tag:theconversation.com,2011:/fr/topics/galapagos-islands-8099/articlesGalapagos Islands – The Conversation2022-11-01T13:37:52Ztag:theconversation.com,2011:article/1931232022-11-01T13:37:52Z2022-11-01T13:37:52ZLarge tortoises lived in South Africa long ago: how we recorded their fast-disappearing traces<figure><img src="https://images.theconversation.com/files/491294/original/file-20221024-5750-exbv3j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Today, leopard tortoises are the largest species found on the Cape south coast. </span> <span class="attribution"><span class="source">Ava Peattie/Shutterstock</span></span></figcaption></figure><p>In 1835 Charles Darwin, the father of the theory of evolution, was exploring an island in the Galápagos archipelago when he <a href="https://www.biodiversitylibrary.org/page/19698213#page/438/mode/1up">encountered</a> “two large tortoises, each of which must have weighed at least two hundred pounds”. He had never seen anything like them. He became entranced by the animals and took <a href="https://www.theguardian.com/science/animal-magic/2014/feb/12/celebrity-pet-discovery-darwin-tortoise">at least one</a> back to England as a pet.</p>
<p>Large tortoises are still associated with the Galápagos Islands, about 1,000km off the coast of Ecuador, as well as <a href="https://nationalzoo.si.edu/animals/aldabra-tortoise">Aldabra Island</a> in the Seychelles.</p>
<p>Now, for the first time, evidence has been found to suggest that a species of very large tortoise once lived on South Africa’s Cape south coast. <a href="https://www.doi.org/10.1017/qua.2022.50">Our study</a> of fossil tracks indicates that, between 139,000 and 109,000 years ago, a tortoise species existed that was around 106cm long. This is not as big as the Galápagos tortoises, which can reach 150cm or more in length, but is significantly bigger than any tortoises in southern Africa today.</p>
<p>The period when these tortoises were wandering round the southern tip of Africa was called the <a href="https://www.livescience.com/40311-pleistocene-epoch.html">Pleistocene Epoch</a>. They shared the landscape with large animals like <a href="http://dx.doi.org/10.17159/sajs.2018/20170266">giraffes</a>, extinct giant buffalo, <a href="https://doi.org/10.17159/sajs.2020/6542">crocodiles</a> and <a href="https://doi.org/10.1017/qua.2019.40">breeding sea turtles</a>, none of which inhabit the region today. Our ancestors, <em>Homo sapiens</em>, <a href="https://sajs.co.za/article/view/8156">were also present</a>.</p>
<p>Today, the leopard tortoise (<em>Stigmochelys pardalis</em>) is the largest tortoise species in the area. The record length for a leopard tortoise is 70cm. Given the length of the tortoise in our findings – 106cm – we conclude that either the tracks were made by a previously unknown very large tortoise or that the leopard tortoises of the Pleistocene period were much larger.</p>
<p>Before this research, there was nothing to suggest the presence of very large tortoises from southern Africa in the region’s extensive archaeological record and body fossil record. Such findings demonstrate the capacity of ichnology – the study of tracks and traces – to complement and fill gaps in the traditional fossil record. And doing so doesn’t just create a fuller picture of ancient landscapes: it’s an important part of understanding what’s changed over time and the effects of climate change and humans.</p>
<h2>Tracks</h2>
<p>The fossil tracks were found in aeolianites (cemented dunes) and were made when these deposits consisted of unconsolidated sand. These sites would have been situated at the margin of the vast <a href="https://doi.org/10.1016/j.quascirev.2019.106161">Palaeo-Agulhas Plain</a>, which was alternately exposed and inundated during Pleistocene sea level oscillations.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/492509/original/file-20221031-25-jh1obc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492509/original/file-20221031-25-jh1obc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492509/original/file-20221031-25-jh1obc.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492509/original/file-20221031-25-jh1obc.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492509/original/file-20221031-25-jh1obc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492509/original/file-20221031-25-jh1obc.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492509/original/file-20221031-25-jh1obc.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The aeolianite block, showing the large tortoise tracks and traces (scale bar = 10cm)</span>
<span class="attribution"><span class="source">Charles Helm</span></span>
</figcaption>
</figure>
<p>The main tracksite was located east of Still Bay, around 340km from Cape Town, on a rugged, remote stretch of coastal cliffs. Here we were fortunate to intercept a large aeolianite block on its slow but relentless journey from the cliffs above, from which it had broken off, down a sandy slope to the sea below. </p>
<p>When we initially identified it, the track-bearing surface was covered in a thin veneer of sediment which preserved exquisite detail. Not only were two sets of parallel large tracks evident, but a number of traces were also present centrally between these sets of tracks, indicating where something large had scraped the surface and caused shallow parallel striations and other deeper impressions. </p>
<p>It was a good thing we found the block when we did: within a couple of weeks the veneer (with the parallel striations) had been eroded away by wind and water. Months later the block had disappeared into the ocean. </p>
<h2>A large trackmaker</h2>
<p>By then we had already photographed and measured the block, the tracks and the surrounding area. We also took rock samples to perform dating studies from sites west and east of the main tracksite through a technique known as <a href="https://doi.org/10.1146/annurev-earth-040610-133425">optically stimulated luminescence</a> and established that the tracks were probably made between approximately 139,000 years and 109,000 years ago. </p>
<p>After ruling out other possibilities, including large crocodiles and monitor lizards, it was evident that this trackway had been made by a large tortoise, and that the midline features were caused by the dragging of the plastron (the underside of the tortoise shell) and by the tail spearing the surface. </p>
<p>The trackway was 69cm wide. We studied tracks and traces of leopard tortoises for comparison, and used these to estimate that the trackmaker at our site was as much as 106cm long, at least 50% longer than the largest recorded leopard tortoises.</p>
<h2>Changing sizes over time</h2>
<p>Many species of giant tortoises on islands have become extinct <a href="https://doi.org/10.3854/crm.5.000e.fossil.checklist.v1.2015">in the last few centuries</a>. It would also not be unprecedented if what was once a giant species had evolved into a smaller species, the extant leopard tortoise. Tortoise giantism is a <a href="https://doi.org/10.1111/cla.12227">recurring theme</a> in the fossil record. </p>
<p>It is known that <a href="https://doi.org/10.1016/0033-5894(86)90089-X">some carnivorans</a>, <a href="https://doi.org/10.2989/00306525.2020.1789772">birds</a> and <a href="https://doi.org/10.1111/geb.12491">reptiles</a> were larger in some phases of the Pleistocene than today, so both possibilities are plausible.</p>
<p>Our team’s latest discovery adds a little more to the picture that both our and other scientists’ findings have painted of the ancient Cape south coast landscape. With each find, the image becomes clearer – and allows us to understand how it has shifted over time.</p><img src="https://counter.theconversation.com/content/193123/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Charles Helm 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>Track marks are a way to fill in the blanks that sometimes exist in the body fossil record.Charles Helm, Research Associate, African Centre for Coastal Palaeoscience, Nelson Mandela UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1540202021-02-02T15:19:41Z2021-02-02T15:19:41ZGalápagos: we’ve found out why the islands are blessed with such nutrient-rich waters<figure><img src="https://images.theconversation.com/files/381720/original/file-20210201-23-43mwo4.jpg?ixlib=rb-1.1.0&rect=0%2C5%2C3866%2C2579&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Javarman / shutterstock</span></span></figcaption></figure><p>Every part of the Galápagos’s exceptional and distinctive ecosystem can be traced back to its rich reserves of marine algae. Some animals feed on the microscopic plants directly, others, in turn, feast on them, and so on. Many unique species found only on the Pacific archipelago such as the famous marine iguanas or flightless cormorants, ultimately get their food from this algae. </p>
<p>The abundance of algae – technically microscopic plants known as phytoplankton – is a result of a pool of unusually cold water that is often found to the west of the islands. This cold pool is a result of an upwelling of nutrient-rich deep ocean waters, which is weakest during the hot wet season (December to May) and strongest during the dry Garúa season (May to November).</p>
<p>Scientists have speculated for decades about what drives this Galápagos upwelling and, in the absence of conclusive evidence, some have inferred it is driven by an eastward-flowing current <a href="https://doi.org/10.1175/JPO-D-19-0110.1">colliding with the islands</a>. </p>
<p>But the key to unlocking the mystery of what causes the upwelling lies in its strong seasonality. First, we found that the coldness of the water to the west of the islands is connected to the strength of local northward winds. This is in marked contrast to the weaker upwelling that occurs throughout the wider equatorial Pacific Ocean, which is sustained by the strength of the prevailing westward winds.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/381981/original/file-20210202-23-n6gpu8.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="World map. Land is grey, sea is blue and green" src="https://images.theconversation.com/files/381981/original/file-20210202-23-n6gpu8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/381981/original/file-20210202-23-n6gpu8.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=366&fit=crop&dpr=1 600w, https://images.theconversation.com/files/381981/original/file-20210202-23-n6gpu8.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=366&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/381981/original/file-20210202-23-n6gpu8.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=366&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/381981/original/file-20210202-23-n6gpu8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=460&fit=crop&dpr=1 754w, https://images.theconversation.com/files/381981/original/file-20210202-23-n6gpu8.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=460&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/381981/original/file-20210202-23-n6gpu8.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=460&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Global map of chlorophyll (a measure of phytoplankton growth). The Galápagos sits in a current that sends nutrients through the ‘desert’ of the Pacific Ocean.</span>
<span class="attribution"><a class="source" href="https://earthobservatory.nasa.gov/global-maps/MY1DMM_CHLORA">NASA</a></span>
</figcaption>
</figure>
<p>But how exactly do these northward winds drive strong localised upwelling around the Galápagos? We recently explored this question for a study now published in <a href="https://www.nature.com/articles/s41598-020-80609-2">Scientific Reports</a>, in which we used a realistic, high-resolution computer model of ocean circulation in the region. We wanted the model to focus specifically on the effects of local wind strength, excluding as far as possible larger scale variables. This meant we modelled the ocean in its typical annual-mean state for factors like temperature, salinity and water velocity, and then “forced” it with six-hourly changes in atmospheric wind, radiation, precipitation and evaporation based on real-world observations. </p>
<p>To our surprise, this much simplified model was capable of closely reproducing the actual seasonal cycle of the Galápagos cold pool. Close analysis then pinpointed intense turbulent mixing in the ocean as the precise cause of the upwelling. What appears to be happening, to the west of the islands, is northward winds are blowing on so-called upper-ocean fronts – these are bands of abrupt lateral changes in seawater temperature, akin to but much smaller than atmospheric fronts in weather maps. When the wind hits the fronts, this mixes the warm surface water with cooler waters below, and provokes further circulation below the surface which draws still colder water up from the depths of the ocean.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/381975/original/file-20210202-21-1w2onpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A turtle with small colourful fish" src="https://images.theconversation.com/files/381975/original/file-20210202-21-1w2onpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/381975/original/file-20210202-21-1w2onpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/381975/original/file-20210202-21-1w2onpp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/381975/original/file-20210202-21-1w2onpp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/381975/original/file-20210202-21-1w2onpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/381975/original/file-20210202-21-1w2onpp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/381975/original/file-20210202-21-1w2onpp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Nutrient-rich water supports lots of spectacular marine life.</span>
<span class="attribution"><span class="source">Longjourneys / shutterstock</span></span>
</figcaption>
</figure>
<p>The cold-pool upwelling is highly productive, since more nutrients mean more phytoplankton which means more fish, and so on. The reproductive success of the Galápagos fur seal, Galápagos penguin, flightless cormorant and many other endemic species, is highly dependent upon this upwelling. The seasonal presence of endangered filter-feeding <a href="https://theconversation.com/whale-sharks-gather-at-a-few-specific-locations-around-the-world-now-we-know-why-98502">whale sharks</a> in the area is likely also related to these processes. Furthermore, Ecuador’s industrial tuna fleet, one of the largest in the world, concentrates on this region, as does the semi-industrial mainland-based longline fleet. </p>
<p>We then played with the exact location of the islands and their shape within our model. This confirmed that the Galápagos archipelago is almost perfectly positioned to maximise the strength of the wind-generated mixing. Without the upwelling generated by the mixing, phytoplankton growth around the islands would be closer to the more modest levels found much further west in the Pacific. And if this was the case, it would be much harder for the Galápagos to sustain its unique wealth of endemic species.</p>
<p>Our findings demonstrate that Galápagos upwelling is at the very least likely to be strongly influenced by highly localised interactions between the atmosphere and the ocean. This new knowledge will inform plans to expand the archipelago’s <a href="https://www.galapagosislands.com/blog/galapagos-marine-reserve-marine-sanctuary/">marine reserve</a> and help protect against the mounting pressures of climate change and <a href="https://theconversation.com/galapagos-how-to-protect-the-islands-amazing-marine-life-from-huge-chinese-fishing-fleets-144927">human exploitation</a>.</p><img src="https://counter.theconversation.com/content/154020/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alex Forryan received funding from the Royal Society.</span></em></p><p class="fine-print"><em><span>Alberto Naveira Garabato receives funding from the Royal Society and Wolfson Foundation. </span></em></p><p class="fine-print"><em><span>Alex Hearn receives funding from the Royal Society, PEW Charitable Trust and Galapagos Conservation Trust. He is affiliated with MigraMar, the Galapagos Whale Shark Project, Turtle Island Restoration Network and Fundación Megafauna Marina del Ecuador. </span></em></p>How Pacific winds interact with the sea to bring colder waters up from the depths.Alex Forryan, Research Fellow, National Oceanography Centre, University of SouthamptonAlberto Naveira Garabato, Professor, National Oceanography Centre, University of SouthamptonAlex Hearn, Professor, School of Biological and Environmental Sciences, Universidad San Francisco de Quito (Ecuador)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1429182020-07-21T19:49:38Z2020-07-21T19:49:38ZNew research reveals how Australia and other nations play politics with World Heritage sites<figure><img src="https://images.theconversation.com/files/348532/original/file-20200721-18366-n6sxl1.jpg?ixlib=rb-1.1.0&rect=8%2C0%2C5369%2C3579&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>Some places are considered so special they’re valuable to all humanity and must be preserved for future generations. These irreplaceable gems – such as Machu Picchu, Stonehenge, Yosemite National Park and the Great Barrier Reef – are known as World Heritage sites.</p>
<p>When these places are threatened, they can officially be placed on the “List of World Heritage in Danger”. This action brings global attention to the natural or human causes of the threats. It can encourage emergency conservation action and mobilise international assistance.</p>
<p>However, our <a href="https://rdcu.be/b5JCI">research</a> released today shows the process of In Danger listings is being manipulated for political gain. National governments and other groups try to keep sites off the list, with strategies such as lobbying, or partial efforts to protect a site. Australian government actions to keep the Great Barrier Reef off the list are a prime example.</p>
<p>These practices are a problem for many reasons – not least because they enable further damage to threatened ecosystems.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/348530/original/file-20200721-17-10xr3aj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/348530/original/file-20200721-17-10xr3aj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/348530/original/file-20200721-17-10xr3aj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/348530/original/file-20200721-17-10xr3aj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/348530/original/file-20200721-17-10xr3aj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/348530/original/file-20200721-17-10xr3aj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/348530/original/file-20200721-17-10xr3aj.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">Yosemite National Park is on the World Heritage list.</span>
<span class="attribution"><span class="source">AAP/Kathryn Bermingham</span></span>
</figcaption>
</figure>
<h2>What is the In Danger list?</h2>
<p>World Heritage sites represent outstanding socioeconomic, natural and cultural values. Nations vie to have their sites included on the World Heritage list, which can attract tourist dollars and international prestige. In return, the nations are responsible for protecting the sites.</p>
<p>World Heritage sites are protected by an international convention, overseen by the United Nations body UNESCO and its World Heritage Committee. The committee consists of representatives from 21 of the 193 nations signed up to the convention.</p>
<hr>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/we-just-spent-two-weeks-surveying-the-great-barrier-reef-what-we-saw-was-an-utter-tragedy-135197">We just spent two weeks surveying the Great Barrier Reef. What we saw was an utter tragedy</a>
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<p>When a site comes under threat, the World Heritage Committee can list the site as <a href="https://whc.unesco.org/en/danger/">in danger</a> of losing its heritage status. In 2014 for example, the committee threatened to list the Great Barrier Reef as In Danger – in part due to a plan to dump dredged sediment from a port development near the reef, as well as poor water quality, climate change and other threats. This listing did not eventuate.</p>
<p>An In Danger listing can attract help to protect a site. For example, the Galápagos Islands were <a href="https://www.iucn.org/content/galapagos-islands-added-world-heritage-danger-list">placed on the list</a> in 2007. The World Heritage Fund provided the Ecuadorian government with technical and financial assistance to restore the site’s World Heritage status. The work is not yet complete, but the islands were removed from the In Danger list in 2010.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/348535/original/file-20200721-151933-11owh6b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/348535/original/file-20200721-151933-11owh6b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=429&fit=crop&dpr=1 600w, https://images.theconversation.com/files/348535/original/file-20200721-151933-11owh6b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=429&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/348535/original/file-20200721-151933-11owh6b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=429&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/348535/original/file-20200721-151933-11owh6b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=539&fit=crop&dpr=1 754w, https://images.theconversation.com/files/348535/original/file-20200721-151933-11owh6b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=539&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/348535/original/file-20200721-151933-11owh6b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=539&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Ecuador’s Galapagos Islands were removed from the In Danger list in 2010.</span>
<span class="attribution"><span class="source">EPA</span></span>
</figcaption>
</figure>
<h2>Political games</h2>
<p>Our <a href="https://doi.org/10.1038/s41893-020-0568-8">study</a> shows political manipulation appears to be compromising the process that determines if a site is listed as In Danger. </p>
<p>We examined interactions between UNESCO and 102 national governments, from 1972 until 2019. We interviewed experts from the World Heritage Committee, government agencies and elsewhere, and combined this with global site threat data, UNESCO and government records, and economic and governance data.</p>
<p>We found at least 41 World Heritage sites, including the Great Barrier Reef, were at least once considered by the World Heritage Committee for the In Danger list, but weren’t put on it. This is despite these sites being reported by UNESCO as threatened, or more threatened, than those already on the In Danger list. And 27 of the 41 sites were considered for an In Danger listing more than once.</p>
<p>The number of sites on the In Danger list declined by 31.6% between 2001 and 2008, and has plateaued since. By 2019, only 16 of 238 ecosystems were certified as In Danger. In contrast, the number of ecosystems on the World Heritage list has increased steadily over the past 20 years.</p>
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Read more:
<a href="https://theconversation.com/explainer-what-is-the-list-of-world-heritage-in-danger-15679">Explainer: what is the List of World Heritage in Danger?</a>
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<p>So why is this happening? Our analysis showed the threat of an In Danger listing drives a range of government responses.</p>
<p>This includes governments complying only partially with World Heritage Committee recommendations or making only symbolic commitments. Such “rhetorical” adoption of recommendations has been seen in relation to the Three Parallel Rivers in China’s Yunnan province, the Western Caucasus in Russia and Australia’s Great Barrier Reef (explored in more detail below).</p>
<p>In other cases, threats to a site are high but attract limited attention and effort from either the national government or UNESCO. These sites include Halong Bay in Vietnam and the remote Tubbataha Reefs in the Philippines.</p>
<p>A 2004 amendment to the way the World Heritage Committee assesses In Danger listings means sites can be “considered” for inclusion rather than just listed, retained or removed. This has allowed governments to use <a href="https://wwfeu.awsassets.panda.org/downloads/ournaturalworldatriskreport.pdf">delay tactics</a>, such as in the case of Cameroon’s Dja Faunal Reserve. It has been considered for the In Danger list five times since 2011, but never listed.</p>
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<span class="caption">Threats to Vietnam’s Halong Bay receive little attention.</span>
<span class="attribution"><span class="source">Richard Vogel/AAP</span></span>
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<h2>Case in point: The Great Barrier Reef</h2>
<p>In 2014 and 2015, the Australian government spent more than A$400,000 on overseas <a href="https://www.smh.com.au/politics/federal/government-spent-at-least-400000-lobbying-against-great-barrier-reef-danger-listing-20150914-gjlwr2.html">lobbying trips</a> to keep the Great Barrier Reef off the In Danger list. The environment minister and senior bureaucrats travelled to most of the 21 countries on the committee, plus other nations, to argue against the listing. <a href="https://www.smh.com.au/politics/federal/great-barrier-reef-mining-industry-told-foreign-journalists-ports-not-a-danger-20150525-gh8uwt.html">The mining industry</a> also contributed to the lobbying effort.</p>
<p>The World Heritage Committee had asked Australia to develop a long-term plan to protect the reef. The Australian and Queensland governments appeared to comply, by releasing the <a href="https://www.environment.gov.au/system/files/resources/d98b3e53-146b-4b9c-a84a-2a22454b9a83/files/reef-2050-long-term-sustainability-plan.pdf">Reef 2050 Plan</a> in 2015. </p>
<p>But in 2018, a <a href="https://www.anao.gov.au/sites/default/files/Auditor-General_Report_2018-2019_22.pdf">national audit</a> and <a href="https://www.aph.gov.au/Parliamentary_Business/Committees/Senate/Environment_and_Communications/GBRPartnershipProgram/Report">Senate inquiry</a> found a substantial portion of finance for the plan was delivered – in a non-competitive and hidden process – to the private Great Barrier Reef Foundation, which had limited capacity and expertise. This casts doubt over whether the aims of the reef plan can be achieved.</p>
<h2>Real world damage</h2>
<p>Our study makes no recommendation on which World Heritage sites should be listed as In Danger. But it uncovered political manipulation that has real-world consequences. Had the Great Barrier Reef been listed as In Danger, for example, developments potentially harmful to the reef, such as the <a href="https://www.bbc.co.uk/programmes/b09tds6z">Adani coal mine</a>, may have struggled to get approval.</p>
<p>Last year, an <a href="http://www.gbrmpa.gov.au/our-work/outlook-report-2019">outlook report</a> gave the reef a “very poor” prognosis and last summer the reef suffered its <a href="https://www.coralcoe.org.au/media-releases/climate-change-triggers-great-barrier-reef-bleaching">third mass bleaching</a> in five years. There are grave concerns for the ecosystem’s ability to recover before yet another bleaching event.</p>
<p>Political manipulation of the World Heritage process undermines the usefulness of the In Danger list as a policy tool. Given the global investment in World Heritage over the past 50 years, it is essential to address the hidden threats to good governance and to safeguard all ecosystems.</p>
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Read more:
<a href="https://theconversation.com/australia-reprieved-now-it-must-prove-it-can-care-for-the-reef-42330">Australia reprieved – now it must prove it can care for the Reef</a>
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<img src="https://counter.theconversation.com/content/142918/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tiffany Morrison receives funding from the Australian Research Council.</span></em></p><p class="fine-print"><em><span>Katrina Brown receives funding from UK Research and Innovation. </span></em></p><p class="fine-print"><em><span>Neil Adger receives funding from UK Research and Innovation, the International Development Research Centre, and the Wellcome Trust. </span></em></p><p class="fine-print"><em><span>Maria Lemos 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>National governments are using political lobbying and empty symbolic efforts to stave off an “in danger” listing for their World Heritage sites.Tiffany Morrison, Professorial Research Fellow, ARC Centre of Excellence for Coral Reef Studies, James Cook UniversityKatrina Brown, Professor of Social Sciences, University of ExeterMaria Lemos, Professor of Environmental Justice, Environmental Policy and Planning, Climate + Energy,, University of MichiganNeil Adger, Professor of Human Geography, University of ExeterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1185862019-06-12T06:09:58Z2019-06-12T06:09:58ZA parasite attack on Darwin’s finches means they’re losing their lovesong<figure><img src="https://images.theconversation.com/files/278820/original/file-20190611-32351-1hoo5hb.jpg?ixlib=rb-1.1.0&rect=29%2C196%2C2710%2C1683&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A Small Tree Finch from the Galápagos Islands with an enlarged nostril caused by a parasite.</span> <span class="attribution"><span class="source">Katharina J Peters</span>, <span class="license">Author provided</span></span></figcaption></figure><p>A parasite known to infect beaks in some iconic Darwin finches on the Galapagos Islands is changing the mating song of male birds.</p>
<p>Our research, <a href="http://rspb.royalsocietypublishing.org/lookup/doi/10.1098/rspb.2019.0461" title="Introduced parasite changes host phenotype, mating signal and hybridisation risk: Philornis downsi effects on Darwin’s finch song">published today in Proceedings of the Royal Society B</a>, reveals how the parasite deforms the beak. This has the effect of weakening the male bird’s mating call, and making it no longer clearly distinguishable from that of other closely related species.</p>
<p>A changed song can have an important effect on the male finch’s ability to find a mate. </p>
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Read more:
<a href="https://theconversation.com/simply-returning-rescued-wildlife-back-to-the-wild-may-not-be-in-their-best-interest-118521">Simply returning rescued wildlife back to the wild may not be in their best interest</a>
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<p>It’s another factor that could contribute to declining numbers of these already threatened birds on the Pacific archipelago, about 1,000km off the coast of South America.</p>
<h2>A family song to impress</h2>
<p>A male finch learns the mating song from his father, and produces the same song for the <a href="https://www.pnas.org/content/107/47/20156/tab-article-info" title="Songs of Darwin's finches diverge when a new species enters the community">rest of his life</a>.</p>
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<p>It’s a simple tune consisting of one syllable repeated 3 to 15 times, depending on what species of finch he belongs to. Larger-bodied finch species produce a slower song with few syllable repeats, and smaller-bodied finch species produce faster song with <a href="https://www.cambridge.org/core/journals/bird-conservation-international/article/avian-population-trends-in-scalesia-forest-on-floreana-island-20042013-acoustical-surveys-cannot-detect-hybrids-of-darwins-tree-finches-camarhynchus-spp/7FE5D763A26BC9C0398398DE336CB778">many syllable repeats</a>.</p>
<p>Whatever species of finch you belong to, hitting the high notes is important – because females prefer males who can produce such vocally challenging songs. </p>
<p>In the case of the <a href="https://link.springer.com/article/10.1007/s10531-009-9740-1">Medium Tree Finch</a> (<em>Camarhynchus pauper</em>), a critically endangered species that only occurs on Floreana Island of the Galapagos Islands, its species-typical song has a bright resonance that rings across the forest canopy.</p>
<p><audio preload="metadata" controls="controls" data-duration="2" data-image="" data-title="Medium Tree Finch" data-size="36361" data-source="" data-source-url="" data-license="Author provided" data-license-url="">
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Medium Tree Finch.
<span class="attribution"><span class="license">Author provided</span><span class="download"><span>35.5 KB</span> <a target="_blank" href="https://cdn.theconversation.com/audio/1607/medium-tree-finch-with-normal-naris-size.mp3">(download)</a></span></span>
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<p>An accomplished male singer that can hit the high notes is quickly swooped up by a female looking to pair with a proficient singer. </p>
<h2>The ‘Vampire’ parasite</h2>
<p>The Vampire Fly – a <a href="https://twitter.com/CStenoien/status/1110602027275571200">suggested name</a> for the parasite <em>Philornis downsi</em> given its blood feeding habits from dusk until dawn – was <a href="https://onlinelibrary.wiley.com/doi/full/10.1046/j.1474-919X.2002.00076.x" title="Philornis downsi– a recently discovered parasite on the Galápagos archipelago – a threat for Darwin's finches?">first discovered in a Darwin’s finch nest in 1997</a>.</p>
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<a href="https://images.theconversation.com/files/279035/original/file-20190612-32317-1tai1zv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/279035/original/file-20190612-32317-1tai1zv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/279035/original/file-20190612-32317-1tai1zv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/279035/original/file-20190612-32317-1tai1zv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/279035/original/file-20190612-32317-1tai1zv.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/279035/original/file-20190612-32317-1tai1zv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/279035/original/file-20190612-32317-1tai1zv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/279035/original/file-20190612-32317-1tai1zv.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The parasitic <em>Philornis</em> larvae in a finch nest.</span>
<span class="attribution"><span class="source">Sonia Kleindorfer</span>, <span class="license">Author provided</span></span>
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<p>Since then, the devastating impacts of its larval feeding habits on nestling birds have been <a href="https://www.cambridge.org/core/journals/parasitology/article/lifecycle-of-philornis-downsi-diptera-muscidae-parasitizing-darwins-finches-and-its-impacts-on-nestling-survival/597D469905598A7105BBE59990009B32">coming to light</a>. The adult fly is vegetarian, but the females lay their eggs into bird nests and their <a href="https://bmczool.biomedcentral.com/articles/10.1186/s40850-016-0003-9" title="Host-parasite ecology, behavior and genetics: a review of the introduced fly parasite Philornis downsi and its Darwin’s finch hosts">larvae feed on nestling bird beaks from the inside out</a>. </p>
<p>Many Darwin’s finch species now have beaks with massively enlarged nostrils because of damage the feeding fly larvae have caused <a href="https://www.sciencedirect.com/science/article/pii/S2351989416300336?via%3Dihub" title="Naris deformation in Darwin’s finches: Experimental and historical evidence for a post-1960s arrival of the parasite Philornis downsi">during the nestling stage</a>. We discovered that a changed beak apparatus measurably affects the song of Darwin’s tree finches with consequences for pairing success. </p>
<p>A Medium Tree Finch male with extremely enlarged nostrils is unable to hit the high notes.</p>
<p><audio preload="metadata" controls="controls" data-duration="2" data-image="" data-title="Medium Tree Finch with enlarged nostrils" data-size="33017" data-source="" data-source-url="" data-license="Author provided" data-license-url="">
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Medium Tree Finch with enlarged nostrils.
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<p>We found the same pattern in Small Tree Finches (<em>C. parvulus</em>) with enlarged nostrils. </p>
<p>Male finches that produce song with a narrower frequency bandwidth, because their song has a lower maximum frequency, have poor quality song. These males are less likely to be chosen by females, a pattern we documented in both the Medium Tree Finch and the Small Tree Finch.</p>
<p>Also, the song of Medium Tree Finches with enlarged nostrils sounds like the song of the Small Tree Finch.</p>
<p><audio preload="metadata" controls="controls" data-duration="1" data-image="" data-title="Small Tree Finches" data-size="29674" data-source="" data-source-url="" data-license="Author provided" data-license-url="">
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Small Tree Finches.
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<h2>When species merge</h2>
<p>But confusion among the species and their mating songs may not necessarily be a bad thing for the future survival of individual finches – though it could herald the collapse of species lineages.</p>
<p>Previously, we discovered evidence of <a href="https://www.ncbi.nlm.nih.gov/pubmed/24561597" title="Species collapse via hybridization in Darwin's tree finches">hybridisation in Darwin finches</a>. This is where two separate species of finch breed which could potentially produce a new species, phase out one of the species, or cause the collapse of the two existing species into one.</p>
<p>We observed hybridisation driven by <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/jeb.13167" title="Females drive asymmetrical introgression from rare to common species in Darwin's tree finches">female Medium Tree Finches</a> pairing with male Small Tree Finches. </p>
<p>When a female Medium Tree Finch inspects male Small Tree Finches in the forest, she pairs with one who produces high quality song, even if that male is from another species.</p>
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<a href="https://images.theconversation.com/files/279048/original/file-20190612-32361-ve8cs4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/279048/original/file-20190612-32361-ve8cs4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/279048/original/file-20190612-32361-ve8cs4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/279048/original/file-20190612-32361-ve8cs4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/279048/original/file-20190612-32361-ve8cs4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/279048/original/file-20190612-32361-ve8cs4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/279048/original/file-20190612-32361-ve8cs4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/279048/original/file-20190612-32361-ve8cs4.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>
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<span class="caption">A Tree Finch with a normal beak and nostril size, so no infection from the parasite.</span>
<span class="attribution"><span class="source">Katharina J Peters</span>, <span class="license">Author provided</span></span>
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<p>This female choice seems to be paying dividends, because hybrid pairs with greater genetic diversity also sustained <a href="https://royalsocietypublishing.org/doi/10.1098/rsos.181616" title="Genetic admixture predicts parasite intensity: evidence for increased hybrid performance in Darwin's tree finches">fewer of the parasitic larvae in the nest</a>. And that could lead to fewer birds with infected beaks.</p>
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Read more:
<a href="https://theconversation.com/galapagos-species-are-threatened-by-the-very-tourists-who-flock-to-see-them-86392">Galapagos species are threatened by the very tourists who flock to see them</a>
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<p>There are concerted efforts underway to develop control and eradication methods for <em>P. downsi</em> on the Galapagos Islands, building on a collaborative relationship between the Charles Darwin Foundation and the Galapagos National Parks. The <a href="https://www.darwinfoundation.org/en/research/projects/philornis-downsi"><em>Philornis downsi</em> Action Group</a> is an international consortium of concerned scientists working to develop biological control methods.</p>
<p>Our new research is an important step towards understanding how this invasive fly may be changing the evolutionary pathway of Darwin’s finches by literally changing the beak of the finch.</p><img src="https://counter.theconversation.com/content/118586/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>For this project the authors received funding from the Australian Research Council, the Max Planck Institute for Ornithology, the Mohamed bin Zayed Species Conservation Fund, the Ecological Society of Australia, Earthwatch Institute, Club300 Bird Protection, Rufford Small Grants Foundation, the Winifred Violet Scott Trust, the American Bird Conservancy, the Conservation International, the Australian Federation for University Women, and the Royal Society for the Protection of Birds/Birdfair. TAME airlines provided reduced airfares.
Katharina J. Peters is affiliated with Flinders University, Adelaide, Australia, and Massey University, Albany, New Zealand. </span></em></p><p class="fine-print"><em><span>Sonia Kleindorfer 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>An infestation as a chick leads to enlarged nostrils in the beak of Darwin finches, and that affects their mating call.Katharina J. Peters, Postdoctoral fellow, Flinders UniversitySonia Kleindorfer, Professor of Animal Behaviour, Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/886542017-12-05T15:01:03Z2017-12-05T15:01:03ZSea lions have unique whiskers that help them catch even the fastest fish<p>Astounding footage of Galapagos sea lions hunting was perhaps the highlight of the latest <a href="http://www.bbc.co.uk/programmes/b09hs07h">Blue Planet II</a>. For the first time ever, these marine mammals were filmed working as a pack to drive tuna fish in to shallow, rocky waters where they could be caught. Yellowfin tuna are typically able to outswim all predators but the fastest sharks and marlins, yet the much slower sea lions were able to outsmart them thanks to an amazing display of movement and cooperation.</p>
<p>I’ve studied these animals for years as I’m fascinated by their remarkable whiskers. So what is it about sea lions that makes them such excellent hunters? Here are three of their key adaptations:</p>
<h2>Superb sensing</h2>
<p>One of the things you can see clearly in the Blue Planet II footage is just how quickly the sea lions respond to the movements of the fish. They are able to sense exactly where the fish are and react almost instantly, in order to herd them towards shallow waters.</p>
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<p>Sea lions have amazing senses that allow them to detect fish, even in murky underwater environments. Like many predators, their eyes point forward so that they can easily focus on their prey. They can also open their pupils really wide to let <a href="http://www.nrcresearchpress.com/doi/abs/10.1139/z97-838?journalCode=cjz#.Wiaizk27LIU">lots of light in to their eye</a> which helps them to see clearly underwater.</p>
<p>However, sea lions aren’t always blessed with the clear waters of the Galapagos coastline. In really murky environments, sometimes vision is just not good enough. For this reason, sea lions primarily rely on their sense of touch, using their super-sensitive whiskers to feel exactly where the fish are in the water. When fish swim around they leave little waves, or wakes, behind them. Sea lions are able to <a href="https://link.springer.com/article/10.1007%2Fs00359-010-0594-5">detect these wakes and follow them</a>, just by using their whiskers.</p>
<p>Most mammals have facial whiskers (humans are unusual in that regard) which, when cut in cross-section, are circular. But sea lion whiskers are oval. Research has shown this is the best shape to <a href="http://blogs.plos.org/everyone/2013/09/10/whisker-shape-and-orientation-help-seals-and-sea-lions-minimize-self-noise/">sense the speed and direction of the wakes</a> while minimising the vibrating “noise” created by the sea lion’s own swimming. </p>
<p>At around 30cm, these are the longest whiskers of all mammals. They can move them backwards and forwards. Much like we use our finger tips for touch, sea lions can <a href="https://link.springer.com/article/10.3758/BF03199008">sweep their whiskers over objects</a> to feel their size, shape and texture. These same skills mean those in the wild can find the biggest and tastiest fish, just by touching them with their whiskers. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"916216480294981632"}"></div></p>
<p>Sea lions communicate using various “barks”, grunts and growls, especially when they are hunting as a group. They have ears that are able to pick up sounds both above and below water. However, their ears are very small, so they can still be super streamlined in the water.</p>
<h2>Quick moving</h2>
<p>This streamlining means the sea lions are able to move quickly and efficiently through the water. Front flippers are used to push themselves along, while back flippers are used for steering. They’re able to chase fish at speeds of <a href="https://books.google.co.uk/books?id=McNEUgU8Q58C&pg=PA7&dq=sea+lion+swimming+speeds&hl=en&sa=X&ved=0ahUKEwiQ9JWajvPXAhVGUhQKHRmRA2cQ6AEIMjAC#v=onepage&q=sea%20lion%20swimming%20speeds&f=false">around 25mph</a> but are flexible enough to quickly change direction.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/197810/original/file-20171205-22982-5g4b2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/197810/original/file-20171205-22982-5g4b2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/197810/original/file-20171205-22982-5g4b2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/197810/original/file-20171205-22982-5g4b2e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/197810/original/file-20171205-22982-5g4b2e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/197810/original/file-20171205-22982-5g4b2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/197810/original/file-20171205-22982-5g4b2e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/197810/original/file-20171205-22982-5g4b2e.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">Fishing in the Galapagos.</span>
<span class="attribution"><span class="source">JS Lamy / shutterstock</span></span>
</figcaption>
</figure>
<p>Sea lions use their whiskers to guide these fast changes in direction. For example, captive sea lions who have learned to balance balls on their noses have been shown to move their whiskers ahead of their heads to <a href="https://link.springer.com/article/10.1007/s00359-014-0931-1">sense and control the ball</a>. During swimming, they use their whiskers in a similar way and move their whiskers ahead of a full turn, so the whiskers are constantly scanning the space that the head and body are about to move in to. This also means that the whiskers constantly face towards the fish that the sea lion is trying to catch.</p>
<h2>Clever cognition</h2>
<p>As well as their amazing sensing abilities and quick movements, sea lions are also very clever and display many behaviours that we often only associate with humans. For instance, they are one of the only animals able to <a href="https://pinnipedlab.ucsc.edu/publications/pub_155_2013.pdf">bob their heads along to a piece of music</a>. They are also very quick to learn new behaviours, which is why they are so common to see in zoo and aquarium displays.</p>
<p>Indeed, the group hunting footage, shows the sea lions are not simply reacting to the fish, but acting out a complex series of well thought out behaviours.</p>
<p>Hunting together can increase the chances of getting more prey when there are large groups of fish. Usually sea lions hunt together by herding fish in to tight balls and picking off the individuals around the edges. Sea lions seem to know when it is good to hunt together, and usually do so when prey is abundant. They tend to hunt individually <a href="https://academic.oup.com/jmammal/article-abstract/47/2/195/904157">when prey is scarce</a>.</p>
<p>The remarkable footage from Blue Planet II really reveals what fantastic predators sea lions are. Their whisker-sensing strategies, quick acrobatic movements, and clever cognitive abilities make them ideally suited to hunting speedy fish like tuna.</p><img src="https://counter.theconversation.com/content/88654/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Robyn Grant receives funding from the UK Engineering and Physical Sciences Research Council. She works for Manchester Metropolitan University, in collaboration with Blackpool Zoo.</span></em></p>Blue Planet II reveals what fantastic predators they are.Robyn Grant, Senior Lecturer in Comparative Physiology & Behaviour, Manchester Metropolitan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/863922017-10-30T19:02:41Z2017-10-30T19:02:41ZGalapagos species are threatened by the very tourists who flock to see them<figure><img src="https://images.theconversation.com/files/191950/original/file-20171026-28071-14mtglf.jpg?ixlib=rb-1.1.0&rect=30%2C408%2C4076%2C2129&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Life's not such a beach for Galapagos native species these days.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/sea-lion-family-perfect-beach-galapagos-739969879?src=CDitVCmj--4FEFof5xE-fg-1-60">shacharf/shutterstock</a></span></figcaption></figure><p>Native species are <a href="http://advances.sciencemag.org/content/3/10/e1603080">particularly vulnerable on islands</a>, because when invaders such as rats arrive, the native species have nowhere else to go and may lack the ability to fend them off.</p>
<p>The main characteristic of an island is its isolation. Whether just off the coast or hundreds of kilometres from the nearest land, they stand on their own. Because of their isolation, islands generally have a unique array of plant and animal species, many of which are found nowhere else. And that makes all islands one of a kind.</p>
<p>However, islands, despite being geographically isolated, are now part of a network. They are globally connected to the outside world by planes, boats and people. Their isolation has been breached, offering a <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2664.2007.01442.x/full">pathway for introduced species to invade</a>.</p>
<p>The Galapagos Islands, 1,000km off the coast of Ecuador, provide a great example. So far, <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0184379">1,579 introduced species</a> have been documented on the Galapagos Islands, of which 98% arrived with humans, either intentionally or accidentally.</p>
<p>More than 70% of these species have arrived since the 1970s – when Galapagos first became a tourist destination – an average of 27 introduced species per year for the past 40 years. </p>
<h2>New arrivals</h2>
<p>Introduced species – plants or animals that have been artificially brought to a new location, often by humans – can damage native fauna and flora. They are among the top threats to biodiversity worldwide, and one of the <a href="https://portals.iucn.org/library/efiles/documents/Rep-2000-052.pdf">most important threats</a> to oceanic islands. The <a href="https://www.cbd.int/sp/">Convention on Biological Diversity</a> has a <a href="https://www.cbd.int/doc/strategic-plan/2011-2020/Aichi-Targets-EN.pdf">dedicated target</a> to help deal with them and their means of arrival. The target states that:</p>
<blockquote>
<p>by 2020, invasive alien species and pathways are identified and prioritised, priority species are controlled or eradicated and measures are in place to manage pathways to prevent their introduction and establishment.</p>
</blockquote>
<p>The Galapagos Islands are home to giant tortoises, flightless cormorants, and the iconic Darwin’s finches – species that have evolved in isolation and according to the differing characteristics of each of the islands. </p>
<p>However, the Galapagos’ natural attributes have also made these islands a top tourist destination. Ironically enough, this threatens the survival of many of the species that make this place so unique.</p>
<h2>Humans on the rise</h2>
<p>In 1950 the Galapagos Islands had just 1,346 residents, and no tourists. In 2015 <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0184379">more than 220,000 visitors</a> travelled to the islands. These tourists, along with the 25,000 local residents, need to have most of their food and other goods shipped from mainland Ecuador.</p>
<p>These strengthening links between Galapagos and the mainland have opened up pathways for the arrival and spread of introduced species to the archipelago, and between its various islands. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/191975/original/file-20171026-28041-4x2rta.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/191975/original/file-20171026-28041-4x2rta.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/191975/original/file-20171026-28041-4x2rta.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=457&fit=crop&dpr=1 600w, https://images.theconversation.com/files/191975/original/file-20171026-28041-4x2rta.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=457&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/191975/original/file-20171026-28041-4x2rta.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=457&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/191975/original/file-20171026-28041-4x2rta.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=574&fit=crop&dpr=1 754w, https://images.theconversation.com/files/191975/original/file-20171026-28041-4x2rta.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=574&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/191975/original/file-20171026-28041-4x2rta.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=574&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Major species transport routes into and between the Galapagos Islands.</span>
<span class="attribution"><a class="source" href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0184379#pone-0184379-t001">PLoS ONE</a></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/191981/original/file-20171026-28033-rn1uxl.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/191981/original/file-20171026-28033-rn1uxl.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/191981/original/file-20171026-28033-rn1uxl.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=419&fit=crop&dpr=1 600w, https://images.theconversation.com/files/191981/original/file-20171026-28033-rn1uxl.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=419&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/191981/original/file-20171026-28033-rn1uxl.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=419&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/191981/original/file-20171026-28033-rn1uxl.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=527&fit=crop&dpr=1 754w, https://images.theconversation.com/files/191981/original/file-20171026-28033-rn1uxl.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=527&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/191981/original/file-20171026-28033-rn1uxl.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=527&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">More and more alien species are finding their way to the Galapagos Islands.</span>
<span class="attribution"><a class="source" href="http://journals.plos.org/plosone/article/figure?id=10.1371/journal.pone.0184379.g003">PLoS ONE</a></span>
</figcaption>
</figure>
<p>Plants were the most common type of introduced species, followed by insects. The most common pathway for species introduction unintentionally was as a contaminant on plants. A few vertebrates have also been recorded as stowaways in transport vehicles, including snakes and opossums; whilst others have been deliberately introduced in the last decade (such as Tilapia, dog breeds and goldfishes).</p>
<p>The number, frequency and geographic origin of alien invasion pathways to Galapagos have increased through time. Our <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0184379">research</a> shows a tight relationship between the number of pathways and the ongoing increase in human population in Galapagos, from both residents and tourists.</p>
<p>For instance, the number of flights has increased from 74 flights a week in 2010 to 107 in 2015; the number of airplane passengers has also increased through time with about 40% being tourists, the remainder being Galapagos residents or transient workers.</p>
<p>Global connections between Galapagos and the outside world have also increased, receiving visitors from 93 countries in 2010 to 158 in 2014. In 2015 and 2016, the Galapagos Biosecurity Agency intercepted more than 14,000 banned items, almost 70% of which were brought in by tourists.</p>
<iframe id="datawrapper-chart-rlNIe" src="https://datawrapper.dwcdn.net/rlNIe/2/" scrolling="no" frameborder="0" allowtransparency="true" allowfullscreen="allowfullscreen" webkitallowfullscreen="webkitallowfullscreen" mozallowfullscreen="mozallowfullscreen" oallowfullscreen="oallowfullscreen" msallowfullscreen="msallowfullscreen" style="width: 0; min-width: 100% !important;" height="180" width="100%"></iframe>
<p>We think it likely that intentional introductions of alien species will decline when biosecurity is strengthened. However, with <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0140833">tourists</a> as known vectors for introduced species and with tourism much the <a href="http://www2.unwto.org/annualreport2014">largest and fastest</a> growing sector of the local economy, unintentional introductions to Galapagos will almost certainly increase further.</p>
<p>If islands are to be kept as islands, isolated in the full sense of the word, it is of high priority to manage their invasion pathways. Our research aims to provide technical input to local decision makers, managers and conservation bodies working in Galapagos in order to minimise a further increase on the number of available pathways to Galapagos and the probable likelihood of new arrivals. Our next step is to evaluate how local tourism boats are connecting the once isolated islands within Galapagos, as a way to minimise further spread of harmful introduced species to this UNESCO World Heritage Site.</p><img src="https://counter.theconversation.com/content/86392/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Veronica Toral-Granda is supported by an International Postgraduate Research Scholarship (IPRS) and an Australian Postgraduate Award (APA) scholarship to Charles Darwin University.</span></em></p><p class="fine-print"><em><span>Stephen Garnett 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>More than 1,500 introduced species have been recorded on the Galapagos Islands, and most have arrived since the archipelago’s tourism industry was expanded in the 1970s.Veronica Toral-Granda, PhD candidate, Charles Darwin UniversityStephen Garnett, Professor of Conservation and Sustainable Livelihoods, Charles Darwin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/760182017-04-19T19:45:49Z2017-04-19T19:45:49Z‘Sustainable tourism’ is not working – here’s how we can change that<figure><img src="https://images.theconversation.com/files/165521/original/image-20170418-32703-1lmfri6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Trips to Antartica are part of the 'last chance' tourism to environmentally fragile places.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>This year is the United Nations’ <a href="http://www.tourism4development2017.org/">International Year of Sustainable Tourism for Development</a>. UN World Tourism Organisation Secretary-General Taleb Rifai <a href="http://media.unwto.org/press-release/2015-12-07/united-nations-declares-2017-international-year-sustainable-tourism-develop">declared</a> it gave:</p>
<blockquote>
<p>… a unique opportunity to advance the contribution of the tourism sector to the three pillars of sustainability – economic, social and environmental, while raising awareness of the true dimensions of a sector which is often undervalued.</p>
</blockquote>
<p>Sustainable tourism comes from the concept of sustainable development, as set out in the <a href="http://www.un-documents.net/our-common-future.pdf">1987 Brundtland report</a>. Sustainable development <a href="http://www.unece.org/oes/nutshell/2004-2005/focus_sustainable_development.html">is</a>:</p>
<blockquote>
<p>… development which meets the needs of current generations without compromising the ability of future generations to meet their own needs. </p>
</blockquote>
<p>British environmental activist George Monbiot <a href="http://www.monbiot.com/2012/06/22/how-sustainability-became-sustained-growth/">argued that</a>, over the years, sustainable development has morphed into sustained growth. The essence of his argument is that little resolve exists to go beyond rhetoric. This is because environmental crises require we limit the demands we place on it, but our economies require endless growth.</p>
<p><a href="https://www.cabdirect.org/cabdirect/abstract/20103203885">At the moment</a>, economic growth trumps environmental limits, so sustainability remains elusive.</p>
<h2>What is sustainable tourism?</h2>
<p>Tourism is important to our efforts to achieve sustainable development. It is a massive industry, and many countries rely on it for their economies. </p>
<p>In 2016, more than 1.2 billion people travelled as tourists internationally, and another 6 billion people travelled domestically.</p>
<p><a href="http://sdt.unwto.org/content/about-us-5)">According to</a> the UN World Tourism Organisation, sustainable tourism is:</p>
<blockquote>
<p>… tourism that takes full account of its current and future economic, social and environmental impacts, addressing the needs of visitors, the industry, the environment and host communities. </p>
</blockquote>
<p>Following on from Monbiot’s criticism, we might ask if efforts are directed at “sustaining tourism”, or instead harnessing tourism for wider sustainable development goals.</p>
<h2>No place is off the tourism circuit</h2>
<p>Looking at some of the tourism trouble spots, complacency is not called for. </p>
<p>Venice residents <a href="http://www.news.com.au/travel/world-travel/europe/venetians-brandish-trolleys-and-prams-to-protest-tourism/news-story/53d45c0af91ee97fba17730ac8c3a3c5">have accused tourists</a> of “destroying their city”. Barcelona’s government has <a href="http://www.cntraveler.com/story/barcelona-approves-new-law-to-limit-tourist-numbers">passed legislation</a> to limit new tourist accommodation. The Galapagos sees <a href="https://www.theguardian.com/travel/blog/2007/jan/18/cantourismtothegalpagosev">mass tourism’s arrival</a> threatening the iconic wildlife that attracts visitors. </p>
<p>No place is off the tourism circuit, so tourism grows with few limits. Ironically, tourists even want to <a href="https://www.routledge.com/Last-Chance-Tourism-Adapting-Tourism-Opportunities-in-a-Changing-World/Lemelin-Dawson-Stewart/p/book/9780415618236">tour Antarctica</a> to see its pristine environment before it disappears (“last-chance tourism”). This is despite their impacts <a href="https://www.theguardian.com/world/2016/jun/26/antarctica-tourism-regulations-cruises-field-trips">contributing</a> to global warming and threatening this last wild place.</p>
<p>It is difficult to get a complete picture of the impacts of tourism because no-one is working to build a comprehensive view. So, insights are fragmented.</p>
<p>While we might be sceptical that UN “years” are often more rhetoric than real, we can nonetheless seize the opportunity to make tourism more sustainable.</p>
<h2>How can tourism be made more sustainable?</h2>
<p>Tourism can be made more sustainable through several achievable measures. Some look to <a href="https://www.businessinsider.com.au/boeing-jetblue-invest-zunum-electric-jet-startup-2017-4?r=US&IR=T">technological solutions</a> so we can continue business as usual. Others highlight conscious consumerism and ideas like <a href="http://www.slowmovement.com/slow_travel.php">slow travel</a>.</p>
<p>But in a world in which growing populations with endless consumer demands are pitted against a fragile environment, we require more concerted effort. </p>
<p>1) <strong>Governments</strong> must implement policies that foster sustainable development by overcoming the growth fetish. Tourism then should be developed only within sustainable development parameters. Governments must tackle the environmental limits to growth and climate change challenges we confront. Tourism development requires integrated planning. So, we need the government tourism authorities – such as Tourism Australia or state tourism commissions – focused equally on integrated planning as the marketing they currently emphasise.</p>
<p>2) <strong>Consumers</strong> should be educated for responsible travel choices. For example, few realise that all-inclusive resorts result in economic benefits from tourism leaking out of the host economy back to the home economies of the big multinationals and corporations that often own such resorts (think Club Med). Civics education in schools could educate for responsible travel.</p>
<p>3) <strong>Local communities</strong>, often treated as only as one stakeholder among the many, must have a right to participate in tourism decision-making and have a say on if and how their communities become tourism destinations.</p>
<p>4) <strong>Workers of tourism</strong> must have <a href="https://www.tourismconcern.org.uk/tag/worker-rights/">their rights</a> respected and given decent conditions. Tourism should not be allowed to continue as a low-wage and precarious source of employment.</p>
<p>5) <strong>The tourism industry</strong> needs to assume greater responsibility, submitting to local tax regimes and regulations so its presence builds thriving communities, rather than undermining them. This is increasingly essential as a social license to operate. The industry should also educate its clients on responsible tourism.</p>
<p>6) <strong>Non-governmental organisations</strong> are essential for reporting on the abuses of tourism, including land grabs, human rights abuses, community opposition and corruption.</p>
<p>Harnessing these essential stakeholders in a rigorous agenda for sustainable development, rather than sustaining tourism, would make the UN’s “year” more meaningful.</p><img src="https://counter.theconversation.com/content/76018/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Freya Higgins-Desbiolles is affiliated with the Centre for Tourism and Leisure Management, University of South Australia. She is an affiliate of Equality in Tourism, a member of the Tourism Advocacy and Action Forum, co-founder of the International Peace Tourism Commission and formerly involved in responsible tourism initiatives for Community Aid Aborad (now Oxfam Australia).</span></em></p>No place is off-limits to tourism, so the industry grows without restriction – but there are ways to curb the environmental damage it does.Freya Higgins-Desbiolles, Senior Lecturer in Tourism, University of South AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/675912017-02-16T03:20:49Z2017-02-16T03:20:49ZGalapagos giant tortoises make a comeback, thanks to innovative conservation strategies<figure><img src="https://images.theconversation.com/files/152457/original/image-20170111-4604-bbpm9i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Giant tortoise on Pinzon Island, Galapagos</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/islandconservation/5426692920/in/photolist-rLDPo1-qPLnGu-rLDLvY-qPYtte-rsrxtT-rLF1gv-rLEZAT-rLLbQa-rLL5na-rLDxV7-rLEQpg-rsqH3V-ruatxC-rubKD5-rLKmW4-rubHfN-ruapLu-rubFUw-qgx9eu-mRVMsD-mRXpFs-mJkfyT-fduYq6-e3rCZk-dVpcWt-drEmk3-d6sUx3-c9aAHQ-au6Ljz-9gxdK3-8QNhj8-8Le6jw-7Z4QnG-7Z4No9-7YUKUK-7ufSHW-731EmL-6LhXVz-6DMd4y-5JFxS1-5vtRdS-4ZAmWJ-4Ufucf-4ip6Rf-41mcXe-41m7D8-3P9hN9-2Whbnc-8onzM-7tPhE">Rory Stansbury, Island Conservation/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>The <a href="http://whc.unesco.org/en/list/1">Galapagos Islands</a> are world-famous as a laboratory of biological evolution. Some 30 percent of the plants, 80 percent of the land birds and 97 percent of the reptiles on this remote archipelago are found nowhere else on Earth. Perhaps the most striking example is the islands’ iconic giant tortoises, which often live to ages over 100 years in the wild. Multiple species of these mega-herbivores have evolved in response to conditions on the island or volcano where each lives, <a href="http://www.amnh.org/exhibitions/lonesome-george/galapagos-tortoises-and-evolution/">generating wide variation</a> in shell shape and size. </p>
<p>Over the past 200 years, hunting and invasive species reduced giant tortoise populations by an estimated 90 percent, destroying several species and pushing others to the brink of extinction, although a few populations on remote volcanoes remained abundant. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/156244/original/image-20170209-8637-1vrlh2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/156244/original/image-20170209-8637-1vrlh2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=438&fit=crop&dpr=1 600w, https://images.theconversation.com/files/156244/original/image-20170209-8637-1vrlh2e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=438&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/156244/original/image-20170209-8637-1vrlh2e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=438&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/156244/original/image-20170209-8637-1vrlh2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=551&fit=crop&dpr=1 754w, https://images.theconversation.com/files/156244/original/image-20170209-8637-1vrlh2e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=551&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/156244/original/image-20170209-8637-1vrlh2e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=551&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Remains of tortoises killed by hunters, Galapagos Islands, 1903.</span>
<span class="attribution"><a class="source" href="https://www.loc.gov/resource/cph.3c24341/">R.H. Beck/Library of Congress</a></span>
</figcaption>
</figure>
<p>Now however, the tortoise dynasty is on the road to recovery, thanks to work by the <a href="http://www.galapagos.gob.ec/">Galapagos National Park Directorate</a>, with critical support from nonprofits like the <a href="http://www.galapagos.org/">Galapagos Conservancy</a> and advice from an international team of conservation scientists. </p>
<p>Together we are advancing a broad multiyear program called the <a href="http://www.galapagos.org/conservation/conservation/project-areas/ecosystem-restoration/tortoise-restoration/">Giant Tortoise Restoration Initiative</a>, overseen by Washington Tapia, Linda Cayot and myself with major collaboration from <a href="http://caccone.yale.edu/">Gisella Caccone</a> at Yale University. Using many novel strategies, the initiative helps guide the Galapagos National Park Directorate to restore viable, self-sustaining tortoise populations and recover the ecosystems in which these animals evolved.</p>
<h2>Back from the brink</h2>
<p>As many as 300,000 giant tortoises once roamed the Galapagos Islands. Whalers and colonists started collecting them for food in the 19th century. Early settlers introduced rats, pigs and goats, which preyed upon tortoises or destroyed their habitat. As a result, it was widely concluded by the 1940s that giant tortoises were headed for oblivion. </p>
<p>After the Galapagos National Park was established in 1959, park guards halted killing of tortoises for food. Next, biologists at what was then known as the <a href="http://www.darwinfoundation.org/en/">Charles Darwin Research Station</a> did the first inventory of surviving tortoises. They also initiated a program to help recover imperiled species. </p>
<p>One species, the Pinzon Island tortoise, had not produced any juveniles for over 100 years because nonnative black rats were preying on hatchlings. In 1965 park guards started methodically removing eggs from tortoise nests, rearing the offspring to “rat-proof” size in captivity and releasing them back into the wild. More than 5,000 young tortoises have been repatriated back to Pinzon Island. <a href="http://www.galapagos.org/blog/pinzon-tortoise-survey-part2/">Many are now adults</a>. This program is one of the most successful examples of “head-starting” to save a species in conservation history. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/156255/original/image-20170209-8631-1u2zgb7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/156255/original/image-20170209-8631-1u2zgb7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=467&fit=crop&dpr=1 600w, https://images.theconversation.com/files/156255/original/image-20170209-8631-1u2zgb7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=467&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/156255/original/image-20170209-8631-1u2zgb7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=467&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/156255/original/image-20170209-8631-1u2zgb7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=587&fit=crop&dpr=1 754w, https://images.theconversation.com/files/156255/original/image-20170209-8631-1u2zgb7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=587&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/156255/original/image-20170209-8631-1u2zgb7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=587&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Gal%C3%A1pagos_Islands#/media/File:Galapagos-satellite-esislandnames.jpg">Storpilot/Wikipedia</a></span>
</figcaption>
</figure>
<p>The Española tortoise, which once numbered in the thousands, had been reduced to just 15 individuals by 1960. Park guards brought those 15 into captivity, where they have produced more than 2,000 captive-raised offspring now released onto their home island. All 15 survivors are still alive and reproducing today, and the wild population numbers <a href="http://dx.doi.org/10.1371/journal.pone.0110742">more than 1,000</a>. This is one of the greatest and least-known conservation success stories of any species.</p>
<h2>Eliminating nonnative threats</h2>
<p>Over the past 150 years, goats brought to the islands by early settlers overgrazed many of the islands, turning them into dustbowls and destroying forage, shade and water sources that tortoises relied on. In 1997 the Galapagos Conservancy launched <a href="http://www.galapagos.org/conservation/conservation/project-areas/ecosystem-restoration/project-isabela/">Project Isabela</a>, the largest ecosystem restoration initiative ever carried out in a protected area. </p>
<p>Over a decade park wardens, working closely with <a href="https://www.islandconservation.org/">Island Conservation,</a> used high-tech hunting tactics, helicopter support and <a href="http://onward.nationalgeographic.com/2014/09/02/on-the-galapagos-the-betrayal-of-judas-goats/">Judas goats</a> – animals fitted with radio collars that led hunters to the last remaining herds – to <a href="http://dx.doi.org/10.1371/journal.pone.0018835">eliminate over 140,000 feral goats</a> from virtually all of the archipelago. </p>
<p>Building on <a href="http://dx.doi.org/10.2193/2007-551">lessons learned</a> from Project Isabela, the Galapagos National Park Directorate and Island Conservation then eradicated nonnative rats from Pinzón Island in 2012, enabling tortoise hatchlings to survive and complete their life cycle again <a href="http://dx.doi.org/10.1038/517271a">for the first time in a century</a>. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/156258/original/image-20170209-8655-1918fzu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/156258/original/image-20170209-8655-1918fzu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/156258/original/image-20170209-8655-1918fzu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/156258/original/image-20170209-8655-1918fzu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/156258/original/image-20170209-8655-1918fzu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/156258/original/image-20170209-8655-1918fzu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/156258/original/image-20170209-8655-1918fzu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/156258/original/image-20170209-8655-1918fzu.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">One of the first hatchlings on Pinzon Island in over a century (click to zoom).</span>
<span class="attribution"><span class="source">James Gibbs</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Restoring ecosystems with tortoises</h2>
<p>The argument for tortoise conservation has been strengthened by reconceptualizing giant tortoises as agents whose actions shape the ecosystems around them. Tortoises eat and disperse many plants as they move around – and they are more mobile than many people realize. By attaching GPS tags to tortoises, scientists with the <a href="http://www.gianttortoise.org/">Galapagos Tortoise Movement Ecology Programme</a> have learned that tortoises migrate tens of kilometers up and down volcanoes seasonally to get to new plant growth and nesting sites. </p>
<p>As they move, tortoises crush vegetation. They may be an important factor in maintaining the native savannah-like ecosystems on the islands where they live. When tortoises are scarce, we think that shrubs sprout up, crowding out many herbaceous plants <a href="http://www.galapagos.org/conservation/conservation/project-areas/ecosystem-restoration/tortoise-restoration/espanola-survey-and-monitoring/">and other animal species</a>. </p>
<p>We need data to support this theory, so we have constructed an elaborate system of “exclosures” on two islands that wall tortoises out of certain areas. By <a href="http://www.galapagos.org/blog/return-to-espanola-2016/">comparing vegetation</a> in the tortoise-free zones to conditions outside of the exclosures, we will see just how tortoises shape their ecosystems. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/156101/original/image-20170208-17320-1fh47pn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/156101/original/image-20170208-17320-1fh47pn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/156101/original/image-20170208-17320-1fh47pn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/156101/original/image-20170208-17320-1fh47pn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/156101/original/image-20170208-17320-1fh47pn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/156101/original/image-20170208-17320-1fh47pn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/156101/original/image-20170208-17320-1fh47pn.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">Building a tortoise exclosure.</span>
<span class="attribution"><span class="source">James Gibbs</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Restoring ecosystems on islands where tortoises have gone extinct requires more drastic steps. Santa Fe Island lost its endemic giant tortoises more than 150 years ago, and its ecosystems are still recovering from a scourge of goats. Park managers are attempting to restore the island using an “analog,” nonnative species – the genetically and morphologically similar Española tortoise. </p>
<p>In 2015 the Galapagos National Park Directorate <a href="https://www.youtube.com/watch?v=UdzVagISaO4">released 201 juvenile Española tortoises</a> in the interior of Santa Fe Island. They all appear to have survived their first year there, and 200 more are scheduled for release in 2017. Española tortoises are still endangered, so this strategy has the extra value of creating a reserve population of them on Santa Fe island.</p>
<p>On Pinta Island, which also has lost its endemic tortoise, park managers have <a href="https://www.youtube.com/watch?v=C1w-T0ZMcsE">released sterilized nonnative tortoises</a> to serve as “vegetation management tools” that can prepare the habitat for future introductions of reproductive tortoises. These initiatives are some of the first-ever to use analog species to jump-start plant community restoration.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/152453/original/image-20170111-4601-1s2k5u8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/152453/original/image-20170111-4601-1s2k5u8.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=396&fit=crop&dpr=1 600w, https://images.theconversation.com/files/152453/original/image-20170111-4601-1s2k5u8.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=396&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/152453/original/image-20170111-4601-1s2k5u8.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=396&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/152453/original/image-20170111-4601-1s2k5u8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/152453/original/image-20170111-4601-1s2k5u8.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/152453/original/image-20170111-4601-1s2k5u8.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=498&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Park rangers releasing juvenile giant tortoises from the Espanola Island lineage to Santa Fe Island in June 2015.</span>
<span class="attribution"><span class="source">Galapagos National Park Directorate</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Reviving lost species</h2>
<p>The endemic tortoises of Floreana Island are also considered to be extinct. But geneticists recently discovered that in a remote location on Isabela Island, tortoises evidently had been translocated from around the archipelago during the whaling era. In a major expedition in 2015, park rangers and collaborating scientists <a href="https://theconversation.com/how-we-rediscovered-extinct-giant-tortoises-in-the-galapagos-islands-and-how-to-save-them-52073">removed 32 tortoises from Isabela Island</a> with shell features similar to the extinct Pinta and Floreana species. </p>
<p>Now the geneticists are exploring the degree of interbreeding of these 32 distinct tortoises between the extinct species and native Wolf Volcano tortoises. We are hoping to find a few “pure” survivors from the extinct species. Careful and selective breeding of tortoises in captivity with significant levels of either Pinta or Floreana ancestry will follow to produce a new generation of young tortoises to be released back on Pinta and Floreana Islands and help their ecosystems recover. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/155744/original/image-20170206-27189-1srcrgc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/155744/original/image-20170206-27189-1srcrgc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=393&fit=crop&dpr=1 600w, https://images.theconversation.com/files/155744/original/image-20170206-27189-1srcrgc.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=393&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/155744/original/image-20170206-27189-1srcrgc.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=393&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/155744/original/image-20170206-27189-1srcrgc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=494&fit=crop&dpr=1 754w, https://images.theconversation.com/files/155744/original/image-20170206-27189-1srcrgc.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=494&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/155744/original/image-20170206-27189-1srcrgc.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=494&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Removing a Wolf Volcano tortoise from Isabela Island for the Floreana tortoise restoration initiative.</span>
<span class="attribution"><span class="source">Jane Braxton Little</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<h2>Converting tragedy to inspiration</h2>
<p>Lonesome George, the last known living Pinta Island giant tortoise, died in 2012 after decades in captivity. His frozen remains were transferred to the United States and taxidermied by <a href="http://www.amnh.org/explore/preserving-lonesome-george">world-class experts</a>. In mid-February Lonesome George will be returned to Galapagos once again and ensconced as the focus of a newly renovated park visitation center. Some 150,000 visitors each year will learn the complex but ultimately encouraging story of giant tortoise conservation, and a beloved family member will rest back at home again.</p><img src="https://counter.theconversation.com/content/67591/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>James P. Gibbs works for the State University of New York's College of Environmental Science and Forestry and serves in a remunerated position as Adjunct Scientist for the Galapagos Conservancy. He is also a research collaborator with the Giant Tortoise Movement Ecology Programme. He receives funding from the National Science Foundation (DEB 1258062) and the Galapagos Conservancy for the work described here. </span></em></p>The Galapagos Islands’ giant tortoises are one of the world’s best examples of evolution. Scientists are pioneering new conservation strategies to save them from extinction and restore their habitat.James P. Gibbs, Professor of Vertebrate Conservation Biology and Director of the Roosevelt Wild Life Station, State University of New York College of Environmental Science and ForestryLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/685142016-11-09T13:53:23Z2016-11-09T13:53:23ZIn defence of racer snakes – the demons of Planet Earth II (they’re only after a meal)<figure><img src="https://images.theconversation.com/files/145222/original/image-20161109-19089-1mz6jky.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">BBC</span></span></figcaption></figure><p>It’s the stuff of nightmares: a rockface that comes alive with a writhing mass of snapping serpents seemingly hellbent on working together to capture and consume a defenceless young marine iguana. This jaw-dropping scene aired as part of the new series of the BBC’s flagship natural history programme, <a href="http://www.bbc.co.uk/iplayer/episode/p048sflc/planet-earth-ii-1-islands">Planet Earth II</a>, and seems to have <a href="https://twitter.com/i/moments/795865871226810368">captured the imagination of millions</a>.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"795386281257816064"}"></div></p>
<p>Filmed on <a href="http://www.galapagos.org/about_galapagos/about-galapagos/the-islands/fernandina/">Fernandina Island</a> in the Galápagos, the Galápagos Racer (<em>Philodryas biserialis</em>) is a slim, fast-moving, mildly venomous snake that reaches lengths of up to 120cm. They were filmed during their best feeding opportunity of the year, as young iguanas are born and make a dash for the safety of the higher rocks above. Snake eyesight has evolved to quickly detect movement – and once they spot a target, their reactions can appear highly aggressive and relentless in pursuit.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/B3OjfK0t1XM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>It’s all too easy to demonise the snake, and for years that’s exactly what the media has encouraged. Reports involving snakes are commonly misrepresented or deliberately sensationalised. Snakes are often portrayed as slimy, cold, angry sticks with teeth rather than anything resembling a living, breathing creature. This of course does little to alleviate public <a href="http://www.fearof.net/fear-of-snakes-phobia-ophidiophobia/">ophidiophobia</a>, an irrational fear of snakes.</p>
<p>In fact, my first break as a wildlife presenter came about following a phone call from the BBC Natural History department regarding snakes, having seen me deliver a talk for the British Association of Science at Cardiff University.</p>
<p>“We’d love to shoot a documentary about adders with you,” the voice on the other end of the phone exclaimed. “We especially want to see the fangs, and the venom … just how much venom can we see from milking an adder?”</p>
<p>Taking a deep breath, I clarified through gritted teeth that Britain’s only venomous snake was both shy and reclusive and not at all aggressive. It was a delicate snake that could easily be injured, and it would be unethical to undertake such an exercise just for the camera. A documentary of that calibre would present adders in a poor light, and it was not a project I would want to be part of.</p>
<p>“Okay,” the voice replied, seemingly without hearing a word I had just uttered. “Do you know anyone else that would be interested?”</p>
<p>I remember thinking that that would be the last chance I’d ever have to work for the BBC, but also feeling that I’d made the right decision. A couple of days later, though, I received another call telling me that the documentary had been poorly thought out and that a decision had been made to cancel the production. As you can imagine, I was relieved. And rather than hinder my career, my stand attracted BBC producers with better judgement, and eventually led to me presenting my own primetime BBC One wildlife series, <a href="http://www.bbc.co.uk/programmes/b040454w">Rhys Jones’s Wildlife Patrol</a>. </p>
<p>But while it worked out well for me in the end, the same cannot be said for the racer snake, which has already been roundly and colourfully attacked. Rather than capturing a coordinated attack from snakes hunting as a pack, the clip from Planet Earth II actually shows a number of snakes acting individually, on instinct. The time of year when these iguanas hatch is for these snakes the equivalent of Black Friday bargain hunting – it’s every snake for itself, because if they miss out here, they’ll go hungry. Collectively, the actions of these snakes can appear terrifying, but once a snake eats it loses its desire to hunt again.</p>
<p>Unlike mammals, snakes don’t chew their food and have no appendages with which to carve up a share of their quarry with their kin. Evolution has instead led them to consume their prey whole, digesting bones and all. As <a href="https://www.britannica.com/science/ectotherm">ectothermic</a> – or cold-blooded – animals, reptiles only require around a tenth of the food intake of a similarly-sized mammal to survive. Once prey is consumed, the snake may not eat again for several weeks. </p>
<p>It is perhaps because snakes’ eating habits, appearance and movement is alien to us that we fear them. After all, we are most often afraid of the things we don’t understand and struggle to anticipate. Throughout history we’ve presented the snake as a symbol of evil and danger. No surprise then to <a href="http://metro.co.uk/2016/11/07/this-utterly-brutal-iguanasnake-battle-on-planet-earth-2-had-everybody-screaming-at-their-tvs-6241162/">witness the relief</a> felt when the little iguana slipped through the snakes’ constricting coils and escaped to safety. But I suspect very few people gave a second thought to the plight of the snakes left hungry on the beach.</p><img src="https://counter.theconversation.com/content/68514/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rhys Jones 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>TV audiences cheered on the iguanas’ escape, but won’t somebody think of the poor snakes?Rhys Jones, Lecturer in Biology, Cardiff UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/606972016-06-09T20:10:15Z2016-06-09T20:10:15ZDoes tourism really suffer at sites listed as World Heritage In Danger?<figure><img src="https://images.theconversation.com/files/125856/original/image-20160609-3475-1fdwyqn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Visits to Belize's reefs have been climbing, despite them being listed as World Heritage in Danger since 2009.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File%3ABelize_Barrier_Reef%2C_from_Ambergris_Caye.jpg">Elizabeth Albert/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>In 2014, <a href="http://www.gbrmpa.gov.au/visit-the-reef/visitor-contributions/gbr_visitation/numbers/tourist-visits-to-the-entire-marine-park">1.88 million tourists</a> visited the Great Barrier Reef, bringing an estimated <a href="https://www.environment.gov.au/sustainability/publications/economic-contribution-great-barrier-reef-march-2013">A$5.17 billion</a> into Australia’s economy and helping to employ some <a href="https://www.environment.gov.au/sustainability/publications/economic-contribution-great-barrier-reef-march-2013">64,300 tourism workers</a>.</p>
<p>With those numbers, it’s easy to see how threats to the Reef’s future, such as the recent <a href="https://theconversation.com/au/topics/2016-coral-bleaching-event">mass bleaching event</a>, are confronting for the tourism sector. Perhaps unsurprisingly, many tourism operators have chosen to remain quiet about their concerns or <a href="http://www.4ca.com.au/news/local-news/51369-tourism-industry-pushes-back-against-bleaching-claims">downplay the issue</a>, fearful that mentioning the threats would turn tourists away. </p>
<p>The federal environment department evidently felt the same way, judging by its request that all references to Australian World Heritage sites, including the Reef, be <a href="http://www.theguardian.com/environment/planet-oz/2016/may/30/australias-censorship-of-unesco-climate-report-is-like-a-shakespearean-tragedy">removed</a> from a UNESCO <a href="http://whc.unesco.org/en/activities/883/">report on climate change and World Heritage tourism</a>.</p>
<p>But does this reasoning stack up? Three other famous tourist destinations have also been in the spotlight of the World Heritage Committee, with little indication that this has turned visitors away.</p>
<p><strong><a href="http://whc.unesco.org/en/list/1">Galápagos Islands</a></strong></p>
<p>Galápagos was <a href="http://whc.unesco.org/en/decisions/1416">listed as World Heritage In Danger from 2007-10</a>, primarily because of the impacts of tourism, and was taken off again once the World Heritage Committee was satisfied that its concerns had been addressed. The area is now facing other <a href="http://whc.unesco.org/en/decisions/6069">issues</a>, including biosecurity, sustainable development and fishing, but Galápagos tourism continues to grow, as shown in the graph below, with almost <a href="http://www.galapagos.org/newsroom/galapagos-tourism-growth-2015/">225,000 visits</a> in 2015.</p>
<p><strong><a href="http://whc.unesco.org/en/list/76">Everglades National Park</a></strong></p>
<p>Everglades National Park was listed as World Heritage In Danger in 1993, and <a href="http://whc.unesco.org/en/danger/">remains on the list today</a> (although it was briefly taken off in 2008 before being reinstated in 2010). Annual visitor numbers have fluctuated around the 1 million mark, although official figures count only those who pass through the park’s entrance stations, and many more people enter through the miles of surrounding waters.</p>
<p><strong><a href="http://whc.unesco.org/en/list/764">Belize Barrier Reef Reserve System</a></strong></p>
<p>Belize’s reefs have been on the <a href="http://whc.unesco.org/en/danger/">World Heritage In Danger list</a> since 2009, due to a range of issues including invasive species, oil and gas exploitation, and inappropriate visitor accommodation and associated infrastructure. Tourist numbers recently reached a high of 968,131 cruise arrivals in 2014.</p>
<hr>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/125858/original/image-20160609-3477-186ggrr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/125858/original/image-20160609-3477-186ggrr.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=546&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125858/original/image-20160609-3477-186ggrr.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=546&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125858/original/image-20160609-3477-186ggrr.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=546&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125858/original/image-20160609-3477-186ggrr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=686&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125858/original/image-20160609-3477-186ggrr.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=686&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125858/original/image-20160609-3477-186ggrr.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=686&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="source" href="http://whc.unesco.org/en/danger/">Data compiled by author</a></span>
</figcaption>
</figure>
<hr>
<h2>What can we learn from these numbers?</h2>
<p>The first thing to note is that the Great Barrier Reef has, to date, avoided being listed as World Heritage In Danger, thanks to last year’s <a href="https://theconversation.com/the-barrier-reef-is-not-listed-as-in-danger-but-the-threats-remain-42548">successful campaign by the federal and Queensland governments</a> – although there is no guarantee it will not be added in the future. </p>
<p>But what do the statistics above tell us about what happens to tourism numbers when World Heritage sites are officially listed as “In Danger”?</p>
<p>Galápagos suffered a very slight downturn in tourism after it was added to the In Danger list in 2007, but since then tourism has continued to grow, and today numbers are higher than they have ever been.</p>
<p>In Belize, tourism has fluctuated since the site was listed as World Heritage In Danger in 2009, but here too, tourist numbers today are at <a href="https://www.google.com.au/search?q=belize+tourism+statistics&espv=2&biw=1366&bih=653&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwjvhr_9q5rNAhWEmZQKHYJbAKsQsAQISA&dpr=1">record highs</a> despite the fact that these reefs remain on the In Danger list.</p>
<p>Finally to the Everglades, which has been placed on the World Heritage In Danger list twice – both times at the <a href="http://whc.unesco.org/en/decisions/4137">request of the US government</a>. This shows that, while sites can be taken off the list if their prospects improve, not all governments think that an In Danger listing is itself a bad thing. Certainly, Everglades tourism numbers do not seem to have suffered since it was placed back on the list in 2010.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/125854/original/image-20160609-3475-ab7cli.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/125854/original/image-20160609-3475-ab7cli.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/125854/original/image-20160609-3475-ab7cli.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125854/original/image-20160609-3475-ab7cli.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125854/original/image-20160609-3475-ab7cli.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125854/original/image-20160609-3475-ab7cli.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125854/original/image-20160609-3475-ab7cli.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125854/original/image-20160609-3475-ab7cli.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Airboating in the Everglades: still a popular jaunt.</span>
<span class="attribution"><span class="source">chensiyuan/Wikimedia Commons</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Why did the United States lobby to have the Everglades officially described as In Danger, while Australia fought to keep the Great Barrier Reef off the list? As <a href="https://www.nps.gov/ever/learn/nature/sfnrccmitchell.htm">Carol Mitchell</a>, Deputy Director of the South Florida Natural Sciences Center, has explained, the In Danger listing makes it clear to the national and international community that the Everglades still needs attention. Mitchell wrote to me:</p>
<blockquote>
<p>It helps to keep some external pressure on both the federal and Florida state governments in their efforts to restore the park … both governments are strongly committed to Everglades restoration; nevertheless … the ability to call upon important, very visible international designations … does help to maintain those commitments.</p>
</blockquote>
<h2>Tourists already know the Great Barrier Reef is threatened</h2>
<p>Despite what the Australian government and many tourism operators would like to believe, the threats to the Great Barrier Reef are already widely known, because they have drawn <a href="http://www.nytimes.com/2016/05/30/world/australia/bleaching-coral-death-great-barrier-reef.html?_r=0">global media</a> attention.</p>
<p>How this translates into the <a href="https://theconversation.com/climate-change-tourism-and-the-great-barrier-reef-what-we-know-60108">perceptions of prospective tourists</a> in not yet clear. But the indications from elsewhere around the world is that In Danger listing does not have a significant impact on tourism, and presumably we could say the same about inclusion in documents such as UNESCO’s tourism report.</p>
<p>Many other factors are far more important to tourists, including the economic situation, access, weather events, service quality and, importantly, a site’s relative quality compared to alternative destinations.</p>
<p>Tourism operators are increasingly recognising that the Great Barrier Reef faces <a href="https://theconversation.com/au/topics/great-barrier-reef-threats-series">myriad threats</a>, and that its outlook is poor. Many people agree with Tony Fontes, a dive operator from the Whitsunday Islands, who <a href="https://theconversation.com/the-barrier-reef-is-not-listed-as-in-danger-but-the-threats-remain-42548">previously told me</a> that an In Danger listing “might actually be the catalyst to ensure the GBR is properly protected”.</p>
<p>Recently, other GBR tourism operators have <a href="http://www.couriermail.com.au/news/queensland/tourism-operator-says-its-time-for-industry-to-admit-great-barrier-reef-has-problems/news-story/6ff52a2d24fc4973c8f8c3e6e51408b4">spoken out</a> about the worst crisis ever faced by the GBR, with some <a href="http://thetourismnews.com.au/media-and-communications/reef-recovery-hinges-on-rogue-tourism-operators/">200 businesses and individuals</a> pleading with the government to tackle climate change and the many other threats that together threaten the Reef’s future.</p>
<h2>What needs to be done?</h2>
<p>Ignoring the indisputable fact that the Great Barrier Reef ecosystem is under unprecedented pressures will help neither tourism nor the environment in the long term. A more effective strategy would be for the relevant agencies and operators alike to create realistic expectations, and responsibly inform tourists of the real situation.</p>
<p>University of Queensland professor <a href="https://theconversation.com/profiles/ove-hoegh-guldberg-2012">Ove Hoegh-Guldberg</a> has <a href="https://www.thesaturdaypaper.com.au/news/politics/2016/06/04/the-real-story-the-great-barrier-reef/14649624003332">summed up the situation</a>:</p>
<blockquote>
<p>The reef is in dire trouble, but it’s decades away before it’s no longer worth visiting. That’s the truth. But unless we wake up and deal with climate change sincerely and deeply then we really will have a Great Barrier Reef not worth visiting.</p>
</blockquote>
<p>Australia has an <a href="http://whc.unesco.org/archive/convention-en.pdf">international obligation</a> to safeguard the Great Barrier Reef for future generations. As a relatively rich country, Australia needs to show global leadership, but this will require <a href="http://www.theguardian.com/environment/2016/may/19/great-barrier-reef-needs-10bn-for-chance-of-survival-scientists-say">more government assistance</a>, leadership from industry and, crucially, <a href="http://www.9news.com.au/national/2016/06/06/00/09/new-ad-pitches-reef-for-election-spotlight">widespread public support</a> for action. If reef tourists from around the world know the real situation, they might be able to help too.</p><img src="https://counter.theconversation.com/content/60697/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jon C. Day does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Australia’s government has lobbied hard to avoid the Great Barrier Reef being described internationally as being in danger. But that publicity wouldn’t necessarily hit tourism that hard anyway.Jon C. Day, PhD candidate, ARC Centre of Excellence for Coral Reef Studies, James Cook UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/520732016-01-07T19:21:10Z2016-01-07T19:21:10ZHow we rediscovered ‘extinct’ giant tortoises in the Galápagos Islands – and how to save them<figure><img src="https://images.theconversation.com/files/107453/original/image-20160106-14955-1uscslj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">One of the several precious giant tortoises recently found on Volcano Wolf, Galápagos Islands</span> <span class="attribution"><span class="source">Luciano Beheregaray</span></span></figcaption></figure><p>The Galápagos Islands, 1,000 kilometres off the coast of South America, are probably most famous as the place that inspired Charles Darwin’s <a href="https://theconversation.com/explainer-theory-of-evolution-2276">theory of evolution</a>. They are home to an extraordinary array of wildlife, including giant Galápagos tortoises, the world’s largest land-living cold-blooded animals. </p>
<p>The tortoises once thrived in the archipelago. There were originally 15 species that <a href="http://www.pnas.org/content/101/17/6514.full">evolved as the islands formed volcanically</a>. However, since the arrival of people four species have become extinct. </p>
<p>A few weeks ago we returned from an expedition to the islands in search of two of these extinct species of tortoises. It may sound like a fool’s errand, but our expedition was a success. </p>
<p>Here’s how we did it. </p>
<h2>Tortoises under threat</h2>
<p>The Galápagos Islands were colonised in the late 1800s. A combination of poaching by whalers and pirates, and introduced pests competing for food and eating eggs and hatchlings, led to tortoises being exterminated on some islands, and dramatically reduced on others. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/107482/original/image-20160107-14966-93jac6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/107482/original/image-20160107-14966-93jac6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/107482/original/image-20160107-14966-93jac6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=343&fit=crop&dpr=1 600w, https://images.theconversation.com/files/107482/original/image-20160107-14966-93jac6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=343&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/107482/original/image-20160107-14966-93jac6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=343&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/107482/original/image-20160107-14966-93jac6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=431&fit=crop&dpr=1 754w, https://images.theconversation.com/files/107482/original/image-20160107-14966-93jac6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=431&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/107482/original/image-20160107-14966-93jac6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=431&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Lonesome George, photographed before his death at the age of about 100.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/putneymark/1351695967/in/photolist-34rN7T-5bSaiw-9tj9ht-9tj94z-ddSFnF-5ZkkAG-5ZEWRd-6uBcng-2VoC8b-fSktL5-7qthop-5ZAK66-2VjeSp-frYxAd-oRuePR-6bwgpi-amMf7L-5ZEXzy-4z5wrn-4z9Kkf-4z9NVY-4z5AY2-4z9Q9d-4z9SCb-4z9LEf-4z5BRP-4z5uFp-4z5Bhr-4z5wVp-4z9LTQ-5ZEXjG-7pBkcK-djLaSB-nqnCJ-94aMU7-5Y6B6q-9tn6A7-au9qVd-au6Ljz-5Y2kq8-amQy7m-cm7hp3-cYsUQW-4z5uUX-4z5yTe-4z9TEf-4z9PtS-4z5vv8-4z9R97-4z9Pzq">Flickr/putneymark</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Darwin wrote about the harvesting of the species of tortoise found only on Floreana Island (<em><a href="http://www.iucnredlist.org/details/9023/0">Chelonoidis elephantopus</a></em>), which was exterminated within 15 years of his visit to the Galápagos in 1835. </p>
<p>The tortoise found only on Pinta Island (<a href="http://www.iucnredlist.org/sotdfiles/chelonoidis-(nigra)-abingdonii.pdf"><em>Chelonoidis abingdoni</em></a>) went formally extinct in 2012, when its last representative, a male held in captivity and nicknamed <a href="http://www.bbc.com/news/world-18574279">Lonesome George, died</a>. He was a major <a href="http://www.smithsonianmag.com/travel/lonesome-george-last-tortoise-his-kind-posthumous-display-nyc-180952833/?no-ist">conservation icon</a> and at one point considered by Guinness World Records as the world’s <a href="http://www.guinnessworldrecords.com/world-records/most-endangered-animal/">rarest living creature</a>.</p>
<figure>
<iframe src="https://www.google.com/maps/d/u/0/embed?mid=zXUWIAKxCpHk.kJdpTkVYSjfk" width="100%" height="480"></iframe>
<figcaption>The Galápagos Islands, showing locations mentioned in this story.</figcaption>
</figure>
<h2>Finding extinct tortoises</h2>
<p>Ten years ago our genetic <a href="http://mscg.yale.edu/">research program</a> made a very surprising discovery. Some tortoises on Volcano Wolf, on Isabela Island, didn’t match others normally found on the volcano (<em>Chelonoidis becki</em>). Instead, their DNA matched that of the extinct species from <a href="http://www.pnas.org/content/early/2008/09/19/0805340105.abstract">Floreana</a> and <a href="http://www.nature.com/news/2007/070430/full/news070430-1.html">Pinta</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/106589/original/image-20151218-8065-1rpuvvf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/106589/original/image-20151218-8065-1rpuvvf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/106589/original/image-20151218-8065-1rpuvvf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=200&fit=crop&dpr=1 600w, https://images.theconversation.com/files/106589/original/image-20151218-8065-1rpuvvf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=200&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/106589/original/image-20151218-8065-1rpuvvf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=200&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/106589/original/image-20151218-8065-1rpuvvf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=252&fit=crop&dpr=1 754w, https://images.theconversation.com/files/106589/original/image-20151218-8065-1rpuvvf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=252&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/106589/original/image-20151218-8065-1rpuvvf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=252&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Volcano Wolf – the highest point of the Galápagos Islands.</span>
<span class="attribution"><span class="source">Luciano Beheregaray</span></span>
</figcaption>
</figure>
<p>These exciting discoveries led to an expedition on Volcano Wolf in 2008, where we tagged and sampled over 1,600 tortoises. DNA analyses revealed an astonishingly large number of tortoises with mixed genetic ancestry in this sample: 89 with DNA from Floreana and 17 with DNA from Pinta.</p>
<p>How was this possible?</p>
<p>It is likely that people have been moving tortoises around the islands. Old logbooks from the whaling industry indicate that, in order to lighten the burden of their ships, whalers and pirates dropped large numbers of tortoises in Banks Bay, near Volcano Wolf. </p>
<p>These animals were collected from lower altitudes islands (Floreana and Pinta) during centuries of exploitation by whalers and pirates, who made the archipelago a regular stop-off for their crews to stock up on these <a href="https://www.newscientist.com/article/mg19426071-300-galapagos-tortoises-untangling-the-evolutionary-threads/">handy living larders</a>. </p>
<p>Many of these tortoises made it to shore and eventually mated with the native Volcano Wolf species, producing hybrids that still maintain the distinctive saddleback shell found in the species from Floreana and Pinta. These hybrids include animals whose parents represent purebred individuals of the two extinct species.</p>
<h2>An arduous expedition</h2>
<p>Our recent expedition was aimed at finding the animals with a high proportion of ancestors from Floreana or Pinta. </p>
<p>It was ambitious, logistically complex, and very strenuous.</p>
<p>Our team of park rangers, scientists, and veterinarians from 10 countries were divided in nine groups of three to four people each. The daily mission included patrolling large areas of unstable razor-sharp lava fields and of spiny thick vegetation across Volcano Wolf, the tallest of the Galápagos. Added to this ordeal were the frequent encounters with wasps, the equatorial heat, and an El Niño induced six-day period of non-stop rain.</p>
<p>When one of the target tortoises was found, we would contact our mother ship by radio and clear the vegetation of the volcano slopes to make room for the cargo net of our expedition’s helicopter. The precious tortoise would then be moved into the net and airlifted to the ship, which was anchored in Banks Bay.</p>
<p>Our teams discovered more than 1,300 tortoises, including nearly 200 that potentially have mixed ancestry from Floreana or Pinta. We airlifted 32 of them to the ship and then to the captive breeding facility of the Galápagos National Park on the island of Santa Cruz. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/106594/original/image-20151218-8068-1k4c9k7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/106594/original/image-20151218-8068-1k4c9k7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=383&fit=crop&dpr=1 600w, https://images.theconversation.com/files/106594/original/image-20151218-8068-1k4c9k7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=383&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/106594/original/image-20151218-8068-1k4c9k7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=383&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/106594/original/image-20151218-8068-1k4c9k7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=481&fit=crop&dpr=1 754w, https://images.theconversation.com/files/106594/original/image-20151218-8068-1k4c9k7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=481&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/106594/original/image-20151218-8068-1k4c9k7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=481&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A giant Galápagos tortoise with ancestry of an extinct species being airlifted to our ship.</span>
<span class="attribution"><span class="source">Elizabeth Hunter</span></span>
</figcaption>
</figure>
<p>Included in the 32 were four females with Floreana genes and one male and one female from Pinta that were tagged and analysed in 2008.</p>
<h2>Reintroducing ‘extinct’ tortoises</h2>
<p>The DNA of these tortoises will be analysed to inform the best breeding strategy. We want to restore as much as possible the genes originally found on Floreana and Pinta.</p>
<p>The captive-born offspring of the two extinct species are expected to be released in their native islands within the next five to ten years.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/106595/original/image-20151218-8081-13q58io.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/106595/original/image-20151218-8081-13q58io.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=385&fit=crop&dpr=1 600w, https://images.theconversation.com/files/106595/original/image-20151218-8081-13q58io.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=385&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/106595/original/image-20151218-8081-13q58io.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=385&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/106595/original/image-20151218-8081-13q58io.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=484&fit=crop&dpr=1 754w, https://images.theconversation.com/files/106595/original/image-20151218-8081-13q58io.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=484&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/106595/original/image-20151218-8081-13q58io.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=484&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Giant tortoises relocated by our expedition from the Volcano Wolf, Isabela Island, to the captive breeding program of the Galápagos National Park, Santa Cruz Island.</span>
<span class="attribution"><span class="source">Joe Flanagan</span></span>
</figcaption>
</figure>
<p>Reintroduction of these tortoises to the islands where they evolved, together with large-scale habitat restoration efforts, is essential for the <a href="http://www.galapagos.org/conservation/conservation/project-areas/ecosystem-restoration/tortoise-restoration/">restoration of the island ecosystems</a>. These long-lived large herbivores act as <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0110742">“ecosystem engineers”</a>, altering the habitat they live in to the benefit of other species. </p>
<p>Wouldn’t low genetic diversity hinder the long-term persistence of reintroduced populations?</p>
<p>This is a logical concern for reintroduction programs that rely on a small number of captive breeders. However, giant Galápagos tortoises can bounce back from major demographic crashes and respond well to reintroduction programs. </p>
<p>For instance, the Volcano Alcedo tortoise population, arguably the largest in the Galápagos, is derived from a single female lineage thought to have <a href="http://www.nature.com/news/2003/031003/full/news03029-11.html">survived a catastrophic volcano</a> eruption in pre-historical times. </p>
<p>The reintroduction of over 1,500 captive-born offspring of the species once found on Española Island is another success story. The repatriated Española population, all derived from 15 captive breeders, now <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0110742">seems well-established</a>.</p>
<p>Bringing back the Floreana and Pinta species from extinction, something inconceivable not long ago, is now a possibility. Its appeal is further increased by the fact that our expedition found that many more tortoises with genes from Floreana and Pinta still wander on the slopes of the Volcano Wolf. Adding them to breeding programs will boost the genetic diversity in the released individuals and calls for a new expedition soon to come. </p>
<p>We anticipate arduous but rewarding times ahead for giant tortoise conservation biologists.</p><img src="https://counter.theconversation.com/content/52073/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Luciano Beheregaray receives funding from the Australian Research Council.</span></em></p><p class="fine-print"><em><span>Adalgisa 'Gisella' Caccone receives funding from the Galápagos Conservancy and National Geographic Society for this research</span></em></p>When 100-year-old giant tortoise Lonesome George died in 2012, the world thought his species was lost forever. We went to the Galápagos Islands looking for ‘extinct’ tortoises – and we found them.Luciano Beheregaray, Professor in Biodiversity Genetics and ARC Future Fellow, Flinders UniversityAdalgisa 'Gisella' Caccone, Senior Research Scientist and Lecturer, Department of Ecology & Evolutionary Biology, Yale UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/380392015-04-02T23:05:24Z2015-04-02T23:05:24ZDarwin’s finches highlight the unity of all life<figure><img src="https://images.theconversation.com/files/76702/original/image-20150401-1263-1i5792k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The discovery of the genes that influence the beak shape in the famous Galapagos finches highlight the underlying unity of all life.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/krawczuk/9325718688/in/photolist-fd5Kgf-fe2cZq-fcQih6-fd5JEL-fcQruR-4JLkif-puxawp-7Ee2y-7jr7v2-7KDWNH-537g6Z-4kYRmZ-c8kYh7-349SeW-5JKhrs-9PGC5R-c8kY9Y-5JFcBX-4JLkBA-kTHWp-4kQ6he-8uBv9m-c8mpaJ-c8mDiC-4U3gSD-4YGiUc-8uypt2-4JLkqd-a1zmFQ-6Eyb1N-9wrXAb-3fzbPP-3fBzga-4YL9Pj-3fFRKS-3jMdGN-a1ziyL-c8mASf-c8mDUq-e292kq-c8moQG-c8mCcG-c8mEwf-9Siwv4-aaooCy-3fA78A-a9foVJ-a9cz5t-a9fnjA-a9foBd">Paul Krawczuk/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>When Charles Darwin visited the Galapagos Islands in October 1835, he and his ship-mates on board HMS Beagle collected specimens of birds, including finches and mockingbirds, from various islands of the archipelago.</p>
<p>At the time, Darwin took little interest in the quaint finches, making only a one-word mention of them in his <a href="http://darwin-online.org.uk/content/frameset?itemID=F1925&viewtype=text&pageseq=1">diary</a>. As painstakingly shown by <a href="http://www.sulloway.org/Finches.pdf">Frank Sulloway</a> and more recently by <a href="http://darwin-online.org.uk/people/2012,%20van%20Wyhe,%20Where%20do%20Darwin's%20finches%20come%20from.pdf">John Van Whye</a>, it wasn’t until two years later that the finches sparked Darwin’s interest.</p>
<p>By then he had received feedback from the leading taxonomist of the time, John Gould, that the samples comprised 14 distinct species, none of which had been previously described! Gould also <a href="http://darwin-online.org.uk/content/frameset?pageseq=1&itemID=A88&viewtype=side">noted</a> that their “principal peculiarity consisted in the bill [i.e. beak] presenting several distinct modifications of form”. </p>
<p>So intrigued was Darwin by this variation in size and shape of beaks that in the second (1845) edition of <a href="http://darwin-online.org.uk/content/frameset?itemID=F14&viewtype=text&pageseq=1">Journal of Researches</a> he included illustrations of the distinctive variation between species in the size and shape of their beaks. He added a comment that: </p>
<blockquote>
<p>Seeing this gradation and diversity of structure in one small, intimately related group of birds, one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends.</p>
</blockquote>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/76718/original/image-20150401-1253-ps26fc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/76718/original/image-20150401-1253-ps26fc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/76718/original/image-20150401-1253-ps26fc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=453&fit=crop&dpr=1 600w, https://images.theconversation.com/files/76718/original/image-20150401-1253-ps26fc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=453&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/76718/original/image-20150401-1253-ps26fc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=453&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/76718/original/image-20150401-1253-ps26fc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=569&fit=crop&dpr=1 754w, https://images.theconversation.com/files/76718/original/image-20150401-1253-ps26fc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=569&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/76718/original/image-20150401-1253-ps26fc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=569&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 famously varied beak shapes of the Galapagos finches, as illustrated in the second edition of Darwin’s Journal of Researches.</span>
<span class="attribution"><span class="source">Wikimedia</span></span>
</figcaption>
</figure>
<p>Unfortunately for Darwin, the closer he examined the available evidence on Galapagos finches, the more confusing the picture became. This was partly because the specimens available to him were not sufficiently labelled as to their island of collection. </p>
<p>Presumably, it was his doubt about the available evidence that resulted in Darwin making no mention of Galapagos finches in any edition of <a href="http://darwin-online.org.uk/contents.html#origin">Origin of Species</a>. </p>
<p>Why, then, do people now label them as “Darwin’s finches”, and why are these finches now regarded as a classical textbook example of his theory of evolution by natural selection? </p>
<h2>Paragons of evolution</h2>
<p>Despite not mentioning Galapagos finches, Darwin did make much use of evidence from other Galapagos species (especially mockingbirds) in Origin of Species. </p>
<p>As the influence of Origin of Species spread, so too did the evolutionary fame of the Galapagos Islands. Increasingly, other biologists were drawn into resolving the questions about finches that Darwin had left unanswered. </p>
<p>By the end of the 19th century, Galapagos finches were among the most studied of all birds. By the mid-20th century, there was abundant <a href="http://www.cambridge.org/au/academic/subjects/life-sciences/darwin/darwins-finches?format=PB">evidence</a> that Galapagos finches had evolved to fill the range of ecological niches available in the archipelago – a classic example of evolution by <a href="http://evolution.berkeley.edu/evosite/evo101/VIIBDiversityclades.shtml">adaptive radiation</a>. </p>
<p>Beak size and shape were key attributes in determining adaptation to the different types of food available. In the second half of the 20th century, classic research by Princeton University’s <a href="http://www.princeton.edu/eeb/people/display_person.xml?netid=prgrant">Peter</a> and <a href="http://www.princeton.edu/eeb/people/display_person.xml?netid=rgrant&display=All">Rosemary</a> Grant provided <a href="http://press.princeton.edu/titles/8486.html">evidence</a> of quite strong natural selection on beak size and shape. </p>
<h2>Under the hood</h2>
<p>New light has also been shed on the evolution of Darwin’s finches in a <a href="http://www.nature.com/nature/journal/v518/n7539/full/nature14181.html">paper</a> recently published in Nature. In this latest research, the entire genomes of 120 individual birds from all Galapagos species plus two closely related species from other genera were sequenced. </p>
<p>The work was done by a team led by Swedish geneticist <a href="http://www.imbim.uu.se/Research/+Genomics/Andersson_Leif/?languageId=1">Leif Andersson</a>, with major input from Peter and Rosemary Grant, who are still leading experts on the finches.</p>
<p>Comparison of sequence data enabled them to construct a comprehensive evolutionary tree based on variation across the entire finch genome. This has resulted in a revised taxonomy, increasing the number of species to 18. </p>
<p>The most striking feature of the genome-based tree is the evidence for matings between different populations, resulting in the occasional joining of two branches of the tree. This evidence of “horizontal” gene flow is consistent with field data on matings of finches gathered by the Grants.</p>
<p>A comparison of whole-genome sequence between two closely related groups of finches with contrasting beak shape (blunt versus pointed) identified at least 15 regions of chromosomes where the groups differ substantially in sequence. </p>
<h2>Unity of life</h2>
<p>The most striking difference between the two groups was observed in a chromosomal region containing a regulatory gene called ALX1. This gene encodes a polypeptide that switches other genes on and off by binding to their regulatory sequences. </p>
<p>Like other such genes, ALX1 is crucially involved in embryonic development. Indeed, mutations in ALX1 in <a href="http://www.omim.org/entry/613456">humans</a> and <a href="http://www.informatics.jax.org/reference/J:33716">mice</a> give rise to abnormal development of the head and face.</p>
<p>It is an extraordinary illustration of the underlying unity of all life on Earth that Leif Andersson and his colleagues have shown that the ALX1 gene also has a major effect on beak shape in finches, and that this gene has been subject to natural selection during the evolution of the Galapagos finches.</p>
<p>If Darwin were alive today, he would be astounded at the power of genomics tools such as those used in generating the results described in this paper. He would also be delighted to see such strong evidence not only in support of evolution but also in support of one of its major forces, natural selection.</p><img src="https://counter.theconversation.com/content/38039/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Frank Nicholas 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>Darwin’s finches are known to be a paragon of evolution by natural selection, but a recent genetic discovery relating to their beaks highlights the evolutionary connectedness of all life.Frank Nicholas, Emeritus Professor of Animal Genetics, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/263992014-05-08T04:36:21Z2014-05-08T04:36:21ZNo fly zone: Darwin’s finches self-fumigate (with a little help)<figure><img src="https://images.theconversation.com/files/47956/original/yy56jsvn-1399448190.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Darwin's finch nestlings are highly vulnerable to a parasitic fly – unless their folks fumigate the nest.</span> <span class="attribution"><span class="source">Sarah A. Knutie</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>When a bird species is threatened by nest parasites, you might think the logical next step is to fumigate – unsurprisingly, though, physically spraying nests (as you might spray an infested house) is disruptive, not to mention dangerous to the birds.</p>
<p>But a group of researchers have successfully fumigated nests of Darwin’s finches on the Galapagos Islands without disrupting the birds’ natural nesting habits. In fact, they used the birds’ nest-building skills to self-fumigate with cotton balls treated with a mild delouser, as reported in <a href="http://www.sciencedirect.com/science/article/pii/S0960982214003509">Cell Biology</a> this week.</p>
<p>Despite being relatively drab in appearance, Darwin’s finches have been described as the “<a href="http://books.google.com.au/books?id=fywDdCnuxQIC&printsec=frontcover&dq=Gal%C3%A1pagos:+A+Natural+History+2006&hl=en&sa=X&ei=7dxpU6iIJsSm8AXgjIHACA&ved=0CEgQ6AEwAA#v=onepage&q=Gal%C3%A1pagos%3A%20A%20Natural%20History%202006&f=false">crown jewels of ornithology</a>” owing to their rapid and observable evolution in the wild.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/47958/original/chtp4wfy-1399448412.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/47958/original/chtp4wfy-1399448412.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/47958/original/chtp4wfy-1399448412.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=628&fit=crop&dpr=1 600w, https://images.theconversation.com/files/47958/original/chtp4wfy-1399448412.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=628&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/47958/original/chtp4wfy-1399448412.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=628&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/47958/original/chtp4wfy-1399448412.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=789&fit=crop&dpr=1 754w, https://images.theconversation.com/files/47958/original/chtp4wfy-1399448412.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=789&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/47958/original/chtp4wfy-1399448412.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=789&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 male Darwin’s finch.</span>
<span class="attribution"><span class="source">Sarah A. Knutie</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>After observing different species of the birds, Charles Darwin wrote in The Voyage of the Beagle: </p>
<blockquote>
<p>One might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends.</p>
</blockquote>
<p>He theorised that one “immigrant” bird species must have flown over from the mainland and settled in areas with varying ecological conditions, and that natural selection would probably favour “different varieties in the different islands”.</p>
<h2>Survival of the fittest</h2>
<p>Darwin’s finches continue to experience intense natural selection – but recently this selection has come from an introduced fly called <a href="http://www.issg.org/database/species/ecology.asp?si=1400"><em>Philornis downsi</em></a>. This parasite is altering the appearance of Darwin’s finches and threatening their survival. </p>
<p><em>P. downsi</em> is the only ectoparasite that causes measurable fitness costs (such as slower growth, deformation and mortality) in Darwin’s finches. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/47957/original/9v69t4p5-1399448335.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/47957/original/9v69t4p5-1399448335.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/47957/original/9v69t4p5-1399448335.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=825&fit=crop&dpr=1 600w, https://images.theconversation.com/files/47957/original/9v69t4p5-1399448335.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=825&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/47957/original/9v69t4p5-1399448335.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=825&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/47957/original/9v69t4p5-1399448335.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1037&fit=crop&dpr=1 754w, https://images.theconversation.com/files/47957/original/9v69t4p5-1399448335.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1037&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/47957/original/9v69t4p5-1399448335.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1037&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 female Darwin’s finch.</span>
<span class="attribution"><span class="source">Sarah A. Knutie</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Feather mites are common in Darwin’s finches but are not known to cause fitness costs. Blood parasites have not been detected and intestinal protozoan parasites are rare. Thus, Darwin’s finch hosts are considered naïve, as they have had little (known) exposure to pathogens in general.</p>
<p>This all changed with the arrival of <em>P. downsi</em>, which is known from collections on the Galapagos Islands in 1964 but was <a href="http://www.cabdirect.org/abstracts/20013154552.html;jsessionid=148F20D49A162BCAFA1291747BFF1348">first discovered</a> in Darwin’s finch nests in 1997.</p>
<p>The fly’s name (<em>phil</em>=loves; <em>ornis</em>=birds) paints a one-sided picture of affinity: fly larvae consume the blood and tissue of nestling birds, leaving Darwin’s finches dead or deformed. </p>
<p>Over the past decade, researchers have made significant advances in understanding the biology of this new host-parasite association. </p>
<p>Each female fly mates with an average of around two males and one to six females each lay an average of five eggs per Darwin’s finch nest. Female <em>P. downsi</em> flies generally carry around 60 eggs, so the female only lays a portion of the available clutch per host nest.</p>
<p>The <em>P. downsi</em> eggs hatch into larvae after the chicks hatch. From in-nest video recordings, we know that Darwin’s finch nestlings are <a href="http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=7914056">literally being eaten alive</a> by the fly larvae. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/IALArw5bqDY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption"><em>P. downsi</em> fly lays eggs in a Darwin’s finch nest.</span></figcaption>
</figure>
<p>The first developmental stage (or “<a href="http://en.wiktionary.org/wiki/instar">instar</a>”) of the larvae feed on the inside of the nestling beak. The second and third instar larvae live in the nest base from where they feed externally on the finch nestlings. </p>
<p>The initial phase of parasitism inside the beak often leads to beak malformation in surviving adult finches, though most nestlings die in the nest. </p>
<h2>Behavioural changes</h2>
<p>Darwin’s finches are renowned for their diverse feeding behaviours. Now we are witnessing an increasing breadth in anti-parasite behaviours. </p>
<p>There is <a href="http://www.researchgate.net/publication/231794915_Video_analysis_of_hostparasite_interactions_in_nests_of_Darwins_finches">video evidence</a> that Darwin’s finch parents and chicks preen to extract larvae from nares and the nest base, consume encountered larvae in the nest, and that siblings compete to avoid being at the bottom of the nestling pile and hence in close contact with larvae that reside in the nest base. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/47959/original/tnvsxzq7-1399448563.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/47959/original/tnvsxzq7-1399448563.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/47959/original/tnvsxzq7-1399448563.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/47959/original/tnvsxzq7-1399448563.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/47959/original/tnvsxzq7-1399448563.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/47959/original/tnvsxzq7-1399448563.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/47959/original/tnvsxzq7-1399448563.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/47959/original/tnvsxzq7-1399448563.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Treated cotton wool woven into a Darwin’s finch nest.</span>
<span class="attribution"><span class="source">Sarah A. Knutie</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Nesting density also correlates with parasite intensity: Darwin’s finch nests with many close neighbours had more <em>P. downsi</em> parasites. </p>
<p>This latest study offers a new perspective for the study of anti-parasite behaviour in nesting Darwin’s finches, and the outcomes of the study provide an exciting approach for hands-on conservation management. </p>
<p>The study shows that Darwin’s finches incorporated pyrethrum-treated cotton into their nest base during nest construction, which lowered parasite intensity during the nesting phase and increased fledging success. </p>
<p>Identifying host behavioural patterns that can be harnessed for conservation outcomes is an exciting new research direction. The conservation behaviour framework identifies <a href="http://beheco.oxfordjournals.org/content/22/2/236.full">key linkages</a> between behaviour and conservation biology derived from three basic themes:</p>
<ol>
<li>anthropogenic impacts on behaviour that impact biodiversity</li>
<li>behaviour-based management</li>
<li>behavioural indicators to other processes of conservation concern.</li>
</ol>
<p>Who knows which species we can help next with similar techniques?</p><img src="https://counter.theconversation.com/content/26399/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sonia Kleindorfer 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>When a bird species is threatened by nest parasites, you might think the logical next step is to fumigate – unsurprisingly, though, physically spraying nests (as you might spray an infested house) is disruptive…Sonia Kleindorfer, Professor of Animal Behaviour, Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.