tag:theconversation.com,2011:/institutions/zoological-society-of-london-1670/articles
Zoological Society of London
2023-04-19T15:58:26Z
tag:theconversation.com,2011:article/204126
2023-04-19T15:58:26Z
2023-04-19T15:58:26Z
2030 nature targets agreed in December may already be slipping out of reach
<figure><img src="https://images.theconversation.com/files/521843/original/file-20230419-28-ltdodz.jpg?ixlib=rb-1.1.0&rect=408%2C220%2C4832%2C3268&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A plate-billed toucan, native to the humid mountain forests of the Andes in South America.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/colorful-platebilled-toucan-wild-perched-on-1122420353">Dagmara Ksandrova/Shutterstock</a></span></figcaption></figure><p>As recently as December 2022, 196 countries <a href="https://www.unep.org/news-and-stories/story/cop15-ends-landmark-biodiversity-agreement">signed an agreement</a> promising to “live in harmony with nature” by 2050 and to “halt and reverse biodiversity loss” by 2030.</p>
<p>Previous <a href="https://www.nature.com/articles/s41586-020-2705-y">research</a> has shown that coordinated action at the global scale is urgently needed to meet such goals. As conservationists, we’re also aware of a <a href="https://doi.org/10.1016/j.tree.2015.05.002">lag</a> between when environmental changes like rising temperatures are observed by scientists and when organisms respond. We wanted to find out how this “ecological lag” might affect the world’s chances of stemming the loss of nature by the end of this decade. </p>
<p>Biodiversity – that is, the variability among living things, such as the number of species in a patch of forest – is <a href="https://livingplanet.panda.org/en-GB/">declining</a> globally. Habitat loss, harvesting, climate change, pollution and invasive species are the major <a href="https://www.science.org/doi/10.1126/sciadv.abm9982">driving forces</a> behind this ecological reorganisation. For example, species found on mountains are moving <a href="https://www.nature.com/articles/nature01286">upslope</a> where it is cooler to counteract the effects of higher temperatures in their historical distribution.</p>
<figure class="align-center ">
<img alt="A small rodent on a mountain." src="https://images.theconversation.com/files/521841/original/file-20230419-18-1unpce.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/521841/original/file-20230419-18-1unpce.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=419&fit=crop&dpr=1 600w, https://images.theconversation.com/files/521841/original/file-20230419-18-1unpce.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=419&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/521841/original/file-20230419-18-1unpce.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=419&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/521841/original/file-20230419-18-1unpce.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=526&fit=crop&dpr=1 754w, https://images.theconversation.com/files/521841/original/file-20230419-18-1unpce.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=526&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/521841/original/file-20230419-18-1unpce.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=526&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Rising temperatures are forcing alpine species to higher altitudes.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/yellow-bellied-marmot-on-ridge-near-104145308">Fremme/Shutterstock</a></span>
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<p>These pressures may have immediate consequences, like the loss of trees and habitat during deforestation. But <a href="https://link.springer.com/article/10.1007/s40823-019-00040-w">delayed effects</a>, which materialise several years or even decades after the initial environmental change, are also common.</p>
<p>Our new <a href="https://royalsocietypublishing.org/doi/10.1098/rspb.2023.0464">research</a> shows wildlife can take decades to fully reflect the environmental changes humans have already made. Some declines in excess of the 2030 target may already be locked in.</p>
<h2>Investigating ecological lags</h2>
<p>In our new study, we investigated the importance of delayed responses (lags) to climate warming and the expansion of farmland. We used <a href="http://www.livingplanetindex.org">data</a> on trends in the abundance of land-based bird and mammal populations from more than 700 species across the world.</p>
<p>We had <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.14361">previously found</a> that the speed of changes in the use of land (from forest to farmland, for instance) and climate change were useful in explaining population trends. Now we know that historical changes (those which occurred ten to 40 years previously) better explain current observable trends. For example, the population trends of small birds are best explained by how the climate was changing 13 years ago, with this delay rising to 40 years for large birds. In general, we found that larger species display longer ecological lags than smaller species. Previous <a href="https://www.science.org/doi/10.1126/science.aba1289">research</a> has also highlighted that longer-lived species respond more slowly to forest loss.</p>
<figure class="align-center ">
<img alt="An adult African elephant with its child on the savannah." src="https://images.theconversation.com/files/521837/original/file-20230419-18-yzelrz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/521837/original/file-20230419-18-yzelrz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/521837/original/file-20230419-18-yzelrz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/521837/original/file-20230419-18-yzelrz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/521837/original/file-20230419-18-yzelrz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/521837/original/file-20230419-18-yzelrz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/521837/original/file-20230419-18-yzelrz.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">An African elephant may reproduce after 25 years and live to be 70.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/elephant-her-baby-walking-through-amboseli-1726506856">Vannoy Photography/Shutterstock</a></span>
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<p>While the combination of past warming and land conversion is generally linked to population declines, these conditions appeared beneficial for small mammals in our study.</p>
<p>Our predictions of future population abundance trends suggested a mix of winners (larger birds like <a href="https://www.rspb.org.uk/birds-and-wildlife/wildlife-guides/bird-a-z/greylag-goose/">greylag geese</a> could become more numerous) and losers (medium-sized birds, like <a href="https://www.rspb.org.uk/birds-and-wildlife/wildlife-guides/bird-a-z/little-grebe/">little grebe</a>, could decline).</p>
<p>Our research suggests that these future population trends will be a product of both concurrent and past environmental conditions. Crucially, the lags of ten years or more that we identified suggest that trends up to 2030 may already be set due to their dependence on environmental change that has already happened.</p>
<p>However, all is not lost.</p>
<p>Although the ecological lags we identified in our study increase the challenge of reversing population declines by 2030, we are increasingly aware of <a href="https://www.conservationevidence.com/">what works in conservation</a>, and <a href="https://rewildingeurope.com/wildlife-comeback-report-2022/">success</a> <a href="https://conbio.onlinelibrary.wiley.com/doi/10.1111/conl.12762">stories</a> are on the rise.</p>
<p>We also assessed the effects of conservation interventions like supplementing the feeding of wildlife, granting species legal protection and creating protected areas of habitat, as well as the impact of hunting. While this kind of exploitation consistently acts as a substantial drag on population trends, management efforts and protected areas had positive impacts. Other <a href="https://doi.org/10.1016/j.oneear.2022.03.014">studies</a> have identified <a href="https://www.nature.com/articles/s41467-022-35665-9">similar</a> patterns.</p>
<figure class="align-center ">
<img alt="Large, white birds nest atop poles." src="https://images.theconversation.com/files/521842/original/file-20230419-20-62ekj3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/521842/original/file-20230419-20-62ekj3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=296&fit=crop&dpr=1 600w, https://images.theconversation.com/files/521842/original/file-20230419-20-62ekj3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=296&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/521842/original/file-20230419-20-62ekj3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=296&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/521842/original/file-20230419-20-62ekj3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=372&fit=crop&dpr=1 754w, https://images.theconversation.com/files/521842/original/file-20230419-20-62ekj3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=372&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/521842/original/file-20230419-20-62ekj3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=372&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Storks making the most of protected habitat in Extremadura, Spain.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/ciconia-storks-colony-protected-area-los-2288258717">RudiErnst/Shutterstock</a></span>
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<p>And so, preventing the overexploitation of wildlife is critical to adequately safeguarding biodiversity and the contribution of nature to human life.</p>
<h2>The outlook for nature</h2>
<p>The natural world is being dramatically reshaped by human activity.</p>
<p>Despite decades of international commitments to protect biodiversity, little progress appears to have been made.</p>
<p>The current targets are the most ambitious, and perhaps the most difficult to achieve, yet.</p>
<p>It is critical that people do not become despondent. Only with urgent action to promote the recovery of declining species can the current round of international biodiversity targets remain in our grasp.</p>
<hr>
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<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
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<hr><img src="https://counter.theconversation.com/content/204126/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard Cornford receives funding from Horizon Europe. His work has previously been funded by NERC.</span></em></p><p class="fine-print"><em><span>Fiona Spooner has received funding from NERC.</span></em></p><p class="fine-print"><em><span>Robin Freeman receives funding from Research England. The Living Planet Database used in the research is partly funded by WWF-UK.</span></em></p>
Wildlife can take years or decades to respond to environmental changes made by humans.
Richard Cornford, Research Scholar, International Institute for Applied Systems Analysis (IIASA)
Fiona Spooner, Senior Data Analyst, Our World in Data, Oxford Martin School, University of Oxford
Robin Freeman, Head of Indicators and Assessments Unit, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/200570
2023-02-23T19:20:26Z
2023-02-23T19:20:26Z
The animals and plants that only exist in captivity – and why time is running out to restore them to the wild
<figure><img src="https://images.theconversation.com/files/511958/original/file-20230223-16-qaypn5.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2400%2C1598&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Socorro dove (_Zenaida graysoni_) was confirmed to be extinct in the wild in 1981.</span> <span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Socorro_dove#/media/File:Zenaida_graysoni_-_Socorrotaube_-_Wildfarbig_-_Deutscher_Kanarien-_und_Vogelz%C3%BCchterbund_(DKB)_-_Vogelbund_-_Johann_Alexi.jpg">Johann Alexi/Freigabe-Nachweis</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>It was April in 1981 when a party of four camped for two days and nights on the forested slopes of Mount Evermann, the central peak of Socorro, a volcanic island in the Pacific some 400 kilometres southwest of Baja California, Mexico. Their fruitless search confirmed their suspicions: the <a href="https://www.iucnredlist.org/species/22690740/178409463">Socorro dove</a>, an endearingly tame bird unique to the island, had disappeared, eaten by the cats of Spanish colonists, pushed out by grazing sheep and shot from the sky by hunters.</p>
<p>But the species had not vanished. Fifty six years prior to this search, in 1925, 17 Socorro doves had been collected from the island and transported to a bird keeper in California in the US. Somehow, almost 100 years later, the descendants of these birds – the last Socorro doves on the planet – are still with us, distributed across captive facilities in Europe and North America.</p>
<p>It’s a strange liminal space: disappeared from the wild, yet not entirely extinct. And it’s one not peculiar to the Socorro dove. <a href="https://www.science.org/doi/10.1126/science.add2889">Our research</a> has confirmed that at least 33 animals and 39 plants no longer have wild populations, but survive under human care in places such as zoos, aquariums, botanic gardens and seed banks.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/511987/original/file-20230223-4215-pkp18l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A tall palm tree with feathery protrusions." src="https://images.theconversation.com/files/511987/original/file-20230223-4215-pkp18l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/511987/original/file-20230223-4215-pkp18l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/511987/original/file-20230223-4215-pkp18l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/511987/original/file-20230223-4215-pkp18l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/511987/original/file-20230223-4215-pkp18l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/511987/original/file-20230223-4215-pkp18l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/511987/original/file-20230223-4215-pkp18l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The last known Tali palm in the wild.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Corypha_taliera#/media/File:Corypha_taliera_Md_Sharif_Hossain_Sourav.jpg">Md Sharif Hossain Sourav</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<p>These species are categorised as “extinct in the wild” under <a href="https://www.iucnredlist.org/">the IUCN Red List of Threatened Species</a>, the system conservation biologists use to evaluate and communicate extinction risk. It’s a diverse set that includes the <a href="https://www.inaturalist.org/guide_taxa/1395299">manicillo</a>, a relative of the peanut only found in Bolivia; the <a href="https://www.iucnredlist.org/species/38493/10118302">Tali palm</a> originally identified from a lone specimen on the campus of Dhaka University in Bangladesh; and a number of <a href="https://www.researchgate.net/publication/231906900_From_61_species_to_five_Endemic_tree_snails_of_the_Society_Islands_fall_prey_to_an_ill-judged_biological_control_programme">tree snails</a> from the remote Society Islands in the Pacific Ocean.</p>
<p>In one sense, here is something worth celebrating: a group that has given extinction the slip. But what does the future look like for these species? Human care will not preserve them indefinitely. On the contrary, the longer they spend in captivity the more they risk becoming inbred or losing the genetic diversity that helps them resist diseases and other threats. Eventually, outright extinction looms, especially if their populations are small.</p>
<h2>Life in captivity</h2>
<p>A quirk in the red list means that conservationists don’t systematically count the numbers of seeds, plants or animals in captivity or monitor any changes in their status in the same way we do for threatened species in the wild. An extinct in the wild species numbering in the thousands is indistinguishable from one represented by a handful of individuals. We have somehow contrived to ignore the extinction risk of the very group of species for which we are most responsible.</p>
<p>Our review of this group uncovered reasons to be concerned. For the most part, it seems that these populations were founded by a tiny number of individuals and would require large populations, ideally in the thousands, to best insure against future genetic deterioration and extinctions. Unfortunately, where known, most species are held in small numbers (in the hundreds or lower), and across a small number of institutions (fewer than eight in most cases).</p>
<p>There also tends to be a lack of coordinated planning across institutions and regions where the same species is held. This is especially true for plants, where it’s not always known how many collections exist and where they are. Fortunately, there have been recent efforts by botanical gardens to share data and collaborate more closely. Seed banks are also important facilities that can store threatened plants as seeds for many decades or even centuries. But most extinct in the wild plant species can’t easily be found in online databases that might allow conservationists in different regions to work on joint recovery programmes.</p>
<p>Conservationists, and society more widely, must do better. We know that outright extinction is a real threat. Of the 95 species that have found themselves extinct in the wild or restricted to human care since 1950, 11 have since been lost forever, like the <a href="https://www.iucnredlist.org/species/178595/101749951">Christmas Island whiptail-skink</a> and the <a href="https://www.iucnredlist.org/species/37598/67372241">Saint Helena
olive</a>, a tree endemic to the island of the same name in the southern Atlantic Ocean.</p>
<h2>Return to the wild</h2>
<p>Is there hope? Perhaps surprisingly, yes. The flip side to the 11 species we’ve lost is the 12 that have been restored to the wild. These include the European bison, which, having disappeared from the wild in 1927, is now thriving in its native range in Eastern Europe and Russia, thanks to reintroduction efforts starting in the 1950s using stock from European zoos.</p>
<p>Encouragingly, more should follow: two-thirds of extinct in the wild animals and just under a quarter of extinct in the wild plants have already been released back to natural habitats. These nascent populations may not yet have reached true “wild” status by, for example, producing viable young, but this is a promising start. They show that being Extinct in the Wild needn’t be a dead end: it can be a platform for long-term restoration.</p>
<p>But if this is the aim for all extinct in the wild species and others perched on the brink, there must be a transformation in the way they are regarded and resourced. Conservationists should continue to rescue species nearing extinction and care for them in captivity. But collectively, we must also commit to revitalising the precarious populations under our care, with more individuals in more institutions. </p>
<p>Where return to the wild is a challenge, we must redouble efforts to find and mitigate threats in native habitat, or explore whether populations can be set up in new areas. Continued care of these wild populations will probably be needed.</p>
<p>Extinction looms but recovery is achievable. Conservation biologists have the tools for success, but need the support and attention of decision makers, funders and the broader public to deliver it.</p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
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<hr><img src="https://counter.theconversation.com/content/200570/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Donal Smith is affiliated with the Institute of Zoology, part of the Zoological Society of London (ZSL). ZSL operates two zoos, London Zoo and Whipsnade. The institute receives funding from Research England.</span></em></p><p class="fine-print"><em><span>Sarah Elizabeth Dalrymple is affiliated with the IUCN Species Survival Commission's Conservation Translocation Specialist Group. </span></em></p>
Surviving solely in zoos and botanic gardens are 33 animal and 39 plant species.
Donal Smith, Postdoctoral Researcher in Conservation, Zoological Society of London
Sarah Dalrymple, Senior Lecturer in Conservation Ecology, Liverpool John Moores University
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/192412
2022-11-13T05:29:42Z
2022-11-13T05:29:42Z
Climate change and wildlife: 3 studies that reveal the devastating toll on Africa’s animals
<figure><img src="https://images.theconversation.com/files/494441/original/file-20221109-10877-26vl2o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The carcass of a Grévy's zebra, an endangered species which exists only in the northern part of Kenya, where drought is ongoing.</span> <span class="attribution"><span class="source">Photo by FREDRIK LERNERYD/AFP via Getty Images</span></span></figcaption></figure><p>Climate change has produced a number of threats to wildlife. Over time, changing rainfall patterns have transformed habitats and forced animals to move. Increasing <a href="https://theconversation.com/daytime-sightings-of-elusive-aardvarks-hint-at-troubled-times-in-the-kalahari-148120">temperatures</a> are causing mass die-off events during <a href="https://theconversation.com/vulnerable-lizard-species-gets-hot-and-bothered-in-rising-temperatures-171052">heat</a> waves and making it hard for animals to find food. </p>
<p>Drought is <a href="https://theconversation.com/saving-east-africas-wildlife-from-recurring-drought-183844">recurring</a> in parts of the continent. The increased frequency means there’s little or no time to recover before the next one occurs. The wildlife in some of these regions lives alongside people who are also struggling to survive and keep their livestock alive. This puts people and wildlife into conflict as they compete for diminishing sources of water and food. </p>
<p>Climate change can also strongly influence the physiology, behaviour and breeding success of animals. </p>
<p>Academics writing for The Conversation Africa have covered some of these issues. Their articles and research sound a warning bell on the effects of climate change on wildlife. Here we share three of these important reads. </p>
<p>_</p>
<h2>Drought takes a toll on East Africa’s wildlife</h2>
<p>Over the past two decades, the Horn of Africa – specifically Ethiopia, Somalia and Kenya – has experienced more intense and frequent droughts. Drought adds to the pressure on resources like water and pasture. This makes livestock and wildlife more susceptible to malnutrition, disease, mass mortalities and competition with each other over resources. </p>
<p>Kenyan scientist and conservationist Abdullahi Ali has worked for over 15 years along the volatile Kenya-Somalia border region. He’s seen at first hand the devastating effect that these droughts have on wildlife and habitat. For instance, based on monitoring herds, he’s recorded the deaths of 30 endangered hirola (about 6% of the global population) as a direct consequence of drought over the past year. </p>
<p>Ali <a href="https://theconversation.com/saving-east-africas-wildlife-from-recurring-drought-183844">is concerned that</a> droughts are recurring. Their increased frequency means there’s little or no time to recover before the next drought. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/saving-east-africas-wildlife-from-recurring-drought-183844">Saving East Africa's wildlife from recurring drought</a>
</strong>
</em>
</p>
<hr>
<h2>Warmer temperatures, fruit trees and forest elephants</h2>
<p>Gabon is home to some of the highest densities of forest elephants. Many of them live in Lopé National Park, a 5,000km² protected area. </p>
<p>Ecological experts Katharine Abernethy, Emma Bush and Robin Whytock have <a href="https://theconversation.com/fruit-famine-is-causing-elephants-to-go-hungry-in-gabon-152757">observed</a> a significant drop in the physical condition of these elephants – an 11% decline since 2008.</p>
<p>This corresponds with a massive collapse in tree fruiting events. Elephants are much less likely than before to find ripe fruit. On average, elephants would have found ripe fruit on one in every 10 trees in the 1980s, but need to search more than 50 trees today. </p>
<p>The collapse in tree fruiting events is attributed to warmer temperatures. Lopé tree species depend on a critical drop in night-time temperatures during the long dry season to trigger flowering. In years when temperatures in the dry season did not dip below 19ºC these species produced no fruit. </p>
<p>So, even where forest elephants and other large animals are relatively well protected from threats such as hunting, global human pressures – such as the climate crisis – could affect their survival. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/fruit-famine-is-causing-elephants-to-go-hungry-in-gabon-152757">Fruit famine is causing elephants to go hungry in Gabon</a>
</strong>
</em>
</p>
<hr>
<h2>The loss of the Kalahari’s hornbills</h2>
<p>For birds in arid zones, rising temperatures pose a significant problem. They usually breed in response to rainfall, which often occurs during the hottest time of the year. And birds are mostly active during the day, when they are exposed to the sun’s heat. This is when their vital processes for reproduction take place – such as territorial defence, courtship, finding food for their young and attending the nest.</p>
<p>Ornithology expert Nicholas Pattinson <a href="https://theconversation.com/hotter-kalahari-desert-may-stop-hornbills-breeding-by-2027-183937">assessed</a> the effects of air temperature and drought on the breeding output of southern yellow-billed hornbills in southern Africa’s Kalahari Desert over a decade, from 2008 to 2019.</p>
<p>His study found that breeding output fell when air temperatures rose in the breeding season. Breeding attempts all failed when average daily maximum air temperatures exceeded 35.7°C. </p>
<p>In the Kalahari, air temperatures have already risen more than 2°C in a few decades. At this rate, by 2027, these birds will not breed at all at this site. They will quickly become locally extinct.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/hotter-kalahari-desert-may-stop-hornbills-breeding-by-2027-183937">Hotter Kalahari desert may stop hornbills breeding by 2027</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/192412/count.gif" alt="The Conversation" width="1" height="1" />
Changing habitat ranges, competition for food and water, and biological effects of climate change all pose threats to wildlife.
Moina Spooner, Assistant Editor
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/194178
2022-11-08T11:07:22Z
2022-11-08T11:07:22Z
Comment le changement climatique met en danger la survie des chiens sauvages d’Afrique
<figure><img src="https://images.theconversation.com/files/494056/original/file-20221108-24-eho5op.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Des chiens sauvages d'Afrique..Manoj Shah/GettyImages.</span> </figcaption></figure><p>Les animaux sauvages réagissent et s'adaptent au changement climatique de diverses manières. Certaines adaptations sont plus évidentes. Les plantes à fleurs, par exemple, <a href="https://theconversation.com/plants-are-flowering-a-month-earlier-heres-what-it-could-mean-for-pollinating-insects-176324#:%7E:text=That's%20according%20to%20scientists%20at,days%20earlier%20in%20the%20year.">fleurissent plus</a> tôt chaque année dans certaines parties de l'hémisphère nord, car le changement climatique fait apparaître le printemps de plus en plus tôt dans le calendrier.</p>
<p>D'autres adaptations sont plus discrètes, comme nous l'avons découvert dans le cas du chien sauvage africain, ou “lycaon”.</p>
<p>Le lycaon est un grand carnivore menacé d'extinction dont la population mondiale compte <a href="https://www.iucnredlist.org/species/12436/166502262#assessment-information">moins de 700 meutes</a> (moins de 7 000 individus) réparties sur le continent africain en sous-populations isolées. Ils élèvent généralement leurs petits pendant les mois les plus frais de l'année. Cependant, notre <a href="https://www.pnas.org/doi/full/10.1073/pnas.2121667119">nouvelle étude</a> montre qu'ils s'adaptent au réchauffement des températures en donnant naissance plus tard chaque année, car ils suivent la diminution de la période fraîche.</p>
<p>En suivant le sort de 60 meutes de lycaons dans le delta de l'Okavango au Botswana - la plus grande sous-population restante de l'espèce - nous avons appris que la date moyenne de mise bas est désormais plus de trois semaines plus tard qu'il y a trente ans. Ce décalage correspond presque parfaitement à une augmentation de la température quotidienne moyenne de 1,6 °C au cours de la même période. </p>
<p>À première vue, notre conclusion selon laquelle les lycaons suivent le rythme du réchauffement suggère qu'il n'y a pas lieu de s'alarmer. Les chiots nés pendant <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2656.12719">les mois les plus frais</a> ont plus de chances de survivre. Ne s'agit-il donc pas d'une stratégie efficace pour faire face à un climat changeant ? Malheureusement non.</p>
<p>La période la plus fraîche de l'année étant également de plus en plus courte, l'effet net du suivi de ces changements de température est que les lycaons élèvent désormais par inadvertance leurs petits dans des températures plus chaudes.</p>
<p>C'est un problème car <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2656.12719">nous avons déjà montré</a> que des températures plus élevées après la naissance affectent le taux de survie des petits au Kenya, et notre <a href="https://www.pnas.org/doi/full/10.1073/pnas.2121667119">nouvelle étude</a> montre la même chose au Botswana.</p>
<p>Pendant les trois mois de l'année, lorsque les petits vulnérables restent dans la sécurité de la tanière, la meute doit <a href="https://link.springer.com/article/10.1007/s00265-021-03047-8">parcourir</a> de <a href="https://academic.oup.com/jmammal/article/96/6/1214/1170623?login=false">longues distances</a> entre ses terrains de chasse et la tanière. Il est possible que les coûts de déplacements liés à ces <a href="https://link.springer.com/article/10.1007/BF00296390">livraisons quotidiennes</a> de viande expliquent pourquoi moins de petits ont tendance à survivre aux périodes les plus chaudes de l'année. Il est également possible que les températures plus chaudes affectent le succès de la chasse des chiens. Enfin, les températures élevées sont également liées à une baisse du taux de <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.7601">survie des adultes</a>. Cela peut être dû à des facteurs tels que le coût énergétique de la chasse à des températures élevées. </p>
<p>L'augmentation de la mortalité est une grande menace pour une espèce comme le lycaon, dont la survie dépend de son nombre. En effet, la taille de la meute est inextricablement liée à <a href="https://onlinelibrary.wiley.com/doi/10.1002/ece3.7601">leur survie et à leur succès</a>. Moins de petits survivants signifie moins de futurs auxiliaires pour trouver de la nourriture, ce qui entraîne une diminution du nombre de petits l'année suivante, qui à son tour entraîne une diminution du nombre d'auxiliaires - voilà la situation.</p>
<h2>Aller de l'avant n'est pas une option</h2>
<p>Malheureusement, il n'est pas possible de se déplacer vers des environnements plus adaptés. Les lycaons ont la réputation d'avoir un <a href="https://academic.oup.com/jmammal/article/96/6/1214/1170623?login=false">vaste territoire</a>, les meutes individuelles occupant des domaines vitaux de plusieurs centaines à plus de mille kilomètres carrés. Confinés à seulement <a href="https://www.iucnredlist.org/species/12436/166502262#assessment-information">7 % de leur aire de répartition historique</a>, ils n'ont pas beaucoup de place, et les populations sont naturellement réticents à partager un espace supplémentaire avec <a href="https://www.cambridge.org/core/journals/oryx/article/humanwildlife-conflict-in-northern-botswana-livestock-predation-by-endangered-african-wild-dog-lycaon-pictus-and-other-carnivores/129A71C94A492FE5A6B4EE77100F08F9">des prédateurs</a> qui menacent leur bétail.</p>
<p>En effet, les populations se vengent des pertes de bétail en empoisonnant et en abattant les lycaons, et <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0030099">l'exposition aux maladies</a> des chiens domestiques contribue à leur <a href="https://www.cambridge.org/core/journals/oryx/article/rates-and-causes-of-mortality-in-endangered-african-wild-dogs-lycaon-pictus-lessons-for-management-and-monitoring/E7C8F3C6F42C81A8EAD121477237A56A">déclin</a>.</p>
<h2>Pourquoi cela est-il important ?</h2>
<p>Les lycaons sont pris dans une sorte de piège. Ils s'adaptent à la hausse des températures en utilisant un indice qui, grâce au changement climatique, ne permet plus de prévoir avec précision les meilleures conditions de reproduction.</p>
<p>S'il n'est certainement pas la seule espèce à présenter un changement de comportement lié au climat, le lycaon est, à notre connaissance, le seul grand mammifère carnivore pour lequel un tel changement a été documenté. Le suivi des populations de grands carnivores sur plusieurs décennies étant difficile et coûteux, de telles données à long terme n'existent pas ou n'ont pas été évaluées pour la plupart des grands carnivores.</p>
<p>Cependant, chaque fois que nous recherchons un impact de la température sur les lycaons, nous découvrons quelque chose de nouveau et d'inattendu. Les effets du climat sur le comportement, les populations et le cycle de vie des grands carnivores pourraient bien être plus répandus qu'on ne le pensait. Comme les grands carnivores jouent un rôle important dans le façonnement des écosystèmes, ces impacts ont des implications beaucoup plus larges.</p>
<p>Compte tenu des <a href="https://www.ipcc.ch/report/ar6/wg1/">prévisions d'augmentation </a>continue des températures dans l'ensemble de leur aire de répartition, les effets du changement climatique sur cette espèce déjà menacée - et d'autres comme elle - sont très préoccupants.</p><img src="https://counter.theconversation.com/content/194178/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Neil R. Jordan travaille a la fois au Centre for Ecosystem Science de l'UNSW Sydney et à la Taronga Conservation Society Australia. Il est financé par le National Parks and Wildlife Service NSW, le MidCoast Council, la Hermon Slade Foundation, la Taronga Conservation Society Australia, l'Australian Academy of Science, la Royal Zoological Society of NSW, le WWF-Australie et la Morris Animal Foundation.
</span></em></p><p class="fine-print"><em><span>Briana Abrahms est financée par la Fondation Alfred P. Sloan, The Nature Conservancy et le Royalty Research Fund de Washington University.
</span></em></p><p class="fine-print"><em><span>Daniella Rabaiotti reçoit des fonds du National Environment Research Council du Royaume-Uni et de la British Ecological Society.
</span></em></p><p class="fine-print"><em><span>Kasim Rafiq reçoit des fonds de Washington University.</span></em></p><p class="fine-print"><em><span>Rosie Woodroffe est financée par le Natural Environment Research Council, le Research England, la Morris Animal Foundation et le programme Save Our Species de l'UICN.</span></em></p>
Les chiens sauvages d'Afrique s'adaptent à la hausse des températures en utilisant un indice qui ne permet plus de prévoir avec précision les meilleures conditions de reproduction.
Neil R Jordan, Senior lecturer, UNSW Sydney
Briana Abrahms, Assistant Professor of Biology, University of Washington
Daniella Rabaiotti, Postdoctoral Researcher, Zoological Society of London
Kasim Rafiq, Postdoctoral Researcher in Wildlife Ecology and Conservation, University of Washington
Rosie Woodroffe, Professor, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/189337
2022-11-07T07:26:36Z
2022-11-07T07:26:36Z
Climate change is causing endangered African wild dogs to give birth later – threatening the survival of the pack
<figure><img src="https://images.theconversation.com/files/481898/original/file-20220830-35846-zp39if.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">African wild dog with pups.</span> <span class="attribution"><span class="source">Manoj Shah/GettyImages</span></span></figcaption></figure><p>Wildlife are responding and adapting to climate change in various ways. Some adaptations are more obvious. Flowering plants, for example, are <a href="https://theconversation.com/plants-are-flowering-a-month-earlier-heres-what-it-could-mean-for-pollinating-insects-176324#:%7E:text=That's%20according%20to%20scientists%20at,days%20earlier%20in%20the%20year.">blooming sooner</a> each year in parts of the northern hemisphere as climate change draws the onset of spring progressively earlier in the calendar. </p>
<p>Other adaptations are more covert, as we’ve discovered in the case of the African wild dog. </p>
<p>The African wild dog is an endangered large carnivore with a global population of <a href="https://www.iucnredlist.org/species/12436/166502262#assessment-information">fewer than 700 packs</a> (fewer than 7000 individuals) dotted across the African continent in isolated subpopulations. They typically raise their pups in the cooler months each year. However, our <a href="https://doi.org/10.1073/pnas.2121667119">new study</a> shows that they are adapting to warming temperatures by giving birth later each year as they track a shrinking cool period. </p>
<p>By following the fates of 60 packs of African wild dogs in Botswana’s Okavango delta – the largest remaining subpopulation of the species – we learned that the average birthing date now occurs more than three weeks later than it did three decades ago. This shift almost perfectly tracked an average daily temperature increase of 1.6°C over that same period. </p>
<p>On the face of it, our finding that wild dogs are keeping pace with the rate of warming suggests there is no cause for alarm. Pups born in cooler months <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2656.12719">are more likely to survive</a>, so isn’t this just an effective strategy to cope with a changing climate? Unfortunately not. </p>
<p>As the cooler period of the year is also getting shorter, the net effect of tracking these temperature shifts is that wild dogs are now inadvertently rearing their pups in warmer temperatures. </p>
<p>This is a problem because we’ve also <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2656.12719">shown previously</a> that higher temperatures following birth affect pup survival rates in Kenya, and our <a href="https://doi.org/10.1073/pnas.2121667119">new study</a> shows the same in Botswana. </p>
<p>For the three months of the year, when vulnerable pups remain in the safety of the den, the pack has to <a href="https://link.springer.com/article/10.1007/s00265-021-03047-8">commute</a> <a href="https://doi.org/10.1093/jmammal/gyv130">vast distances</a> between their hunting grounds and the den. It’s possible that the travel costs of these daily <a href="https://link.springer.com/article/10.1007/BF00296390">meat deliveries</a> explain why fewer pups tend to survive at hotter times of the year. It’s also possible that hotter temperatures affect the dogs’ hunting success. And higher temperatures are also related to lower <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.7601">adult survival</a>. This may be because of factors including the energetic costs of hunting at high temperatures.</p>
<p>Increasing mortality is a big threat for a species like African wild dogs, whose survival relies on its numbers. Indeed pack size is inextricably tied to their <a href="https://doi.org/10.1002/ece3.7601">survival and success</a>. Fewer pups surviving means fewer future helpers to find food, which results in fewer pups the next year, which in turn results in even fewer helpers – you get the picture.</p>
<h2>Moving on is not an option</h2>
<p>Unfortunately moving to more suitable environments isn’t an option. African wild dogs are notoriously wide ranging, with single packs occupying <a href="https://academic.oup.com/jmammal/article/96/6/1214/1170623">home ranges</a> of several hundred to over a thousand square kilometres. Confined to just <a href="https://www.iucnredlist.org/species/12436/166502262#assessment-information">7% of their historic range</a>, there is not a lot of room, and people are understandably reluctant to share further space with <a href="https://www.cambridge.org/core/journals/oryx/article/humanwildlife-conflict-in-northern-botswana-livestock-predation-by-endangered-african-wild-dog-lycaon-pictus-and-other-carnivores/129A71C94A492FE5A6B4EE77100F08F9">predators that threaten their livestock</a>. </p>
<p>Indeed people retaliate for stock losses by poisoning and shooting wild dogs, and <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0030099">exposure to disease from domestic dogs</a> contributes further to their <a href="https://www.cambridge.org/core/journals/oryx/article/rates-and-causes-of-mortality-in-endangered-african-wild-dogs-lycaon-pictus-lessons-for-management-and-monitoring/E7C8F3C6F42C81A8EAD121477237A56A">decline</a>.</p>
<h2>Why this matters</h2>
<p>African wild dogs are stuck in a kind of trap. They are adapting to rising temperatures using a cue that, thanks to climate change, no longer accurately predicts the best conditions for reproduction. </p>
<p>While certainly not the only species to exhibit a climate-driven shift in behaviour, African wild dogs are – to the best of our knowledge – the only large mammalian carnivore where a shift has been documented. </p>
<p>Because monitoring large carnivore populations over several decades is challenging and expensive, such long-term data either don’t exist or have not been assessed for most large carnivores. </p>
<p>Every time we look for an impact of temperature on African wild dogs, however, we uncover something new and unexpected. Climate-driven impacts on large carnivore behaviour, populations and life histories may well be more widespread than previously thought. Because large carnivores play an important role in shaping ecosystems, such impacts have much broader implications.</p>
<p>With <a href="https://www.ipcc.ch/report/ar6/wg1/">continued temperature rises projected across their range</a>, the effects of climate change on this already endangered species – and others like it – are of great concern.</p><img src="https://counter.theconversation.com/content/189337/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Neil R Jordan has a conjoint position between in the Centre for Ecosystem Science at UNSW Sydney and Taronga Conservation Society Australia. He receives funding from National Parks and Wildlife Service NSW, MidCoast Council, the Hermon Slade Foundation, Taronga Conservation Society Australia, Australian Academy of Science, Royal Zoological Society of NSW, WWF-Australia, and the Morris Animal Foundation. </span></em></p><p class="fine-print"><em><span>Briana Abrahms receives funding from the Alfred P. Sloan Foundation, The Nature Conservancy, and the University of Washington Royalty Research Fund. </span></em></p><p class="fine-print"><em><span>Daniella Rabaiotti receives funding from the UK National Environment Research Council and the British Ecological Society.</span></em></p><p class="fine-print"><em><span>Kasim Rafiq receives funding from the University of Washington.</span></em></p><p class="fine-print"><em><span>Rosie Woodroffe receives funding from the Natural Environment Research Council, Research England, Morris Animal Foundation, and the IUCN Save Our Species Programme</span></em></p><p class="fine-print"><em><span>John Weldon McNutt receives funding from the UN FAO, Wild Entrust International, St Louis Zoo WildCare Institute, Cincinnati Zoo, Tusk Trust, and numerous private donors.</span></em></p>
African wild dogs are adapting to rising temperatures using a cue that no longer accurately predicts the best conditions for reproduction.
Neil R Jordan, Senior lecturer, UNSW Sydney
Briana Abrahms, Assistant Professor of Biology, University of Washington
Daniella Rabaiotti, Postdoctoral Researcher, Zoological Society of London
Kasim Rafiq, Postdoctoral Researcher in Wildlife Ecology and Conservation, University of Washington
Rosie Woodroffe, Professor, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/183844
2022-07-21T14:04:13Z
2022-07-21T14:04:13Z
Saving East Africa’s wildlife from recurring drought
<figure><img src="https://images.theconversation.com/files/467438/original/file-20220607-14-lkfhsh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A giraffe lies dead in the road near Matanaha village on December 9, 2021 in Wajir County, Kenya. </span> <span class="attribution"><span class="source">Ed Ram/Getty Images</span></span></figcaption></figure><p>Over the past <a href="https://www.sciencedirect.com/science/article/abs/pii/S0012825218303519">two decades</a>, the Horn of Africa – specifically Ethiopia, Somalia and Kenya – has experienced more <a href="https://www.sciencedirect.com/science/article/abs/pii/S004896971935291X">intense</a> and <a href="https://www.sciencedirect.com/science/article/abs/pii/S0012825218303519">frequent</a> droughts. </p>
<p>The affected areas in the three countries include vast rangelands, home to millions of people, livestock and wildlife. These areas are classified as <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/arid-land">arid and semi-arid lands</a>. </p>
<p>These drylands also constitute a <a href="https://www.cepf.net/our-work/biodiversity-hotspots/horn-africa/species">biodiversity hotspot</a>. They harbour endangered species like the hirola antelope, African wild dog, <a href="https://somaligiraffe.org/">Somali giraffe</a> and Grevy’s zebra. But these species face an uncertain future due to severe and recurring droughts.</p>
<p>I’m a Kenyan <a href="https://scholar.google.com/citations?user=q2pK4O8AAAAJ&hl=en">scientist</a> and <a href="https://www.hirolaconservation.org/founder-dr-ali/#page-content">conservationist</a>. One of the hats I wear is as the founder and director of Kenya’s <a href="https://www.hirolaconservation.org/">Hirola Conservation Programme</a>. I have over 15 years of experience working with communities and wildlife in remote areas along the volatile Kenya-Somalia border region. I’ve seen at <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2664.12856">first hand</a> the devastating effect that these droughts have on wildlife and the habitat around them. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1527596418717954050"}"></div></p>
<p>For example, from my observations over the past year, I’ve estimated that 30 endangered hirola (about 6% of the global population) have died as a direct consequence of drought. This is based on <a href="https://www.hirolaconservation.org/">our monitoring</a> of the herds. Hirola live in a small area and we are able to monitor nearly every herd across their range.</p>
<p>Similarly, and during the same period, the deaths of more than 200 giraffes (mostly young and female adults) were reported by members of the <a href="http://www.neca.or.ke/">Northeastern Kenya wildlife Conservancies Association</a> and by the <a href="https://somaligiraffe.org/">Somali giraffe project</a>. This data is estimated from community scout monitoring across conservancies.</p>
<p>There have also been <a href="https://www.bbc.co.uk/news/live/world-africa-61170219?ns_mchannel=social&ns_source=twitter&ns_campaign=bbc_live&ns_linkname=628679984259031cb5a24803%26Drought%20killed%2070%20Kenyan%20elephants%20in%20one%20year%262022-05-19T17%3A29%3A55%2B00%3A00&ns_fee=0&pinned_post_locator=urn:asset:e40df882-fe6d-45c0-a2b4-5782f94cf02d&pinned_post_asset_id=628679984259031cb5a24803&pinned_post_type=share">recent reports</a> that about 70 elephants have died over the past year due to drought in the Tsavo area.</p>
<p>The good news is that there are steps that can be taken towards conserving wildlife, which I’ll unpack later.</p>
<h2>Impacts of drought</h2>
<p>Rangelands are already dry areas. Drought <a href="https://www.sciencedirect.com/science/article/pii/S1877343520300804">adds to</a> the pressure on resources like water and pasture. This makes livestock and wildlife <a href="https://link.springer.com/article/10.1007/s10661-021-09222-8">more susceptible</a> to malnutrition, disease, mass mortalities and competition with each other over resources. </p>
<p><a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2664.12856">In a study</a> in eastern Kenya, I found that between 1970 and 2009, increased drought caused a decline in the area of land covered by grass. Hirola depend entirely on grasses. As a consequence there was a 98% decline in hirola. Elephant populations were similarly affected and there was also a 74% decline in cattle.</p>
<p>Drought also means pastoralists will look for grazing and water closer to, or in, wildlife areas. Livestock diseases <a href="https://www.shh.mpg.de/310600/Janzen-Wildebeest-Mobility">could potentially</a> spill over into wildlife populations and cause mass mortalities. </p>
<p>This has happened before. For instance, an <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2664.12856">outbreak</a> of rinderpest (morbillivirus) among cattle in the mid-1980s killed many hirola. And, in 1991, rinderpest struck in the Mara region and <a href="https://www.researchgate.net/profile/Thomas-Butynski/publication/287391841_Independent_Evaluation_of_Hirola_Antelope_Beatragus_hunteri_Conservation_Status_and_Conservation_Action_in_Kenya/links/56763fe508ae125516e731ae/Independent-Evaluation-of-Hirola-Antelope-Beatragus-hunteri-Conservation-Status-and-Conservation-Action-in-Kenya.pdf?origin=publication_detail">wiped out</a> 95% of the buffalo and wildebeest population.</p>
<p>In fact, since 2021’s prolonged drought there has already <a href="https://www.ndma.go.ke/index.php/resource-center/send/5-garissa/6175-garissa-august-2021">been an increase</a> in the number of bovine trypanosomiasis (“sleeping sickness”) cases reported in parts of southern Garissa in Kenya. This is a worry because at least 24 hirola antelopes <a href="https://www.researchgate.net/publication/287391841_Independent_Evaluation_of_Hirola_Antelope_Beatragus_hunteri_Conservation_Status_and_Conservation_Action_in_Kenya">died from</a> cattle diseases in 1998. </p>
<p>Drought favours the <a href="https://www.ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_CrossChapterPaper1.pdf">encroachment</a> of invasive woody plants. This <a href="https://www.researchgate.net/publication/228571211_The_Impact_of_Rangeland_Condition_and_Trend_to_the_Grazing_Resources_of_a_Semi-arid_Environment_in_Kenya">reduces</a> the habitats of wildlife species and increases the risk of local extinction. </p>
<p>The <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2664.12856">hirola</a> and the endangered <a href="https://www.tandfonline.com/doi/full/10.1080/20964129.2018.1530054">Ethiopian wolf</a> are some of the species whose ranges have been reduced by <a href="https://link.springer.com/article/10.1007/s00703-016-0462-0">warming trends</a> and the <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2664.12856">spread</a> of woody plants. </p>
<h2>Recurring droughts</h2>
<p>The wildlife in these regions live alongside people who are struggling to survive and keep their livestock alive. Poaching has <a href="https://ke.opera.news/ke/en/environment/3507b27ea1e91a6621439c570296cd7a">increased</a> in the conservation areas where we work. </p>
<p>Drought conditions have therefore become a <a href="https://www.sciencedirect.com/science/article/abs/pii/S0012825218303519">major threat</a> to all wildlife species. </p>
<p>Their increased frequency means there’s <a href="https://reliefweb.int/report/ethiopia/horn-africa-drought-humanitarian-key-messages-23-march-2022">little or no time</a> to recover before the next drought occurs. </p>
<p>This is what we’re experiencing now. A prolonged drought was declared a <a href="https://www.standardmedia.co.ke/national/article/2001422964/president-uhuru-declares-drought-a-national-disaster">national disaster</a> in Kenya in September 2021. A little rainfall in December gave only temporary reprieve. New forage lasted about a month. Partially recharged water sources quickly deteriorated during the hot month of January. Crops did not germinate and wilted without moisture. It is estimated that farmers produced only about <a href="https://journals.ametsoc.org/view/journals/bams/100/6/bams-d-17-0233.1.xml">30%</a> of the norm. </p>
<p>People and animals migrated into core wildlife areas which have more undisturbed vegetation compared to open communual areas. On 23 March 2022, the Kenyan government <a href="https://www.kenyans.co.ke/news/74201-uhuru-declares-curfew-these-areas">imposed</a> a dusk to dawn curfew in some parts of the region because of increasing resource-based conflicts. </p>
<h2>No capacity to deal with changes</h2>
<p>The countries in the Horn of Africa are <a href="https://www.mdpi.com/1660-4601/17/16/5917/htm">highly vulnerable</a> to prolonged droughts, erratic rains and increased temperatures, but they don’t really have the capacity to cope with these climatic changes. The governments rely on <a href="https://catalogue.unccd.int/725_White_paper_second_draft_Namibia_Drought_2016.pdf">crisis management</a> and the responses tend to be humanitarian, forgetting wildlife.</p>
<p>As I mentioned before, I established and work with the <a href="https://www.hirolaconservation.org/">Hirola Conservation Programme</a>. The hirola antelope – classified as critically endangered by the <a href="https://www.iucn.org/">International Union for Conservation of Nature</a> – is among the 10 species most at risk of imminent extinction. The population has fallen by 95% in the last four decades. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/475510/original/file-20220721-9523-hb1h2a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/475510/original/file-20220721-9523-hb1h2a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/475510/original/file-20220721-9523-hb1h2a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/475510/original/file-20220721-9523-hb1h2a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/475510/original/file-20220721-9523-hb1h2a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/475510/original/file-20220721-9523-hb1h2a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/475510/original/file-20220721-9523-hb1h2a.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">Hirola antelope.</span>
<span class="attribution"><span class="source">OliverZeid/Shutterstock</span></span>
</figcaption>
</figure>
<p>The programme includes both long-term climate-change resilience measures and <a href="https://www.youtube.com/watch?v=2awvGJut8Mc">short-term emergency initiatives</a> to ensure wildlife, local communities and their livestock survive during drought periods.</p>
<p>We offer some experiences for policymakers to draw on.</p>
<h2>Solid solutions</h2>
<p>Well-managed protected areas are the key in biodiversity conservation. Because wildlife species <a href="https://onlinelibrary.wiley.com/doi/epdf/10.1111/ecog.00967">shift</a> their geographic ranges in response to climate change, it makes sense to create <a href="https://academic.oup.com/biolinnean/article/115/3/718/2440232?login=true">a network</a> of protected areas within a region to <a href="https://esajournals.onlinelibrary.wiley.com/doi/10.1890/1540-9295%282007%295%5B131%3APANIAC%5D2.0.CO%3B2">accommodate movement</a>. This can also be good for tourism, local employment and incomes.</p>
<p>In line with this, we have a <a href="https://www.ser.org/news/553105/www.hirolaconservation.org">10-year rangelands project</a> which aims to restore 10,000 acres of grasslands in the Horn of Africa. It creates corridors to connect wildlife habitats.</p>
<p>We have also established two protected areas within the hirola’s native range. Here, elephants are making a comeback and we’ve had increased sightings of African wild dogs, Somali giraffes, lions and Grevy’s zebra.</p>
<p>The national and county governments could build on these efforts. </p>
<p>Our emergency initiatives to cushion wildlife and communities against drought include:</p>
<ul>
<li><p>trucking in water and fuel to communities</p></li>
<li><p>supplying food to wildlife and supplements to livestock</p></li>
<li><p>conduct regular patrols to identify and rescue vulnerable animals </p></li>
<li><p>opening wildlife water access corridors by thinning invasive thickets and mapping all natural water access points for long-term protection </p></li>
<li><p>vaccinating livestock and treating wildlife to reduce the chances of disease spillover and improve animal health.</p></li>
</ul>
<p>In addition to expanding on these measures, policymakers must invest in water resource management and <a href="https://www.sciencedirect.com/science/article/abs/pii/S0048969717337324?via%3Dihub">maintain</a> infrastructure. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/groundwater-can-prevent-drought-emergencies-in-the-horn-of-africa-heres-how-124837">Groundwater can prevent drought emergencies in the Horn of Africa. Here's how</a>
</strong>
</em>
</p>
<hr>
<p>As droughts become more frequent, much can be done to reduce their impact. It requires a multi-agency approach which brings communities, government and conservationists together.</p><img src="https://counter.theconversation.com/content/183844/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Abdullahi Ali is affiliated with the Society for Conservation Biology, Kenya Chapter as the President </span></em></p>
Many wildlife species face an uncertain future due to recurring, severe drought.
Abdullahi Ali, Fellow, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/181665
2022-04-27T16:24:25Z
2022-04-27T16:24:25Z
Tigray in Ethiopia was an environmental success story – but the war is undoing decades of regreening
<p>An <a href="https://www.bbc.com/news/world-africa-54964378">ongoing war</a> between the Ethiopian government and its allies against Tigray, one of its northern states, has led to one of the world’s biggest <a href="https://www.theguardian.com/global-development/2022/jan/14/ethiopia-tigray-on-brink-of-humanitarian-disaster-un-says">humanitarian crises</a>. </p>
<p>We have used satellite data to track how the conflict and resulting energy crisis has also broken the relationship between humans and nature. People have been forced to use firewood, causing a loss of vegetation in a region on the forefront of environmental rehabilitation. That’s the key finding of our new report published by the <a href="https://ceobs.org/the-war-in-tigray-is-undermining-its-environmental-recovery/">Conflict and Environment Observatory</a>.</p>
<p>Tigray is semi-arid, and people there, like most of Ethiopia’s population, <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0186406">depend</a> on subsistence agriculture fed by rainfall for a large part of their diet. When cropping is disrupted by insufficient rainfall or other causes, alternative sources of income or food are also often insufficient, contributing to catastrophic famines, such as in the 1980s.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/460035/original/file-20220427-1097-bhzjej.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map of Ethiopia" src="https://images.theconversation.com/files/460035/original/file-20220427-1097-bhzjej.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/460035/original/file-20220427-1097-bhzjej.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=536&fit=crop&dpr=1 600w, https://images.theconversation.com/files/460035/original/file-20220427-1097-bhzjej.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=536&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/460035/original/file-20220427-1097-bhzjej.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=536&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/460035/original/file-20220427-1097-bhzjej.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=673&fit=crop&dpr=1 754w, https://images.theconversation.com/files/460035/original/file-20220427-1097-bhzjej.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=673&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/460035/original/file-20220427-1097-bhzjej.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=673&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Tigray (in red) is Ethiopia’s northernmost regional state and borders Sudan and Eritrea.</span>
<span class="attribution"><span class="source">Google Maps</span></span>
</figcaption>
</figure>
<p>Conventional agricultural development policies – such as farmers’ access to fertilisers, loans or markets – have only had <a href="https://webapps.itc.utwente.nl/librarywww/papers_2010/scie/vanderveen_eff.pdf">modest</a> <a href="https://www.ecologyandsociety.org/vol16/iss1/art18/">effects</a> on productivity. In the 1990s, the Tigray government instead <a href="https://www.ecologyandsociety.org/vol16/iss1/art18/">adopted</a> a conservation-based policy to address persistent food insecurity and low agricultural productivity.</p>
<p>The new strategy focused on making the land better at <a href="https://www.researchgate.net/profile/Jan-Nyssen/publication/228868174_Soil_and_water_conservation_through_forest_restoration_in_exclosures_of_the_Tigray_highlands/links/5602423408aeb30ba7355c16/Soil-and-water-conservation-through-forest-restoration-in-exclosures-of-the-Tigray-highlands.pdf">retaining water and soil</a>, two key ingredients of agricultural production. This meant building stone and soil berms (raised barriers) that slowed down overland water flows, reducing erosion rates. </p>
<p>It also meant creating ponds in which runoff water could be stored. And it involved banning livestock grazing and wood cutting in patches of degraded land so it could regenerate. These “exclosures” act like sponges, allowing rainwater to infiltrate the soil rather than running off.</p>
<p>Over three decades, this approach <a href="https://www.sciencedirect.com/science/article/abs/pii/S014019631730232X">transformed</a> the Tigrayan landscape, leading to widespread recovery of trees and shrubs, reduced erosion and rising groundwater tables. This allowed the expansion of irrigated agriculture and, most importantly, agricultural yields indeed <a href="https://www.sciencedirect.com/science/article/abs/pii/S014019631730232X">increased</a>.</p>
<p>Terraces, which slow down the flow of water and trap soil, are visible on these mountain slopes. Over the past few decades, people across Tigray have worked – sometimes in exchange for food or money, but often unpaid – to create such soil and water conservation structures, transforming the landscape and making it more productive.</p>
<h2>Why war is bad news for trees</h2>
<p>However, this success has now come under threat from the war which began in November 2020. Since then, the region has been under a <a href="https://www.bbc.co.uk/news/world-africa-58921744">blockade</a>, leading to a collapse in food and fuel supplies. Electricity has been disrupted and unreliable, and banking and telecommunication services have been suspended. </p>
<p>This has created a huge humanitarian crisis: 1.8 million people have been <a href="https://reports.unocha.org/en/country/ethiopia/card/VpEQOi2S9a/">displaced</a> far away from their homes, and 83% of people in Tigray are estimated to face <a href="https://docs.wfp.org/api/documents/WFP-0000136281/download/?_ga=2.179994148.1299319079.1644948428-577913078.1644948428">acute food shortages</a>.</p>
<p>Cut off from alternative supplies for cooking fuel, people may have to turn to local sources of wood, despite regulations against cutting vegetation in exclosures. Contacts in Tigray shared with us their concerns about the pressures that the energy crisis is putting on trees and shrubs. And vegetation declines were indeed visible in the few open-access, high-resolution satellite images available on Google Earth taken after November 2020. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/460046/original/file-20220427-24-g4bm90.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Satellite image" src="https://images.theconversation.com/files/460046/original/file-20220427-24-g4bm90.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/460046/original/file-20220427-24-g4bm90.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=327&fit=crop&dpr=1 600w, https://images.theconversation.com/files/460046/original/file-20220427-24-g4bm90.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=327&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/460046/original/file-20220427-24-g4bm90.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=327&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/460046/original/file-20220427-24-g4bm90.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=411&fit=crop&dpr=1 754w, https://images.theconversation.com/files/460046/original/file-20220427-24-g4bm90.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=411&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/460046/original/file-20220427-24-g4bm90.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=411&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An area of restored vegetation in Tigray at the start of the war…</span>
<span class="attribution"><span class="source">Google Earth / Maxar Technologies</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/460048/original/file-20220427-18-d063l7.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Satellite image" src="https://images.theconversation.com/files/460048/original/file-20220427-18-d063l7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/460048/original/file-20220427-18-d063l7.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=327&fit=crop&dpr=1 600w, https://images.theconversation.com/files/460048/original/file-20220427-18-d063l7.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=327&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/460048/original/file-20220427-18-d063l7.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=327&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/460048/original/file-20220427-18-d063l7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=411&fit=crop&dpr=1 754w, https://images.theconversation.com/files/460048/original/file-20220427-18-d063l7.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=411&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/460048/original/file-20220427-18-d063l7.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=411&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">…and the same area a few months later. The vegetation has been turned into charcoal.</span>
<span class="attribution"><span class="source">Google Earth / Maxar Technologies</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>However, it was difficult to gauge the extent of the problem as the region remains <a href="https://www.bbc.co.uk/news/world-africa-60943889">largely inaccessible</a>. We therefore turned to open-access data from the EU’s <a href="https://scihub.copernicus.eu/">Copernicus satellites</a>, which provide regularly updated images of the whole of Tigray.</p>
<p>We looked for areas where woody vegetation had declined since the start of the war, and found certain hotspots with a strong decrease in <a href="https://gisgeography.com/ndvi-normalized-difference-vegetation-index/">NDVI</a>, a commonly used index for greenness of the landscape. Potential alternative drivers of these declines – rainfall, temperatures, fires and locust outbreaks – showed little overlap with these hotspots of woody vegetation decline. </p>
<p>Woody vegetation continued to thrive in other places in Tigray during the same period, but – when compared to pre-conflict years – vegetation recovery was subdued. This led us to conclude that declines were likely being intensified by the conflict.</p>
<p>The history of the Tigrayan landscape shows that losing woody vegetation cover leads to soil erosion and water run-off, decreasing agricultural productivity in a region already suffering from widespread hunger and expecting another drought <a href="https://theconversation.com/scientists-sound-the-alarm-over-drought-in-east-africa-what-must-happen-next-168095">this year</a>. In the long term, pressures from <a href="https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter_12.pdf">climate change</a> – including increasing downpours, which can contribute to erosion, and droughts – are likely to continue. </p>
<p>Woody vegetation, a key soil and water conservation component, is thus being eroded at a time when it is crucial to the long-term wellbeing of people in Tigray. On a more positive note, previous landscape restoration efforts are providing a buffer for the environmental impact of the war, as losses of woody vegetation are likely occurring from a higher baseline than they would have previously.</p>
<p>Yet we still don’t know what impact the war will have on the region’s wildlife or water cycles. Neighbouring regions such as Amhara and Afar, into which the conflict has spilled since July 2021, could also be affected. </p>
<p>It is important that the environmental impacts of the war are fully assessed on the ground to inform recovery strategies. Only if the environment thrives can the long-term wellbeing of people in conflict-affected areas be assured.</p><img src="https://counter.theconversation.com/content/181665/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Henrike Schulte to Bühne is affiliated with the Institute of Zoology (Zoological Society of London). </span></em></p><p class="fine-print"><em><span>Doug Weir is the Research and Policy Director of the Conflict and Environment Observatory, a charity that has received funding from the Norwegian Ministry of Foreign Affairs.</span></em></p><p class="fine-print"><em><span>Jan Nyssen receives funding from the Belgian Government, through VLIR University Development Cooperation and through FWO Fund for Scientific Research. Ghent University also provides funding through its Special Research Fund.</span></em></p><p class="fine-print"><em><span>Teklehaymanot G. Weldemichel is affiliated with the Norwegian University of Science and Technology. </span></em></p>
We used satellite imagery to track the decline of vegetation since the civil war began.
Henrike Schulte to Bühne, Honorary Research Associate, Zoological Society of London
Doug Weir, Research and Policy Director at the Conflict and Environment Observatory, and Visiting Research Fellow, Dept of Geography, King's College London
Jan Nyssen, Professor of Geography, Ghent University
Teklehaymanot G. Weldemichel, Postdoctoral fellow, Norwegian University of Science and Technology
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/122666
2019-08-30T13:37:03Z
2019-08-30T13:37:03Z
Spiders are threatened by climate change – and even the biggest arachnophobes should be worried
<figure><img src="https://images.theconversation.com/files/290137/original/file-20190829-106494-4osj3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">As the world warms, male ladybird spiders are hatching too early in the year to meet a mate.</span> <span class="attribution"><span class="source">MF Photo / shutterstock</span></span></figcaption></figure><p>Is climate change making spiders more aggressive? A recent <a href="https://www.nature.com/articles/s41559-019-0951-x">scientific study</a> suggests so, as the researchers link aggressiveness to tropical cyclones, events that are expected to become more frequent and powerful with climate change. Unsurprisingly, the findings got considerable media coverage. After all, it matches justified fears of catastrophic climate change impacts, with the unjustified fear many people have of harmless spiders. </p>
<p>However, I have studied these arachnids for more than 15 years and I am not too concerned about tropical cyclones making them more aggressive. It is worth worrying about spiders themselves though. </p>
<p>People who dislike spiders will of course be alarmed by any news of them getting more aggressive or even <a href="https://www.pnas.org/content/115/32/E7541">bigger due to climate change</a>. But beyond the headlines, it is important to note that they might be <a href="https://theconversation.com/city-spiders-are-getting-bigger-but-thats-a-good-thing-30605">getting bigger for a number of reasons</a>, and that these are localised studies made on target species. Therefore warming temperatures are unlikely to impact the recorded <a href="https://wsc.nmbe.ch/">48,359 species</a> globally in the same way.</p>
<p>In any case, <a href="https://core.ac.uk/download/pdf/82833978.pdf">a study found</a>that people who fear spiders are more likely to view them as larger than people who do not. And as I write this article at the end of summer in the Northern Hemisphere, one of the biggest common spiders in Europe (the garden-orb-weaver, or <a href="http://srs.britishspiders.org.uk/portal.php/p/Summary/s/Araneus+diadematus"><em>Araneus diadematus</em>)</a>) is now reaching maturity, so you might just come across “large” spiders in the middle of their webs more often at this time of year.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/290141/original/file-20190829-106475-6jeo3b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/290141/original/file-20190829-106475-6jeo3b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/290141/original/file-20190829-106475-6jeo3b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/290141/original/file-20190829-106475-6jeo3b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/290141/original/file-20190829-106475-6jeo3b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/290141/original/file-20190829-106475-6jeo3b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/290141/original/file-20190829-106475-6jeo3b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/290141/original/file-20190829-106475-6jeo3b.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">Orb spiders: big in late summer.</span>
<span class="attribution"><span class="source">Sergey / shutterstock</span></span>
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</figure>
<p>As for aggression, the study that reportedly shows an increase with climate change only actually looked at the impact of tropical cyclones on a single species: the <a href="https://bugguide.net/node/view/50215">group-living spider</a> (<em>Anelosimus studiosus</em>). Also known as the communal spider, these are often found alone or in groups of up to a few hundred individuals, and each individual is born with <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1461-0248.2012.01825.x">either an “aggressive” or “docile” behavioural type</a> (the new study showed that after cyclones the ratio between the two would consistently change towards more aggressive colonies). </p>
<p>Communal behaviour is fairly rare in spiders, which is why this species is so interesting to study. But it is also what makes it less representative of other spiders behaviour, and not the best model to understand climate change impact on spiders globally.</p>
<p>But what if you’re still worried about that one harmless species, smaller than a centimetre, potentially becoming more aggressive? In that case, it might be useful to note that aggressiveness in this context was measured as speed and number of spiders that respond to prey (who wouldn’t run to food if they were really hungry), prey-sharing efficiency and reduce wastage (aka, want not waste not), tendency to cannibalise males and eggs (desperate times call for desperate measures) and less susceptibility to infiltration by foreign spiders (aka, when the going gets tough, the tough don’t like sharing). Therefore, if you are not an insect, there is no cause for alarm – their “aggression” is not aimed at humans.</p>
<h2>Don’t be afraid of spiders – be afraid for spiders</h2>
<p>But, although there is no reason to be concerned about their size or aggressiveness, you should be worried about spider survival under climate change. To take one example, just last year I was researching the beautiful ladybird spider in the western Asian highlands (I’m keeping the location secret as these animals are sought after by the illegal pet trade). Where I observed the males maturing much earlier in the year than they would normally do, thanks to an unusual hot period in winter. </p>
<p>For them, this was a disaster. These male ladybird spiders usually leave their nests in spring to find suitable females, but this time they would emerge into the wider world only to find no females yet available to mate, as females appear to depend on food intake to reach sexual maturity rather than wait for environmental cues, such as temperature. Like Romeo, these males died without their Juliet.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/290307/original/file-20190830-166019-3qp9j1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/290307/original/file-20190830-166019-3qp9j1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/290307/original/file-20190830-166019-3qp9j1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/290307/original/file-20190830-166019-3qp9j1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/290307/original/file-20190830-166019-3qp9j1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/290307/original/file-20190830-166019-3qp9j1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/290307/original/file-20190830-166019-3qp9j1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/290307/original/file-20190830-166019-3qp9j1.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">A jumping spider tucks into a mosquito.</span>
<span class="attribution"><span class="source">vinit thongtue / shutterstock</span></span>
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</figure>
<p>You should care about all this because spiders eat an <a href="https://link.springer.com/article/10.1007%2Fs00114-017-1440-1">astronomical amount of insects</a>, many of which are agricultural pests or the carries of human diseases, their loss will become ours as it <a href="http://www.indefenseofplants.com/blog/2017/5/4/how-spiders-increase-plant-diversity">impacts future ecosystems</a>.</p>
<p>Furthermore, although unappreciated and understudied, spiders have untapped potential to help us develop new medicine or materials with their venom or <a href="https://www.youtube.com/watch?v=EqzWIfbciXU">silk</a>. You should also care because this type of impact might be particularly dire in desert dwelling animals, which <a href="https://www.nhm.ac.uk/discover/news/2019/january/velvet-spider-named-after-lou-reed-found-in-europe-for-the-first.html">already live at the threshold of what they can tolerate</a>, so even small temperature increases and more frequent heat waves, can wipe entire populations and drastically change those ecosystems. Which is more likely to happen in regions where losing key biocontrol agents such as spiders, might put even more pressure on crops and on the human populations <a href="https://gain.nd.edu/our-work/country-index/">disproportionately affected by climate change</a>.</p>
<p>If we continue to disregard the value of these animals, not only will <a href="https://www.bbc.co.uk/news/uk-england-london-45797599">our fear likely cause disruption</a> or <a href="https://www.unilad.co.uk/news/us-news/woman-crashes-car-after-seeing-a-spider-while-driving/?source=facebook">put us in actual danger</a>, but ignoring them now might drive them to disappear forever. </p>
<p>In the famous <a href="https://www.nytimes.com/2000/07/04/science/essay-lost-rivets-and-threads-and-ecosystems-pulled-apart.html">aeroplane analogy</a>, species are compared with losing a couple of bolts that still allow the plane to fly, but as you lose more and more parts, you’re getting dangerously close to crashing. Well, spiders are part of the engine in this analogy. Wouldn’t you be worried if the aeroplane you are flying in, the spaceship we are all in, was losing engine parts in front of your eyes?</p><img src="https://counter.theconversation.com/content/122666/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sergio Henriques receives funding from the Natural Environment Research Council and is a member of the International Union for Conservation of Nature.</span></em></p>
Don’t be afraid of spiders – be afraid for spiders
Sergio Henriques, Chair of the IUCN Spider and Scorpion Specialist Group, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/120660
2019-07-21T20:02:30Z
2019-07-21T20:02:30Z
It’s Sarabi’s pride, Mufasa just lives there: a biologist on The Lion King
<p>Last week saw the release of the rebooted The Lion King, an attempt to capitalise on the billion-dollar success of the 1994 original. With a star-studded cast, the reboot closely follows the plot of the first movie (spoilers to follow, obviously).</p>
<p>Mufasa, king of the lions (and of every other creature in his territory), raises his son Simba to follow in his footsteps. But Mufasa is murdered by his jealous brother Scar, and his young heir is chased into the desert. Years pass, and eventually Simba reclaims his rightful place as the ruler of Pride Rock. </p>
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Read more:
<a href="https://theconversation.com/lions-sometimes-suffer-if-they-attack-a-porcupine-so-why-do-they-do-it-117849">Lions sometimes suffer if they attack a porcupine. So why do they do it?</a>
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<p>The remake is likely to be the box office hit of 2019. But in my job as a big cat biologist, I spend plenty of time with Pride Rock’s real-life counterparts. While Disney was somewhat accurate, the real life dynamics of a lion pride in Uganda or Tanzania’s national parks can be far more Game of Thrones than The Circle of Life. </p>
<h2>Sarabi’s pride: the anchors of lion society</h2>
<p>The key to survival in lion society is strength in numbers, and lionesses are the anchors of lion prides. They form a matrilineal society, and generally stay in the territory of their birth. It is the males that leave. </p>
<p>The Lion King gets the fundamental premise of pride society right: its strength is the <a href="https://science.sciencemag.org/content/293/5530/690">number of lionesses</a> in a pride. </p>
<p>You might assume this would be for successful hunting, but far more fundamentally, it is the key to successfully raising young. Lionesses will often give birth at a similar time (usually a few months apart). This means they can suckle each other’s cubs. </p>
<p>Genetically, this makes sense, as they are related as mothers, sisters, aunts and nieces. If one lioness dies, a relative will raise her offspring. Moreover the strength of numbers means lionesses can defend their cubs from males trying to kill them. </p>
<p>Males (typically not the father) will kill cubs to force their mothers back into heat. Infanticide is one of the the leading causes of death for young lions; about <a href="https://www.nationalgeographic.com/magazine/2013/08/serengeti-lions/">25% of all lion cubs</a> will die in this way. It is perhaps understandable why Disney chose to omit this aspect of lion society from their children’s films. </p>
<h2>Scar and Mufasa would be partners, not enemies</h2>
<p>Where the Lion King takes a turn towards fiction is in the relationship between Scar and Mufasa. In the film they are brothers, and enemies. But in real life they would be partners and rely intimately on each other. </p>
<p>In lion society, young males are evicted from their mothers’ pride once they mature. To survive they <a href="https://www.nature.com/articles/282839a0%E2%80%8B">band together</a>, looking for a new pride they can take up residency in and sire offspring. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/k0hcFLeuUDc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
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<p>The more males in a coalition, the higher the likelihood they will secure tenure in a new female pride. Yes, Mufasa and Scar may have had the odd squabble over mating rights to females in the pride, but they wouldn’t kill each other. </p>
<p>Instead, their fight would be with other males. Arguably the best example of this was seen in the mid-2000s in South Africa’s Sabi-Sands game reserve. A coalition of six adolescent males, <a href="https://africageographic.com/blog/the-legend-of-the-mapogo-lions/">known as the Mapogos</a> (meaning rogues or vigilantes), joined forces to rule an area of 170,000 acres for six years.</p>
<p>They sired a multitude of offspring, but killed at least 40 cubs, females and adult males during their reign, before finally being dispatched by two other lion coalitions (the Majingilanes and the Southern Pride).</p>
<p>Interestingly, in the 1994 original Scar was the bearer of a gorgeous, black mane, far darker than his brother Mufasa’s. Seminal experiments with dummy lions showed lionesses <a href="https://science.sciencemag.org/content/297/5585/1339%E2%80%8B">prefer males with darker manes</a>.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/XkU23m6yX04?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Scar’s dark mane would be irresistible to lionesses. In real life, however, lions generally do not command armies of hyenas.</span></figcaption>
</figure>
<p>Those same dark-maned males feature more testosterone and can heal up quicker after big fights. Rather than the outcast Scar is made out to be, his black mane would be an important indicator of fitness and very sexy to lionesses! </p>
<h2>Run away and (really) never return</h2>
<p>One of the key moments in The Lion King is Simba leaving his mother’s pride, fuelled by guilt over Mufasa’s death. </p>
<p>The act of leaving is dead right, but it would not have been voluntary. Adult lions cannot stand the presence of young and upcoming males in their areas, although they will tolerate young cubs to a degree. When males are between two and a half and about four, they are forcibly evicted by their fathers, uncles and other pride members. </p>
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<p>I recently saw one of my favourite Ugandan lions, a 3 year-old male called Jacob (pictured below), get swatted around by a coalition of three massive mature males. Jacob immediately submitted, laying on his back and cowering. Simba’s journey away from home would not have been a smooth one.</p>
<p>When lions leave their birth pride, they’re setting out on a long, arduous journey (which makes it all the more important to have your brother or cousin with you). </p>
<p>Lions can move hundreds of kilometres in search of a new “home”, a new pride they can challenge the incumbent males for. They can cross electrified fences into new reserves, move across cattle farms and even <a href="https://www.cambridge.org/core/services/aop-cambridge-core/content/view/CDE002EC458890809D81DDE543821D99/S0952836902003126a.pdf/reduced_dispersal_and_opportunistic_territory_acquisition_in_male_lions_panthera_leo.pdf">international borders</a>.</p>
<p>The likelihood of Simba returning to his mother’s pride are next to none, barring some extreme event resulting in the males dying (for example trophy hunters or poachers). Of course, if he did return, it would be to mate with as many lionesses as he could, many of whom – if not all – would be closely related to him. </p>
<p>While I personally revel in the opportunity to study lion society in its totality, even the fights and hardships, I can understand why Disney chose to skim over some of these aspects of lion life in favour of fantasy. </p>
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<p>
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<strong>
Read more:
<a href="https://theconversation.com/dynasties-lions-may-disappear-without-urgent-funding-for-conservation-107116">Dynasties: Lions may disappear without urgent funding for conservation</a>
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<p>Although the story of The Lion King is ultimately positive, African lions are thought to have undergone a <a href="https://theconversation.com/dynasties-lions-may-disappear-without-urgent-funding-for-conservation-107116">50% decline</a> since the original film. The new Lion King gives us all an opportunity to be inspired by this magnificent cat and help its conservation in the wild.</p><img src="https://counter.theconversation.com/content/120660/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Carbone receives government funding through Research England.</span></em></p><p class="fine-print"><em><span>Alexander Richard Braczkowski 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>
Lions don’t generally have armies of hyenas, but not every aspect of The Lion King is inaccurate.
Alexander Richard Braczkowski, PhD Candidate - Wildlife Cameraman, The University of Queensland
Chris Carbone, Senior Research Fellow, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/102595
2018-10-24T21:21:38Z
2018-10-24T21:21:38Z
Comment, au sortir des océans, la vie a fleuri sur la terre
<figure><img src="https://images.theconversation.com/files/242018/original/file-20181024-48697-9v7ozp.png?ixlib=rb-1.1.0&rect=0%2C1%2C1200%2C772&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Un sporange datant de la fin du Silurien. En vert : une tétrade de spores. En bleu: une spore marquée d'un trilète. Les spores ont un diamètre d'environ 30 à 35 µm.</span> <span class="attribution"><a class="source" href="https://fr.wikipedia.org/wiki/Histoire_%C3%A9volutive_des_v%C3%A9g%C3%A9taux#/media/File:Trilete_spores.png">Smith609/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p><em>Nous publions ici un extrait du livre « Évolution », coordonné par Steve Parker, qui paraît ce jour aux Éditions Delachaux & Niestlé.</em></p>
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<p>Quand la vie s’est-elle affranchie des océans pour gagner la terre ? Les fossiles qui pourraient concourir à préciser ce moment sont quasiment inexistants. Ce processus évolutif a requis des millions d’années et la fossilisation reste un événement rare, d’autant plus lorsqu’il s’agit de tissus végétaux fragiles comme dans le cas de cet <a href="https://en.wikipedia.org/wiki/Asteroxylon">Asteroxylon</a>. Au vu des rares vestiges, il est probable que la colonisation des terres émergées par la vie végétale débuta à l’<a href="https://fr.wikipedia.org/wiki/Ordovicien">ordovicien</a>, il y a 485 à 443 millions d’années, mais il est possible que ce processus ait commencé en fait bien antérieurement.</p>
<h2>Un afflux d’oxygène</h2>
<p>Avant que la vie n’ait pris pied sur la terre ferme, l’atmosphère de la planète a dû changer. Elle était initialement pauvre en oxygène puisqu’elle renfermait moins de 1 % de la concentration actuelle. L’oxygène forme de l’ozone dans les hautes couches atmosphériques, un gaz qui – cela importe pour la vie – absorbe les rayons ultraviolets potentiellement dangereux. Sans couche d’ozone, la vie serait exposée sur terre à trop de radiations qui induiraient des ruptures de l’ADN, des mutations génétiques et occasionneraient donc des cancers. Ainsi, ce n’est qu’une fois que la photosynthèse réalisée par des organismes aquatiques eût produit suffisamment d’oxygène pour former la couche d’ozone qu’il devint possible que des espèces fragiles survivent.</p>
<p>Ce processus nécessita des centaines de millions d’années. Les scientifiques s’accordent désormais à penser que les plantes ne furent pas les premiers organismes à coloniser la terre car, en plus de la lumière solaire et du dioxyde de carbone, il leur fallait en effet des nutriments absorbables. L’étude des paléosols (sols fossilisés) suggère que les terres émergées furent investies en premier par des bactéries. Cyanobactéries, algues, champignons et peut-être lichens participèrent ainsi à la formation des premiers sols dans lesquels les plantes puisèrent des nutriments.</p>
<p>Les algues vertes <a href="https://fr.wikipedia.org/wiki/Charophyceae">charophycées</a> sont généralement tenues comme les ancêtres des plantes terrestres : l’étude de leur métabolisme et de leur génome montre qu’elles avaient plus de choses en commun avec les végétaux terrestres archaïques qu’avec les espèces actuelles. Le premier fossile de plante véritable date du <a href="https://fr.wikipedia.org/wiki/Silurien">silurien</a> (443-419 millions d’années). Les couches de cette époque livrent aussi des fossiles de mille-pattes, de chilopodes et d’arachnides se nourrissant de débris végétaux, prouvant qu’il existait donc déjà de vrais écosystèmes terrestres. En colonisant les terres, les plantes gagnèrent une dynamique évolutive qui explique la diversité que nous connaissons aujourd’hui.</p>
<h2>Milieu terreste hostile</h2>
<p>Alors que les océans constituaient un environnement relativement stable, la surface était un milieu hostile dont la conquête relevait du défi pour des cellules avant tout constituées d’eau, et qui s’y exposaient à un risque de déshydratation. Il est probable que l’arrivée des plantes sur la terre ferme coïncida avec une période de changement climatique : la succession de périodes humides et sèches aurait eu raison des formes de vie mal adaptées aux conditions environnementales trop drastiques de la vie sur terre. Le flux et reflux des vagues sur le littoral purent constituer une opportunité facilitant l’accès à ce milieu. Les plantes se protégèrent en développant une cuticule cireuse pour prévenir les pertes hydriques et créèrent des pores (stomates) permettant les échanges gazeux avec l’atmosphère (elles absorbent du dioxyde de carbone et rejettent de l’oxygène).</p>
<p>Une autre adaptation essentielle fut l’apparition d’un tissu vasculaire, décrit sur des fossiles de <a href="https://fr.wikipedia.org/wiki/Cooksonia">Cooksonia</a> vieux de 410 millions d’années. Analogue au système sanguin des animaux, ce tissu est constitué de cellules permettant le transport de l’eau et des nutriments absorbés par les racines. Ils sont véhiculés vers les feuilles qui produisent les glucides distribués en retour dans les tissus. La capacité d’absorber de l’eau dans le sol et de la répartir dans leurs tissus a permis aux plantes de s’adapter à des climats secs. Le réseau vasculaire a aussi constitué un tissu de soutien, une sorte de « squelette » rigide donnant leur forme aux racines, aux tiges, aux feuilles et permettant à la plante de rester érigée : il avantagea tellement les végétaux qu’ils se développèrent rapidement et dominèrent la scène.</p>
<hr>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/234678/original/file-20180903-41717-7fk3sz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/234678/original/file-20180903-41717-7fk3sz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=860&fit=crop&dpr=1 600w, https://images.theconversation.com/files/234678/original/file-20180903-41717-7fk3sz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=860&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/234678/original/file-20180903-41717-7fk3sz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=860&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/234678/original/file-20180903-41717-7fk3sz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1080&fit=crop&dpr=1 754w, https://images.theconversation.com/files/234678/original/file-20180903-41717-7fk3sz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1080&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/234678/original/file-20180903-41717-7fk3sz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1080&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Evolution.</span>
<span class="attribution"><span class="source">Editeur</span></span>
</figcaption>
</figure>
<p><em>Partie rédigée par Robert Snedden pour le livre « Evolution ».</em></p><img src="https://counter.theconversation.com/content/102595/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Steve Parker est le coordinateur de l'ouvrage d'où est tiré l'extrait publié.</span></em></p>
Quand la vie, sortie des océans, a-t-elle gagnée la terre ? Un extrait du livre « Evolution » qui paraît ce jour aux éditions Delachaux & Niestlé.
Steve Parker, Zoologist, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/81338
2017-08-09T17:08:14Z
2017-08-09T17:08:14Z
Fences are an increasing threat to Africa’s migratory wildlife
<figure><img src="https://images.theconversation.com/files/181372/original/file-20170808-10926-wuf5ra.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">In the Serengeti wildebeest will move more than 2000km during their annual migration.</span> <span class="attribution"><span class="source">Sarah Durant</span></span></figcaption></figure><p>Wildebeest rarely stay still for long. With sloping hindquarters, and an easy loping gait, their bodies are designed to move. In the Serengeti ecosystem, for instance, a wildebeest will move over more than 2,000 kilometres during their annual migration.</p>
<p>Migratory or nomadic animals, like wildebeest, that live in drylands need to move over vast distances to find sufficient water and nutrients. They <a href="http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12415/full">follow</a> localised and variable rainfall and food resources.</p>
<p>The Serengeti wildebeest spends the wet season, November to April, on the short grass plains of the southern Serengeti National Park and adjoining Ngorongoro Conservation area in Tanzania. Here they feed on nutritious grass shoots that grow in response to the abundant rain. But even here, they do not stay still. They constantly move across the short grass plains in search of the fresh grass that grows after each new rainfall. This <a href="https://books.google.co.uk/books?id=VjPBBwAAQBAJ&amp;lpg=PA125&amp;ots=gYWKcivTs7&amp;dq=wildebeest%20calving%20peak&amp;lr&amp;pg=PA125#v=onepage&amp;q=wildebeest%20calving%20peak&amp;f=false">allows</a> mothers to maximise milk production for their calves, born during a simultaneous calving of more than a quarter a million, peaking in February.</p>
<p>When the rains cease at the end of April, the wildebeest start their long journey to their dry season grazing areas. They first move west, and then head north, following the remaining water in the rivers before moving on as they dry out. Eventually they reach the only permanent water found in the Mara River on the Kenyan border. The dry season is hard, and many wildebeest die of starvation during this period.</p>
<p>When the rains start in November, the wildebeest lope down south once again. They make the journey to the short grasslands nearly 200km away in just a few days. Here they graze, recover their strength and the cycle begins again.</p>
<p>If these Serengeti wildebeest were to face a barrier at any point in their journey, they would die, either of starvation or thirst. Sadly, this has happened to migratory animals elsewhere in Africa. For example, over 30 years ago, <a href="http://www.int-res.com/articles/esr2009/7/n007p055.pdf">after a fence</a> was erected as a veterinary cordon to separate wildlife from cattle in the Kalahari, 80,000 wildebeest and 10,000 hartebeest died when they were no longer able to access permanent water during a drought. The fence was built to satisfy European Union livestock disease regulations, and allow southern African countries to export meat into the European Union.</p>
<p>Unfortunately, the ability of wildlife in Africa to continue to move across landscapes is still being threatened by linear barriers, and this is particularly a problem in Africa’s drylands.</p>
<h2>African drylands</h2>
<p>African drylands are home to most of its large mammal species. These include semi-arid and arid savannahs, found across much of eastern and southern Africa, which support spectacular wildlife migrations, such as those found in the Serengeti. But drylands also include hyperarid deserts, such as the vast Sahara, home to distinctive nomadic species such as the critically endangered Addax and dama gazelle.</p>
<p>Because mobility is key for large mammals in these systems, subdividing land reduces the numbers of animals areas can support. To the extent that 300km2 of land in Laikipia <a href="http://www.tandfonline.com/doi/abs/10.2989/10220110409485847">will support</a> 19% fewer cattle if subdivided into 10km2 parcels.</p>
<p>Large carnivores, which depend on wide-ranging herbivore prey, also need to range widely, and live at even lower densities than their prey. The Saharan cheetah, for example, <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0115136">occurs at</a> one of the lowest densities ever documented for a big cat, with only one individual per 4,000km2.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/181377/original/file-20170808-22953-1tkwm43.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/181377/original/file-20170808-22953-1tkwm43.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/181377/original/file-20170808-22953-1tkwm43.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/181377/original/file-20170808-22953-1tkwm43.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/181377/original/file-20170808-22953-1tkwm43.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/181377/original/file-20170808-22953-1tkwm43.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/181377/original/file-20170808-22953-1tkwm43.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"></span>
<span class="attribution"><span class="source">Sarah Durant</span></span>
</figcaption>
</figure>
<p>The recent human migration crisis and growing insecurity in many dryland areas across the Sahara-Sahel <a href="http://frontex.europa.eu/assets/Publications/Risk_Analysis/AFIC/AFIC_2016.pdf">has led to</a> calls for large-scale border fencing in Africa, some of which stretch over several hundreds of kilometres.</p>
<p>There are also growing calls for large scale boundary fencing of protected areas as well as infrastructure developments, such as oil pipelines and railways, that cut across wildlife movement pathways. Kenya’s new <a href="http://www.nation.co.ke/oped/Opinion/ouma-likely-negative-consequences-sgr-construction-wildlife/440808-3952294-lc7xn5/index.html">Standard Gauge Railway line</a> is a recent example.</p>
<p>On top of this is the problem of boundary fences erected around smaller plots of land. In southern Kenya fences put up around private farms have <a href="http://www.fao.org/docrep/012/i1048e/i1048e04.pdf">meshed together</a> to form a large-scale barrier to wildlife movement.</p>
<h2>International action</h2>
<p>In the face of these pressures, migratory, nomadic and wide ranging species depend on trans-boundary action for their long term survival.</p>
<p>The <a href="http://www.cms.int/">UN Convention on the Conservation of Migratory Species of Wild Animals </a>, also known as the Bonn Convention, lays the legal foundation to safeguard species that need to move across international boundaries. It also provides for internationally coordinated conservation measures throughout their migratory range.</p>
<p>Africa is not alone in facing barrier threats. In central Asia, linear barriers also threaten this region’s migratory wildlife. For example, the border fence and railroad between Kazakhstan and Uzbekistan <a href="http://onlinelibrary.wiley.com/doi/10.1111/reel.12169/full">bisects</a> the Saiga antelope migration between these countries. It has helped to put this population on the brink of extinction.</p>
<p>In response to barrier threats, the Convention on the Conservation of Migratory Species established the <a href="http://www.cms.int/en/legalinstrument/central-asian-mammals-initiative-0">Central Asian Mammals Initiative</a> This produced an important set of guidelines to inform fencing interventions and to help sustain migration corridors for migratory ungulates in Asia.</p>
<p>These guidelines are now being followed up with action. A project has been initiated to partially remove and modify the fences along the Trans-Mongolian Railway. This had formed a major barrier to movement for kulan (wild ass) and Mongolian gazelles. Furthermore, border fence modifications <a href="http://www.cms.int/en/publication/saiga-crossing-options">recommended</a> by the Bonn Convention on the Conservation of Migratory Species are being implemented to enable Saiga to move, once again, between Kazakhstan and Uzbekistan.</p>
<h2>African issues on the table</h2>
<p>The Bonn Convention on the Conservation of Migratory Species has <a href="http://www.cms.int/en/meeting/second-meeting-sessional-committee-cms-scientific-council-scc-sc2">just held</a> the Second Meeting of the Sessional Committee of its Scientific Council. This is in the run up to the Conference of the Parties in October where countries will come together to agree on new actions to save migratory species. Under discussion was a new African Carnivore Initiative, <a href="http://www.cms.int/en/document/joint-cms-cites-african-carnivores-initiative">which seeks</a> to develop a framework for the trans-boundary conservation of existing Bonn Convention listed large carnivore species, cheetah and African wild dog, and to add two as yet unlisted species, lion and leopard, to the initiative.</p>
<p>Also on the table was an important <a href="http://www.cms.int/sites/default/files/document/cms_cop12_doc.24.4.11_addressing-connectivity_e.pdf">new initiative</a> to maintain connectivity for terrestrial species, including an additional decision <a href="http://www.cms.int/sites/default/files/document/cms_cop12_doc.24.4.11_add1_e.pdf">requested</a> by the Zoological Society of London to address the problem of linear barriers in Africa, building on the experiences under the Central Asian Mammals Initiative.</p>
<p>If Africa to avoid catastrophic impacts of large scale fencing on its wildlife in the future, we must avoid repeating past mistakes. This <a href="http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12415/full">will require</a> further scientific research to better understand potential negative impacts of fencing and other linear barriers, and how best to mitigate such impacts, not just for wildlife, but also for ecosystem services and local communities.</p>
<p>At the Bonn Convention’s next Conference of Parties, nations will need to decide whether to implement important decisions to safeguard migratory species, including maintaining terrestrial connectivity. The fate of many wide ranging species hangs in the balance, and depends on governments supporting and, importantly, implementing, these decisions.</p><img src="https://counter.theconversation.com/content/81338/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sarah Durant receives funding from the Howard G Buffett Foundation, the Wildlife Conservation Society and St Louis Zoo's WildCare Institute. She is an Assoicate Editor for the Journal of Applied Ecology, a member of the IUCN/SSC Cat and Canid Specialist Groups and sits on Panthera's Scientific Council.</span></em></p>
Many mammals depend on large areas and trans-boundary conservation for their survival. When this is obstructed it can have a catastrophic impact on animal populations.
Sarah Durant, Senior Research Fellow, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/77486
2017-05-17T19:27:02Z
2017-05-17T19:27:02Z
The Hirola is the world’s rarest antelope. Here’s how it can be saved
<figure><img src="https://images.theconversation.com/files/169307/original/file-20170515-6990-112ptdw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Hirola has a global population size of 500.</span> <span class="attribution"><span class="source">Abdullahi H. Ali</span></span></figcaption></figure><p><em>The <a href="http://www.iucnredlist.org/details/6234/0">Hirola</a>, endemic to north-east Kenya and south-west Somalia, is the world’s most endangered antelope. It faces huge survival challenges but all is not lost. The Conversation Africa’s Samantha Spooner asked Abdullahi Ali about his research and what he thinks can be done to save this rare species.</em></p>
<p><strong>What is a hirola, where is it found and how many are there?</strong></p>
<p>The hirola is a rare medium size antelope that can weigh up to 118kg. It’s tawny or tan brown in colour and has long, sharp horns. </p>
<p>The current population of the hirola is estimated at less than 500. This small population is found within its native range, restricted to communal lands along the Kenya-Somalia border with no formal protection. The highest numbers are in Ijara and Garissa County, Kenya. </p>
<p>The hirola is the only surviving member of the genus <a href="http://www.iucnredlist.org/details/6234/0">Beatragus</a> and there are none in captivity. </p>
<p><strong>The hirola is known as the “world’s most endangered antelope”. What factors caused this?</strong></p>
<p>With a global population size of 500, the hirola is <a href="http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12856/full">considered</a> to be the world’s most endangered antelope. This is <a href="https://www.cambridge.org/core/journals/oryx/article/div-classtitlepopulation-and-habitat-assessment-of-the-critically-endangered-hirola-span-classitalicbeatragus-hunterispan-in-tsavo-east-national-park-kenyadiv/E98E178901F73C5C16066762CBECBC9F">the smallest</a> known number of an antelope species and its population has been reducing rapidly since the 1970s.</p>
<p>Several factors caused this. <a href="http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.695.5896&rep=rep1&type=pdf">In the 1980s</a>, rinderpest – a viral disease – <a href="http://coastalforests.tfcg.org/pubs/Hirola%20Evaluation%20Report.pdf">killed</a> about 85-90% <a href="http://www.nrt-kenya.org/news-list/6/20/2016-hirola-update">of the</a> existing 15,000 hirola, along with other wildlife. When the disease was eradicated in the early 1990s, the hirola populations didn’t bounce back. </p>
<p>In my <a href="http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12856/full">recent study</a>, my colleagues and I identified a combination of additional factors that kept their numbers low, and decreasing. </p>
<p>Firstly, hirola are a grassland species. Therefore, overgrazing by both livestock and other wildlife have led to a loss of food for the hirola in its native range. </p>
<p>The loss of elephants from hirola habitat, due to <a href="http://www.poachingfacts.com/poaching-statistics/elephant-poaching-statistics/">massive poaching</a>, also contributed significantly to the encroachment of trees into grasslands and led to reduced grasses for them to eat. Elephants control forestation as they uproot, break or eat trees. In their absence, <a href="http://nature.berkeley.edu/getzlab/dissertation/BaxterDis.pdf">trees increase</a> relative to grass cover.</p>
<p>Similarly, there used to be frequent bush fires, which contributed to a balance between tree cover and grassland. These were frequently used by locals but became suppressed by government policy. </p>
<p>Another key factor responsible for their low numbers is predation by carnivores. Lions, cheetahs, wild dogs and leopards pose a significant threat to the already diminishing hirola population. With such a low population, the survival of every individual counts. In many situations predators target mothers and their calves. This is because after calving, the female and her calf will temporarily disassociate from groups making them easier prey. </p>
<p>Finally, several droughts <a href="http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.695.5896&rep=rep1&type=pdf">have occurred</a> in the hirola’s range which also led to many deaths. </p>
<p><strong>Why has their conservation and recovery been so difficult?</strong></p>
<p>The conservation and recovery of hirola has been difficult for a variety of reasons. </p>
<p>Language, religious and ethnic differences between conservationists and the Somalis living in Eastern Kenya, have led to suspicion and mistrust. This limits conservation efforts to opportunistic field visits by outsiders rather than a long-term, sustainable project. </p>
<p>Insecurity is also a big problem in parts of eastern Kenya – this includes the hirola’s rangeland. These areas have been volatile since independence <a href="https://www.researchgate.net/profile/Otunnu_Ogenga/publication/242253273_Factors_Affecting_the_Weatment_of_Kenyan-Somalis_and_Somali_Refugees_in_Kenya_A_Historical_Overview/links/0c960535049fb824cc000000.pdf">due to</a> banditry activities from across the border and conservationists have shied away from these areas. </p>
<p>Another barrier to conservation is the neglect of this region by the government. The area is marginalised and has poor infrastructure which makes it <a href="http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12856/full">difficult</a> to establish conservation projects or protected areas for the hirola. </p>
<p>A final, major factor is competition for pasture and other resources between the communities in the area, who rely on livestock, and the wildlife. This leads to apathy for conservation and a lack of participation by locals in recovery efforts.</p>
<p>*<em>What can be done to save them? *</em></p>
<p>Based on my <a href="http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12856/full">research</a> I believe that the following measures would help save the hirola:</p>
<ul>
<li><p>Since there is a link between community livelihoods and hirola habitat, conservation projects must be supported by local communities. Trained, local scientists should be encouraged to take the lead in these. Communities are more likely to embrace conservation as a form of land-use if it’s not led by outsiders.</p></li>
<li><p>More protected areas should be created and existing sites need restoration. A part of this includes the restoration of the Arawale National Reserve which is at the centre of the hirola’s geographic range. This is a government protected area in Garissa County that used to thrive but has been neglected since 1982. </p></li>
</ul>
<p>Because of the massive tree encroachment in the area that reduced grasslands, I also recommend:</p>
<ul>
<li><p>Manual tree removal, to reduce tree encroachment on grassland, and native grass reseeding to increase food for the hirola</p></li>
<li><p>Voluntary reduction in livestock numbers to minimise overgrazing and competition between hirola and livestock </p></li>
<li><p>Community-based protection of elephants – in the form of anti-poaching squads and enhanced communication between villages – so that elephant herds can be safe on community land</p></li>
<li><p>Finally, there’s a big need for sustained funding. Conservation efforts tend to focus on other species in Kenya.</p></li>
</ul><img src="https://counter.theconversation.com/content/77486/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>My work was made possible by the support of the Kenya Wildlife Service, communities in Ijara and Fafi sub-counties of Garissa County, Garissa County officials, Ishaqbini Community Conservancy, Northern Rangelands Trust, Association of Zoos and Aquariums, British Ecological Society, Chicago Zoological Society, Denver Zoo, Disney Worldwide Conservation Fund, Houston Zoo, Idea Wild, International Foundation for Science, IUCN/SSC Antelope Specialist Group, Mohamed Bin Zayed Species Conservation Fund, National Museums of Kenya, People’s Trust for Endangered Species, Rufford Foundation, St. Louis Zoo’s Center for Conservation in the Horn of Africa, University of Wyoming’s Berry Biodiversity Conservation Center, University of Wyoming’s Haub School, and the Zoological Society of London. </span></em></p>
Elephants, livestock and grass all play an important role in ensuring the survival of the Hirola - the world’s rarest antelope.
Abdullahi Ali, Fellow, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/77332
2017-05-16T00:13:47Z
2017-05-16T00:13:47Z
Using dogs to find cats: overcoming the challenges of tracking cheetahs
<figure><img src="https://images.theconversation.com/files/169327/original/file-20170515-6981-14uwge8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Detection dog Pepin, with his trainer, Megan Parker, on the search for scat © Sarah Durant
</span> </figcaption></figure><p>Cheetahs are Africa’s rarest big cat. Only <a href="http://www.pnas.org/content/114/3/528">an estimated</a> 7,000 individuals are thought to survive in the wild. They’re spread across 32 populations covering a vast area of more than 3 million square kilometres. Cheetah densities are <a href="https://academic.oup.com/mbe/article-lookup/doi/10.1093/molbev/msr048">never higher</a> than two or three cheetahs per 100km2 and <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0115136">can be as low</a> as one cheetah per 4,000km2. Lion density <a href="https://africageographic.com/blog/the-highest-density-of-lions-in-africa/">can be</a> up to about 16.85 lions per 100km2. What’s more, in areas where cheetahs are persecuted, due to conflict with livestock and game keepers, they may flee before you are ever likely to even see them.</p>
<p>Cheetahs’ rarity and elusiveness poses a problem for conservationists. To conserve the species, we need to know where they still persist, and whether their numbers are increasing or decreasing. But how can we quickly and cheaply estimate their abundance? </p>
<p>Over more than two decades of studying and conserving cheetahs, I have tried many ways of counting them. I have tried simply looking for cheetahs and individually identifying them. This works well. But it requires cheetahs that don’t flee from vehicles, an open habitat – and a lot of time and patience. In short, this approach only works on the Serengeti plains and has been key to our long-term <a href="https://www.zsl.org/cheetah-conservation">Serengeti Cheetah Project</a> which has gathered information on individually known cheetah for decades. </p>
<p>I have tried counting spoor – cheetah footprints left in the dust of dirt roads. <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2009.00682.x/full">Even in</a> the Serengeti, where cheetah densities are at their highest, I had to drive an average of 50km to find just a single spoor. At least 30 such observations are needed for a reliable density estimate. </p>
<p>Remote <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4309643/">camera traps</a> can also work in some circumstances and <a href="https://www.ncbi.nlm.nih.gov/pubmed/26200660">citizen science</a> in tourist areas. But none of these methods work across different habitats, and all need substantial infrastructure and considerable investment in time.</p>
<p>Could the answer to finding cheetah lie with another animal? Dogs have some of the <a href="https://www.medicaldetectiondogs.org.uk/the-dogs-nose/">world’s most</a> sensitive snouts. We put these <a href="http://onlinelibrary.wiley.com/doi/10.1111/jzo.12445/full">to the test</a> in a remote corner of Zambia.</p>
<h2>The importance of poop</h2>
<p>One of the things dogs can sniff out very successfully – as any canine’s owner will know – is poop.</p>
<p>But poop has important properties beside smell. Food, as it passes through the digestive tract and rectum, accumulates DNA from the intestinal and rectal walls, which becomes embedded within the poop. This DNA is a unique genetic signature of individuals. Therefore if you can find cheetah scat, you can extract DNA and identify the genotype of that individual. </p>
<p>Cheetahs defecate at least once a day, hence cheetah scat should occur across a landscape more frequently than the cheetah themselves. It follows that, if you can find enough scat and extract DNA from it, you may be able to estimate the numbers of individual cheetah in the population. Finding scat, rather than cheetah, has the added advantage in that scat doesn’t run away.</p>
<p>So far, so good. But there is a flaw in this plan. Cheetahs, who are largely non territorial, don’t defecate in nice, easy to find, prominent locations. As a result, their scat is extremely difficult to detect. </p>
<h2>Harnessing the power of the canine snout</h2>
<p>This is where the poop-detecting power of the canine snout comes into play. Domestic dogs are increasingly playing an important role in conservation. Organisations such as <a href="http://wd4c.org/">Working Dogs for Conservation</a>, and <a href="http://www.greendogsconservation.com/">Green Dogs</a> specialise in training domestic dogs for conservation work. They harness the dogs’ natural poop detection ability, by training them to find poop of a particular species, signal their trainer when they have found it, and, above all, resist the temptation to eat any poop they find.</p>
<p>Could domestic dogs be the key to counting cheetah? Together with my colleagues from the <a href="http://www.zambiacarnivores.org/">Zambian Carnivore Programme</a> and the Zambia Department of National Parks and Wildlife, we teamed up with Working Dogs for Conservation and Green Dogs to put domestic dogs to the test. This is what brought a team of large carnivore conservationists, two dogs (Faust and Pepin) and their trainers to a remote corner of western Zambia, where a low density, but unknown, population of cheetah still survives in and around the Liuwa Plain National Park.</p>
<h2>Disappearing poop</h2>
<p>At first, the dogs struggled to find scat on our pre-designated dog walking transects. This was when we started to notice the conspicuous absence of the dogs’ poop around our camp. On closer inspection, we were alarmed to discover that, no sooner had a new deposition of poop been made, a small army of <a href="https://theconversation.com/five-things-dung-beetles-do-with-a-piece-of-poo-47367">dung beetles</a> appeared and started rolling it away in large bundles. </p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/168708/original/file-20170510-28069-uxyes3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/168708/original/file-20170510-28069-uxyes3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=829&fit=crop&dpr=1 600w, https://images.theconversation.com/files/168708/original/file-20170510-28069-uxyes3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=829&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/168708/original/file-20170510-28069-uxyes3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=829&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/168708/original/file-20170510-28069-uxyes3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1042&fit=crop&dpr=1 754w, https://images.theconversation.com/files/168708/original/file-20170510-28069-uxyes3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1042&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/168708/original/file-20170510-28069-uxyes3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1042&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Pepin observes a dung beetle scurrying away with a substantial amount of poop © Dave Hamman.</span>
</figcaption>
</figure>
<p>A large healthy pile of steaming dog poop could disappear completely in a matter of hours. Having been an observer of cheetah poop in the Serengeti over many years, this was a first for me, and it caused me a substantial amount of anxiety.</p>
<p>Fortunately, as the dogs moved south, they started to find cheetah scat laden with bone and hair. This, presumably, was much less appealing to a passing dung beetle.</p>
<p>In fact, the dogs turned out to be very successful at finding cheetah scat. In all, they found 27 scats over a survey area of 2,400km2. Humans, on similar transects looking for spoor, found none. This neatly demonstrated the superiority of the canine snout over the human eye when it came to detecting the presence of cheetah.</p>
<h2>Estimating population size</h2>
<p>These scats were combined with a number of opportunistically collected scat. The DNA extracted from the scat samples were of poor quality, and so interpreting the genotypes wasn’t always easy. </p>
<p>However, we were able to <a href="http://onlinelibrary.wiley.com/doi/10.1111/jzo.12445/full">generate an estimate</a> of between 17-19 cheetah in the area, with a density of 6-7 individuals per 1000km2. The preliminary estimate of genetic effective population size was low, at just 8-14 individuals, and requires further investigation.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/168899/original/file-20170511-32593-12c56kq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/168899/original/file-20170511-32593-12c56kq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=846&fit=crop&dpr=1 600w, https://images.theconversation.com/files/168899/original/file-20170511-32593-12c56kq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=846&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/168899/original/file-20170511-32593-12c56kq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=846&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/168899/original/file-20170511-32593-12c56kq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1063&fit=crop&dpr=1 754w, https://images.theconversation.com/files/168899/original/file-20170511-32593-12c56kq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1063&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/168899/original/file-20170511-32593-12c56kq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1063&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A Liuwa cheetah © Jassiel M’soka.</span>
</figcaption>
</figure>
<p>Many areas where cheetah still survive are remote and difficult to access. Prior to this study, there were no viable methods for obtaining reliable information on cheetah abundance in most of these areas. The beauty of using detection dogs was that surveys could be conducted on foot, and the whole survey took not much more than three weeks, although genetic work could take substantially more time. </p>
<p><a href="http://onlinelibrary.wiley.com/doi/10.1111/jzo.12445/full">Our study</a>, therefore, provides an important step forward in our ability to detect cheetahs across large landscapes, monitor them and assess population trends. Such information is critical for mobilising conservation action and resources to halt the global decline of this elusive and secretive big cat.</p><img src="https://counter.theconversation.com/content/77332/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This research was supported by grants from WWF-Netherlands, National Geographic’s Big Cats Initiative, Painted Dog Conservation Inc., the Angel Fund, and National Science Foundation Animal Behavior Program under IOS-1145749. One of the authors, J. M’soka, was supported by a Schink scholarship from the Wildlife Conservation Network. The St. Louis Zoo’s Wildcare Institute for supporting a pilot project leading to this study.
This work was the result of a collaboration between the Zambian Carnivore Program, Zambia Department of National Parks and Wildlife, Working Dogs for Conservation and the Range Wide Conservation Program for Cheetah and African Wild Dogs.</span></em></p>
Cheetah’s rarity and elusiveness poses a problem for conservationists who need to know where they still persist, and whether their numbers are increasing or decreasing.
Sarah Durant, Senior Research Fellow, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/71088
2017-01-11T20:14:19Z
2017-01-11T20:14:19Z
Wake-up call for the world as the plight of cheetahs worsens
<figure><img src="https://images.theconversation.com/files/152362/original/image-20170111-6447-606129.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cheetah are now restricted to less than 10% of its historical distribution, and survive in just 33 populations</span> <span class="attribution"><span class="source">Yathin/Flickr</span></span></figcaption></figure><p>Our <a href="https://newsroom.wcs.org/News-Releases/articleType/ArticleView/articleId/9456/Spring-Toward-Extinction-Cheetah-Numbers-Crash-Globally.aspx">recent report</a> on global cheetah decline provides alarming reading. Using the best available information, we estimate that there are only about 7,100 wild cheetah left in the world. </p>
<p>The species is now restricted to less than 10% of its historical distribution, and survives in just 33 populations, most of which number fewer than 100 individuals. </p>
<p>Added to this perilous predicament is the fact that most cheetah live outside protected areas. There they face multiple threats including loss of habitat and prey; conflict with livestock and game keepers; and illegal wildlife trade in live cheetah for pets and dead cheetah for skins. </p>
<p>Recent extinctions have been <a href="https://tropicalconservationscience.mongabay.com/content/v8/tcs_v8i2_513-527_Brugiere.pdf">documented</a> in western and central Africa, and there has been an estimated decline of 85% in Zimbabwe over the last 16 years. For cheetah populations where there is sufficient information, most are declining. </p>
<p>This evidence, together with ongoing pressures outside protected areas, led me and 53 co-authors to recommend that the <a href="http://www.iucnredlist.org/">International Union for Conservation of Nature Red List</a> of threatened species up-list the status of cheetah from vulnerable to endangered. </p>
<p>The worsening of the “threat status” of cheetah should act as a wake-up call. Urgent action is needed if the survival of cheetah is to be secured. To put the status of cheetah in perspective, the Serengeti National Park alone safeguards a population of over 3,000 lions – that’s nearly half the global cheetah population.</p>
<p>That there is international public support for cheetah and other iconic megafauna is beyond doubt. This is clear from the millions of international visitors who travel thousands of kilometres to see cheetah and other wildlife, and by the millions who avidly watch wildlife programmes streaming into their homes. </p>
<p>What’s missing is effective means to channel the value into local communities that bear the real costs of living with cheetah and other problematic species.</p>
<h2>Challenging to conserve</h2>
<p>Cheetah are not the largest cat – they are <a href="https://www.zsl.org/cheetah-fast-facts">less than</a> a third the weight of a lion – but they are one of the widest ranging, capable of travelling across areas in excess of 1,000 square kilometres every year. This makes them particularly challenging to conserve. </p>
<p>They move this widely to find their prey and because they need to avoid other large predators, including lion and spotted hyena, which <a href="http://beheco.oxfordjournals.org/content/11/6/624.full">may kill</a> their cubs and steal their kills. But this also means that cheetah occur at much lower densities than other big cats, sometimes seldom exceeding two for every 100 square kilometres. In the Sahara, where a critically endangered population of cheetah still survives, we have documented densities <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0115136">as low as</a> only one cheetah in 4,000 square kilometres. </p>
<p>Thus cheetah need conservation over a much larger scale than is usually seen in terrestrial conservation.</p>
<p>To halt cheetah decline we also have to confront the realities of conservation in developing countries where they still survive. Communities who share their land with cheetah may face a daily challenge just to feed themselves and their families. They cannot afford to pay the costs of losing their precious livestock to cheetah, even if this is a <a href="http://conservationmagazine.org/2016/03/poop-clears-cheetahs-livestock-murder-accusations/">relatively rare</a> event.</p>
<h2>Conservation strategies</h2>
<p>Much has already been achieved. </p>
<p><a href="https://www.zsl.org/">Zoological Society of London</a> and <a href="https://www.wcs.org/">Wildlife Conservation Society</a>’s joint <a href="http://cheetahandwilddog.org/">Range Wide Conservation Program for Cheetah and African Wild Dog</a> has been working with range state governments for nearly 10 years. They have helped to put in place regional strategies and national action plans that provide a road map for the conservation of cheetah together with African wild dogs. Wild dogs are a species with similar ecology and face similar threats to cheetah. </p>
<p>These strategies and plans have the strong support of range state governments and conservation NGOs and lay out a list of all the actions that need to be undertaken to secure the survival of both species. More financial mechanisms are needed, from
range state governments, bilateral and multilateral donors and NGOs, to implement these road maps, and we also need innovative new ways for communities to benefit from the presence of wildlife.</p>
<p>Over coming decades Africa faces a critical period for its biodiversity. The continent’s human population is <a href="http://www.euractiv.com/section/development-policy/news/africas-population-set-to-double-by-2050-says-new-report/">predicted</a> to double by 2050. The need to support and feed more people will exert unprecedented pressures on wildlife and the environment. </p>
<p>But lessons from Europe show what can be done. Here large carnivores faced imminent extinction towards the end of the 20th century. Yet today, due to protection and restoration programmes combined with policies that help foster coexistence between people and wildlife, there has <a href="https://howtoconserve.org/2016/06/10/carnivore-recovery-europe/">been a resurgence</a> of bears, wolves and lynx. </p>
<p>People and large carnivores can live together, even when human densities are relatively high.</p>
<p>For cheetah, we urgently need to find the political will and the financial means to enable people and wildlife to coexist, and for both to prosper. Only then can we be sure that future generations will be able to continue to marvel at the sight of a cheetah at full speed. If we fail, the fate of the cheetah will be in doubt.</p>
<p><em>A version of this article first appeared in the <a href="http://voices.nationalgeographic.com/2016/12/28/halting-global-cheetah-decline/">National Geographic Cat Watch blog</a></em></p><img src="https://counter.theconversation.com/content/71088/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This study was supported by the Howard G Buffett Foundation, the Association of Zoos and Aquariums Safeguarding Animals From Extinction (AZA SAFE) and the National Geographic’s Big Cats Initiative.</span></em></p>
A new study reveals that just 7,100 cheetahs remain globally, representing the best available estimate for the species to date.
Sarah Durant, Senior Research Fellow, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/66283
2016-10-11T18:03:34Z
2016-10-11T18:03:34Z
Mosquito nets are often used for fishing. A smart response is needed
<figure><img src="https://images.theconversation.com/files/140876/original/image-20161007-21416-1fwy4yt.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Malaria nets are being used as fishing nets in some parts of Africa.</span> <span class="attribution"><span class="source">Emma Bush</span></span></figcaption></figure><p>The human race is extremely resourceful, particularly when resources are limited. Inevitably, when poor rural communities are given access to a new asset they will find a number of uses for them. Anti-malarial bednets - the fine-mesh nets used to protect people from mosquito bites <a href="https://www.againstmalaria.com/WhyNets.aspx">while they sleep</a> – are a good case in point.</p>
<p>Nearly half a million people die of malaria each year, <a href="http://www.who.int/malaria/media/world-malaria-report-2015/en/">90% of whom live in Africa</a>. This number has come down dramatically since the turn of the century. Between <a href="http://www.who.int/malaria/media/world-malaria-report-2015/en/">2000 and 2015</a> major international interventions, including the distribution of mosquito nets, has resulted in a 42% reduction in new malaria cases and a 66% fall in malarial mortality. </p>
<p>More than 290 million mosquito nets were <a href="https://www.cdc.gov/malaria/malaria_worldwide/reduction/itn.html">distributed</a> in sub-Saharan Africa between 2008 and 2010. </p>
<p>Mosquito nets are being used in pest protection for plants, <a href="http://www.thetimes.co.uk/tto/news/world/africa/article4506843.ece">chicken coops</a>, rope, <a href="http://www.nytimes.com/2015/01/25/world/africa/mosquito-nets-for-malaria-spawn-new-epidemic-overfishing.html?_r=0#">football goals</a> and <a href="https://www.naij.com/930716-haaaa-brides-wedding-dress-will-make-look-twice-photo.html">wedding veils</a>. They are also being used as fishing nets, which is the focus of this article. </p>
<p>Some view mosquito-net fishing <a href="http://www.nytimes.com/2015/01/25/world/africa/mosquito-nets-for-malaria-spawn-new-epidemic-overfishing.html?_r=0">as a growing problem</a>. There are those who point out that using them for fishing is <a href="http://www.thetimes.co.uk/tto/news/world/africa/article4506843.ece">misuse</a> because they were distributed to manage malaria.</p>
<p>Fishing with mosquito nets is also widely considered to be environmentally destructive and <a href="http://www.nytimes.com/2015/01/25/world/africa/mosquito-nets-for-malaria-spawn-new-epidemic-overfishing.html?_r=0">a threat to fish</a>. A number of countries, including <a href="http://www.mifugouvuvi.go.tz/wp-content/uploads/2012/12/ANNUAL-STATISTICS-REPORT-2013.pdf">Tanzania</a>, <a href="http://www.oceandocs.org/bitstream/handle/1834/297/FishAct-Kenya1991.pdf;jsessionid=333B442D42524AE707B8C830BBD1BBBA?sequence=1">Kenya</a> and <a href="http://c-3.org.uk/c3-madagascar-raising-awareness-of-fishing-regulations-in-nosy-hara/">Madagascar</a>, have tried to control the use of nets by imposing restrictions on the mesh size that can be used.</p>
<p>It’s easy to criticise poor communities for the misuse of this resource. But for a family, securing protein today may trump preventing malaria tomorrow.</p>
<p><a href="http://onlinelibrary.wiley.com/doi/10.1111/conl.12286/full">Our quantitative study</a> on the coast of Kenya shows that while mosquito net fishing is locally common, it may not always affect malaria protection.</p>
<h2>A coastal Kenyan case</h2>
<p>We interviewed senior family members from traditional Giriama homesteads in a coastal community in Kenya. We found fishing with mosquito nets to be common – involving 50% of households surveyed. The majority of fishers were male, busting previous assumptions that women largely used this method.</p>
<p>People used the nets to catch young fish and prawns to eat at home and sell on, playing an important role in their livelihoods. </p>
<p>Fishers at the site reported using old or surplus mosquito nets. As a result, bednet coverage was no different between families fishing with mosquito nets and those not.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/140845/original/image-20161007-8972-19noslu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/140845/original/image-20161007-8972-19noslu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/140845/original/image-20161007-8972-19noslu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/140845/original/image-20161007-8972-19noslu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/140845/original/image-20161007-8972-19noslu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/140845/original/image-20161007-8972-19noslu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/140845/original/image-20161007-8972-19noslu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/140845/original/image-20161007-8972-19noslu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mosquito nets are distributed in Africa to fight malaria but often people find other uses for them.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>We discussed with the participants what fishing with mosquito nets means to their families. They cited the provision of food and income, and the ease of use. But they also expressed concern about the potential impact on the fishery from toxic insecticides and the capture of small and juvenile fish. </p>
<p>They also commented on the allure of the method to new fishers and the extra pressure it brought to the fishing sector. As traditional farmers, the Giriama only started fishing seriously in recent years. Fishing with mosquito nets is low-cost and low-skilled work that can be done in shallow water, not requiring capital investment or ocean experience.</p>
<h2>The conservation problem</h2>
<p>The simple use of an available net by fishers has become a classic conservation problem involving numerous interested parties.</p>
<p>The health sector goal is to achieve <a href="http://www.who.int/malaria/areas/global_targets/en/">global anti-malarial targets</a>. The fear is that anti-malaria nets being used for other purposes will mean the targets aren’t <a href="https://malariajournal.biomedcentral.com/articles/10.1186/1475-2875-7-165">met</a>.</p>
<p>Fisheries managers believe use of the nets could damage fish stocks. They believe that fine-meshed netting is not selective and catches juvenile fish before they can grow or breed. In addition, the nets are treated with toxic insecticides.</p>
<p>While local communities report declines in the abundance and size of fish, explicit links of cause and effect remain in the research pipeline. </p>
<p>Whatever the impact, outright bans on fishing with mosquito nets based on mesh-size are likely to be extremely difficult to enforce and potentially harmful to families now reliant on the practice.</p>
<h2>What next?</h2>
<p>As mosquito nets continue to be distributed to poor communities mosquito net fishing is not likely to disappear. A contributing factor is that the current net distribution system does not consider safe and sustainable disposal of nets. </p>
<p>At the coastal site in Kenya, mass distributions have resulted in one net for every two people. We concluded that use of old or spare nets for fishing mediated potential negative effects on malaria prevention. People were able to use new nets to sleep under and old or spare nets for fishing.</p>
<p>But this relationship is likely to be <a href="https://www.cambridge.org/core/journals/parasitology/article/when-they-dont-bite-we-smell-money-understanding-malaria-bednet-misuse/DB7525CD0B990B74F225D7DF780D7BDE">scenario-dependent</a>. In another case, a similar level of net saturation might result in several fishers per household, or if nets are few, might lead to trade-offs between fishing and anti-malaria protection. How poor must you be before the net on your bed is better for you in the sea?</p>
<p>It is likely that mosquito net fishing happens wherever mosquito nets and small-scale fisheries meet. We urgently need to grapple with the big questions around this issue: Is fishing with mosquito nets a threat to anti-malarial efforts? Is it a threat to food security? What are the real ecological consequences? How much do local communities depend on it for food and income? </p>
<p>Only a highly coordinated, inter-disciplinary effort by all key stakeholders, and additional research, will address the problem.</p><img src="https://counter.theconversation.com/content/66283/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Emma Bush received funding from the Tropical Agriculture Association and currently receives funding from an Impact Collaborative Research Studentship between the University of Stirling and Gabon National Parks Agency.</span></em></p><p class="fine-print"><em><span>Rebecca Short receives funding from the Natural Environment Research Council, UK. </span></em></p>
The simple use of a net intended to curb malaria by fishers has become a classic conservation problem.
Emma Bush, PhD Research Student, University of Stirling
Rebecca Short, PhD Student, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/42372
2015-05-28T12:28:05Z
2015-05-28T12:28:05Z
Opportunity knocks for the Tories to boost gender equality in science
<figure><img src="https://images.theconversation.com/files/83098/original/image-20150527-4857-mo6srt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Inspiring role models can help more girls consider a career in science.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/wwworks/3058182308/in/photolist-5EeZ4b-pwXxhP-aC4thv-7MHw2c-ei1Weu-3tEAPw-dSE67-nLuPZ-8rU6Cf-8GYqss-qtHwNH-qtEgKE-aYq8xk-qyeqic-qs3Qhc-7NVd6E-gsbvVa-5G7y9S-4DgdN4-r88Cz5-pwXrDp-azHS41-bTU7FK-5G7xDs-6XN7KH-53fHVh-5M3ikd-cztY1y-6EY3zN-seAW5K-crLycj-crPobC-dupwpS-crLxUN-sey4Eg-qcaa2m-qcgkEx-68kqhA-rVgQV4-qtx6j2-crKWef-crJg7u-crP7NQ-83Ps6w-crN4HJ-7NRfyZ-4v29tN-rixJvh-phCkkD-crLQHm">woodleywonderworks/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>It’s no secret that there is a lack of women in science-related careers. And it’s bad for the economy. While the Conservatives launched <a href="https://www.gov.uk/government/news/400-million-will-help-science-and-engineering-students-get-ahead-in-the-global-race-and-encourage-more-women-to-study-these-subjects">some good initiatives</a> to address this problem in the last coalition government, their polices were disjointed and did not result in any significant progress. The party should now grasp the opportunity to tackle the problem properly – linking policies on education, career progression and childcare. </p>
<p>The UK <a href="http://www.elsevier.com/about/press-releases/science-and-technology/uk-continues-to-punch-above-its-weight-in-the-research-arena">punches above its weight</a> when it comes to science. Despite this, we are missing out on a huge amount of talent, as 50% of the population is heavily under-represented in the discipline. The statistics are horrific: <a href="https://www.wisecampaign.org.uk/resources/2012/12/uk-statistics-2012">only 13%</a> of all science, technology, engineering and mathematics (STEM) jobs in the UK are occupied by women despite equal gender representations at A level and undergraduate level for many STEM disciplines.</p>
<p>Across the whole of academia, women occupy <a href="http://ec.europa.eu/research/science-society/document_library/pdf_06/she-figures-2012_en.pdf">only 17.5% of the top academic positions</a> in the UK, which is below the average proportion for the EU. <a href="http://www.timeshighereducation.co.uk/news/gender-survey-of-uk-professoriate-2013/2004766.article">Several universities</a> are falling well short of that already low benchmark. The situation is even worse in the UK’s natural sciences and engineering and technology, where <a href="http://ec.europa.eu/research/science-society/document_library/pdf_06/she-figures-2012_en.pdf">only 7-9% of professors are women</a>. </p>
<p>Recent research shows that a diverse scientific workforce is <a href="http://www.royalsoced.org.uk/1027_Report.html">more creative and better performing</a> than a homogeneous one. Such diverse organisations <a href="http://sciencecampaign.org.uk/CaSEDiversityinSTEMreport2014.pdf">perform better</a> financially, recruit from a wider talent pool, suffer lower staff turnover and increase creativity and problem solving capability. </p>
<h2>Linking policies</h2>
<p>There are three key areas that the next government will need to tackle to make progress on this. </p>
<p>Arguably the most important one is education. As highlighted by the former, Conservative science minister Greg Clark, <a href="https://www.youtube.com/watch?v=vmPffZ6izpY&list=PLWxZBtZEMeZBg7pNrIgKV-W_qTCaFrdw7&index=7">bringing the next generation onboard</a> is a key priority for UK science to prosper in the future. However, what was missed by the Conservatives is that we need to boost support for girls not only to consider an education in STEM subjects, but also to persist in the pursuit of a career. </p>
<p>One of the most important factors here is the low level of confidence among girls when it comes to science and maths, which has been recorded in a number of <a href="http://www.bbc.co.uk/news/education-31733742">studies</a>. Targeted action in schools is therefore needed to provide girls with inspirational role models and to boost their confidence, which is especially important in mixed gender schools. </p>
<p>Another crucial area is career progression. While some women may leave science for perfectly good reasons, there is no doubt that others leave because they don’t feel valued and think they’re not good enough. <a href="http://www.pnas.org/content/109/41/16474.full.pdf">Research has shown</a> that universities presented with two equally good CVs – one from a man and one from a woman – were more likely to want to hire the man. Most scientists are horrified to learn of their own personal bias; raising awareness of unconscious bias and providing training to employers and managers is a quick-fix way to help scientists get over such prejudice. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/83100/original/image-20150527-4840-11wnmh3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/83100/original/image-20150527-4840-11wnmh3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=859&fit=crop&dpr=1 600w, https://images.theconversation.com/files/83100/original/image-20150527-4840-11wnmh3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=859&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/83100/original/image-20150527-4840-11wnmh3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=859&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/83100/original/image-20150527-4840-11wnmh3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1080&fit=crop&dpr=1 754w, https://images.theconversation.com/files/83100/original/image-20150527-4840-11wnmh3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1080&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/83100/original/image-20150527-4840-11wnmh3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1080&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Marie Curie made it - against the oods.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/tekniskamuseet/12835367815/in/photolist-kydBF6-dhm6Vq-oZNza8-8ysXkL-fyjRFb-fyjRuu-pYYki-fyjRJm-oZNLap-eiWpN3-eiWpMY-eiWpPC-eiQFrR-ek23cd-ek23do-9HsZot-oSNULi-cLuB6G-g9eZ2N-fHXyeQ-acpTgB-x6WQB-pYYkg-egFvvr-kp2WBC-cLuzUE-4dvCFE-cLuzML-bmXXaC-51b5Tp-F4Dtu-ggqW7-dAo97d-bzSNmr-6fLhVi-6fQtaY-54gu8p-dhmdmp-8H8P9U-fyjRCq-fyjRyq-9NSLqr-8tbgT3-moJPgw-moH6dX-moH4Hx-8t8fFe-8tbfaf-8t8dMp-8t8d26">Tekniska museet/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>The third area that the next government can have a big impact on is by providing better support for scientists who take career breaks to accommodate caring responsibilities such as parental leave. Scientific careers are in many ways more accommodating of personal commitments than other demanding jobs. The next government should embrace this, by supporting more affordable and on-site childcare for scientists. More funding opportunities should also be provided for parents returning to science after taking a few years out to raise a family. </p>
<p>But why stop there? The fact remains that women are still far more likely to take out parental leave than men, despite the fact that many men would appreciate spending more time with their children. To really boost gender equality across all careers, the government should put policies in place to encourage more men to share parental leave. </p>
<h2>Obstacles to success</h2>
<p>The next government will need to work with universities, funding agencies and research institutes to ensure women are better supported through their career path. But getting to grips with the problem will not be easy. While we know that role models, mentoring, and personal development programmes all have positive impacts on women’s careers in science – particularly on junior women – implementation will not be straightforward. </p>
<p>For example, the extra demand that mentoring puts on the diminishing number of women that are senior scientists earns them no recognition in the established programme for assessing university performance (Research Excellence Framework). In short – if academics invest in mentoring the next generation, their research “credentials” suffer. But the new government has the power to shift this imbalance. </p>
<p>A subtle, re-emphasis towards valuing mentorship and investment in the scientific workforce will help promote a more positive environment for all. One step in this direction is the implementation of the <a href="http://www.ecu.ac.uk/equality-charters/athena-swan/">Athena SWAN awards</a> – essentially badges of equality for university departments and research institutes. These awards encourage departments to set new standards for themselves to achieve in their promotion and support of equality and diversity. Mentoring is a key part of this. But we need an official way of recognising the contributions of those who invest in mentorship. </p>
<p>Perhaps the biggest challenge of all is overcoming the stereotypes and prejudices that are embedded in our culture and put women off science. The sooner we realise that women make equally good scientists as men and that men that men make equally good parents as women, the easier it will be to change things. </p>
<p>While such cultural change can take time, having the right policies in place can certainly speed things up. The next government has the power to prevent financial and intellectual loss from the UK’s scientific community, but to achieve this they will need to properly connect policies on science, education and wider societal and welfare issues.</p><img src="https://counter.theconversation.com/content/42372/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nathalie Pettorelli receives funding from the Science & Technology Facilities Council. She is the co-founder of Soapbox Science.</span></em></p><p class="fine-print"><em><span>Seirian Sumner receives funding from the Science & Technology Facilities Council. She is the co-founder of Soapbox Science.</span></em></p>
The new government should link policies on education, career progression and welfare to tackle the lack of women in science.
Nathalie Pettorelli, Research Fellow, Zoological Society of London
Seirian Sumner, Senior Lecturer in Behavioural Biology, University of Bristol
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/36388
2015-01-19T16:47:54Z
2015-01-19T16:47:54Z
Badger cull didn’t kill enough badgers to be effective
<figure><img src="https://images.theconversation.com/files/69287/original/image-20150116-5165-1ugzwy7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">You're next.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/chrisjohnbeckett/10366786873">Chris Beckett</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>In the flurry of the holiday season, many people will have missed the government’s verdict on the 2014 badger culls, <a href="https://www.gov.uk/government/publications/bovine-tb-summary-of-badger-control-monitoring-during-2014">published on December 18</a>. Farmers’ representatives have branded these recent culls “<a href="http://www.fwi.co.uk/livestock/badger-cull-trial-extension-not-needed-as-pilots-end.htm">successful</a>”, and environment secretary Liz Truss claims that they show how culling “<a href="https://www.gov.uk/government/speeches/environment-secretary-speech-at-the-oxford-farming-conference">can work to reduce disease</a>”, confirming her plan to extend this controversial approach across western England.</p>
<p>Cattle farmers have suffered terribly as a result of bovine tuberculosis (TB). Many are desperate, and would welcome a cull of badgers, which research (including <a href="http://archive.defra.gov.uk/foodfarm/farmanimal/diseases/atoz/tb/isg/report/final_report.pdf">my own</a>) has shown to be a source of infection for cattle. Sadly, a closer look at the evidence suggests that the 2014 culls bring little hope of succour.</p>
<p>Despite the environment secretary’s optimism, there is so far no evidence that these pilot culls have reduced disease. The government has <a href="http://sciencesearch.defra.gov.uk/Default.aspx?Menu=Menu&Module=More&Location=None&ProjectID=18287&FromSearch=Y&Status=2&Publisher=1&SearchText=badger&SortString=ProjectCode&SortOrder=Asc&Paging=10#Description">commissioned research</a> to estimate the impacts of pilot badger culling on cattle TB but no results have been published to date, nor are any benefits <a href="http://sciencesearch.defra.gov.uk/Default.aspx?Menu=Menu&Module=More&Location=None&ProjectID=18287&FromSearch=Y&Status=2&Publisher=1&SearchText=badger&SortString=ProjectCode&SortOrder=Asc&Paging=10#Description">anticipated</a> so soon after the start of the annual culls. Culled badgers <a href="http://www.publications.parliament.uk/pa/cm201314/cmhansrd/cm140128/text/140128w0001.htm#140128w0001.htm_wqn69">have not even been tested</a> for TB.</p>
<p>Since changes in cattle TB take so long to emerge, in the short-term the government measures culling success in terms of reduced badger numbers. This is an appropriate measure because, perversely, killing too few badgers increases cattle TB rather than reducing it. </p>
<h2>The effects of badger culling</h2>
<p>In a randomised controlled trial conducted in 1998-2007, cattle TB was <a href="http://archive.defra.gov.uk/foodfarm/farmanimal/diseases/atoz/tb/isg/report/final_report.pdf">consistently elevated</a> where culling reduced indices of badger numbers by <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2007.00353.x/abstract">10-35%</a>. By contrast, nearby farms saw gradual <a href="http://archive.defra.gov.uk/foodfarm/farmanimal/diseases/atoz/tb/isg/report/final_report.pdf">reductions</a> in cattle TB where large-scale culling reduced the same indices by <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2007.00353.x/abstract">69-73%</a>. To achieve similar benefits (and to avoid increasing cattle TB), the 2013-4 culls were intended to reduce badger numbers by <a href="http://webarchive.nationalarchives.gov.uk/20120616115816/http://archive.defra.gov.uk/corporate/consult/tb-control-measures/100915-tb-control-measures-condoc.pdf">at least 70%</a>.</p>
<p>The first two culls, conducted in 2013, clearly <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/300382/independent-expert-panel-report.pdf">failed to achieve this aim</a>. Government scientists, overseen by an independent expert panel, estimated the reduction in numbers by identifying individual badgers from hair entangled in barbed wire traps. <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/300385/ahvla-extension-efficacy.pdf">They estimated</a> that between 37 and 51% of badgers were killed in the Somerset cull zone, with between 43 and 56% killed in Gloucestershire.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/69380/original/image-20150119-14495-1feper7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/69380/original/image-20150119-14495-1feper7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/69380/original/image-20150119-14495-1feper7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=902&fit=crop&dpr=1 600w, https://images.theconversation.com/files/69380/original/image-20150119-14495-1feper7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=902&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/69380/original/image-20150119-14495-1feper7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=902&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/69380/original/image-20150119-14495-1feper7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1134&fit=crop&dpr=1 754w, https://images.theconversation.com/files/69380/original/image-20150119-14495-1feper7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1134&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/69380/original/image-20150119-14495-1feper7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1134&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">If only badgers could read.</span>
<span class="attribution"><a class="source" href="http://www.flickr.com/photos/jayneandd/4500728087/in/photostream/">jayneandd</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>For the second year of culling, the government discarded both independent oversight and the hair trapping method which had revealed the first year’s failures. Before the 2014 culls commenced, the government’s planned monitoring methods were so inadequate that I <a href="https://theconversation.com/british-government-on-the-badger-cull-ask-scientists-for-help-then-ignore-them-31435">warned</a> “any future claim that the 2014 culls have reduced badger numbers sufficiently to control TB will be completely baseless”.</p>
<p>Although ministers and farming representatives do indeed now claim success, the numbers tell a different story. There are no published estimates of the percent reductions achieved by the 2014 culls. Instead, claims of success are based on the number of badgers killed in Somerset, which <a href="https://www.gov.uk/government/publications/bovine-tb-summary-of-badger-control-monitoring-during-2014">reached the minimum target</a> required by the culling licence (the Gloucestershire cull spectacularly failed to meet its target, killing just <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/388646/annex-a1-wg-final-summary.pdf">274 badgers</a> against a <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/347536/badger-cull-setting-min-max-numbers-2014.pdf">target of 615</a>).</p>
<p>Yet the <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/347536/badger-cull-setting-min-max-numbers-2014.pdf">Somerset target</a> was derived from the lower bound on the range of possible badger numbers, rather than from the best estimate. If the estimation method was accurate, there would be a 97.5% chance that the true population size was greater than this lower bound, and hence that the target was too low. Despite having met this target, statistically it is still far more likely than not that the 2014 Somerset culls failed to reduce badger numbers by 70% as planned.</p>
<p>Simple calculations provide further evidence of ineffective culling in Somerset. Government scientists estimate that, before any culling took place, the Somerset zone contained <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/347536/badger-cull-setting-min-max-numbers-2014.pdf">between 1,876 and 2,584 badgers</a>. The total number of badgers killed (<a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/388647/annex-a2-ws-final-summary.pdf">341</a> last year plus <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/300385/ahvla-extension-efficacy.pdf">955</a> in 2013) comprises just 69% of the lowest estimate. Taking into account the fact that births and immigration would have increased badger numbers between the two culls, the population cannot have been reduced by “at least 70%” if the government’s population estimates were correct.</p>
<p><a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/347536/badger-cull-setting-min-max-numbers-2014.pdf">Government documents</a> describe Somerset’s low target as “precautionary”. But from the perspective of disease control – the justification for killing otherwise protected wildlife – it risked worsening cattle TB and was hence the opposite of precautionary. With separate <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/347536/badger-cull-setting-min-max-numbers-2014.pdf">maximum targets</a> in place to avoid killing too many badgers, the only risk reduced by a low target was the risk of a cherished project being branded a failure.</p>
<p>Failing to reduce badger populations sufficiently risks exacerbating cattle TB, potentially making a bad situation worse. Farming leaders have managed to press forward with badger culling in the face of <a href="http://www.theguardian.com/theobserver/2012/oct/14/letters-observer">scientific consensus</a>, <a href="http://www.theguardian.com/environment/2014/oct/29/badger-cull-campaigners-lose-legal-battle">legal challenge</a>, <a href="https://yougov.co.uk/news/2014/09/11/two-years-badger-cull-remains-unpopular/">public opinion</a> and a groundswell of <a href="http://www.bbc.co.uk/news/science-environment-24223894">protest</a>. In future they may look back on such victories as Pyrrhic: one more such victory might undo the farmers they strive to support.</p><img src="https://counter.theconversation.com/content/36388/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rosie Woodroffe is grateful to receive research funding and in-kind support from Defra. Concerns raised here should not be interpreted as criticisms of any individual, nor of sterling efforts to control the TB problem.</span></em></p>
In the flurry of the holiday season, many people will have missed the government’s verdict on the 2014 badger culls, published on December 18. Farmers’ representatives have branded these recent culls “successful…
Rosie Woodroffe, Senior Research Fellow, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/32785
2014-10-16T05:27:00Z
2014-10-16T05:27:00Z
Ebola: bats get a bad rap when it comes to spreading diseases
<figure><img src="https://images.theconversation.com/files/61847/original/2dz2ss27-1413382353.jpg?ixlib=rb-1.1.0&rect=1%2C3%2C1022%2C599&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Just hanging.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/studioranslam/8550028895/sizes/l/in/photolist-e2x8Hi-e2x8Ug-bzvUQX-oeKfXn/">Diana Ranslam</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>In an era flush with vaccines and antibiotics, when the greatest health risks in the developed world ride on the back of fried fish and hamburgers, it is easy to forget that infectious diseases still account for a quarter of all human deaths worldwide. </p>
<p>Although this is a burden largely carried by more impoverished nations, the unfolding Ebola outbreak is a dramatic reminder that infectious diseases, and the dangers they pose, have no respect for country borders. </p>
<h2>Making the leap</h2>
<p>One of the greatest global health threats lies <a href="https://theconversation.com/why-are-emerging-viruses-here-and-why-now-29311">in emerging diseases</a>, which have never been seen before in humans or — as with Ebola — appear sporadically in new locations. Most emerging diseases are zoonoses, meaning they are caused by pathogens that can jump from animals into people. Out of more than 300 emerging infections identified since 1940, <a href="http://www.nature.com/nature/journal/v451/n7181/full/nature06536.html">over 60% are zoonotic</a>, and of these, 72% originate in wildlife. </p>
<p>Whereas some zoonotic infections, <a href="https://theconversation.com/rabies-a-global-killer-that-dog-jabs-can-eliminate-32289">such as rabies</a>, cannot be transmitted between human patients, others can spread across populations and borders: in 2003, SARS, a coronavirus linked to bats, <a href="https://theconversation.com/sars-mers-preparing-for-the-next-coronavirus-pandemic-16359">spread to several continents</a> within a few weeks before it was eliminated, while HIV has become, over several decades, a persistent pandemic. </p>
<p>The unpredictable nature and novelty of zoonotic pathogens make them incredibly difficult to defend against and respond to. But that does not mean we are helpless in the face of emerging ones. Because we know that the majority of zoonoses pass from wildlife, we can start to identify high-risk points for transmission by determining which wildlife species may pose the greatest risk. </p>
<h2>Searching for suspects</h2>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/61849/original/xshdc4vn-1413382683.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/61849/original/xshdc4vn-1413382683.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=721&fit=crop&dpr=1 600w, https://images.theconversation.com/files/61849/original/xshdc4vn-1413382683.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=721&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/61849/original/xshdc4vn-1413382683.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=721&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/61849/original/xshdc4vn-1413382683.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=906&fit=crop&dpr=1 754w, https://images.theconversation.com/files/61849/original/xshdc4vn-1413382683.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=906&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/61849/original/xshdc4vn-1413382683.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=906&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Testing for exposure to certain zoonotic pathogens.</span>
<span class="attribution"><span class="source">Alexandra Kamins</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Of all wildlife species, bats in particular pose complex questions. The second most diverse group of mammals after rodents, they host more than <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1539106/">65 known human pathogens</a>, including Ebola virus, coronavirus (the cause of SARS), henipaviruses (which can cause deadly encephalitis in humans) and rabies.</p>
<p>But they are also one of the mammalian groups most <a href="http://www.batcon.org/">vulnerable</a> to overhunting and habitat destruction, while providing indispensable ecological functions such as <a href="http://www.sciencemag.org/content/332/6025/41.short">pest control</a> by bats that eat insects, pollination and seed dispersal. </p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/61862/original/vpv88f6g-1413386960.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/61862/original/vpv88f6g-1413386960.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/61862/original/vpv88f6g-1413386960.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/61862/original/vpv88f6g-1413386960.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/61862/original/vpv88f6g-1413386960.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/61862/original/vpv88f6g-1413386960.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/61862/original/vpv88f6g-1413386960.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">Going bats for fruit.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/nano_maus/6592439229/sizes/l/in/photolist-b3xYvk-8eMjcb-69JhdP-8eMiWW-b3xY1i-b3xXEB-9XZimi-ceKDiJ-8wrpjz-734tpB-69Jhek-d2qBEq-d2qBPE-d2qBvE-d2qBV7-d2qC1o-6QP1AH-9YQmjG-bXodec-dzM5HZ-82E3qk-buogyC-e2x8Zc-e2x8Dg-e2x8Hi-e2x8Ug-bzvUQX-oeKfXn/">Nano maus</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/">CC BY-NC-SA</a></span>
</figcaption>
</figure>
<p>The loss of bats, whether from hunting or for disease control almost certainly would have far-reaching and long-lasting ecological and economic consequences.</p>
<p>This much we know, and yet the details of how zoonoses spill over from bats into people are vastly understudied. Understanding how humans and bats interact had, until recently, never been examined in West Africa, and only peripherally probed elsewhere in the world. Uncovering behaviour that brings humans into contact with bats and other wildlife, and exposes people to zoonoses, could provide invaluable clues for preventing zoonotic outbreaks. To address these questions, we put together an international network of collaborators, led in the UK by the <a href="http://www.zsl.org/science/research/people-wildlife-ecosystems">Zoological Society of London</a> and the <a href="http://www.vet.cam.ac.uk/ddu">University of Cambridge</a>. </p>
<p>From Malaysia to Ghana, from Australia to Peru, bats are coming into contact with humans more and more frequently as people are expanding into previously virgin territories. </p>
<h2>Bats as bushmeat</h2>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/61848/original/2kp4rs6n-1413382555.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/61848/original/2kp4rs6n-1413382555.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/61848/original/2kp4rs6n-1413382555.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/61848/original/2kp4rs6n-1413382555.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/61848/original/2kp4rs6n-1413382555.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/61848/original/2kp4rs6n-1413382555.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/61848/original/2kp4rs6n-1413382555.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">Smoked fruit bats for sale.</span>
<span class="attribution"><span class="source">Alexandra Kamins</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Fruit bats are also often attracted to orchards and gardens planted on the edge of their territories. But another human behaviour contributes significantly to the risk of zoonotic spillover from all wildlife species: hunting. The consumption of bushmeat, or wild animal meat, is a global phenomenon on a massive scale – estimates of the combined bushmeat consumption in Central Africa and the Amazon Basin exceed <a href="http://wwwnc.cdc.gov/eid/article/11/7/05-0194_article">1 billion kilograms annually</a>. </p>
<p>In Ghana, where fruit bats have tested positive for antibodies to <a href="http://dx.plos.org/10.1371/journal.pone.0002739.g001">henipaviruses</a> and <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3376795/">Ebola virus</a>, the status of bats as bushmeat was essentially unknown until we began our investigation five years ago. </p>
<p>In two recent studies carried out in Ghana, we reported how many people hunt bats for both food and money. We estimated that <a href="http://www.sciencedirect.com/science/article/pii/S000632071100348X">more than 100,000 fruit bats</a>, specifically the straw coloured fruit bat, are harvested every year. Bat meat likely provides an important secondary source of protein for the hunters and their families, especially when other sources such as fish or antelope are scarce. Bat meat also fetches a fairly high price at markets, supplementing a hunter’s often inconsistent income. </p>
<p>But hunters and those who prepare bat meat for sale or consumption also place themselves at risk of exposure to bat-borne zoonotic pathogens. Such pathogens can pass through blood, scratches, bites, and urine. Bat hunters handle live, often wounded bats and freshly killed bats, putting them into direct contact with bat blood and at risk of being bitten and scratched. Despite this, <a href="http://dx.doi.org/10.1007/s10393-014-0977-0">hunters are largely unaware of the risks they run</a>.</p>
<p>Understanding what risks bats pose, as little as we know, is only the beginning of the challenge. Reducing the risk of zoonoses is not simple or easy, and certainly not a simple question of stopping hunting or culling reservoir hosts. Whether eating their body weights in insects every night, or dispersing seeds from fruit trees across large areas, bats provide services to local economies worth billions of dollars across the world. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/61851/original/2s9bnq7x-1413382890.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/61851/original/2s9bnq7x-1413382890.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/61851/original/2s9bnq7x-1413382890.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/61851/original/2s9bnq7x-1413382890.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/61851/original/2s9bnq7x-1413382890.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/61851/original/2s9bnq7x-1413382890.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/61851/original/2s9bnq7x-1413382890.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">Hunter in Accra with a live, wounded bat he shot with a catapult.</span>
<span class="attribution"><span class="source">Alexandra Kamins</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Some people also depend on bat meat, and other bushmeat, <a href="http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0072807">for both their survival and livelihoods</a>. Bushmeat hunting often occurs in remote or impoverished places, where little infrastructure exists to support alternative livelihoods or even enforcement of hunting laws. Reducing risk sustainably and equitably will therefore likely need a combination of interventions, encompassing developmental approaches to strengthen local economies, expand job opportunities, and increase the supply of safer alternative protein sources in order to reduce the need to hunt wildlife – together with education to promote safer hunting practices. </p>
<p>Communities may have to change how they use land, and limit bushmeat hunting and human expansion activities to minimise the risks of spillover. At the same time, we need advances in medical technology and surveillance systems to monitor and swiftly respond when outbreaks do occur. </p>
<p>Such interventions can be complex and costly, but are essential. While the 2014 Ebola outbreak is the biggest to date, there will almost certainly be many zoonotic disease outbreaks in the future. By bringing together expertise from <a href="http://rstb.royalsocietypublishing.org/content/367/1604/2881.full.html">ecology, epidemiology and social sciences</a>, and concentrating on long-term management of risks, we hope to help communities maintain a safe and mutually beneficial relationship with their natural environment.</p><img src="https://counter.theconversation.com/content/32785/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alexandra Kamins was co-author of the paper 'Uncovering the fruit bat bushmeat commodity chain and the true extent of fruit bat hunting in Ghana, West Africa', funded by the University of Cambridge and the Gates Foundation. She works as a reacher for the Colorado Hospital Association.</span></em></p><p class="fine-print"><em><span>Marcus Rowcliffe was co-author of the paper 'Uncovering the fruit bat bushmeat commodity chain and the true extent of fruit bat hunting in Ghana, West Africa', funded by the University of Cambridge and the Gates Foundation. </span></em></p><p class="fine-print"><em><span>Olivier Restif is employed by the University of Cambridge, and receives funding from the Royal Society, the BBSRC and US Federal Agencies.</span></em></p>
In an era flush with vaccines and antibiotics, when the greatest health risks in the developed world ride on the back of fried fish and hamburgers, it is easy to forget that infectious diseases still account…
Alexandra Kamins, Research Analyst at the Colorado Hospital Association, Colorado Hospital Association
Marcus Rowcliffe, Research Fellow, Zoological Society of London
Olivier Restif, Royal Society University Research Fellow, University of Cambridge
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/31435
2014-09-09T05:32:48Z
2014-09-09T05:32:48Z
British government on the badger cull: ask scientists for help then ignore them
<figure><img src="https://images.theconversation.com/files/58456/original/v9xnkfsy-1410176626.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">All your fault.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/11561957@N06/10317142804">b/flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/">CC BY-NC-SA</a></span></figcaption></figure><p>Bovine tuberculosis (TB) is expected to cost British taxpayers nearly <a href="http://www.defra.gov.uk/animal-diseases/a-z/bovine-tb/about-bovine-tb/">£100m in 2014</a>. Scientific evidence is a vital weapon in the fight to protect cattle from TB. Why, then, has the government just fought and won a legal battle to avoid consulting independent scientists on its most high-profile TB control effort?</p>
<p>Wild badgers play a role in transmitting TB to cattle, and culling badgers seems an obvious solution. A new round of badger culls is about to start, but it is <a href="https://theconversation.com/uk/topics/badger-cull">risky</a> . A complex interaction between badger behaviour and TB transmission means that the results of culling could, depending on various factors, increase TB levels, instead of reducing them. To add to that, badger culling is expensive. </p>
<p>This is why, in 2013, the government started a pilot that it hoped would be give them a cheap and effective way to control cattle TB. Farmers, rather than government, would pay for the culling. And, rather than being cage-trapped, badgers would be shot in the wild. </p>
<p>This pilot was started in just two areas – and for good reason: the whole approach was untested, and the stakes were high. Marksmen shooting at night might endanger public safety. Shooting free-ranging badgers might cause suffering. And, worst of all for the aims of the approach, failing to kill enough badgers, fast enough, would worsen the cattle TB situation that the culls were intended to control.</p>
<p>In the face of <a href="http://www.theguardian.com/environment/2012/oct/13/badger-cull-mindless">such uncertainty</a>, the government adopted a commonly used approach. It <a href="https://www.gov.uk/government/publications/pilot-badger-culls-in-somerset-and-gloucestershire-report-by-the-independent-expert-panel">appointed</a> an Independent Expert Panel to assess the safety, humaneness and effectiveness of the pilot project. The expectation was that this panel’s conclusions would reflect scientific evidence, whether or not they supported government policy.</p>
<h2>Bring in the experts</h2>
<p>The Independent Expert Panel <a href="https://www.gov.uk/government/publications/pilot-badger-culls-in-somerset-and-gloucestershire-report-by-the-independent-expert-panel">found</a> that farmer-led culling was far from effective. Tasked with killing at least 70% of the local badgers within a six-week period, cull teams only managed to kill between 28% and 48%. Culling periods were extended, but still the total kill rose to only something between 31% and 56%, according to <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/300385/ahvla-extension-efficacy.pdf">government figures</a>. Unless more badgers could be killed, and faster, farmer-led culling risked worsening the problem it was intended to solve.</p>
<p>The 2013 culls also failed to meet their <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/300382/independent-expert-panel-report.pdf">targets for animal welfare</a>. Between 7.4% and 22.8% of badgers were still alive five minutes after being shot and were assumed to have experienced “marked pain”.</p>
<p>Despite facing these failures, the government decided to repeat culls in the same areas in 2014. If effectiveness and humaneness could be improved sufficiently, culling might be extended to more areas in 2015. If not, the government might need to reconsider their policy. One would think, then, that measuring effectiveness and humaneness would be a central goal of 2014’s culls.</p>
<h2>Then ignore their advice</h2>
<p>The Independent Expert Panel, together with government scientists, selected the most accurate and precise ways to estimate the effectiveness and humaneness of the 2013 culls. Measuring effectiveness is challenging because – being nocturnal and shy – badgers are hard to count. The panel overcame this problem by using genetic “fingerprints” to identify badgers from hair snagged on barbed wire. They measured humaneness primarily through independent observers recording the time that shot badgers took to die.</p>
<p>The panel recommended that the same approaches be used for subsequent culls. But the government rejected this <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/300424/pb14158-defra-response-independent-expert-panel.pdf">recommendation</a>. This year there will be no attempt to count badgers in the cull areas, either before or after the culls. The time badgers take to die will not be recorded. There will be no oversight by independent scientists.</p>
<p>Instead, the effectiveness of the culls which start tonight will be judged using a method so utterly inadequate it was barely considered in 2013. Key data will be collected by marksmen themselves: people with a vested interest in the cull being designated “effective” and “humane”, who in 2013 collected data so unreliable it was considered unusable by the panel. Available information suggests that any future claim that the 2014 culls have reduced badger numbers sufficiently to control TB will be completely baseless.</p>
<p>Why the change in approach? Government cites cost, and hired some expensive lawyers to defend its position when the Badger Trust sought, and eventually lost, a judicial review of the decision to scrap independent scientific oversight of this year’s culls. Yet the cost of pushing forward with an ineffective culling policy would far outweigh the cost of properly assessing effectiveness and humaneness.</p>
<p>Government has repeatedly referred to its programme of badger culling as “<a href="http://www.defra.gov.uk/animal-diseases/a-z/bovine-tb/badgers/culling/">science-led</a>”. One would expect a science-led policy to entail gathering reliable information on management outcomes, and using this and other evidence to inform future decisions. Choosing – against formal expert advice – to collect inconsistent, inadequate and potentially biased data is an insult to evidence-based policymaking. When ineffective culling can make a bad situation worse, failing to collect the evidence needed to evaluate future policy fails farmers, taxpayers and wildlife.</p>
<hr>
<p><em>Next, read this: <a href="https://theconversation.com/cattle-herd-model-reveals-best-ways-to-halt-spread-of-tb-and-a-badger-cull-isnt-one-of-them-28640">Cattle herd model reveals best ways to halt spread of TB – and a badger cull isn’t one of them</a></em></p><img src="https://counter.theconversation.com/content/31435/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rosie Woodroffe gratefully acknowledges research funding from Defra.</span></em></p>
Bovine tuberculosis (TB) is expected to cost British taxpayers nearly £100m in 2014. Scientific evidence is a vital weapon in the fight to protect cattle from TB. Why, then, has the government just fought…
Rosie Woodroffe, Senior Research Fellow, Zoological Society of London
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/25689
2014-04-21T05:20:02Z
2014-04-21T05:20:02Z
Satellites’ new ways of seeing nature can help protect it
<figure><img src="https://images.theconversation.com/files/46683/original/6gt2jqx5-1397734149.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Seeing beyond light: Landsat 8 OLI/TIRS false composite image of Lake Chad, West Africa.</span> <span class="attribution"><span class="source">Nathalie Pettorelli</span></span></figcaption></figure><p>The idea of using satellites to monitor wildlife and biological diversity probably conjures up images of radio-collared deer or tagged turtles. And while these have been key to increasing our understanding of animal distribution worldwide, we can track a lot more from space than you’d imagine – and it’s not necessary to capture and fit a tracking device first.</p>
<p>For example, <a href="http://www.grss-ieee.org/technical-resources-2/hyperspectral-sensors/">hyperspectral sensors</a> – which capture information across the electromagnetic spectrum in very narrow bands able to detect recognisable “fingerprints” of objects – <a href="http://rstb.royalsocietypublishing.org/content/369/1643/20130194">have been used</a> to determine genetic differences in <em>Populus tremuloides</em> (trembling aspen), one of the most widespread and genetically diverse species in North America. Satellite information on climatic conditions and on vegetation type and dynamics can help predict animal movement and condition. These are just two examples taken from a special edition I co-edited on <a href="http://rstb.royalsocietypublishing.org/site/2014/satellite.xhtml">satellites and conservation</a> in the Philosophical Transactions of the Royal Society B journal.</p>
<p>Who is interested in <a href="http://www.crisp.nus.edu.sg/%7Eresearch/tutorial/intro.htm">satellite remote sensing</a>? Basically anyone who seeks to understand large scale patterns in biodiversity distribution, or that has to deal with the management of big, remote, or inaccessible areas.</p>
<h2>An unparalleled view from above</h2>
<p>The level of information that can be derived from satellite data is pretty phenomenal, and too-often undervalued by ecologists and conservationists. For example, <a href="http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0033751">emperor penguin colonies</a> can be found and the colony size estimated using very high resolution images. Changes to the extent or density of ecosystems can be tracked, and active sensors such as radar and <a href="http://www.lidar-uk.com/">lidar</a> can report the 3D structure and density of vegetation. Just how “green” our world is can be extensively mapped on a fortnightly basis.</p>
<p>So satellites help monitor both wildlife and vegetation in the natural world, able to provide information about the most remote and inaccessible places on Earth. They also capture information that helps us understand why, and predict where, biodiversity is declining.</p>
<p>For example, measurements taken on the ground can be integrated with satellite data to track the current distributions of <a href="http://rstb.royalsocietypublishing.org/content/369/1643/20130192">certain invasive species</a>, and to predict their projected advance. High resolution images can be used to map problems associated with oil exploration and exploitation. The response of animals to shifts in temperatures or availability in food and resources can be <a href="http://rstb.royalsocietypublishing.org/content/369/1643/20130196">analysed and predicted</a> from satellite-based information. And deforestation, land degradation and the fragmentation of ecosystems as well as the expansion of urban areas have all been successfully monitored using satellites’ unique viewpoint.</p>
<p>Satellites’ benefits extend beyond land to the oceans too, as there are some great examples of how satellites can support marine conservation. Spotting and monitoring oil spills is a classic example, using radar or infrared sensors. And using satellite data together with that from vessels’ monitoring systems make it easier <a href="http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12261/abstract">to detect illegal, undeclared or unreported fishing</a>.</p>
<h2>Key new technologies need to be used</h2>
<p>Remote sensing is becoming central to our ability to understand and manage the natural world. From camera traps and microphone arrays, to guided drones and Doppler radar, ecologists, conservationists and environmental or wildlife managers have been drawn towards new technological developments that provide the possibility of non-invasive monitoring. </p>
<p>Satellite sensors are part of this incredibly powerful toolkit, and their scope to inform research and support resource management is continuously growing. For example, satellite data is now used to inform <a href="http://dopa.jrc.ec.europa.eu/">protected area management</a> or <a href="http://onlinelibrary.wiley.com/doi/10.1111/aje.12060/abstract">species reintroduction programs</a>.</p>
<p>Perhaps obviously, the best uses for this technology and major breakthroughs are most likely to occur when remote sensing and conservation experts collaborate; yet this happens all too rarely. Conservationists and wildlife managers need better links to technical expertise and access to equipment, and working together would be greatly enhanced by common information-sharing platforms and the development of a more coordinated research agenda. Google Earth is one thing, but making government-funded satellite data and the software tools to use it freely accessible would be a key step to increase the number of new purposes the research community can put it to.</p><img src="https://counter.theconversation.com/content/25689/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nathalie Pettorelli does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
The idea of using satellites to monitor wildlife and biological diversity probably conjures up images of radio-collared deer or tagged turtles. And while these have been key to increasing our understanding…
Nathalie Pettorelli, Research Fellow, Zoological Society of London
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