Our research shows that the number of large mammals at Chernobyl is similar to that in uncontaminated nature reserves in Belarus - except for wolves, which are far more numerous in the area around the reactor. The area is also home to lynx and even a few brown bears. Nor do the population data show any link between radiation levels and mammal densities; the number of mammals in the most contaminated parts of the zone is similar to that in the least contaminated parts.

To be sure, the fact that animals are thriving at Chernobyl does not mean that radiation is good for wildlife. Radiation does cause DNA damage, and at current levels we cannot rule out some effects on the reproduction of individual animals.

But a comparison with what happened outside the affected area is instructive. Compared with the damage radiation has wrought, human habitation has caused far greater destruction. Indeed, in areas outside the zone or nature reserves, populations of elk and wild boar underwent steep declines, as major socioeconomic changes after the fall of the Soviet Union worsened rural poverty and crippled wildlife management.

The lesson from Chernobyl is that if nature is to thrive, it must be given space - from us. The primary causes behind declining global biodiversity include habitat loss and fragmentation as a result of human activity.

Even some of our most well-meaning environmental efforts, such as the fight against climate change, have led to the expansion of the human presence into previously untouched wilderness. Demand for biofuels, for example, has been linked to deforestation. There are no easy solutions, of course, and all efforts to address the problem will be complicated by continuing rapid growth of the world's human population. But one thing is clear: we, as a species, need to think more carefully about our impact on the nonhuman animal population and begin to take better account of these effects in our economic and environmental policies.

The author is Professor at the School of Earth and Environmental Science at the University of Portsmouth.

Project Syndicate