Wildlife thrive in Chernobyl's nuclear winter

Still inhospitable to humans, the Chernobyl "exclusion zone", a contaminated 18.6-mile radius around the site of the nuclear reactor explosion of April 26, 1986, is now a nature reserve and teems with wolves, moose, bison, wild boars and bears.

Boars, which generally confine their sorties to dusk, plunder what remains of gardens in the daytime, strolling down empty village streets, wandering into farms and settlements in search of food.

Moose also venture out – like the cow and her two young which appear on the roadside to munch on low-hanging branches.

"Moose are very curious creatures," says Grigory Sys, one of the naturalists who oversee the animals in the still-radioactive forest. "They'll want to have a good look at us for a couple of minutes before heading off into the forest."

Since I met him about four years ago, I've accompanied Sys a half-dozen times round the 1,090-square-mile zone, emptied of people by the fire and explosion at the plant just over the border in Ukraine.

Belarus, downwind from the blast, was the country worst affected by the world's worst civil nuclear accident. A quarter of its territory was contaminated and villages deserted on both sides of the border between what were then Soviet republics.

The human hardship was immense. Dozens died putting out the blaze, there were mass evacuations of tens of thousands of people – sometimes twice as the authorities underestimated the extent of radiation – thousands developed thyroid cancer.

But it was undeniably a good thing for wildlife.

"You'll see – they run off a bit, but will then stop," Sys says of the moose.

Touring the zone with Sys means spending several nights in a forest shack, with three simple beds and a stove.

We take my car through the zone's abandoned villages. Houses, personal possessions, shops, even amenities like amusement parks, are left untouched from late in the Soviet era.

Sys says the wolves, now numbering 300, are in charge.

"The wolf is very clever and cunning. He earns the respect of any adversary," he says. "They used to be killed off at any opportunity in the hundreds, even from helicopters. But they adapted and survived."

Killing wolves is now prohibited, with only a handful culled each year for scientific research. That has let them dominate the abandoned forests and meadows, although some farmers outside the zone say wolves raid their livestock. Residents of two villages saw wolves in the streets and one woman was killed in a confrontation with them.

Wolf tracks are everywhere. Guides hear them howling in the night.

During a break for a snack in one village, Sys suddenly stops and hisses at me not to move.

The grey animal is now visible on the road about 200 metres away, trying to assess what we are doing there with our car. In an instant it darts to the left and disappears into the forest.

Now free from the influence of human habitation, wolves have altered their feeding habits and their main prey has become the packs of boars. The free-roaming boars now push their way into what is supposed to be a feeding station for the reserve's bison herd.

"We feed the bison here in the winter. The boars often come here in the evening to try to get their share of the feed," Sys said. "It's quite fun to see how the bison chase them away."

Guides report plenty of bear tracks in the area as well as lynx, animals classed as an endangered species in Belarus.

Some wildlife have disappeared because of the changes.

The white stork, once a familiar figure in the area's towns, disliked the isolation and headed off in search of populated areas. But the black stork, fond of thick forests, stayed.

One newcomer is the white-tailed eagle, the largest eagle in Belarus, rarely spotted in proximity to man. Sys says he has seen five nests in an area now clearly suited to the birds.

Some birds even choose to spend winter here, catching their fill of fish at unfrozen lakes inside the zone.

The reserve – and the freedom afforded to animals by the absence of human habitation – remains a huge magnet to researchers. But tourists and the curious are not welcome.

"We are happy to welcome here fellow scientists from other countries to work on joint projects," said its director, Pytor Kudan. "But we don't want tourists or amateur bird or animal-lovers. We have very specific conditions here. And one of them remains high radiation, sometimes very high radiation."