text: In 1986, after a fire and explosion at the Chernobyl Nuclear Power Plant released radioactive particles into the air, thousands of people left the area, never to return. Now, researchers reporting in the Cell Press journal Current Biology on October 5 have found that the Chernobyl site looks less like a disaster zone and more like a nature preserve, teeming with elk, roe deer, red deer, wild boar, and wolves. 
   
   The findings are a reminder of the resilience of wildlife. They may also hold important lessons for understanding the potential long-term impact of the more recent Fukushima disaster in Japan. 
   
   "It's very likely that wildlife numbers at Chernobyl are much higher than they were before the accident," says Jim Smith of the University of Portsmouth in the UK. "This doesn't mean radiation is good for wildlife, just that the effects of human habitation, including hunting, farming, and forestry, are a lot worse." 
   
   Earlier studies in the 4,200 km2 Chernobyl Exclusion Zone showed major radiation effects and pronounced reductions in wildlife populations. The new evidence, based on long-term census data, now shows that mammal populations have bounced back. 
   
   The relative abundance of elk, roe deer, red deer, and wild boar within the exclusion zone are now similar to those in four uncontaminated nature reserves in the region, the researchers report. The number of wolves living in and around the Chernobyl site is more than seven times greater than can be found in those nature reserves. 
   
   Helicopter survey data also reveal rising trends in the abundance of elk, roe deer, and wild boar from 1 to 10 years after the accident. A dip in the wild boar population at one point was traced to a disease outbreak unrelated to radiation exposure. 
   
   "These results demonstrate for the first time that, regardless of potential radiation effects on individual animals, the Chernobyl Exclusion Zone supports an abundant mammal community after nearly three decades of chronic radiation exposure," the researchers conclude. They note that these increases came at a time when elk and wild boar populations were declining in other parts of the former Soviet Union. 
   
   "I've been working, studying, and taking photos of the wonderful wildlife in the Chernobyl area for over 20 years and am very pleased our work is reaching an international scientific audience," says Tatiana Deryabina from the Polessye State Radioecological Reserve in Belarus, a few miles from the site of the Chernobyl accident. 
   
   "These unique data showing a wide range of animals thriving within miles of a major nuclear accident illustrate the resilience of wildlife populations when freed from the pressures of human habitation," says Jim Beasley, a study co-author at the University of Georgia. ||||| People were evacuated after the Chernobyl accident, but what happened to the local wildlife? A new study shows that wildlife in the Chernobyl disaster zone is thriving, indicating that the presence of humans is more damaging to wildlife than is radiation poisoning 
   
   After a fire and explosion destroyed the Chernobyl Nuclear Power Plant in 1986, more than 100,000 people were permanently evacuated from the area to avoid radiation levels that were twenty times greater than the Hiroshima and Nagasaki bombings. But what happened to the local wildlife? According to a letter published today in the journal, Current Biology, scientists report that the Chernobyl disaster area is home to a rich and varied wildlife community, indicating that the mere presence of people is more damaging to wildlife than is radiation poisoning. 
   
   Chernobyl was a disaster for people, but for wildlife? Not so much 
   
   When the Chernobyl nuclear power plant melted down in 1986, more than 116,000 people were permanently relocated from a contaminated area comprising 4200 km2, an area that was later designated the Chernobyl exclusion zone. 
   
   Facebook Twitter Pinterest Chernobyl radiation map from the CIA’s online World Factbook. Chernobyl is indicated with a gold star. ( Sting [vectorisation], MTruch [English translation], Makeemlighter [English translation]). Illustration: CIA/Wikipedia. 
   
   But what happened to the local wildlife? Previous studies indicate that wildlife numbers initially dropped in the months after the accident (i.e.; doi:10.1098/rsbl.2008.0778). However, thirty years later, what effect is radiation contamination having on the abundance of Chernobyl’s large mammals? 
   
   An international team of researchers, headed by Tatiana Deryabina of the Polessye State Radioecological Reserve (PSRER), conducted surveys to find out. The PSRER is the Belarus sector of the Chernobyl exclusion zone. It covers 2,165 km2 (half of the total Chernobyl exclusion area) and has similar radiation levels to the Ukrainian sector. The findings for PSRER were compared to four nearby nature reserves that were uncontaminated by the Chernobyl accident: Berezinsky Biosphere Reserve, a state nature reserve covering 852 km2; Braslav Lakes National Park, which covers 645 km2; Belovezhskaya Puscha National Park, a UNESCO World Heritage site situated both in Poland (105 km2) and Belarus (1501 km2); and Narochansky National Park, which covers 874 km2. Of these, just two (Belovezhskaya Puscha and Narochansky National Park) allow limited wildlife hunting. 
   
   Facebook Twitter Pinterest Ermine (or stoat), Mustela erminea, in the Chernobyl exclusion zone. Photograph: Valeriy Yurko/T.G. Deryabina et al/Current Biology 2015 
   
   The team tested three fundamental hypotheses concerning the resilience of wildlife to the world’s worst nuclear accident: 
   
   Hypothesis 1: densities of mammals were suppressed due to the levels of radioactive contamination in the Chernobyl exclusion zone Hypothesis 2: densities of large mammals were suppressed at PSRER compared with those in four uncontaminated nature reserves in Belarus 
   
   Hypothesis 3: densities of large mammals declined between 1 and 10 years after the accident 
   
   To test these hypotheses, trained staff conducted wildlife snow track censuses between 2008 and 2010 along 35 permanent track survey routes (total combined length of 315 km with an average track length of 9 km) (doi:10.1016/j.ecolind.2012.10.025). Specific PSRER habitat types (former agricultural lands, former villages, evergreen forest, and deciduous forest) and levels of radiocæsium contamination density were mapped using GIS along each of these routes. 
   
   Aerial surveys were conducted between 1987 and 1997 from February through early March when snow cover was present. The study area survey took place from a height of 100 metres at a speed of 70-100 km/h and extended to approximately 250 metres on each side of the helicopter. 
   
   As you can see, the empirical data show no evidence of long-term radiation damage to the large mammal populations at Chernobyl, and thus, the evidence does not support any of the three hypotheses being tested (Figure 1): 
   
   Facebook Twitter Pinterest Figure 1. Animal abundances in the Chernobyl exclusion zone. (Top) Mean number of track counts per 10 km (in 2008–2010) for elk and wolf plotted against mean 137-Cs contamination density of each route. Analysis using linear mixed models including habitat variables found no evidence of correlation between mammal density and contamination density. (Bottom) Change in relative abundance of three species in the 10 years after the Chernobyl accident. Illustration: T.G. Deryabina et al (2015)/T.G. Deryabina et al/Current Biology 2015 
   
   In fact, increases in elk (moose) and wild boar populations in the Chernobyl exclusion zone occurred in the early 1990s, when these species’ populations were undergoing a rapid decline in former Soviet Union countries due to increased rural poverty and weakened wildlife management. 
   
   Further, the relative abundance of wolves living in and around the Chernobyl exclusion zone site is more than seven times greater than in the four nearby uncontaminated nature reserves. 
   
   Facebook Twitter Pinterest Wolves were seven times more abundant in the Chernobyl exclusion zone site than in nearby uncontaminated nature reserves. Photograph: Valeriy Yurko/T.G. Deryabina et al/Current Biology 2015 
   
   “There have long been rumours that the Chernobyl site has abundant wildlife — including carnivores — so I welcome this piece”, said wildlife demographer Tim Coulson, a Professor of Zoology at the University of Oxford, who was not part of this study. 
   
   “Because it is contaminated land, it is not easy to study wildlife in detail, and any studies are going to have to rely on approaches like this taken here”, said Professor Coulson in email. 
   
   In fact, this study demonstrates that, regardless of potential radiation effects on individual animals, the Chernobyl exclusion zone supports a thriving and abundant mammal community despite nearly three decades of chronic radiation exposure. 
   
   “It’s very likely that wildlife numbers at Chernobyl are much higher than they were before the accident,” said co-author Jim Smith, a Professor of Environmental Science at the University of Portsmouth, in a press release. 
   
   Facebook Twitter Pinterest Wild boar in the snow in the Chernobyl exclusion zone. Wild boar populations plummeted in 1993–1994 (Figure 1), due to a large increase in wolves as well as an outbreak of African swine fever. Photograph: Tatyana Deryabina/T.G. Deryabina et al/Current Biology 2015 
   
   Chernobyl’s wild boar populations grew especially fast -- until 1993-1994, when they suddenly crashed (Figure 1). This was due to a large increase in wolves, which are particularly fond of dining on wild boar, combined with an outbreak of African swine fever. 
   
   Humans are more damaging to wildlife and ecosystems than is radiation poisoning 
   
   “This study is a very positive move forward in conducting research concerning the potential health and environmental impacts of nuclear accidents”, said population biologist Timothy Mousseau, a Professor in the Biology Department at the University of South Carolina, who was not part of this study. 
   
   “I applaud the authors in their efforts to bring hard scientific data to bear on the question of impacts to wildlife in the stricken regions of Ukraine and Belarus. Much more research on this and related questions are desperately needed”, said Professor Mousseau in email. 
   
   “This doesn’t mean radiation is good for wildlife, just that the effects of human habitation, including hunting, farming, and forestry, are a lot worse,” said Professor Smith. 
   
   “This is an extremely sad indictment on how bad people are for wildlife”, agreed Professor Coulson. “Once [people] have left an area the wildlife appear to thrive — even if the habitat is laced with radiation.” 
   
   Although the detrimental effects of radiation on individual animals has been well documented, particularly on Chernobyl’s wildlife, its effects on populations isn’t so clear. 
   
   “This study does not address the issue of whether radiation has effects on reproduction, survival, longevity, or general health of the animals surveyed”, Professor Mousseau pointed out. 
   
   Nonetheless, this study indicates that populations of large mammals in the Chernobyl exclusion zone are doing at least as well as those in uncontaminated national parks in the vicinity. But sadly, this study clearly shows that putting a big fence around an area to keep people out is beneficial to wildlife, even if the negative effects of radiation contamination on wildlife -- increased mutation rates, cancers and other abnormalities -- may be masked by this advantage. 
   
   “Obviously I am not condoning nuclear accidents for the sake of wildlife! Far from it”, said Professor Coulson. “But hopefully some good can come from it. Hopefully we will realise that for wildlife and ecosystems to flourish, we must leave them be and stop interfering.” 
   
   In short, this paper suggests that not every nuclear wilderness is a bad thing. 
   
   Facebook Twitter Pinterest A group of wild boar frolic in front of abandoned buildings in the Chernobyl exclusion zone, free from human interference. Photograph: Valeriy Yurko/T.G. Deryabina et al/Current Biology 2015 
   
   Source: 
   
   T.G. Deryabina, S.V. Kuchmel, L.L. Nagorskaya, T.G. Hinton, J.C. Beasley, A. Lerebours, and J.T. Smith (2015). Long-term census data reveal abundant wildlife populations at Chernobyl, Current Biology, published online on 5 October 2015 ahead of print | doi:10.1016/j.cub.2015.08.017 (OA) 
   
   
   
   also cited: 
   
   Anders Pape Møller and Timothy A. Mousseau (2009). Reduced abundance of insects and spiders linked to radiation at Chernobyl 20 years after the accident, Biology Letters, 5:356–359 | doi:10.1098/rsbl.2008.0778 (OA) 
   
   Anders Pape Møller and Timothy A. Mousseau (2013). Assessing effects of radiation on abundance of mammals and predator–prey interactions in Chernobyl using tracks in the snow, Ecological Indicators, 26:112–116 | doi:10.1016/j.ecolind.2012.10.025 (free) 
   
   .. .. .. .. .. .. .. .. .. .. .. 
   
   
   
   GrrlScientist is very active on twitter @GrrlScientist ||||| Image copyright V Yurko Image caption The team carried out a long-term survey of mammals including wild boar 
   
   Removing humans from what is now the exclusion zone around the damaged Chernobyl nuclear reactor has allowed wildlife to return, researchers say. 
   
   They say a long-term census of mammals in the area has shown that wildlife numbers are likely to be "much higher than they were before the accident". 
   
   Professor Jim Smith of the University of Portsmouth led the study, published in the journal Current Biology. 
   
   He stressed that this "does not mean that radiation is good for wildlife". 
   
   "It's just that the effects of human habitation, including hunting, farming, and forestry, are a lot worse," Prof Smith said. 
   
   With the help of with colleagues from the Polesky State Radioecological Reserve in Belarus, the researchers examined data from aerial surveys that counted large mammals including roe deer, elk, wild boar and wolves. 
   
   Image copyright T Deryabina Image caption Tracks in the snow allowed the researchers to estimate roe deer populations in the exclusion zone 
   
   They also carried out tracking studies in the winter - using footprints in snow to calculate the numbers of different mammal species. And measuring the levels of radioactive contamination in those tracks. 
   
   "The numbers of animals we see in Chernobyl is similar to the populations in uncontaminated nature reserves," Prof Smith said. 
   
   The number of wolves was particularly striking - up to seven times higher than in nearby nature reserves of a comparable size. Prof Smith attributed this to the lack of hunting in the exclusion zone. 
   
   A 30km exclusion zone now surrounds the infamous Chernobyl nuclear power plant. And Prof Smith says the picture from this study reveals what happens in terms of wildlife conservation "when you take humans out of the picture". 
   
   Image copyright Valeriy Yurko Image caption Researchers think wolves in the exclusion zone have thrived thanks to a lack of hunting 
   
   But, he said, the study did not look at the health effects of radiation on individual animals. 
   
   That is something that Prof Tim Mousseau from the University of South Carolina, has spent many years trying to unpick in his studies of wildlife - particularly bird populations - in the exclusion zone. 
   
   Prof Mousseau said the study was a "very positive move forward in conducting research concerning the potential health and environmental impacts of nuclear accidents". 
   
   "Much more research on this is desperately needed," he added. 
   
   But Prof Mousseau is also troubled by "the characterisation that Chernobyl and the surrounding area is teeming with wildlife". 
   
   "This study only applies to large mammals under hunting pressure, rather than the vast majority of animals - most birds, small mammals, and insects - that are not directly influenced by human habitation," he told BBC News. 
   
   Image copyright Victoria Gill/BBC Image caption In Pripyat, the largest town in the exclusion zone, it is difficult to tell where the town ends and the wilderness begins 
   
   In their study of mammal tracks, however, Prof Smith and his colleagues did compare the abundance of animals in different areas of the exclusion zone. They found that more contaminated areas had just as many animals as less contaminated sites. 
   
   Prof Mousseau said that the study simply showed that, "if left unchecked, some populations of animals will grow exponentially and eventually overpopulate a region". 
   
   "There is no evidence that the animals of Chernobyl are achieving the levels of population growth that are frequently seen in other regions where they are protected from predation or hunting," he added.
target: – What happens when humans abandon 1,600 square miles because of radioactivity? Wildlife runs rampant, apparently. A new study on animals in the Chernobyl Exclusion Zone shows what once looked something like a wasteland is now packed with elk, roe deer, red deer, wild boar, and wolves. Researchers conducted aerial surveys in the zone during winter months between 1987—a year after the Chernobyl disaster—and 1997 and estimated animal populations based on tracks in the snow, reports the Guardian. They found the number of animals in the area was actually on par with those in four uncontaminated nature reserves nearby; but the number of wolves was more than seven times greater than in reserves. The numbers of elk, roe deer, and wild boar also jumped at a time when elk and wild boar populations were sliding elsewhere in the former Soviet Union. "It's very likely that wildlife numbers at Chernobyl are much higher than they were before the accident," a researcher says in a release. "This doesn't mean radiation is good for wildlife, just that the effects of human habitation, including hunting, farming, and forestry, are a lot worse." But another researcher who has studied birds in the zone tells the BBC the research "only applies to large mammals under hunting pressure, rather than the vast majority of animals—most birds, small mammals, and insects—that are not directly influenced by human habitation." And since the study didn't look at radiation exposure, it "does not address the issue of whether radiation has effects on reproduction, survival, longevity, or general health of the animals surveyed." While scientists found Chernobyl's wild boar population dipped in 1993, they say hungry wolves and a disease outbreak were to blame. (There's something wrong with Chernobyl's forests.)