Mammals Thrive in Chernobyl Exclusion Zone

The Chernobyl disaster happened almost thirty years ago, a catastrophic event in the Ukraine that would become known as the worst nuclear accident in history. Around the site is an area known as the Exclusion Zone. It was initially set up soon after the accident as the designated distance for the evacuation of the more-than-100,000 people who lived there, but grew to cover 1,000 square miles (2,600km²). The purpose of the Zone, then and now, is to restrict access to contaminated areas, and make sure that contamination doesn't spread outside the Zone. It's still one of the most radioactively contaminated areas in the world, and yet some people still live there - illegally - despite the Ukrainian government trying to move them on. They've now been informally permitted to stay there, but the population has been steadily declining, and it's thought there are less than 200 people living in the area now. Now, it won't come as a surprise to you that in areas where there are fewer people, wildlife tends to thrive. And Professor Jim Smith of the University of Portsmouth has been leading a team who has been carrying out a long-term census of mammals in the area and found that wildlife has been returning. In fact, it's thought that the number of mammals is higher than they were before the disaster, and the team has published its findings in Current Biology. The team, with the help of colleagues from the Polesye State Radioecological Reserve in Belarus, used various means to estimate how many large and medium mammals were living in the area. They examined the data from aerial surveys and used footprints in the snow to calculate the number of different mammal species there were in the winter. These animal tracks were also tested to measure the levels of radioactive contamination. The first key fact the study revealed was that the abundance of animals was not negatively correlated with radioactivity levels, as was originally suspected. The second was that mammal numbers weren't any lower in the Exclusion Zone that at four different uncontaminated nature reserves in Belarus. The final piece of information the study yielded was that within a year of the disaster, animal populations began to stabilise and recover. In fact, wolf populations are seven times higher in the Zone than in the nearby nature reserves, and the numbers of deer, elk, and wild boar were at similar levels.

Professor Smith explained that although the report didn't look at the health effects of radiation on individual animals, it does reveal what happens in terms of wildlife conservation when you take humans out of the equation. He explained that even just innocently getting on with our everyday lives, humans cause more damage to the wildlife than the world's worst nuclear disaster. "Whatever negative effects there are from radiation, they are not as large as the negative effects of having people there," said the professor. Of course, Chernobyl was a disaster of catastrophic proportions and the study isn't trying to suggest otherwise. Professor Smith simply points out that the event provides a good illustration of just how the human population can affect the environment when compared to a nuclear accident. "Chernobyl caused a lot of human damage," he concluded. "If you can set that aside, it's hard to argue that it's really damaged the ecosystem as a whole."