502-103068-ecwq5j.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=488&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 Tasmanian devil with the Devil Facial Tumour Disease.</span>
<span class="attribution"><a class="source" href="https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.0040342">Menna Jones/PLOS ONE</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Disease transfer</h2>
<p>A crucial unknown in the DFTD transmission process involves directionality – which way the deadly disease is passed on by a devil. There are two possibilities:</p>
<ol>
<li><p>an infected devil bites an uninfected animal, transferring tumour cells (from its teeth or saliva) directly into the wound it causes</p></li>
<li><p>an uninfected devil bites into tumours on an infected animal, and cells transfer into an open wound inside the biter’s mouth. </p></li>
</ol>
<p>The reality is likely to involve a combination of the two.</p>
<p>Our results indicate that most disease transmission occurs during extended mating season interactions, when females appear to be causing high numbers of wounds to their mates.</p>
<p>If DFTD can transfer in either direction during these encounters, then both the males receiving the wounds and the females causing them would be equally at risk of acquiring the disease.</p>
<h2>Future of the devil</h2>
<p>We have highlighted mating season encounters between the sexes as crucial transmission points for the spread of DFTD. The behaviour of male devils appears to be driving patterns that support transmission of the disease.</p>
<p>This information is important for potential disease management options, as it pinpoints males in good condition – who are likely to be reproductively successful – as targets for management interventions, such as vaccinations. </p>
<p>Most importantly, these results add one more piece to the puzzle of rapid evolution in the Tasmanian devil, in response to the strong evolutionary pressure DFTD is placing on this iconic species. With almost 100% mortality once devils reach breeding age, any advantage an individual devil might have to survive a little longer and reproduce should – over time – spread through the population. </p>
<p>The species has already shown remarkably rapid shifts in their <a href="https://www.pnas.org/content/105/29/10023.short" title="Life-history change in disease-ravaged Tasmanian devil populations">life history</a> and <a href="https://www.nature.com/articles/ncomms12684" title="Rapid evolutionary response to a transmissible cancer in Tasmanian devils">genome</a>, while some are able to mount an <a href="https://royalsocietypublishing.org/doi/full/10.1098/rsbl.2016.0553">immune response and recover from the tumours</a>.</p>
<p>DFTD is spread through biting so we can expect strong evolutionary pressure for devils to become less aggressive towards each other over time. </p>
<p>With these new results, we can now pinpoint for the first time <em>who</em> (healthy, successful males) and <em>when</em> (guarding females after mating) the intense selection pressure on aggressive behaviour in devils will operate.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/could-tassie-devils-help-control-feral-cats-on-the-mainland-fossils-say-yes-63120">Could Tassie devils help control feral cats on the mainland? Fossils say yes</a>
</strong>
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</p>
<hr>
<p>Ultimately, devils will solve the DFTD problem themselves by evolving resistance, tolerance and changing their behaviour. One of the best things we can do is let evolution take its course, giving a helping hand along the way via well guided management actions.</p><img src="https://counter.theconversation.com/content/116271/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Hamilton receives funding from the Holsworth Wildlife Research Endowment. </span></em></p><p class="fine-print"><em><span>Elissa Cameron receives funding from Australian Research Council, the Holsworth Wildlife Trust, Marsden Fund. </span></em></p><p class="fine-print"><em><span>Menna Elizabeth Jones receives funding from the Australian Research Council, the Ian Potter Foundation, the US National Institute of Health, the US National Science Foundation, the Holsworth Wildlife Trust, the University of Tasmania Foundation Dr Eric Guiler grants. </span></em></p><p class="fine-print"><em><span>Rodrigo Hamede receives funding from Australian Research Council. </span></em></p>Tasmanian Devils can be incredibly aggressive during mating season and their biting can have fatal consequences.David Hamilton, PhD Candidate in Zoology, University of TasmaniaElissa Cameron, Professor of Wildlife Ecology, University of TasmaniaMenna Elizabeth Jones, Associate Professor in Zoology, University of TasmaniaRodrigo Hamede, Post Doctoral Research Fellow, Conservation Biology and Wildlife Management, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/631202019-02-25T19:09:07Z2019-02-25T19:09:07ZCould Tassie devils help control feral cats on the mainland? Fossils say yes<figure><img src="https://images.theconversation.com/files/260354/original/file-20190222-195876-1pvj44l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Tasmanian devil once thrived on mainland Australia.</span> <span class="attribution"><span class="source">Shutterstock/mastersky</span></span></figcaption></figure><p>The <a href="https://australianmuseum.net.au/learn/animals/mammals/tasmanian-devil/">Tasmanian devil</a> – despite its name – once roamed the mainland of Australia. Returning the devil to the mainland may not only help its <a href="https://www.threatenedspecieslink.tas.gov.au/Pages/Tasmanian-Devil.aspx">threatened status</a> but could help control invasive predators such as feral cats and foxes.</p>
<p>The idea of returning devils to the mainland has <a href="https://theconversation.com/should-we-move-tasmanian-devils-back-to-the-mainland-16388">been raised</a> <a href="https://www.smh.com.au/technology/reintroducing-dingoes-can-help-manage-feral-foxes-and-cats-study-suggests-20170523-gwb8e6.html">before</a>.</p>
<hr>
<p>
<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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</em>
</p>
<hr>
<p>But now we’ve explored the idea from a palaeontological view. We looked at the fossil record of mainland devils, in a <a href="https://doi.org/10.1016/j.biocon.2019.02.002" title="A palaeontological perspective on the proposal to reintroduce Tasmanian devils to mainland Australia to suppress invasive predators">paper published online</a> and in print soon in the journal Biological Conservation.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/260294/original/file-20190221-195857-173ckxd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/260294/original/file-20190221-195857-173ckxd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/260294/original/file-20190221-195857-173ckxd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/260294/original/file-20190221-195857-173ckxd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/260294/original/file-20190221-195857-173ckxd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/260294/original/file-20190221-195857-173ckxd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/260294/original/file-20190221-195857-173ckxd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/260294/original/file-20190221-195857-173ckxd.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 well preserved devil mandible (lower jaw) recovered from excavations west of Townsville.</span>
<span class="attribution"><span class="source">Gilbert Price</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The fossil record helps us better understand how the devils co-existed on mainland Australia with other wildlife. It also helps us see how these iconic animals may possibly interact with small and medium-sized animals if reintroduced to the mainland in the future.</p>
<h2>Back in the wild</h2>
<p>Ecologists have reintroduced several apex predators to environments where they were once driven to localised extinction. This has helped restore past ecosystems by providing a clearer ecological balance. </p>
<p>One of the best-known examples is the <a href="https://www.yellowstonepark.com/park/yellowstone-wolves-reintroduction">reintroduction of wolves</a> to Yellowstone National Park in the United States, to check the overgrazing and destruction of habitat by elk.</p>
<p>By reintroducing Tasmanian devils into mainland Australia, can we possibly help restore ecological systems that support devils along with small to medium-sized native mammals? </p>
<h2>Native and exotic predators</h2>
<p>Tasmanian devils and <a href="https://australianmuseum.net.au/learn/australia-over-time/extinct-animals/the-thylacine/">thylacines</a> (Tasmanian tigers) were displaced across the mainland of Australia sometime after the <a href="https://australianmuseum.net.au/learn/animals/mammals/dingo/">dingo was introduced</a> from southeast Asia at least 3,500 years ago.</p>
<p>But these iconic Australian predators were still able to survive in Tasmania. The island was created 10,000 years ago by rising sea levels, well before the arrival of dingoes on mainland Australia.</p>
<p>Dingoes have now been eradicated across much of mainland Australia, particularly within the seclusion zone of the <a href="https://theconversation.com/lets-move-the-worlds-longest-fence-to-settle-the-dingo-debate-37155">dingo fence</a> in the southeast of the continent. The 5,400km fence stretches eastwards across South Australia into New South Wales and to southeast Queensland.</p>
<p>Exotic predators such as foxes and cats now thrive across many parts of Australia, and have <a href="https://theconversation.com/invasive-predators-are-eating-the-worlds-animals-to-extinction-and-the-worst-is-close-to-home-64741">devastating impacts on small to medium-sized Australian mammals</a>. </p>
<p>But until recently they have not been able to gain a foothold in Tasmania. Many ecologists believe the presence of the devil has prevented these other animals making their destructive mark on the ecology of Tasmania. </p>
<p>Sadly the situation is changing as a result of the <a href="https://dpipwe.tas.gov.au/wildlife-management/save-the-tasmanian-devil-program/about-dftd">deadly devil facial tumour disease</a>, an infectious cancer that has destroyed many populations of Tasmanian devils. <a href="http://www.bbc.com/earth/story/20170321-how-the-tasmanian-devil-has-responded-to-infectious-cancers">Estimates range up to 90%</a> of some population groups now wiped out.</p>
<p>As a result, <a href="https://theconversation.com/tassie-devils-decline-has-left-a-feast-of-carrion-for-feral-cats-106859">feral cats are now moving into former devil habitats</a> and hunting native species on Tasmania. </p>
<h2>A fossil window to the past</h2>
<p>So what does the fossil record tell us about the past life of the Tasmanian devil in mainland Australia?</p>
<p>The <a href="http://www.visitmungo.com.au/world-heritage">Willandra Lakes World Heritage Area</a>, in southeast Australia, provides an extraordinary archaeological and palaeoecological record of Ice Age Australia.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/260289/original/file-20190221-195870-1cx8hqs.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/260289/original/file-20190221-195870-1cx8hqs.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/260289/original/file-20190221-195870-1cx8hqs.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/260289/original/file-20190221-195870-1cx8hqs.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/260289/original/file-20190221-195870-1cx8hqs.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/260289/original/file-20190221-195870-1cx8hqs.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/260289/original/file-20190221-195870-1cx8hqs.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/260289/original/file-20190221-195870-1cx8hqs.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">Recovery of fossils and devil coprolites from eroding bettong burrows at the Willandra Lakes World Heritage Area.</span>
<span class="attribution"><span class="source">Michael Westaway</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>In the past, skeletal remains buried within the landscape were commonly fossilised. Evidence of small animals that dug burrows (such as burrowing bettongs) and the predators that pursued them in their burrows, are exceptionally well preserved.</p>
<p>Our excavations reveal how devils and other small-to-medium sized mammals and reptiles interacted over more than 20,000 years in this area. Even during the peak arid phase, known as the Last Glacial Maximum, it seems that devils and their prey successfully co-existed.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/260575/original/file-20190224-195886-19pokrg.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/260575/original/file-20190224-195886-19pokrg.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/260575/original/file-20190224-195886-19pokrg.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=427&fit=crop&dpr=1 600w, https://images.theconversation.com/files/260575/original/file-20190224-195886-19pokrg.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=427&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/260575/original/file-20190224-195886-19pokrg.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=427&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/260575/original/file-20190224-195886-19pokrg.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=537&fit=crop&dpr=1 754w, https://images.theconversation.com/files/260575/original/file-20190224-195886-19pokrg.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=537&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/260575/original/file-20190224-195886-19pokrg.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=537&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 fossil record (10,000 to 4,000 years ago): This shows the fauna reference condition prior to the arrival of the dingo. (1 Western Quoll, 2 Tasmanian Devil, 3 Thylacine, 4 Bilby, 5 Western Barred Bandicoot, 6 Southern Brown Bandicoot, 7 Burrowing Bettong, 8 Brush Tailed Bettong, 9 Wombat, 10 Nail-Tailed Wallaby, 11 Hare Wallaby, 12 Western and Eastern Grey Kangaroo, 13 Red Kangaroo, 14 Crest Tailed Mulgara, 15 Greater Stick Nest Rat, 16 Hopping Mouse, 17 Fox, 18 Cat, 19 Rabbit)</span>
<span class="attribution"><span class="source">Toot Toot Design</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/260574/original/file-20190224-195864-7ugxh8.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/260574/original/file-20190224-195864-7ugxh8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/260574/original/file-20190224-195864-7ugxh8.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=422&fit=crop&dpr=1 600w, https://images.theconversation.com/files/260574/original/file-20190224-195864-7ugxh8.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=422&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/260574/original/file-20190224-195864-7ugxh8.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=422&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/260574/original/file-20190224-195864-7ugxh8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=530&fit=crop&dpr=1 754w, https://images.theconversation.com/files/260574/original/file-20190224-195864-7ugxh8.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=530&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/260574/original/file-20190224-195864-7ugxh8.png?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 contemporary record: This shows today’s situation in the Willandra Lakes World Heritage Area. Light grey animals represent those animals that are now locally extinct.</span>
<span class="attribution"><span class="source">Toot Toot Design</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The fossil record shows that the range of habitats occupied by devils in the past was far more diverse than today, with populations being found across environments from the central arid core to the northern tropics.</p>
<p>This suggests that devils today should, theoretically, be able to reoccupy a similarly extensive range of habitats. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/260348/original/file-20190222-195853-q9ys4g.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/260348/original/file-20190222-195853-q9ys4g.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/260348/original/file-20190222-195853-q9ys4g.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=502&fit=crop&dpr=1 600w, https://images.theconversation.com/files/260348/original/file-20190222-195853-q9ys4g.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=502&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/260348/original/file-20190222-195853-q9ys4g.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=502&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/260348/original/file-20190222-195853-q9ys4g.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=631&fit=crop&dpr=1 754w, https://images.theconversation.com/files/260348/original/file-20190222-195853-q9ys4g.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=631&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/260348/original/file-20190222-195853-q9ys4g.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=631&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Former devil range across Australia as revealed by the known fossil record.</span>
<span class="attribution"><span class="source">Toot Toot Design</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Better the devil you know</h2>
<p><a href="https://www.smh.com.au/technology/reintroducing-dingoes-can-help-manage-feral-foxes-and-cats-study-suggests-20170523-gwb8e6.html">Some ecologists suggest</a> dingoes should be reintroduced into Australian habitats in order to reduce the impact of cats and foxes on native mammals.</p>
<p>One problem is that dingoes also prey on livestock. This is the reason the dingo fence was constructed during the 1880s.</p>
<p>But devils are not active predators of cattle and sheep. So reintroducing a predator that has a much longer evolutionary history with other native mammals in this country would likely receive far less opposition from pastoralists.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/deadly-disease-can-hide-from-a-tasmanian-devils-immune-system-70594">Deadly disease can 'hide' from a Tasmanian devil's immune system</a>
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</em>
</p>
<hr>
<p>A reintroduction of devils back to the mainland may be a new approach to consider for controlling the relentless, destructive march of exotic predators and restore crucial elements of Australia’s biodiversity.</p>
<p>It still needs to be demonstrated that devils can suppress the activities of cats and foxes on the mainland, as they seem to have done in Tasmania. Experiments with devils in a range of different settings would help to establish this. </p>
<p>A new research approach involving palaeontologists, conservation biologists and policy makers may help us understand how we can restore biodiversity function in Australia.</p><img src="https://counter.theconversation.com/content/63120/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Westaway receives funding from the Australian Research Council. This research was also funded by a joint Simon Fraser University and Griffith University collaboratve grant. </span></em></p><p class="fine-print"><em><span>Gilbert Price has previously received funding from the Australian Research Council for data that has been included in this article. </span></em></p>It’s often said you need to look to the past to learn about the future, and that’s what the fossil record can tell about how the Tasmanian Devil survived in the past on mainland Australia.Michael Westaway, Senior Research Fellow, Australian Research Centre for Human Evolution, Griffith UniversityGilbert Price, Lecturer in Palaeontology, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/889472017-12-11T19:13:38Z2017-12-11T19:13:38ZTasmanian tigers were going extinct before we pushed them over the edge<figure><img src="https://images.theconversation.com/files/198462/original/file-20171211-27686-lrmoci.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Gone since 1936, and ailing since long before that.</span> <span class="attribution"><span class="source">Tasmanian Museum and Art Gallery</span>, <span class="license">Author provided</span></span></figcaption></figure><p>There’s no doubt that humans killed off the <a href="https://australianmuseum.net.au/the-thylacine">Tasmanian tiger</a>. But a new genetic analysis suggests this species had been on the decline for millennia before humans arrived to drive them to extinction.</p>
<p>The Tasmanian tiger, also known as the thylacine, was unique. It was the largest marsupial predator that survived into recent times. Sadly it was hunted to extinction in the wild, and the last known Tasmanian tiger died in captivity in 1936.</p>
<p>In a <a href="http://nature.com/articles/doi:10.1038/s41559-017-0417-y">paper published in Nature Ecology and Evolution today</a>, my colleagues and I piece together its entire genetic sequence for the first time. It tells us that thylacines’ genetic health had been declining for many millennia before they first encountered human hunters.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/will-we-hunt-dingoes-to-the-brink-like-the-tasmanian-tiger-19982">Will we hunt dingoes to the brink like the Tasmanian tiger?</a>
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<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/198466/original/file-20171211-27693-1jgss5o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/198466/original/file-20171211-27693-1jgss5o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/198466/original/file-20171211-27693-1jgss5o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=738&fit=crop&dpr=1 600w, https://images.theconversation.com/files/198466/original/file-20171211-27693-1jgss5o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=738&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/198466/original/file-20171211-27693-1jgss5o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=738&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/198466/original/file-20171211-27693-1jgss5o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=927&fit=crop&dpr=1 754w, https://images.theconversation.com/files/198466/original/file-20171211-27693-1jgss5o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=927&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/198466/original/file-20171211-27693-1jgss5o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=927&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Hounded by hunters.</span>
<span class="attribution"><span class="source">Tasmanian Museum and Art Gallery</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Our research also offered the chance to study the origins of the similarity in body shape between the thylacine and dogs. The two are almost identical, despite having last shared a common ancestor more than 160 million years ago – a remarkable example of so-called “convergent evolution”. </p>
<p>Decoding the thylacine genome allowed us to ask the question: if two animals develop an identical body shape, do they also show identical changes in their DNA?</p>
<h2>Thylacine secrets</h2>
<p>These questions were previously difficult to answer. The age and storage conditions of existing specimens meant that most thylacine specimens have DNA that is highly fragmented into very short segments, which are not suitable for piecing together the entire genome.</p>
<p>We identified a 109-year-old specimen of a young pouch thylacine in the Museums Victoria collection, which had much more intact DNA than other specimens. This gave us enough pieces to put together the entire jigsaw of its genetic makeup.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/198463/original/file-20171211-27708-kte384.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/198463/original/file-20171211-27708-kte384.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/198463/original/file-20171211-27708-kte384.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=747&fit=crop&dpr=1 600w, https://images.theconversation.com/files/198463/original/file-20171211-27708-kte384.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=747&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/198463/original/file-20171211-27708-kte384.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=747&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/198463/original/file-20171211-27708-kte384.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=939&fit=crop&dpr=1 754w, https://images.theconversation.com/files/198463/original/file-20171211-27708-kte384.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=939&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/198463/original/file-20171211-27708-kte384.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=939&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 preserved young, thylacine with enough DNA to reveal its whole genome.</span>
<span class="attribution"><span class="source">Museums Victoria</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Next, we made a detailed comparison of thylacines and dogs to see just how similar they really are. We used digital imaging to compare the thylacine’s skull shape to many other mammals, and found that the thylacine was indeed very similar to various types of dog (especially the wolf and red fox), and quite different from its closest living marsupial relatives such as the numbat, Tasmanian devil, and kangaroos. </p>
<p>Our results confirmed that thylacines and dogs really are the best example of convergent evolution between two distantly related mammal species ever described.</p>
<p>We next asked whether this similarity in body form is reflected by similarity in the genes. To do this, we compared the DNA sequences of thylacine genes with those of dogs and other animals too. </p>
<p>While we found many similarities between thylacines’ and dogs’ genes, they were not significantly more similar than the same genes from other animals with different body shapes, such as Tasmanian devils and cows.</p>
<p>We therefore concluded that whatever the reason why thylacines and dogs’ skulls are so similarly shaped, it is not because evolution is driving their gene sequences to be the same. </p>
<h2>Family ties</h2>
<p>The thylacine genome also allowed us to deduce its precise position in the marsupial family tree, which has been a controversial topic.</p>
<p>Our analyses showed that the thylacine was at the root of a group called the Dasyuromorphia, which also includes the <a href="http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=294">numbat</a> and <a href="http://www.parks.tas.gov.au/?base=387">Tasmanian devil</a>. </p>
<p>By examining the amount of diversity present in the single thylacine genome, we were able to estimate its effective population size during past millennia. This demographic analysis revealed extremely low genetic diversity, suggesting that if we hadn’t hunted them into extinction the population would be in very poor genetic health, just like today’s Tasmanian devils.</p>
<p>The less diversity you have in your genome, the more susceptible you are to disease, which might be why devils have contracted the facial tumour virus, and certainly why it has been so easily spread. The thylacine would have been at a similar risk of contracting devastating diseases.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/198465/original/file-20171211-27698-1sg40zd.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/198465/original/file-20171211-27698-1sg40zd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/198465/original/file-20171211-27698-1sg40zd.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=375&fit=crop&dpr=1 600w, https://images.theconversation.com/files/198465/original/file-20171211-27698-1sg40zd.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=375&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/198465/original/file-20171211-27698-1sg40zd.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=375&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/198465/original/file-20171211-27698-1sg40zd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=471&fit=crop&dpr=1 754w, https://images.theconversation.com/files/198465/original/file-20171211-27698-1sg40zd.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=471&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/198465/original/file-20171211-27698-1sg40zd.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=471&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 last thylacine alive.</span>
<span class="attribution"><span class="source">Tasmanian Museum and Art Gallery</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>This loss in population diversity was previously thought to have occurred as a population of thylacines (and devils) became isolated on Tasmania some 15,000 years ago, when the land bridge closed between it and the mainland. </p>
<p>But our analysis suggests that the process actually began much earlier – between 70,000 and 120,000 years ago. This suggests that both the devil and thylacine populations already had very poor genetic health long before the land bridge closed.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-curiosity-can-save-species-from-extinction-52006">How curiosity can save species from extinction</a>
</strong>
</em>
</p>
<hr>
<p>Now that we know the whole genome of the Tasmanian tiger, we know much more about this extinct animal and the unique place it held in Australia’s marsupial family tree. We are expanding our analyses of the genome to determine how it came to look so similar to the dog, and to continue to learn more about the genetics of this unique marsupial apex predator.</p><img src="https://counter.theconversation.com/content/88947/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew Pask receives funding from Australian Research Council (ARC), National Health and Medical Research Council (NHMRC), The University of Melbourne. </span></em></p>The new Tasmanian tiger genome reveals some fascinating facts about this extinct marsupial, including why they were so similar to dogs, and how they were growing more vulnerable to genetic disease.Andrew Pask, Associate Professor, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/764022017-05-11T01:39:59Z2017-05-11T01:39:59ZSurvival of the fittest? Perhaps not if you’re a Tasmanian devil<figure><img src="https://images.theconversation.com/files/165792/original/image-20170419-6360-1jy4vjm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Aggressive behaviour exhibited by socially dominant Tasmanian devils may predispose them to infection with devil facial tumour disease.</span> <span class="attribution"><span class="source">Sebastien Compte/University of Tasmania</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Tasmanian devils in their prime are most likely to become infected with deadly facial tumour disease (<a href="http://www.tassiedevil.com.au/tasdevil.nsf/the-disease/979feb5f116ce371ca2576cb0011a26e">DFTD</a>), our research shows.</p>
<p>The findings, <a href="http://onlinelibrary.wiley.com/wol1/doi/10.1111/ele.12776/abstract">published today in Ecology Letters</a>, contradict conventional wisdom that <a href="http://www.sciencedirect.com/science/article/pii/S0169534709002286">infection of relatively weakened individuals</a> is commonplace in the spread and persistence of diseases.</p>
<p>Instead, it’s the devils that enjoy the highest survival and breeding success who eventually succumb to the fatal disease.</p>
<p>DFTD has had a devastating effect on devil populations in Tasmania, with the marsupial carnivore placed on the <a href="http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=299">endangered list in 2009</a>.</p>
<p>So what is it that makes the fitter devils more prone to infection?</p>
<h2>The devils in detail</h2>
<p>DFTD is unique in that it is <a href="http://www.tassiedevil.com.au/tasdevil.nsf/The-Disease/979FEB5F116CE371CA2576CB0011A26E">one of only a few known cases of transmissible cancer</a>, where the deadly tumours do not originate from the host body.</p>
<p>The disease is <a href="http://www.nature.com/nature/journal/v439/n7076/full/439549a.html">transmitted into an individual</a> when devils bite each other.</p>
<p>To track DFTD in a population, over ten years we repeatedly surveyed more than 500 wild devils, visiting the same field site at least four times per year. </p>
<p>This allowed us to study both survival and reproduction of the devils in the context of infection dynamics and tumour growth.</p>
<p>Our results add to our understanding of how DFTD spreads through devil populations, and reveal more details of how disease-induced evolution in devil populations (such as resistance to the disease) may be occurring.</p>
<p>We suggest the way disease is transmitted plays a key role in who gets infected. </p>
<p>It is the dominant devils who are more likely to engage in aggressive behaviour, such as during mating. This puts them at higher risk of biting an infected individual and thus becoming infected themselves. </p>
<p>So it’s the devils who are otherwise very fit (in the evolutionary sense) that the disease takes out. These are the ones that have the highest survival and reproduction rates, before being killed by the cancer.</p>
<h2>Impact on devil populations</h2>
<p>So what does this say about the future survival of devil populations in Tasmania’s wild?</p>
<p>Too often, a dramatic-looking disease such as DFTD leaves the impression that it must have detrimental effect on the overall population growth. </p>
<p>But this is not necessarily the case if diseased individuals had a chance to reproduce before they got infected. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/166454/original/file-20170424-23807-stwd6a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/166454/original/file-20170424-23807-stwd6a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/166454/original/file-20170424-23807-stwd6a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/166454/original/file-20170424-23807-stwd6a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/166454/original/file-20170424-23807-stwd6a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/166454/original/file-20170424-23807-stwd6a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/166454/original/file-20170424-23807-stwd6a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/166454/original/file-20170424-23807-stwd6a.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">Possible scenarios of Tasmanian devil survival and reproduction amid the risk of DFTD infection. The horizontal thick lines indicate individual devil survival over time, small devils reproduction and red dots infestation with tumours.</span>
<span class="attribution"><span class="source">David Sargent/Queensland College of Art/Griffith University</span></span>
</figcaption>
</figure>
<p>In the graphic (above) we can see that some devils may not reproduce because either (A) of their social status, or (B) if they get an infection early in life and rapid tumour growth results in death.</p>
<p>In contrast, devils who get the disease late in life (C) may have already reproduced earlier. In (D) devils may still get infected, but if the tumour grows slowly they may still have chance to reproduce before death.</p>
<p>As for healthy and dominant devils who don’t get the disease (E), they may reproduce several times in their life.</p>
<p>Such details can be vital to understand the spread of DFTD and the outcome for Tasmanian devil populations. </p>
<p>It is the complex interplay of devil demography and disease dynamics that ultimately determines whether DFTD is a conservation threat for devils. </p>
<h2>Infection decline</h2>
<p>Our <a href="http://onlinelibrary.wiley.com/wol1/doi/10.1111/ele.12776/abstract">results</a> also show a recent decline in the likelihood that devils become infected in this population. This could indicate some evolving resistance of devils to the cancer, as was <a href="https://www.nature.com/articles/ncomms12684">recently shown</a> by researchers from our team. </p>
<p>Alternatively, the decline in infection rate could have resulted from a reduction in the number of socially dominant devils, if these are responsible for most transmissions of the disease.</p>
<p>If adult devils with high fitness are those that become infected, the potential for selection for resistant animals would be limited. </p>
<p>This is because these individuals still contribute more offspring (and their genetic constitution) to future generations than those not infected and with little engagement in reproduction. </p>
<h2>Devil conservation</h2>
<p>Our findings could have an impact on some of the conservation strategies for devils, such as vaccination or translocation of devils to other areas. </p>
<p>For example, a targeted vaccination of socially dominant individuals would be more efficient than randomly picking individuals for vaccination. </p>
<p>If devil individuals from captive insurance populations were to be released into wild populations, the consequences for disease spread and population viability would be unpredictable without a better understanding of the role of social behaviour in disease transmission. </p>
<p>If introduced individuals distract existing social structure and more frequently engage in biting behaviour, they may favour the spread of DFTD. </p>
<p>If devils develop resistance to DFTD, the introduction of individuals from captive populations may dilute the natural selection process.</p>
<p>Our study suggest that DFTD appears to be selectively spread and does not affect all individuals in a population. Understanding disease transmission pathways is a prerequisite to aid conservation efforts to stop the spread of unwanted diseases.</p><img src="https://counter.theconversation.com/content/76402/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew Storfer receives funding from US National Science Foundation</span></em></p><p class="fine-print"><em><span>Hamish McCallum receives funding from the National Science Foundation (USA)</span></em></p><p class="fine-print"><em><span>Menna Elizabeth Jones receives funding from the Australian Research Council. She is affiliated with Science and Technology Australia in the capacity of President of the Australian Mammal Society. </span></em></p><p class="fine-print"><em><span>Paul Hohenlohe receives funding from the National Science Foundation (USA) and the National Institutes of Health (USA). </span></em></p><p class="fine-print"><em><span>Rodrigo Hamede receives funding from Australian Research Council (DECRA Fellowship)
</span></em></p><p class="fine-print"><em><span>Douglas Kerlin and Konstans Wells do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>It’s the Tasmanian devils that enjoy the highest survival and breeding success who’re more likely to get the fatal facial tumour disease.Konstans Wells, Research Fellow in Ecology, Griffith UniversityAndrew Storfer, Professor & Associate Director, School of Biological Sciences, Washington State UniversityDouglas Kerlin, Postdoctoral Reseach Fellow, Environmental Futures Research Institute, Griffith UniversityHamish McCallum, Professor, Griffith School of Environment and Acting Dean of Research, Griffith Sciences, Griffith UniversityMenna Elizabeth Jones, Associate professor, University of TasmaniaPaul Hohenlohe, University of IdahoRodrigo Hamede, Post Doctoral Research Fellow, Conservation Biology and Wildlife Management, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/705942016-12-20T19:04:50Z2016-12-20T19:04:50ZDeadly disease can ‘hide’ from a Tasmanian devil’s immune system<figure><img src="https://images.theconversation.com/files/150829/original/image-20161219-24310-1pornqc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The deadly facial tumour can hide itself from the Tasmanian devil's immune system.</span> <span class="attribution"><span class="source">Andrew Flies</span>, <span class="license">Author provided</span></span></figcaption></figure><p>The Tasmanian devil facial tumour (<a href="http://www.tassiedevil.com.au/tasdevil.nsf/The-Disease/979FEB5F116CE371CA2576CB0011A26E">DFT</a>) cells may use a molecular deception – common in human cancers – that could allow the deadly disease to avoid the animal’s immune system, according to our <a href="http://journal.frontiersin.org/article/10.3389/fimmu.2016.00581/abstract">new research</a> published this month.</p>
<p>Recently it was discovered that <a href="http://www.pnas.org/content/early/2013/03/06/1219920110.abstract">DFT cells effectively hide</a> from the immune system by not expressing key immune recognition molecules.</p>
<p>Our new discovery that DFT cells contain this “molecular shield” in response to inflammation represents another important step towards understanding the disease and developing more potent ways of preventing or treating it. </p>
<p>So how does this shield work? First, we need to look at some of the recent developments in the treatment of cancers in general. </p>
<h2>Cancer treatments</h2>
<p>Cancer treatment has undergone a revolution in recent years. Gone are the days when surgery and harsh chemotherapy regimens are the only options. </p>
<p>Now cancer immunotherapy can stimulate the immune system to kill cancer cells. In 2013 this was named the <a href="http://science.sciencemag.org/content/342/6165/1432.full">breakthrough of the year</a> in one of the top science journals in the world.</p>
<p>Since 2013 the immunotherapies that target what we call immune checkpoint molecules have continued to make <a href="http://www.cancerresearch.org/our-strategy-impact/timeline-of-progress/timeline-detail">great progress</a> and have recently been approved as first line defences for some cancers.</p>
<p>Checkpoint molecules are critical for keeping the immune system in balance. Every time that the accelerator is pressed in the immune system, there is always at least one, and often several, means of stepping on the brakes. </p>
<p>These checks and balances are necessary because even though the primary job of the immune system is to protect us from disease, the immune system wields powerful weapons that can inflict collateral damage to critical tissues and organ systems when it is aimed at the wrong target. </p>
<h2>Programmed death</h2>
<p>In recent years the aptly-named checkpoint molecules – “programmed death-1” (PD-1) and “programmed death ligand 1” (PD-L1) – have emerged to be critical regulators of the anti-cancer immune response.</p>
<p>The PD-L1 molecule is used by many types of cancer as a <a href="http://www.bloodjournal.org/content/111/7/3635">molecular shield</a> to protect the malignant cells from anti-cancer immune responses. </p>
<p>The PD-1 molecule is found on several types of immune cells, but has particular relevance to the anti-cancer responses mediated by T cells.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/ntk8XsxVDi0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>When PD-1 on a cancer-killing T cell interacts with PD-L1 on cancer cells, the T cell is shut off. The T cell may undergo programmed death or it may linger and play no role in the anti-cancer response.</p>
<p>The worst possibility is that the former cancer-killing T cell hangs around and actually prevents other immune cells from killing cancer cells.</p>
<h2>The Tassie devil’s immune system</h2>
<p>Our Tasmanian devil immunology team has recently demonstrated that these critical immune checkpoint molecules are also <a href="http://journal.frontiersin.org/article/10.3389/fimmu.2016.00581/abstract">present in devils</a>. This may play a role in the ability of the DFT’s ability to evade the devil immune system.</p>
<p>There likely exists many additional mechanisms that the DFTs use to hide from or suppress the immune system of devils and ongoing research efforts aim to uncover and neutralise these mechanisms.</p>
<p>Recent evidence has shown that some devils have <a href="http://rsbl.royalsocietypublishing.org/content/12/10/20160553">tumour regressions</a>, showing that the tumours are not always able to hide from the immune system. </p>
<p><a href="https://theconversation.com/why-do-some-cancers-suddenly-disappear-57226">Spontaneous tumour regression</a> is not common in humans, but it does occur in some people and is likely caused by the immune system recognising and killing tumour cells. </p>
<h2>Another deadly disease</h2>
<p>But the devils are not out of the woods yet for a few reasons. Only in 2014 a <a href="http://www.pnas.org/content/113/2/374.abstract">second transmissible cancer</a> (devil facial tumour disease 2 or DFT2) was discovered in wild devils in southern Tasmania. </p>
<p>There are only a handful of naturally transmissible tumours known in the world, so a second transmissible tumour in devils is extremely surprising, like lightning striking the devils twice. </p>
<p>In order for the wild devil population to be truly safe from the transmissible tumours, they would need to have immunity to both the original transmissible tumour DFT and DFT2 and hope that no new transmissible cancers arise.</p>
<p>It remains unknown at this point how many different weapons the tumours use to evade or suppress the immune system. </p>
<p>The tumours themselves can also evolve rapidly in response to ecological and immunological pressure. In many cases, disease causing agents evolve to be less virulent (not kill the animal they infect), but only time will tell if that will happen in the curious case of the devil.</p>
<p>Our ongoing research aims to understand exactly which devil immune system switches can be turned on and off in order to stimulate immune cells to kill cancer cells.</p>
<p>This will be particularly fruitful if we can pinpoint specific genetic and immunological mechanisms that are different in devils that kill tumour cells and those that don’t.</p>
<p>It’s not often that you cheer for the devil, but this is one situation where nearly everybody wants the devil to win!</p><img src="https://counter.theconversation.com/content/70594/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew S. Flies has received funding from Morris Animal Foundation, Sansom Institute for Health Research - University of South Australia, Menzies Institute for Medical Research, and currently receives funding from the University of Tasmania Foundation through funds raised by the Save the Tasmanian Devil Appeal, and an Innovation Connections Grant with Nextvet BioPharma Pty Ltd.</span></em></p><p class="fine-print"><em><span>Greg Woods has received funding from the Australian Research Council, Mazda Foundation and currently receives funding from University of Tasmania Foundation through funds raised by the Save the Tasmanian Devil Appeal, Holsworth Wildlife Research Endowment, and an Innovation Connections Grant with Nextvet BioPharma Pty Ltd. </span></em></p>The facial tumour cells that threaten the Tasmanian devils may use a sort of molecular shield to protect them from the animal’s immune system.Andrew S. Flies, Postdoctoral Research Fellow in Immunology, University of TasmaniaGreg Woods, Professional Research Fellow, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/680582016-11-13T19:05:24Z2016-11-13T19:05:24ZTasmanian devils reared in captivity show they can thrive in the wild<figure><img src="https://images.theconversation.com/files/144741/original/image-20161106-27947-nukkxg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Devils released back onto the Tasmanian mainland in the next step to fight the deadly DFTD disease.</span> <span class="attribution"><span class="source">Wildlife Management Branch, Department of Primary Industries, Parks, Water and Environment</span>, <span class="license">Author provided</span></span></figcaption></figure><p>One of the concerns of any conservation breeding program is how well a species raised in captivity will survive when released into the wild.</p>
<p>Evolutionary changes that are beneficial for an individual while in captivity may reduce its fitness when translocated to the wild.</p>
<p>For some species, like many fish, <a href="http://www.pnas.org/content/109/1/238.full">rapid evolutionary changes</a> can occur within the first generation in captivity. And carnivores raised in captivity have a low chance of surviving the first year following their release. </p>
<p>A review of 45 carnivore translocations, which included 17 different species, including the European lynx, European otter and the swift fox, found that if the animals had been raised in captivity they had on average a <a href="http://www.sciencedirect.com/science/article/pii/S0006320707004417">30% chance of survival</a> after release.</p>
<h2>Save the devil program</h2>
<p>All this was a concern then for efforts to help save the Tasmanian devil.</p>
<p>The devil plays an important functional role within the Tasmanian ecosystem and is the last of the large marsupial carnivores. </p>
<p>But the Tasmanian devil is <a href="http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=299">listed as endangered</a> and their population has declined by 80% over the past ten years. This is due largely to the infectious fatal cancer, <a href="http://onlinelibrary.wiley.com/doi/10.1890/08-1763.1/full">the devil facial tumour disease</a> (DFTD). </p>
<p>As part of a conservation effort, a disease-free devil population has been established in captivity. </p>
<p>But given the low rate of survival of released captive-raised carnivores in other conservation programs it was important to identify whether their release could play a viable role in the conservation of the Tasmanian devil.</p>
<p>Captive breeding programs are extremely expensive and resource allocation was very tight. So more than 35 institutions helped to set up the captive devil insurance population. </p>
<p>Different types of enclosure setting were used, some intensive zoo style while others had larger pens to allow for a more free range style. The different enclosure types offered different opportunities for the devils to retain their natural behaviours.</p>
<p>We tested the effect of the various captive-rearing methods on the survival and body mass of captive raised Tasmanian devils that were released on Maria Island, off Tasmania’s east coast. </p>
<p>Our study, <a href="http://www.publish.csiro.au/WR/fulltext/WR15221">published this month</a> in CSIRO Wildlife Research, showed that Tasmanian devils raised in captivity before being translocated into the wild had a high survival success (96%). Most of the devils are still alive two years after their release. </p>
<p>The devils gained weight, are hunting and breeding. This is irrespective of the type of captive-rearing method as both zoo style and free range reared animals are thriving. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/144752/original/image-20161106-27925-wnc26h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/144752/original/image-20161106-27925-wnc26h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/144752/original/image-20161106-27925-wnc26h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=423&fit=crop&dpr=1 600w, https://images.theconversation.com/files/144752/original/image-20161106-27925-wnc26h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=423&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/144752/original/image-20161106-27925-wnc26h.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=423&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/144752/original/image-20161106-27925-wnc26h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=532&fit=crop&dpr=1 754w, https://images.theconversation.com/files/144752/original/image-20161106-27925-wnc26h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=532&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/144752/original/image-20161106-27925-wnc26h.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=532&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Release of the devils.</span>
<span class="attribution"><span class="source">Wildlife Management Branch, Department of Primary Industries, Parks, Water and Environment</span></span>
</figcaption>
</figure>
<h2>Natural born killers</h2>
<p>One cause of translocation failure in other programs has been that the released animals starve. The captive-raised animals had not learnt foraging and hunting skills. Some carnivorous mammals can lose this natural foraging behaviour in captivity. </p>
<p>But the captive-raised Tasmanian devils adjusted to the wild better than other carnivorous species. This was not only because they were released in the relative safety of an island, but it suggests that the devils’ foraging behaviour does not need to be learnt.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/144739/original/image-20161106-27925-3nzczf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/144739/original/image-20161106-27925-3nzczf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/144739/original/image-20161106-27925-3nzczf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/144739/original/image-20161106-27925-3nzczf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/144739/original/image-20161106-27925-3nzczf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/144739/original/image-20161106-27925-3nzczf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/144739/original/image-20161106-27925-3nzczf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/144739/original/image-20161106-27925-3nzczf.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">Devils have bone crushing jaws.</span>
<span class="attribution"><span class="source">Wildlife Management Branch, Department of Primary Industries, Parks, Water and Environment.</span></span>
</figcaption>
</figure>
<p>Devils have a <a href="http://onlinelibrary.wiley.com/wol1/doi/10.1111/j.1469-7998.2011.00844.x/full">massive head with bone crushing jaws</a>, large tough molars and strong shoulders and neck. They have a very broad approach to what they will eat.</p>
<p>Their diet includes all major critters such as mammals, birds, reptiles, amphibians and invertebrates. Devils have been seen catching gum moths out of the air, slurping tadpoles out of ponds and digging yabbies out of their burrows.</p>
<p>They also live from the intertidal zone to the sub alpine zone. They climb trees like a possum and are good swimmers.</p>
<p>There was less carrion available on Maria Island than on the mainland. Also the captive-raised devils would not have learnt hunting skills while in captivity so we presumed that they would not eat large prey.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/lMaIVaiCHDM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Captive devils feeding upon a carcass.</span></figcaption>
</figure>
<p>Initially, after the first release, the devils fed on brushtail possums. But relatively soon after we found the devils started to feed on large prey, such as the common wombat and eastern grey kangaroo. These species are <a href="http://onlinelibrary.wiley.com/doi/10.1111/jeb.12936/full">much larger than you would predict</a> for a mammal of the devils’ size to prey on. </p>
<h2>What’s planned for the devils?</h2>
<p>So what does the success of this wild release say for the future conservation of the Tasmanian devil?</p>
<p>The devil facial tumour disease has been detected across the majority of the devil’s range. The wild devil population has been decimated as the disease moved across Tasmania. </p>
<p>It is time to boost the genetic diversity of the wild population. We need to provide the potential for immunity to develop in the species. That’s why it is exciting to have found that the captive-raised devils adjusted so well in the wild. </p>
<p>The next step will be to supplement the wild Tasmanian mainland population by releasing further captive-raised devils, along with those born wild on Maria Island.</p>
<p>But the devils released on the Tasmanian mainland will face other dangers. Alongside the disease they will have to contend with dogs, rodent poison and car collisions.</p>
<p>Clearly there’s some work still to be done, but the Maria Island and captive devils will continue to be an important part of the fight against the deadly facial tumour.</p><img src="https://counter.theconversation.com/content/68058/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tracey Rogers receives funding from ARC. </span></em></p>Some animals bred in captivity often lack the skills needed to survive in the wild. But the Tasmanian devil is showing it’s a natural born killer.Tracey Rogers, Associate Professor Evolution & Ecology, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/644232016-08-30T20:14:38Z2016-08-30T20:14:38ZTasmanian devils are evolving rapidly to fight their deadly cancer<figure><img src="https://images.theconversation.com/files/135714/original/image-20160829-17862-1pz5qa7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A healthy devil. </span> <span class="attribution"><span class="source">Menna Jones</span></span></figcaption></figure><p>For the past 20 years, an infectious cancer has been killing wild Tasmanian devils, creating a massive challenge for conservationists. But <a href="http://dx.doi.org/10.1038/ncomms12684">new research</a>, published today in Nature Communications, suggests that devils are evolving rapidly in response to their highly lethal transmissible cancer and that they could ultimately save themselves. </p>
<p>Cancer is usually a disease that arises and dies with its host. In vertebrates, only <a href="http://www.nature.com/onc/journal/v27/n2s/full/onc2009350a.html">two known types</a> – Canine Transmissible Venereal Cancer in dogs and Devil Facial Tumour Disease (DFTD) – have taken the extraordinary evolutionary step of becoming transmissible. These cancers can grow not just within their host but can spread to other individuals. Because the cancer cells are all descendants of one mutant cell, the cancer is effectively immortal.</p>
<p>To grow in the new host, the tumour cell must evade detection and rejection by the immune system. Both the devil and dog transmissible cancers have <a href="http://www.pnas.org/content/110/13/5103.full">sophisticated mechanisms for hiding</a> from the host’s immune system. Our research suggests that the devil is nevertheless evolving resistance to the disease.</p>
<h2>Ecological disaster</h2>
<p>The Tasmanian devil is too important to lose – and <a href="http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.0040342">this would seem careless</a> following the extinction of the thylacine, the world’s largest marsupial predator, in the 1930s. Since the thylacine’s extinction, devils have stepped up to the role of top marsupial predator, keeping numbers of destructive feral cats at bay in Tasmania. With the decline of the devils, <a href="http://onlinelibrary.wiley.com/doi/10.1890/15-0204.1/abstract;jsessionid=715ADED667A4258DC6DD6ECDD29EE6E0.f02t03">invasive species have become more active</a>. </p>
<p>Since it was first detected in northeastern Tasmania in the mid-1990s, DFTD has spread slowly southward and westward. It will reach all parts of Tasmania within a few years; only the far northwest coast and parts of the southwest are still disease-free. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/135894/original/image-20160830-28253-14rvo8m.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/135894/original/image-20160830-28253-14rvo8m.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/135894/original/image-20160830-28253-14rvo8m.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=550&fit=crop&dpr=1 600w, https://images.theconversation.com/files/135894/original/image-20160830-28253-14rvo8m.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=550&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/135894/original/image-20160830-28253-14rvo8m.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=550&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/135894/original/image-20160830-28253-14rvo8m.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=691&fit=crop&dpr=1 754w, https://images.theconversation.com/files/135894/original/image-20160830-28253-14rvo8m.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=691&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/135894/original/image-20160830-28253-14rvo8m.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=691&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Devil Facial Tumour Disease has spread across the island over two decades.</span>
<span class="attribution"><span class="source">Menna Jones</span></span>
</figcaption>
</figure>
<p>Devil populations have declined <a href="http://www.tassiedevil.com.au/tasdevil.nsf">by at least 80%</a>, and by <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2656.2007.01272.x/full">more than 90% in some areas</a> within six years of local disease outbreak. </p>
<p>DFTD kills most devils at sexual maturity. Before the disease arrived, most devils produced three litters over their lifetime. Most <a href="http://www.pnas.org/content/105/29/10023.full?sid=5d14d3b2-71e6-4409-ab97-235c7f06659f">now raise only one</a>. </p>
<p>The cascading effects of the loss of Tasmania’s top predator on the rest of the ecosystem could lead to loss of further species. Already, <a href="http://onlinelibrary.wiley.com/doi/10.1890/15-0204.1/abstract">feral cats have increased activity</a> and small mammals on which cats prey have declined. </p>
<p><a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0119303">Cats may also be preventing recovery</a> of the eastern quoll. Brushtail possums behave as if devils <a href="http://rspb.royalsocietypublishing.org/content/royprsb/282/1810/20150124.full.pdf">were already extinct</a>, grazing freely on pasture in the open.</p>
<h2>Evolution in action</h2>
<p>Our research has been a truly international effort. We used data collected by Menna Jones at the University of Tasmania since 1999. This archive of tissue samples now represents one of the best resources globally for studying evolution of an emerging infectious disease in wildlife.</p>
<p>Andrew Storfer at Washington State University and Paul Hohenlohe at the University of Idaho compared the frequency of genes in devils in regions before DFTD arrived to devils 8-16 years after DFTD arrived. </p>
<p>We identified significant changes in two small regions in the DNA samples of devils from regions with DFTD. Five of seven genes in the two regions were related to cancer or immune function in other mammals, suggesting that Tasmanian devils are indeed evolving resistance to DFTD. Evolution is often thought of as a slow process, but these changes have occurred in as few as 4–8 generations of devils since disease outbreak.</p>
<p>Devils are surviving at our long-term sites, despite models that <a href="http://onlinelibrary.wiley.com/doi/10.1890/08-1763.1/full">predicted extinction</a>. Previously, studies have shown that devils with lower rates of DFTD showed <a href="http://www.nature.com/articles/srep25093">specific changes in their immune response</a>. Our genetic results might explain why.</p>
<p>New infectious diseases put strong pressure on their hosts to evolve, <a href="http://www.cell.com/trends/ecology-evolution/fulltext/S0169-5347(03)00260-X">leading to rapid changes</a> in resistance or tolerance. Rapid evolution requires pre-existing genetic variation. Our results are surprising because Tasmanian devils have <a href="http://www.pnas.org/content/108/30/12348.full?sid=76eec8cf-eadb-4b0e-805a-d4de96d018a6">low levels of genetic diversity</a>. </p>
<p>Evolution doesn’t just act on the devils; it also also acts on the disease. The disease evolves to not kill the host before it can spread to another host, but also to overcome the host’s defences. Over the long term, pathogen (the cause of the disease) and host usually evolve to live together as <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4379559/">rabbits and Myxoma virus have evolved together</a>. </p>
<p>Our results suggest that devils in the wild may save themselves through evolution. However, it is essential for managers to develop strategies that help the devils do so. For example, releasing fully susceptible devils that have had no exposure to the disease into populations where resistance is developing is likely to be counterproductive. </p>
<p>DFTD presents a unique opportunity to study the early stages of the evolution of a new disease and transmissible cancer with its animal host. Ultimately, through future research, we may understand how cancers can become transmissible and how their hosts respond.</p><img src="https://counter.theconversation.com/content/64423/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Menna Elizabeth Jones receives funding from the Australian Research Council, the US National Science Foundation and the Save the Tasmanian Devil Appeal. </span></em></p><p class="fine-print"><em><span>Andrew Storfer receives funding from US National Science Foundation</span></em></p><p class="fine-print"><em><span>Hamish McCallum receives funding from the US National Science Foundation, the Australian Research Council and the Queensland Government. </span></em></p><p class="fine-print"><em><span>Paul Hohenlohe receives funding from the US National Science Foundation and the US National Institutes of Health. </span></em></p><p class="fine-print"><em><span>Rodrigo Hamede receives funding from University of Tasmania Foundation, the US National Science Foundation and the Save the Tasmanian devil Program.
School of Biological Sciences, University of Tasmania. Australia</span></em></p>New research suggests devils are evolving rapidly in response to their highly lethal transmissible cancer, and that the devils could save themselves.Menna Elizabeth Jones, Associate professor, University of TasmaniaAndrew Storfer, Professor & Associate Director, School of Biological Sciences, Washington State UniversityHamish McCallum, Professor, Griffith School of Environment and Acting Dean of Research, Griffith Sciences, Griffith UniversityPaul Hohenlohe, University of IdahoRodrigo Hamede, Post Doctoral Research Fellow, Conservation Biology and Wildlife Management, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/431212015-08-23T19:48:33Z2015-08-23T19:48:33ZBringing devils back to the mainland could help wildlife conservation<figure><img src="https://images.theconversation.com/files/92654/original/image-20150821-15919-1aesd0h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">This furry critter could help save plenty of others, if given the chance.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File%3ASarcophilus_harrisii_-Cleland_Wildlife_Park-8a.jpg">Chen Wu/Flickr/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Australia’s mammal extinction crisis needs urgent attention. Foxes and cats have significantly contributed to the loss of some of our most vulnerable species. Alarmingly, the trend doesn’t look like slowing.</p>
<p>Many researchers agree that the dingo plays an important role in mitigating native mammal declines, because they suppress foxes and, in some cases, cats. So when we remove dingoes to benefit livestock, our native wildlife suffers.</p>
<p>This leaves environmental managers in a difficult situation, because what’s best for a livestock farmer isn’t best for conservation. But our research, <a href="http://www.sciencedirect.com/science/article/pii/S0006320715300379">published this month in Biological Conservation</a>, suggests that devils could help slow native mammal declines on the mainland with negligible harm to livestock.</p>
<h2>Top predators</h2>
<p><a href="http://onlinelibrary.wiley.com/doi/10.1111/cobi.12152/full">Research suggests</a> that devils play an important top predator role in Tasmania. So we modelled what would happen if we reintroduced them back to the mainland, where they existed until quite recently – probably <a href="http://www.tandfonline.com/doi/abs/10.1080/03115510609506855#.Vda4wSyqqko">around 3,000 years ago</a>. We found that devils have important ecosystem effects that are similar to, but weaker than, those of dingoes.</p>
<p>Specifically, our modelling suggested that reintroducing devils to the mainland would lead to reductions in fox and cat numbers. Foxes and cats are arguably the greatest living threat to our native mammals, so any reduction in their abundance is going to be of great benefit to our struggling native mammal species.</p>
<p>Overabundance of large herbivores is also a problem in areas without large predators. Our models show that devils, like dingoes, negatively affect wombats, kangaroos and wallabies. The regulation of large herbivores would increase the available food and shelter for our small and medium-sized native mammals. </p>
<p>Essentially, our models show that devils can help maintain a state of ecosystem equilibrium in the absence of dingoes. But there’s another reason why a devil reintroduction could benefit biodiversity conservation. </p>
<p>Devils themselves are facing a real extinction threat from <a href="http://www.ncbi.nlm.nih.gov/pubmed/22341448">devil facial tumour disease</a>. A disease-free mainland population of devils would be an excellent form of insurance if the species were to become extinct in Tasmania.</p>
<h2>Where could devils be introduced?</h2>
<p>Our modelling showed that there is plenty of suitable devil habitat in eastern Australia. Much of the Great Dividing Range provides similar conditions to where devils are currently found in Tasmania. </p>
<p>It is likely that dingoes contributed to the extinction of devils from the mainland in the first place, aided by an increase in <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1469-185X.2011.00203.x/full">human persecution of devils</a>. With devils now protected, the threat from humans is now largely gone, leaving dingoes as the only main threat. </p>
<p>However, we provided maps showing areas where dingoes are absent or functionally extinct which could provide potentially suitable reintroduction sites. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/92708/original/image-20150821-31397-4kmu22.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/92708/original/image-20150821-31397-4kmu22.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=278&fit=crop&dpr=1 600w, https://images.theconversation.com/files/92708/original/image-20150821-31397-4kmu22.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=278&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/92708/original/image-20150821-31397-4kmu22.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=278&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/92708/original/image-20150821-31397-4kmu22.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=350&fit=crop&dpr=1 754w, https://images.theconversation.com/files/92708/original/image-20150821-31397-4kmu22.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=350&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/92708/original/image-20150821-31397-4kmu22.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=350&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">(a) Predicted suitable devil habitat on the mainland, and (b) the distribution of all wild dogs (including dingoes) on the Australian mainland.</span>
<span class="attribution"><span class="source">Modified from Letnic et al. 2011</span></span>
</figcaption>
</figure>
<p>Devils are not as great a threat to livestock as are dingoes. Their impact is more similar to that of foxes, with young sheep most at risk. Therefore, a reintroduction is likely to garner more support from farmers than the alternative of actively maintaining dingo populations.</p>
<h2>Making it happen</h2>
<p>The next step is to test our model predictions with a carefully controlled, free-ranging captive trial. With many native species under serious threat, we urge land managers to begin planning now.</p>
<p>Undoubtedly there are some risks associated with reintroducing devils, but the risks of inaction are far greater. Because devils lived on the mainland until recently, our native species have already evolved to live alongside it. There is little doubt that the net negative effect of devils on native mammals will be far less than that of foxes and cats.</p>
<p>Our native mammal species are in serious trouble. We need to explore bold, new solutions to our conservation challenges. If we don’t restore ecosystems and their predator networks now, we risk losing even more of our native mammal species.</p>
<p><em>Dr Thomas Britz (UNSW Australia) and Assoicate Professor Menna Jones (University of Tasmania) also contributed to the research described in this article.</em></p><img src="https://counter.theconversation.com/content/43121/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Daniel Hunter receives funding from the Blue Mountains World Heritage Institute top-up scholarship</span></em></p><p class="fine-print"><em><span>Mike Letnic receives funding from the Australian Research Council.</span></em></p>If we brought devils back to the mainland, they could play a similar role to dingoes - keeping foxes and cats under control and potentially boosting the conservation prospects of Australia’s small mammals.Daniel Hunter, PhD candidate , UNSW SydneyMike Letnic, Associate Professor, School of Biological, Earth and Environmental Sciences, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/371512015-03-12T04:32:04Z2015-03-12T04:32:04ZCan Tassie devils control feral cats? The devil is in the detail<figure><img src="https://images.theconversation.com/files/72753/original/image-20150223-32238-izrian.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Could devils help solve our feral cat crisis? The devil might be in the detail.</span> <span class="attribution"><span class="source">Ross Huggett/Flickr</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Recently there have been discussions around <a href="https://theconversation.com/should-we-move-tasmanian-devils-back-to-the-mainland-16388">reintroducing Tasmanian devils</a> to parts of the Australian mainland. Some have even predicted that devils could help conserve biodiversity by <a href="http://www.abc.net.au/radionational/programs/scienceshow/devils-on-the-mainland-promise-to-control-foxes2c-cats2c-savi/5987756#transcript">controlling the feral cats and foxes</a> that currently prey on a range of threatened species.</p>
<p>Some of these predicted benefits are said to be based on <a href="https://theconversation.com/should-we-move-tasmanian-devils-back-to-the-mainland-16388">“evidence from Tasmania”</a>. But how much evidence do we really have?</p>
<p>As part of a study investigating the cause of <a href="http://www.publish.csiro.au/nid/256/paper/AM13004.htm">decline of the eastern quoll</a>, we and our colleagues investigated interactions between devils, feral cats and quolls in Tasmania. Our findings published today in <a href="http://dx.plos.org/10.1371/journal.pone.0119303">PLOS ONE</a> suggest that there’s no easy answer to the devil and cat conundrum. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/72674/original/image-20150221-21879-13vu74k.gif?ixlib=rb-1.1.0&rect=33%2C4%2C641%2C491&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/72674/original/image-20150221-21879-13vu74k.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/72674/original/image-20150221-21879-13vu74k.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/72674/original/image-20150221-21879-13vu74k.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/72674/original/image-20150221-21879-13vu74k.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/72674/original/image-20150221-21879-13vu74k.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/72674/original/image-20150221-21879-13vu74k.gif?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">A feral cat walks between feeding devils in a Tasmanian free range enclosure, but how much do we know about their interactions in the wild?</span>
<span class="attribution"><span class="source">Simon Plowright/Bicheno FRE, Natureworld</span></span>
</figcaption>
</figure>
<h2>What’s the link between cats and devils?</h2>
<p>In Tasmania, it has been <a href="http://link.springer.com/article/10.1007/s10393-007-0120-6">suggested</a> that devils may control feral cats through competition and possibly predation. With devil populations currently being <a href="http://www.sciencedirect.com/science/article/pii/S0006320706001595">decimated</a> by the spread of the fatal <a href="https://theconversation.com/tassie-devil-facial-tumour-is-a-transmissible-cancer-34312">Devil Facial Tumour Disease</a> (DFTD), it was predicted that devil declines would allow <a href="http://link.springer.com/article/10.1007/s10393-007-0120-6">feral cat numbers to increase</a>, threatening a range of small and medium-sized prey species.</p>
<p>In north east Tasmania (where DFTD was <a href="http://www.tassiedevil.com.au/tasdevil.nsf/The-Disease/979FEB5F116CE371CA2576CB0011A26E">first detected in 1996</a> and devils have been in decline the longest), government spotlight surveys detected an <a href="http://onlinelibrary.wiley.com/doi/10.1111/cobi.12152/abstract">increase in cat sightings</a> following devil decline.</p>
<p>This increase in cat sightings has often been interpreted as an increase in cat numbers, with suggestions that <a href="http://onlinelibrary.wiley.com/doi/10.1111/cobi.12152/abstract">eastern quoll declines may then be linked to an increase in cats</a>. While this interpretation might fit with predictions, our findings suggest that such conclusions may be premature.</p>
<p>Contrary to predictions, we found <a href="http://dx.plos.org/10.1371/journal.pone.0119303">no support</a> for the hypothesis that devils control cat numbers. Sites with more devils did not have fewer cats, and conversely, sites with fewer devils did not have more cats. </p>
<p>Further, we did not find higher cat numbers in north east Tasmania where devils had declined for 13-16 years.</p>
<p>So how do we explain the increase in cat sightings?</p>
<h2>Scaredy cats</h2>
<p>Devils might not control the number of cats – but they may affect their behaviour.</p>
<p>The key for predators to co-exist is avoidance. By concentrating activity into <a href="http://www.bioone.org/doi/abs/10.3957/056.039.0207">times</a> and <a href="http://onlinelibrary.wiley.com/doi/10.1111/1365-2656.12231/abstract">places</a> where large predators are less active, smaller predators such as cats reduce the risk of aggressive encounters with larger predators such as devils.</p>
<p>In our study, we found that cats and devils used the same areas, with cats observed at 92% of sites where devils were detected. While cats appeared to avoid individual cameras where devils were detected (a finding consistent with <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0059846">other studies</a>), they were usually detected on cameras located only a few hundred metres away at the same site. This suggests that cats may avoid areas where devils are active, but only over short distances.</p>
<p>We also found evidence that cats and devils were active at different times. Cats were more active during the day, but in north east Tasmania where devils have been in decline the longest, cats were more active at night.</p>
<p>This suggests that cats may have previously hunted during the day to avoid nocturnally active devils. But with fewer devils to encounter following DFTD, it may now be safer for cats to shift their activity and hunt at night.</p>
<p>Even without an increase in cat numbers, this apparent shift in cat activity presents an emerging threat to a range of nocturnal prey species that may have rarely seen cats prior to DFTD. </p>
<p>If cats are now more active at night following devil decline, the increase in cat sightings in north east Tasmania may simply reflect a shift in cat activity times, with nocturnal cats now more detectable in spotlight surveys conducted at night.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/71387/original/image-20150208-28578-1laxp18.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/71387/original/image-20150208-28578-1laxp18.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/71387/original/image-20150208-28578-1laxp18.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=250&fit=crop&dpr=1 600w, https://images.theconversation.com/files/71387/original/image-20150208-28578-1laxp18.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=250&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/71387/original/image-20150208-28578-1laxp18.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=250&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/71387/original/image-20150208-28578-1laxp18.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=314&fit=crop&dpr=1 754w, https://images.theconversation.com/files/71387/original/image-20150208-28578-1laxp18.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=314&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/71387/original/image-20150208-28578-1laxp18.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=314&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Cat activity times (blue line) compared with spotlight survey times (grey shading). Cats were more nocturnal in north east Tasmania (early DFTD region, where DFTD arrived 1996-1999) and would likely be more detectable in spotlight surveys than in the mid DFTD region (DFTD arrived 2000-2003).</span>
<span class="attribution"><span class="source">Bronwyn Fancourt</span></span>
</figcaption>
</figure>
<h2>Are cats to blame for quoll declines?</h2>
<p>Eastern quolls have declined by <a href="http://www.publish.csiro.au/?paper=AM13004">more than 50%</a> over the 10 years to 2009 with no sign of recovery. Our research investigated whether this decline might have been linked with changes in cat populations following devil declines. </p>
<p>Contrary to predictions, we found no evidence that cats contributed to the recent quoll decline. But our findings suggest that cats might be preventing populations from recovering by killing young quolls.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/71392/original/image-20150208-28612-1o65o8v.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/71392/original/image-20150208-28612-1o65o8v.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/71392/original/image-20150208-28612-1o65o8v.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/71392/original/image-20150208-28612-1o65o8v.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/71392/original/image-20150208-28612-1o65o8v.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/71392/original/image-20150208-28612-1o65o8v.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/71392/original/image-20150208-28612-1o65o8v.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/71392/original/image-20150208-28612-1o65o8v.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Eastern quoll declines do not appear to be caused by any increase in feral cats.</span>
<span class="attribution"><span class="source">Bronwyn Fancourt</span></span>
</figcaption>
</figure>
<p>At a stable quoll site on Bruny Island, the number of quolls trapped predictably increased over summer as new young quolls emerged - an annual cycle that has been observed historically in stable quoll populations. </p>
<p>However, at our three study sites where quolls had declined, this summer population spike did not occur, suggesting that juveniles are not surviving to enter the population, possibly because cats are eating them.</p>
<p>We found that cat activity changed seasonally, with daytime activity in winter but more nocturnal activity in summer – the time of year when vulnerable juvenile quolls first emerge from their dens.</p>
<p>Unfortunately, this predation intensity may increase further should cats become more nocturnal following devil decline.</p>
<h2>The outlook</h2>
<p>We have only just begun to understand how devils, cats and quolls interact in Tasmania. Extensive research is currently underway that will hopefully provide us with some much needed insights over coming years.</p>
<p>We provide a cautionary tale that highlights the need to consider alternative hypotheses to explain observed patterns, as the implications for species conservation could vary dramatically. </p>
<p>Bold decisions and novel approaches are required to stem the rising tide of <a href="https://theconversation.com/to-save-australias-mammals-we-need-a-change-of-heart-27423">Australian mammal extinctions</a>. Proposals to reintroduce devils to the mainland are commendable and may potentially yield benefits for species conservation.</p>
<p>However, our findings from Tasmania suggest that the predicted benefits of such reintroductions may not be so predictable.</p><img src="https://counter.theconversation.com/content/37151/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bronwyn Fancourt does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.</span></em></p><p class="fine-print"><em><span>Elissa Cameron receives funding from the Australian Research Council.</span></em></p>Proposals to reintroduce Tassie devils to the Australian mainland have argued devils could help control feral cats. But new research shows there’s no simple answer.Bronwyn Fancourt, PhD candidate in Wildlife Ecology, University of TasmaniaElissa Cameron, Professor of Wildlife Ecology, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/358552015-01-07T19:27:23Z2015-01-07T19:27:23ZShip Australia’s wildlife out to sea to save it from extinction<p>Australia is in the grip of <a href="https://theconversation.com/to-save-australias-mammals-we-need-a-change-of-heart-27423">an extinction crisis</a>. Our unique animals, plants, and ecosystems are rapidly ebbing away in a process that began more than 200 years ago with European settlement. Feral cats and foxes are thought to be major culprits. </p>
<p>So how do we stem the flood of extinctions? Predator-free offshore islands, previously seen as a last resort, could be a significant part of Australia’s conservation future. Other countries, such as New Zealand, can show us how it’s done. </p>
<p>In 2014 Australia appointed its first <a href="http://www.environment.gov.au/biodiversity/threatened/commissioner">Threatened Species Commissioner</a>, Gregory Andrews. Andrews faces <a href="https://theconversation.com/threatened-species-win-a-voice-in-canberra-but-its-too-late-for-some-28667">a huge challenge</a> in saving Australia’s endangered animals and plants, but islands should be part of the solution. </p>
<p>Mammals have been particularly hard hit by the extinction crisis, with around 10% of Australian species extinct and a <a href="http://www.publish.csiro.au/paper/ZO08027.htm">further 20% under threat</a>. Globally this accounts for <a href="http://onlinelibrary.wiley.com/doi/10.1111/geb.12088/abstract">almost a third</a> of all recent mammal extinctions. </p>
<p>There is increasing scientific consensus that cats and foxes are a powerful driver of these extinctions, amplified by land clearing and frequent, large-scale bushfires that <a href="http://onlinelibrary.wiley.com/doi/10.1111/geb.12088/abstract">degrade and fragment wildlife habitat</a>.</p>
<h2>Island woes</h2>
<p>The impact of introduced predators is not surprising considering that Australia is an island continent whose wildlife has been isolated from the rest of the world for millions of years. </p>
<p>A similar fate has befallen unique wildlife on other isolated islands, a notorious case being the impact of introduced predators on New Zealand’s <a href="http://environmentalhistory-au-nz.org/2014/11/review-island-reserves-and-mainland-islands-including-a-review-of-ecosanctuaries/">birds</a>. Thirteen are extinct and a further 24 are endangered including kiwis and the kakapo, the world’s largest parrot.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/9T1vfsHYiKY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Stephen Fry has an encounter with an endangered kakapo.</span></figcaption>
</figure>
<p>The conservation response has followed very different pathways in Australia and New Zealand. </p>
<p>New Zealand is a world leader in the use of offshore islands and fenced sanctuaries to conserve species threatened by predators. It has well-developed policies and monitoring programs for translocating endangered species by both government and <a href="http://notornis.osnz.org.nz/system/files/Cromarty%20%26%20Alderson%202013.pdf">non-government conservation programs</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/68163/original/image-20150105-8451-yp33kb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/68163/original/image-20150105-8451-yp33kb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/68163/original/image-20150105-8451-yp33kb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/68163/original/image-20150105-8451-yp33kb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/68163/original/image-20150105-8451-yp33kb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/68163/original/image-20150105-8451-yp33kb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/68163/original/image-20150105-8451-yp33kb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/68163/original/image-20150105-8451-yp33kb.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">New Zealand’s threatend birds, such as this takahe, have found a new home on offshore islands.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/sondyaustin/3239897012">Sandy Austin/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<p>By contrast, Australia’s use of island refuges has been much slower and poorly coordinated, and unlike New Zealand there is <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1442-9993.2011.02264.x/abstract">no national policy framework</a>. Approaches vary widely between Australian states, and there has been limited evaluation of what has and has not worked nationally. However, we know that the absence of cats and foxes is a critical factor in <a href="http://onlinelibrary.wiley.com/doi/10.1111/mam.12020/abstract">successfully moving wildlife to islands</a>. </p>
<p>Constructing predator-proof fences has been successful in conserving mammals, although this a fairly recent development led by a number of non-government conservation organisations such as <a href="http://www.aridrecovery.org.au">Arid Recovery Centre</a> and <a href="http://www.australianwildlife.org">Australian Wildlife Conservancy</a>.</p>
<h2>How many islands?</h2>
<p>Remarkably there has been no systematic analysis of the potential to use Australian offshore islands as conservation refuges. </p>
<p>Our preliminary analysis suggest that currently Australia has around 200 cat and fox-free islands suitable for wildlife refuges. This number could be increased if cats and foxes are removed from other islands.</p>
<p>However, because there are few offshore islands with arid climates, we will still need fenced enclosures to conserve Australia’s inland mammals.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/68155/original/image-20150105-8439-1u8i5fm.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/68155/original/image-20150105-8439-1u8i5fm.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/68155/original/image-20150105-8439-1u8i5fm.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=417&fit=crop&dpr=1 600w, https://images.theconversation.com/files/68155/original/image-20150105-8439-1u8i5fm.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=417&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/68155/original/image-20150105-8439-1u8i5fm.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=417&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/68155/original/image-20150105-8439-1u8i5fm.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=524&fit=crop&dpr=1 754w, https://images.theconversation.com/files/68155/original/image-20150105-8439-1u8i5fm.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=524&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/68155/original/image-20150105-8439-1u8i5fm.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=524&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 number of potential wildlfie refuge islands in Australia broken down by State/Territory and climate zones. Candidate islands were selected if they were: (i) fox and cat free (ii) between 1 and 10000 km square (iii) had at least 50% native vegetative cover (iv) were more than 1 km from the mainland and (v) were not within a World Heritage Area. Note the limited number with arid climates. Based on DEWHA, feral animals on offshore islands database 2010.</span>
<span class="attribution"><span class="source">Áine Nicholson, David Bowman and Grant Williamson</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Creating mini-zoos?</h2>
<p>The barriers to widespread use of offshore islands and exclosures are ultimately philosophical. A common criticism is that keeping animals on islands or behind fortified fences is “unnatural” and is akin to creating “<a href="http://newzealandecology.org/nzje/2997.pdf">mini zoos</a>”.</p>
<p>But on a continent where the ecology has been so drastically upset by introduced species, debates about “naturalness” are a distraction from the pressing threat of extinction. </p>
<p>There are also concerns that moving wildlife can have disruptive effects on other species or ecosystems. </p>
<p>For instance, moving Tasmanian Devils, threatened with the contagious <a href="https://theconversation.com/tassie-devil-facial-tumour-is-a-transmissible-cancer-34312">devil facial tumour disease</a>, to Maria Island has been criticised because of the <a href="http://www.abc.net.au/news/2014-11-28/bid-to-save-birds-from-tasmania-devils-on-maria-island-haven/5926934">potential threat to local birds</a>. </p>
<p>However, most offshore islands have already been impacted by land clearing and the introduction of domestic and native species. For instance, <a href="http://www.parks.tas.gov.au/index.aspx?base=24479">on Maria Island</a> areas of former farmland now support introduced Cape Barren Geese and large kangaroo and wallaby populations introduced by wildlife managers in the 1960s.</p>
<p>There is no question Australia’s worsening extinction crisis is motivating a rethink of classical conservation practises. </p>
<p>For example, in Kakadu National Park there are plans to move some endangered wildlife species to <a href="http://www.abc.net.au/news/2014-11-03/plan-to-help-kakadu-threatened-species/5862558">the park’s only island</a> and establish <a href="http://www.nerpnorthern.edu.au/sites/default/files/managed/files/kakadu_strategy_-_31-10-14.pdf">predator-proof exclosures</a>. </p>
<p>Such interventions could be scaled up nationally, a program that would require leadership, decisive action and risk taking in the face of looming defeat.</p><img src="https://counter.theconversation.com/content/35855/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Bowman receives funding from NERP, TERN and ARC research funding programs.</span></em></p><p class="fine-print"><em><span>Áine Nicholson 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>Australia is in the grip of an extinction crisis. Our unique animals, plants, and ecosystems are rapidly ebbing away in a process that began more than 200 years ago with European settlement. Feral cats…David Bowman, Professor, Environmental Change Biology, University of TasmaniaÁine Nicholson, Student, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/343122014-11-18T19:24:18Z2014-11-18T19:24:18ZTassie devil facial tumour is a transmissible cancer<figure><img src="https://images.theconversation.com/files/64811/original/y4n3bm4t-1416288722.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tassie devils in the wild are prone to the transmissible cancer.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/wodjamiff/8134040214">Flickr/roger smith</a></span></figcaption></figure><p>On Monday this week The Conversation published a story under the headline “<a href="https://theconversation.com/whats-killing-tassie-devils-if-it-isnt-a-contagious-cancer-32318">What’s killing Tassie devils if it isn’t contagious cancer?</a>” The article suggested evidence that the Tasmanian devil facial tumour disease (DFTD) is a transmissible cancer is inconclusive and instead, environmental chemicals could be to blame. This misrepresents the state of the science.</p>
<p>All the latest research points to the fact that the deadly DFTD is <a href="http://www.ncbi.nlm.nih.gov/pubmed/22341448">a transmissible cancer</a> that originated in a female Tasmanian devil. A single cell in this devil (patient zero) developed into a cancer cell.</p>
<p>This is nothing unusual as cancers, whether they are devil or human, originate from a single cell. This single cell divided uncontrollably to produce a tumour (mass of cells).</p>
<p>DFTD developed mechanisms to avoid being killed by the devil’s immune system. Again, nothing unusual – cancer cells usually develop such strategies.</p>
<p>What is unusual about DFTD, though, is that it is transmitted between devils. The same cancer cells from patient zero have spread throughout most of the Tasmanian devil population, killing every devil infected.</p>
<h2>The disease spreads</h2>
<p>The first case was identified in the far north-east of Tasmania in 1996. Trapping trips instigated by the government’s Save the Tasmanian Devil Program and the University of Tasmania have monitored the disease as it <a href="http://www.sciencedirect.com/science/article/pii/S0006320706001595">spread south and west</a> throughout Tasmania.</p>
<p>Each year DFTD has spread further. This pattern of spread is consistent with an infectious disease, rather than a disease caused by carcinogens present throughout the state. The far north-west of Tasmania remains disease-free.</p>
<p>Several independent lines of evidence support that DFTD originated as a single clone, from DFTD cells in patient zero. A study <a href="http://www.nature.com/nature/journal/v439/n7076/abs/439549a.html#close">published in Nature</a> in 2006 proposed devil-to-devil transmission of the cancer cells and the clonal origin of DFTD, based on chromosomal analysis.</p>
<p>More <a href="http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1002483">recent studies</a> (including <a href="http://www.ncbi.nlm.nih.gov/pubmed/22341448">here</a> and <a href="http://www.ncbi.nlm.nih.gov/pubmed/22469509">here</a>) have indicated that all tumours share similar complex chromosomal rearrangement.</p>
<h2>The tumours alike</h2>
<p>The DNA sequencing work of the UK’s <a href="http://www.ncbi.nlm.nih.gov/pubmed/20044575">Elizabeth Murchison</a> showed that the DNA of the cancer cells and the host devil are different. All DFTD tumours share the same or very similar genotypes at microsatellite loci, a small section of DNA that you can sequence.</p>
<p>They are also genetically distinct from their host. The difference is so large that DFTD could not have developed from each host.</p>
<p>Add to this <a href="http://www.ncbi.nlm.nih.gov/pubmed/22341448">whole genome analysis</a>, which indicates that all DFTDs <a href="http://www.pnas.org/content/108/30/12348.short">share point variants</a>, structural variants and copy number changes, which are distinct from their hosts.</p>
<p>All of this research highlights that the karyotype and genotype are consistent between DFTD tumours and distinct from that of their hosts and supports the transmissible nature of the tumour.</p>
<p>A transmissible tumour requires a particular behaviour to allow the transfer of cells between individuals, as well as mechanisms to escape the immune response. DFTD was named facial tumour disease, because this is where tumours are found.</p>
<p>It is a <a href="http://www.ncbi.nlm.nih.gov/pubmed/20044575">cancer of Schwann cells</a> which are cells that wrap around peripheral nerves. The face is rich in peripheral nerves and provides an excellent environment for Schwann cell growth. </p>
<h2>Transmission in the bite</h2>
<p>Devil biting behaviour accounts for the transmission. Devils typically bite each other on the face and neck and the bites penetrate and cause substantial wounds. DFTD cells have been <a href="http://tasmaniantimes.com/images/uploads/obendorf_eur_j_oncol_4-08.pdf">identified on the teeth</a> of diseased devils and the penetrating bites can transfer DFTD cells.</p>
<p>The transfer of DFTD cells occurs when diseased <a href="http://www.ncbi.nlm.nih.gov/pubmed/22943286">devils bite healthy devils</a> or when healthy devils bite diseased devils and tumour cells become incorporated into the oral cavity, establishing DFTD inside the mouth.</p>
<p>The biting and location of DFTD growth accounts for the transmission, but the “transplanted” tumour cells must then escape the host devil’s immune response to avoid rejection as a “foreign graft”. A <a href="http://www.pnas.org/content/104/41/16221.abstract">proposal to account for this</a> was that devils lack genetic diversity and are not recognised as “foreign” by the host devil’s immune system.</p>
<p>Based on genome sequencing Tasmanian devils do have a <a href="http://www.pnas.org/content/108/30/12348.short">reduced genetic diversity</a>. But the low genetic diversity does not account for the lack of graft recognition as skin grafts between devils are <a href="http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0022402">immunologically rejected</a>.</p>
<p>Although reduced genetic diversity may contribute to successful tumour transmission, further research was required to explain the mechanisms of immune escape. This research has been completed, but was not included in <a href="https://theconversation.com/whats-killing-tassie-devils-if-it-isnt-a-contagious-cancer-32318">Monday’s article</a>. </p>
<h2>A breakthrough</h2>
<p>Recent <a href="http://www.pnas.org/content/110/13/5103">breakthrough research</a> has identified the main reason that DFTD cells are not immunologically rejected. The tumour cells do not express major histocompatibility (MHC) antigens on their cell surface.</p>
<p>These are immune recognition molecules and without them the cells are “invisible” to the devil’s immune system. This is an effective strategy used by the transmissible tumour found in dogs, the canine transmissible venereal tumour (CTVT). This tumour has existed for centuries and the cancer cells are sexually transmitted. CTVT avoids immune recognition in the new host because the tumour cells do not express MHC molecules.</p>
<p>The pattern of DFTD distribution and spread also supports the transmissible nature of the tumour. If environmental carcinogens were causing DFTD, there should be random occurrences of DFTD throughout the state.</p>
<p>This has not been seen, and instead the disease is spreading across the state in a manner consistent with a contagious disease. All the scientific evidence points to DFTD as a transmissible cancer, rather than a carcinogen-induced cancer. </p>
<p>To save this iconic species, only found in Tasmania, the Save the Tasmanian Devil Program established an insurance population. This has been a major undertaking that has relied on the goodwill of many wildlife parks and zoos around Australia.</p>
<h2>Safe in captivity</h2>
<p>The devil is now safe from extinction, at least in captivity. The next challenge is to protect Tasmanian devils in the wild.</p>
<p>To this end much research effort needs to be directed towards a vaccine. This is the goal of my research group. We have been diligently analysing the devils’ <a href="http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0024475">immune system</a>. This research points to the devil having a <a href="http://link.springer.com/article/10.1007%2Fs10393-007-0117-1">competent immune system</a>.</p>
<p>The Achilles heel of DFTD is that the genes for MHC are present, but turned off. We have discovered the “switch” to <a href="http://www.pnas.org/content/110/13/5103">turn these genes on</a> and this forms the basis for our vaccine research.</p>
<p>We may never know what caused DFTD in patient zero. It was most likely an accident of nature. Carcinogens may have played a role.</p>
<p>Although it would be of scientific interest to know the answer and undertake a large and expensive survey, the most important challenge is to save the devils in the wild. This is one of the major aims of the Save the Tasmanian Devil Program.</p>
<p>The past is history and the present learns from the past to inform the future. Habitat destruction does add extra stresses on our native wildlife and the future must take this into account.</p>
<p>The immediate task for us is to pursue vaccine development with the aim of protecting the healthy devils and repopulating the state with devils that have resistance to DFTD.</p><img src="https://counter.theconversation.com/content/34312/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Greg Woods receives funding from Australian Research Council and Save the Tasmanian Devil Appeal.</span></em></p>On Monday this week The Conversation published a story under the headline “What’s killing Tassie devils if it isn’t contagious cancer?” The article suggested evidence that the Tasmanian devil facial tumour…Greg Woods, Professional Research Fellow, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/323182014-11-16T19:15:43Z2014-11-16T19:15:43ZWhat’s killing Tassie devils if it isn’t a contagious cancer?<figure><img src="https://images.theconversation.com/files/64543/original/wyywsbhv-1415934017.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Is the dying Tassie devil the victim of some undone science?</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/17251154@N00/14587946949">Flickr/Sy</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/">CC BY-NC-SA</a></span></figcaption></figure><p><em>Editors note: The argument in the following piece has been refuted in a seperate article titled <a href="https://theconversation.com/tassie-devil-facial-tumour-is-a-transmissible-cancer-34312">Tassie devil facial tumour is a transmissible cancer</a>.</em></p>
<p>Scientists have been trying to figure out the cause of the deadly cancer affecting so many Tasmanian devils but the research doesn’t seem to be providing many useful answers. What if they’re looking in the wrong place for a cause and a cure?</p>
<p>The <a href="http://australianmuseum.net.au/Tasmanian-Devil">Tasmanian devil</a> is Australia’s largest carnivorous marsupial. It is currently listed as “endangered” and risks becoming extinct. Most of the devils in Tasmania are developing ugly tumours on their faces due to what is called devil facial tumour disease (<a href="http://www.tassiedevil.com.au/tasdevil.nsf/TheDisease/979FEB5F116CE371CA2576CB0011A26E">DFTD</a>), and it is nearly always fatal.</p>
<p>The disease was first observed in 1996 and research into it began in 2003.</p>
<p>In 2006, two Tasmanian government researchers, Anne-Marie Pearse and Kate Swift, published a <a href="http://news.bbc.co.uk/2/hi/science/nature/4674446.stm">short article</a> in the scientific journal Nature suggesting that the devil disease was a contagious cancer spread from one devil to another by biting. This hypothesis became the basis for much subsequent research.</p>
<p>It was a bold and unorthodox theory, especially considering that there are only a handful of contagious wildlife cancers around the world. Furthermore, the pathway of spread by biting would be unique worldwide. </p>
<h2>Theory doesn’t bite</h2>
<p>It is true that Tasmanian devils <a href="http://www.publish.csiro.au/pid/2550.htm">bite each other</a> in ritual fights, but their teeth are not sharp and not an obvious mechanism for spreading cancer. Furthermore, various complications soon emerged from the biological research.</p>
<p>To spread from one devil to another, the genetics of the devils have to be similar so rejection of the foreign cells does not occur. It was proposed that devils had limited genetic variability, but later this turned out <a href="http://www.abc.net.au/worldtoday/content/2012/s3523185.htm">to be incorrect</a>. There are not even any studies that conclusively show that the devil cancer is transmissible from one animal to another.</p>
<p>Eventually the research seemed to reach a dead end, with too many contradictions. Meanwhile, devils kept dying.</p>
<p>There is <a href="http://media.wix.com/ugd/d053d8_1d3102909bdc4adb99a72eec5b99da8b.pdf">another possible explanation</a> for the devil disease, either its origin or its spread or both: environmental chemicals.</p>
<h2>Look to the trees</h2>
<p>In Tasmania, huge areas are taken up by <a href="http://www.fpa.tas.gov.au/__data/assets/pdf_file/0009/82872/State_of_the_forests_Tasmania_2012_report.pdf">plantation forests</a>, and these are regularly sprayed with pesticides and poisons.</p>
<p>Of special concern is the pesticide <a href="http://archive.apvma.gov.au/news_media/chemicals/atrazine.php">atrazine</a>, used to control grass and broadleaf weeds. The Australian Pesticides and Veterinary Medicines Authority carried out an <a href="http://apvma.gov.au/node/1416">extensive review</a> and considers atrazine safe to use under <a href="http://archive.apvma.gov.au/news_media/chemicals/atrazine.php">current guidelines</a> which include “conditions outlined on product labels”. The Tasmanian government’s <a href="http://dpipwe.tas.gov.au/Documents/Information%20Sheet%20-%20Atrazine_Jan2014.pdf">information on atrazine</a> says it “does not cause mutations” and is “not likely to cause cancer”.</p>
<p>But there are those who <a href="http://www.atrazinelovers.com/m7.html">point to research</a> that suggests atrazine is a cancer promoter. The US Environmental Protection Agency had <a href="http://www.epa.gov/oppsrrd1/reregistration/atrazine/atrazine_update.htm">this to say</a> following its review of studies by a federal Scientific Advisory Panel:</p>
<blockquote>
<p>Even though the panel agreed with EPA that the epidemiologic evidence does not strongly suggest a link between atrazine and cancer, the panel did not agree that a lack of strong evidence justifies a conclusion that atrazine is not likely to be a human carcinogen.</p>
</blockquote>
<p>Also of concern is the poison <a href="http://dpipwe.tas.gov.au/agriculture/agvet-chemicals/1080-poison">1080</a>, used to kill native species that are a key part of the devil diet. The Tasmanian government says devils have a relatively high tolerance to the poison but it also concedes there is a risk of secondary poisoning with three poisoned pademelons likely to be fatal to a 5kg devil.</p>
<p>Plantation forestry pesticides contaminate <a href="http://tasmaniantimes.com/index.php/article/clean-water-needs-revised-forestry-operations">44 of 48</a> river catchments in Tasmania.</p>
<p>So a role for pesticides and poisons seems plausible, because the devil disease is found only in parts of Tasmania where there are extensive forest plantations. Furthermore, because devils, as carnivores, are at the top of the food chain, toxic chemicals in the environment are concentrated in their diet. </p>
<h2>We need more studies</h2>
<p>Early in the devil cancer story, some scientists <a href="http://www.tassiedevil.com.au/tasdevil.nsf/TheDisease/01E084030D8DE533CA2576D200176CC3">called for studies</a> of the presence of toxic chemicals to be carried out. But this was not followed up at the time.</p>
<p>For some reason, the contagious-cancer hypothesis received the majority of funding and attention. There was eventually a limited pilot <a href="http://tasmaniantimes.com/index.php/article/devil-of-a-cocktail">toxicology study</a>, the reviewers of which called for further investigations, but there have been none. </p>
<p>A toxic-chemical cause is even more plausible considering the <a href="http://jodeswarren.wix.com/devilsadvocate">other three species</a> about which claims have been made of a viral contagious cancer: Beluga whales in Canada, California sea lions in the US and green sea turtles in several countries including Australia. Each of these species is exposed to environmental chemicals, including atrazine, but again toxicological studies have not been carried out.</p>
<p>Environmentalists in Tasmania have fought courageous battles to protect native forests. But in the past decade there has been little public criticism of plantation forestry and the associated impacts on wildlife, perhaps because the plantations allow remaining native forests to be untouched. </p>
<p>There are political advantages to the forest industry and the government in ignoring the environmental-chemical hypothesis. When political and economic influences lead to research areas being neglected, these areas are called “<a href="http://davidjhess.net/uploads/3/5/1/3/3513369/socinquiry.2009.draft.pdf">undone science</a>”. </p>
<p>There are many examples of undone science around the world, especially in the environmental area. Citizen campaigners call for certain topics to be investigated, but governments and corporations ignore or neglect them, and sometimes try to <a href="http://www.bmartin.cc/pubs/99rsppp.html">censor relevant research</a> that is done.</p>
<p>This is not a criticism of individual researchers, who do their investigations as well as they can. But a restricted availability of funds and focus of attention can lead to the <a href="http://mitpress.mit.edu/books/alternative-pathways-science-and-industry">trajectory of research</a> in a field being pushed in particular directions, especially ones convenient to the forest and chemical industries and their government patrons.</p>
<p>Meanwhile, the Tasmanian devil is dying out.</p>
<p>Valiant efforts are being made to <a href="http://www.devilark.com.au/home">preserve the species</a> by removing individual animals from Tasmania to other states and countries where they and their offspring are presumed safe from the perceived threats in their natural environment in Tasmania. This is a rear-guard operation that may distract attention from examining alternative explanations for the disease. </p>
<hr>
<p>See also: <a href="https://theconversation.com/tassie-devil-facial-tumour-is-a-transmissible-cancer-34312">Tassie devil facial tumour is a transmissible cancer</a></p><img src="https://counter.theconversation.com/content/32318/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>Editors note: The argument in the following piece has been refuted in a seperate article titled Tassie devil facial tumour is a transmissible cancer. Scientists have been trying to figure out the cause…Jody Warren, Honorary Postdoctoral Research Associate, University of WollongongBrian Martin, Professor of Social Sciences, University of WollongongLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/337882014-11-05T02:43:33Z2014-11-05T02:43:33ZTasmanian devils survived two big falls in numbers but now need help<figure><img src="https://images.theconversation.com/files/63611/original/pjrys592-1415100878.jpg?ixlib=rb-1.1.0&rect=0%2C321%2C2982%2C2316&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Tasmanian devil was once found beyond Tasmania.</span> <span class="attribution"><span class="source">Sarah Peck</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Most people probably know the <a href="https://theconversation.com/au/topics/tasmanian-devil">Tasmanian devil</a> as the iconic animal from Australia’s island state of Tasmania. Fewer know that, up until a few thousand years ago, devils were widespread across mainland Australia.</p>
<p>But something happened during the past 10,000 years and devils disappeared from the mainland, leaving behind only bones in caves from the south-west of Western Australia, across the Nullarbor, to Victoria and New South Wales. It is unclear exactly when or why they disappeared. Changes in climate, hunting by humans or the introduction of the dingo have all been proposed as likely candidates.</p>
<p>In contrast, devils survived in Tasmania, apparently in healthy numbers at the time of European arrival.</p>
<p>Like many island species, devils appear to have been saved from total extinction by being marooned on the island of Tasmania. There, they were cut off from any influence by dingos and possibly buffered against the effects of climate change. </p>
<h2>The deadly facial cancer</h2>
<p>The Tasmanian devil made headlines in 1996 when animals with large facial tumours were found at Mt William in the north-east corner of the island state. The disease, aptly named Devil Facial Tumour Disease (<a href="http://www.tassiedevil.com.au/tasdevil.nsf/folder/_thedisease">DFTD</a>), is unique in that it is transferred as live tumour cells between individuals and is consistently fatal.</p>
<p>In less than two decades DFTD has spread to the majority of the devils’ geographic range, causing more than 80% population declines. Today, devils are once again threatened with total extinction.</p>
<p>Large-scale efforts are underway to protect devil populations in the wild and to establish insurance populations in zoos and on offshore islands, free of the disease.</p>
<p>In the past ten years Tasmanian devil <a href="http://www.tassiedevil.com.au/tasdevil.nsf/Research-News/7383F27726ECB08ACA2576D20003AEF5">research</a> has rightly focused on the origin, spread and impacts of DFTD on devil populations.</p>
<p>A major outcome of this research has highlighted the unusually low genetic diversity in Tasmanian devil populations – a feature at odds with their large pre-DFTD population size.</p>
<p>This low diversity is a major extinction risk factor in itself but may also have contributed to the rapid spread of DFTD from its origin at Mt William. Climatic or environmental effects may have caused low genetic diversity long before Europeans arrived in Tasmania.</p>
<p>Alternatively, genetic declines may have occurred rapidly in the past 200 years as a result of land clearing, introduced disease or hunting.</p>
<h2>Why the low diversity?</h2>
<p>In a paper published today in the journal <a href="http://dx.doi.org/10.1098/rsbl.2014.0619">Biology Letters</a>, we used a large genetic data-set from more than 300 modern and historical devils to reconstruct changes in past population size. The aim was to understand what may have caused population declines and loss of genetic diversity. </p>
<p>Using DNA from Tasmanian devils sampled in 2004–2005 from nine sites across the island, and samples from 1964 from Mt William, we used new statistical methods to estimate past and current population sizes and piece together the history of devils in Tasmania.</p>
<p>Our results show that Tasmanian devils have suffered (but survived) two major population declines and have had a low genetic diversity for thousands of years.</p>
<p>These declines occurred before 20,000 years ago, corresponding to the last glacial maximum, and around 2,000 to 4,000 years ago, about the time of an increase in El Niño–Southern Oscillation activity.</p>
<h2>Limited prey</h2>
<p>Both climatic events resulted in a much drier climate. These more arid conditions may have resulted in changes in vegetation, influenced prey abundance and altered den site availability – with negative impacts on devil population size.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/63673/original/r8cc8rc7-1415150213.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/63673/original/r8cc8rc7-1415150213.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/63673/original/r8cc8rc7-1415150213.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=441&fit=crop&dpr=1 600w, https://images.theconversation.com/files/63673/original/r8cc8rc7-1415150213.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=441&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/63673/original/r8cc8rc7-1415150213.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=441&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/63673/original/r8cc8rc7-1415150213.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=554&fit=crop&dpr=1 754w, https://images.theconversation.com/files/63673/original/r8cc8rc7-1415150213.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=554&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/63673/original/r8cc8rc7-1415150213.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=554&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Tasmanian devils are a top predator.</span>
<span class="attribution"><span class="source">Sarah Peck</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>As a top predator, devil population density is known to be largely driven by prey abundance, so a decline in wallaby and small mammal numbers would have had a dramatic effect on devil population size. </p>
<p>Our research shows that devils did not lose genetic diversity rapidly in the past 200 years as a result of human activities or as the result of DFTD. Rather they have survived for thousands of years with low genetic diversity as the result of environmental change.</p>
<p>The low genetic diversity is a major extinction threat to the species. Devils highlight the precarious state of many species whose numbers appear to be secure.</p>
<p>The arrival of any new disease or rapid changes in the environment can have dramatic and disastrous effects. The combined effects of DFTD and predicted climate changes make it imperative that conservation measures are taken to assure the survival of the Tasmanian devil in the wild.</p>
<p>Trapped on the island of Tasmania, devils have survived two major population declines in the past, but will they endure these current threats?</p><img src="https://counter.theconversation.com/content/33788/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anna Brüniche-Olsen receives funding from Australian Postgraduate Award Industry (APAI) scholarship, the Save the Tasmanian Devil Program, Holsworth Wildlife Research Endowment, Winifred Violet Scott Charitable Trust, School of Zoology at the University of Tasmania, Society of Molecular Biology and Evolution (SMBE), the Royal Zoological Society of New South Wales (RZS NSW) and the Ecological Society of Australia (ESA).
The National Climate Change and Adaptation Research Foundation (NCCARF).</span></em></p><p class="fine-print"><em><span>Jeremy Austin receives funding from the Australian Research Council, Zoos SA, and the Save the Tasmanian Devil Program.</span></em></p>Most people probably know the Tasmanian devil as the iconic animal from Australia’s island state of Tasmania. Fewer know that, up until a few thousand years ago, devils were widespread across mainland…Anna Brüniche-Olsen, University of TasmaniaJeremy Austin, Deputy Director and ARC Future Fellow, Australian Centre for Ancient DNA, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/233612014-02-26T19:23:42Z2014-02-26T19:23:42ZAustralia’s environment minister could soon be above the law<figure><img src="https://images.theconversation.com/files/42563/original/8g9wxm5t-1393401202.jpg?ixlib=rb-1.1.0&rect=8%2C8%2C2991%2C1994&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Greg Hunt, and all environment ministers past and future, could be protected from legal challenge over mining approvals.</span> <span class="attribution"><span class="source">AAP Image/Alan Porritt</span></span></figcaption></figure><p>Earlier this month, a Senate inquiry paved the way for the Parliament to give Environment Minister Greg Hunt <a href="http://www.smh.com.au/federal-politics/political-news/tony-abbott-legalchallenge-bill-a-risk-to-rule-of-law-20140213-32n90.html">legal immunity</a> against future legal challenges to his decisions on mining projects.</p>
<p>If it passes the Senate, the move will protect the government from being taken to court over the <a href="https://theconversation.com/australia-courting-danger-with-the-great-barrier-reef-20411">Abbot Point dredging scheme</a>, the <a href="http://www.bechtel.com/curtisisland_lng.html">Curtis Island gas project</a>, or any other environmentally contentious development in Australia.</p>
<p>More extraordinary is the fact that the government (with Labor’s help) has pushed the legislation through to safeguard an earlier blunder made by former Labor environment minister Tony Burke. Why? Because it will protect Greg Hunt from being challenged over deliberate or negligent decisions that do not comply with the law.</p>
<h2>Trouble in Tasmania</h2>
<p>In 2012, Burke approved a proposal by <a href="http://www.shreeminerals.com/Scripts/default.asp">Shree Minerals</a> to develop an iron ore mine in the Tarkine area of Tasmania. The <a href="http://tarkine.org/">Tarkine National Coalition</a>, a local conservation group, took him to the Federal Court.</p>
<p>Three years earlier, the previous environment minister Peter Garrett had approved official conservation advice under the <a href="http://www.environment.gov.au/topics/about-us/legislation/environment-protection-and-biodiversity-conservation-act-1999">Environmental Protection and Biodiversity Conservation (EPBC) Act</a>, which set out threats to the endangered Tasmanian devil. </p>
<p>But Burke did not take this advice into account when approving the mine, which is in an area that is home to one of the few remaining Tasmanian devil populations not affected by the presently incurable <a href="http://www.dpiw.tas.gov.au/inter.nsf/WebPages/LBUN-5QF86G?open">devil facial tumour disease</a>.</p>
<p>In 2013, the Federal Court ruled that Burke had <a href="http://www.abc.net.au/news/2013-07-17/court-decides-tarkine-mine27s-fate/4825230">failed to comply with the EPBC Act</a>, which requires the minister to consider conservation advice provided under the Act.</p>
<p>The Coalition government has now licensed Greg Hunt (and retrospectively Tony Burke) to avoid compliance with the EPBC Act by passing the <a href="http://www.aph.gov.au/Parliamentary_Business/Bills_Legislation/Bills_Search_Results/Result?bId=r5128">Environment Legislation Amendment Act 2013</a> in direct response to the Court’s ruling against Burke.</p>
<p>The amendment retrospectively validates ministerial decisions – even if they did not comply with the EPBC Act when they were made.</p>
<h2>Breach of legal principle</h2>
<p>The problem with this approach is that it breaches internationally accepted <a href="http://www.lawcouncil.asn.au/lawcouncil/index.php/divisions/international-division/rule-of-law">legal principles</a>, for no real reason other than to assuage misplaced nervousness in the mining industry following the Court’s decision. </p>
<p>Hunt says the amendment will provide certainty for mining companies that face repeated legal challenges to previously approved projects. </p>
<p>But there was no reason to pass retrospective laws following the Tarkine decision, because Burke granted a new, valid approval straight afterwards, this time making sure he took into account the conservation advice.</p>
<p>Burke’s decision did not need to be validated retrospectively. The court didn’t order him to reject the mine; it just told him to follow the environmental rules.</p>
<h2>Legislative overkill</h2>
<p>That’s why the new amendment is overkill. Not only does it validate an unspecified number of past decisions, but it will also apply to any future decisions that do not comply with the EPBC Act. </p>
<p>The new law might have been inspired by Burke’s tribulations in the Tarkine, but its impact will reach much further. It will apply to any proposed development in any environmentally sensitive area, anywhere in Australia. </p>
<p>That could include the Great Barrier Reef, which is under threat from dredging at Abbot Point as the port is readied for the export of $28.4 billion in coal reserves from the [Galilee Basin](the expansion of the <a href="http://www.dsdip.qld.gov.au/infrastructure-and-planning/galilee-basin-development-strategy.html">Galilee Basin coal precinct</a>. </p>
<p>Activist group <a href="https://www.getup.org.au/">GetUp!</a>, among others, is attempting to mount a legal challenge against Hunt’s decision to allow the dumping of three million cubic metres of dredge spoil in the Great Barrier Reef Marine Park.</p>
<p>But the new amendment could protect the government from any such challenge. As such, it casts doubt on the integrity of the implementation of the EPBC Act itself.</p>
<p>Threatened species would be left effectively unprotected in the event that the environment minister either negligently or deliberately ignores approved conservation advice. Clearly this is not a good legislative outcome.</p>
<h2>Future impacts</h2>
<p>The Senate is set to debate the amendment again next month, having been advised by the Department of Environment that the new law will have only “minor” impacts in the future.</p>
<p>They will be far from minor unless the Senate heeds the <a href="http://www.lawcouncil.asn.au/lawcouncil">Law Council of Australia’s</a> advice to amend the legislation to ensure it does not cover future decisions (a recommendation backed by the Senate Environment Committee).</p>
<p>If they choose to accept this recommendation, then the only impact will be political. It will have achieved the aim of reassuring the minerals and energy lobby that the government is on its side – which appears to be the point of the entire bizarre exercise.</p><img src="https://counter.theconversation.com/content/23361/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Gregory McIntyre 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>Earlier this month, a Senate inquiry paved the way for the Parliament to give Environment Minister Greg Hunt legal immunity against future legal challenges to his decisions on mining projects. If it passes…Gregory McIntyre, Adjunct Professor, University of Notre DameLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/168762013-08-11T20:08:28Z2013-08-11T20:08:28ZTasmania’s Tarkine needs a strategic plan<figure><img src="https://images.theconversation.com/files/28958/original/9tqkjkrn-1376021915.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tarkine mines must now fund Tasmanian Devil conservation. But what about the rest of it?</span> <span class="attribution"><span class="source">Flickr/Gopal Vijayaraghavan</span></span></figcaption></figure><p>The Federal Government has now approved two mines for the Tarkine region of Tasmania, on condition that the mines fund conservation measures for Tasmanian Devils and other threatened species.</p>
<p>The approvals follow the Federal Court <a href="http://www.abc.net.au/news/2013-07-17/court-decides-tarkine-mine27s-fate/4825230">overturning</a> approval of the Shree Minerals mine last month, on the grounds that former Environment Minister Tony Burke failed to consider conservation advice on Tasmanian Devils. </p>
<p>The death of a few devils, orchids, spotted-tail quolls or wedge-tailed eagles are unlikely to have significant impacts on their populations. But what’s missing from the assessments are the cumulative effects of the many mines proposed for the region. There are currently ten mines proposed in the next five years, and over 50 exploration licenses held over the region. </p>
<p>So, how are Tasmania and the Commonwealth to account for potential cumulative impacts? </p>
<h2>More mines the merrier?</h2>
<p>In announcing Commonwealth <a href="http://www.environment.gov.au/minister/butler/2013/mr20130731.html?utm_source=mins&utm_medium=rss&utm_campaign=feed">approval</a> of the Shree Minerals mine, new environment minister Mark Butler made clear he had taken the Conservation Advice into account. </p>
<p>Shree Minerals will have to pay A$350,000 to maintain an “insurance population” of devils against <a href="https://theconversation.com/saving-the-tasmanian-devil-if-not-by-selective-culling-then-how-3714">Devil Facial Tumour Disease</a>, and a further A$48,000 for additional devils killed on roads. </p>
<p>Venture Minerals also received Commonwealth <a href="http://www.environment.gov.au/minister/butler/2013/mr20130805.html">approval</a> for a small surface mining operation near Riley Creek. This is a fundraiser for two large mines proposed elsewhere in the Tarkine. </p>
<p>Similar restrictions were imposed on roadkill. In the case of Venture Minerals, the Commonwealth relied on the Tasmanian Environmental Assessment Report to reach its decision.</p>
<p>Current state assessments only consider the way in which proposals exacerbate existing problems. They do not look at the cumulative impacts of future proposals. </p>
<p>The Tasmanian assessment report for the project devoted a mere half page to cumulative impacts, to meet Commonwealth requirements.</p>
<p>The combined impact if all ten mines were given approval could be considerable, for the devil and other endangered species, as well as the Tarkine landscape. We’re yet to see how the Commonwealth will address this risk of “death by a thousand cuts”. </p>
<h2>The role of the Commonwealth</h2>
<p>The Commonwealth has a long history of environmental intervention, dating back to the halting of <a href="http://www.naa.gov.au/Images/mining-environment_tcm16-45396.pdf">sand mining</a> on Fraser Island and the <a href="http://www.envlaw.com.au/tasmanian_dam.html">Franklin River dam</a> in Tasmania in the 1970s-80s. </p>
<p>National environmental laws have been a “<a href="https://theconversation.com/sydney-harbours-toxic-legacy-shows-value-of-green-safety-net-11197">green safety net</a>”. They are intended to ensure that state approvals do not put local economic development above nationally important environmental values. </p>
<p>But the Commonwealth’s role is limited to considering impacts on “<a href="http://www.environment.gov.au/epbc/protect/">matters of national environmental significance</a>”. These matters usually come down to world heritage areas, migratory, threatened and endangered species, and national heritage places.</p>
<p>In February this year former environment minister Tony Burke rejected listing the entire Tarkine region as a National Heritage area. In doing this he significantly constrained the Commonwealth’s role in shaping the environmental future of the Tarkine. The <a href="http://www.environment.gov.au/cgi-bin/ahdb/search.pl?mode=place_detail;place_id=105751">heritage area</a> currently includes 4% of the region along the coastal strip. It is conserved for its Aboriginal heritage values. </p>
<p>Listing the area for its natural values would not necessarily have prevented mining in the Tarkine. But it would have made Commonwealth approvals processes more costly and time-consuming, and imposed heavier conditions on approval. </p>
<p>Now, instead of requiring every new mine to address potential impacts on the wide-ranging ecological, geological and landscape values that underpin heritage values, the Commonwealth only has to focus on migratory and protected species. </p>
<p>Opposition to the mines has concentrated on the potential impacts of new mines on the <a href="http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=299">endangered</a> devils. These include habitat destruction, roadkill and the risk that an expanded road network will facilitate the incursion of devils carrying the facial tumour disease.</p>
<h2>Is it jobs over heritage?</h2>
<p>The former minister made clear that his narrow heritage listing was influenced by employment opportunities and economic activity, which mining could bring to the “poorest region in the poorest state”.</p>
<p>Mining can offer a significant economic boost to a state sorely in need of new initiatives. But without a clear plan for how many mines the region should have, in which places, and under what conditions, the current decision-making processes fall short. </p>
<p>Regional or sectoral management plans are standard for land use planning and natural resources. Without such a strategic plan for the 96% of the Tarkine that missed out on national heritage listing, conflict between conservation and economic development can only escalate. Such planning must be a priority for all levels of government before new mines are approved.</p><img src="https://counter.theconversation.com/content/16876/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jan McDonald 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>The Federal Government has now approved two mines for the Tarkine region of Tasmania, on condition that the mines fund conservation measures for Tasmanian Devils and other threatened species. The approvals…Jan McDonald, Professor of Environmental Law, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/114832013-01-14T20:02:04Z2013-01-14T20:02:04ZTarkine mines could be last straw for Tasmanian devils<figure><img src="https://images.theconversation.com/files/19014/original/k9bs57gt-1357537690.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Road traffic is a threat to Tasmania's few health devils - increased truck traffic in the Tarkine won't help.</span> <span class="attribution"><span class="source">Rhys Allen</span></span></figcaption></figure><p>Just a week before Christmas, Environment Minister Tony Burke <a href="http://www.abc.net.au/pm/content/2012/s3659573.htm">approved</a> Shree Minerals’ mine near Temma in the Tarkine region of north-west Tasmania. Perhaps he hoped the announcement would get lost in the Christmas and New Year “silly season”, because this approval is likely to be extraordinarily controversial: the mine is in an area currently <a href="https://theconversation.com/cynical-politics-condemns-our-national-heritage-27">proposed for World Heritage listing</a> and is also in the last remaining stronghold of the Tasmanian devil.</p>
<p>The Tasmanian devil is <a href="https://theconversation.com/saving-the-tasmanian-devil-if-not-by-selective-culling-then-how-3714">threatened with extinction</a> by an infectious cancer. Since its first discovery in north-eastern Tasmania in 1996, the cancer has inexorably spread westward, reducing Tasmanian devil populations by at least 80%. </p>
<p>Only the north-west remains undiseased. There are indications that the devil populations in the north-west have slightly different genetic composition from those in the remainder of Tasmania and may perhaps harbour some individuals with genotypes resistant to this lethal disease.</p>
<p>Tony Burke’s press release and his approval of 18 December explicitly recognise the threat that this mine will pose to Tasmanian devils: the developers are required to donate $350,000 to the Save the Tasmanian Devil Program Appeal to compensate for the mine’s unavoidable impact. </p>
<p>Within the limited area of the mine site itself, there will certainly be impacts on wildlife, including devils. More seriously, the ore will need to be trucked out by road for about 150km. Almost all of this distance will be through habitat of undiseased Tasmanian devils. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/19013/original/87kv2v2w-1357537608.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/19013/original/87kv2v2w-1357537608.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=894&fit=crop&dpr=1 600w, https://images.theconversation.com/files/19013/original/87kv2v2w-1357537608.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=894&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/19013/original/87kv2v2w-1357537608.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=894&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/19013/original/87kv2v2w-1357537608.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1123&fit=crop&dpr=1 754w, https://images.theconversation.com/files/19013/original/87kv2v2w-1357537608.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1123&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/19013/original/87kv2v2w-1357537608.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1123&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">North-western devils may be resistant to facial tumours.</span>
<span class="attribution"><span class="source">Greens MPs/Flickr</span></span>
</figcaption>
</figure>
<p>As scavengers, devils are particularly susceptible to being killed on roads, as they feed on the carcasses of other animals, such as possums or wallabies, which have previously been run over. As anyone who has driven in Tasmania will know, roadkill of Tasmanian Devils is not new. The problem is that its impact on the viability of the species as a whole is much greater now than it has been in the past, given that roadkill is additional to mortality imposed by facial tumour disease. This and other proposed mines will substantially increase total vehicular traffic in the remote north west of Tasmania.</p>
<p>The approval contains several conditions intended to mitigate this threat of roadkill to devils. These include an obligation to report all incidents of roadkill, a requirement that most travel to and from the mine site must occur during daylight hours and reduced speed limits of 50 km/h or less close to the mine site. But most of the distance mine trucks will travel through devil habitat on their way to port will be outside the reduced-speed-limit area. </p>
<p>A penalty of $48,000 will be applied to each Tasmanian devil in excess of two per year killed on the road by mine vehicles. This sounds a strong disincentive in principle, but I wonder what will happen in practice. There will be an even stronger incentive for vehicle operators to simply throw a carcass off the road into the bush rather than admit to killing a devil and incurring this substantial financial penalty.</p>
<p>More generally, this example highlights a problem with Australian environmental regulation. Up to 10 mine developments are currently proposed for the Tarkine area. The impact of each one individually might perhaps be acceptable in terms of increased risk of impacts on Tasmanian devil populations. But the impact of all 10 in aggregate will certainly be much less acceptable. </p>
<p>If mines are evaluated individually, we risk a scenario of “death by 1000 cuts”. The appropriate way to evaluate the risk would be to take all of the proposed developments together and assess whether the joint effect of all can be handled without unacceptable risk to biodiversity conservation. </p>
<p>The fact that this mine development has been approved individually does not give me confidence this approach will be taken.</p><img src="https://counter.theconversation.com/content/11483/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Hamish McCallum receives funding from the ARC for research on Tasmanian Devil Facial Tumour Disease. His students have previously received funding from the Save the Tasmanian Devil Program Appeal. From 2006-2009 he was the Senior Scientist of the Save the Tasmanian Devil Program</span></em></p>Just a week before Christmas, Environment Minister Tony Burke approved Shree Minerals’ mine near Temma in the Tarkine region of north-west Tasmania. Perhaps he hoped the announcement would get lost in…Hamish McCallum, Head, Griffith School of Environment, Griffith UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/111672012-12-05T01:35:30Z2012-12-05T01:35:30ZSettlers weren’t responsible for Tasmanian devil gene decline<figure><img src="https://images.theconversation.com/files/18339/original/zjmvqyrv-1354666310.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tasmanian devils have had low genetic diversity for hundreds of years.</span> <span class="attribution"><span class="source">AAP/Devil Ark/Mandy Kennedy</span></span></figcaption></figure><p>European settlers were not responsible for thinning the gene pool of the Tasmanian devil, new research has found.</p>
<p>Tasmanian devils are currently under threat due to the spread of an aggressive facial tumour, one of only three recorded types of contagious cancer. The disease spreads so readily because genetic diversity in devils’ immune systems is low. It is passed from devil to devil through biting.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/18345/original/96fxys6z-1354670247.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/18345/original/96fxys6z-1354670247.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/18345/original/96fxys6z-1354670247.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/18345/original/96fxys6z-1354670247.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/18345/original/96fxys6z-1354670247.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/18345/original/96fxys6z-1354670247.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/18345/original/96fxys6z-1354670247.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/18345/original/96fxys6z-1354670247.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">Tasmanian devils suffer a rare form of contagious cancer.</span>
<span class="attribution"><span class="source">AAP/Sarah Peck</span></span>
</figcaption>
</figure>
<p>It had previously been assumed that this lack of diversity was due to population decline that occurred as a result of European settlement.</p>
<p>“The devil population has actually undergone a few population crashes over the past 200 years, and we thought that the crashes might have caused this low immune gene diversity,” lead author Katrina Morris said.</p>
<p>But the results of the study, published in Biology Letters today, came as a surprise to the researchers.</p>
<p>“We found what we didn’t initially expect, which is that they’ve had this low immune gene diversity for a long, long time,” she said.</p>
<p>Her team analysed the DNA of devil specimens from both Tasmania and the Australian mainland going back 10,000 years.</p>
<p>“What we found was that all the Tasmanian samples, including those that were from before European arrival, had the same immune gene diversity as modern devils.”</p>
<p>“This is a trend that’s been going on for hundreds if not thousands of years, and it all occurred before the arrival of Europeans in Australia.”</p>
<p>But another, earlier population crash may have been responsible for thinning out the gene pool.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/18340/original/k58q9hcy-1354666314.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/18340/original/k58q9hcy-1354666314.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/18340/original/k58q9hcy-1354666314.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/18340/original/k58q9hcy-1354666314.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/18340/original/k58q9hcy-1354666314.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/18340/original/k58q9hcy-1354666314.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/18340/original/k58q9hcy-1354666314.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/18340/original/k58q9hcy-1354666314.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>
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">AAP/Devil Ark/Mandy Kennedy</span></span>
</figcaption>
</figure>
<p>“About 10,00 - 50,000 years ago, there was an extinction of large carnivores across the mainland of Australia, and it’s thought that this was either caused by the effect of humans, who had just arrived, or climate change that was going on,” she said.</p>
<p>“It’s possible that although devils survived this mass extinction, they may have had their population decreased, and due to the smaller population size, they lost genetic diversity.”</p>
<p>“It’s a possibility, but we can’t prove that at the moment.”</p>
<p>She said this research confirmed how important captive breeding programs were for conservation of Tasmanian devils.</p>
<p>Brandon Menzies, who has done similar work on the genetic diversity of the now-extinct Tasmanian tiger, said the results are signifcant.</p>
<p>“The results confirm a lack of genetic variation within a key immune gene cluster, known as MHC class I, prior to European settlement of Australia,” he said.</p>
<p>“The lack of diversity may have originated from population decline as a result of disease or competition from wild dogs that arrived in Australia during the <a href="http://www.ucmp.berkeley.edu/quaternary/holocene.php">Holocene period</a>.” </p>
<p>“The results reinforce our need to clarify both the modern and ancient diversity of our remaining marsupial populations to make them extinction-proof for future generations.”</p><img src="https://counter.theconversation.com/content/11167/count.gif" alt="The Conversation" width="1" height="1" />
European settlers were not responsible for thinning the gene pool of the Tasmanian devil, new research has found. Tasmanian devils are currently under threat due to the spread of an aggressive facial tumour…Megan Clement, Deputy Editor, Politics + SocietyLicensed as Creative Commons – attribution, no derivatives.