11 Surprising Facts About Chernobyl's Wildlife

Nearly four decades after the catastrophic 1986 Chernobyl disaster, life is making a comeback in the exclusion zone. Wild animals are thriving in the contaminated area, with adorable puppies becoming a sensation online. Tourists, inspired by the acclaimed HBO series Chernobyl, are snapping selfies in front of the eerie ruins. Once deemed permanently uninhabitable, the Chernobyl Exclusion Zone has turned into a sanctuary for wildlife, demonstrating that, as the famous line from Jurassic Park goes, life always finds a way.

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1. Against all odds, animals in Chernobyl have not only survived but thrived.

A flawed reactor design and inadequately trained personnel were key factors leading to the catastrophic explosion at Reactor 4 of the Chernobyl nuclear plant on April 26, 1986. The disaster caused widespread environmental devastation, releasing radioactive material at levels hundreds of times greater than those from the Hiroshima atomic bomb.

The radiation from the Chernobyl disaster caused the leaves of thousands of trees near the plant and the nearby Ukrainian city of Pripyat to turn a distinct rust color, which gave rise to the name Red Forest. Eventually, workers bulldozed and buried the radioactive trees. Soviet conscripts were also ordered to shoot any stray animals within the 1,000-square-mile Chernobyl Exclusion Zone. Although experts believe some areas will remain unsafe for human habitation for up to 20,000 years, many animal and plant species have not only survived but flourished.

2. The absence of human activity is allowing Chernobyl to revert back to wilderness.

As WIRED highlights, the Chernobyl disaster has inadvertently become an experiment in what the Earth would look like without humans. Hunting is prohibited, and living within the Chernobyl Exclusion Zone is not recommended. With fewer humans, nature has been able to reclaim its territory without the pressures of human activity. According to The Guardian, a new nature reserve in the Belarusian section of the zone has dubbed itself “Europe’s largest experiment in rewilding,” with animals growing less fearful of humans. In fact, some species are thriving more within the Exclusion Zone than they are outside it.

3. Bears and wolves now outnumber humans in the Chernobyl disaster zone.

Biologist Jim Beasley reports that the population of large mammals in the Chernobyl Exclusion Zone has exceeded pre-disaster numbers. Species like bears, wolves, lynx, bison, deer, moose, beavers, foxes, badgers, wild boar, and raccoon dogs have found a comfortable home in the radioactive environment. In addition to these larger creatures, a wide range of amphibians, fish, worms, and bacteria thrive in the now human-free zone.

While continuous low-level radiation may not be beneficial, it seems that for some animals, the harm it causes is outweighed by the benefits of escaping the prior destructive impact of human activities such as habitat encroachment and hunting.

Wolves, in particular, may actually gain from their ability to travel vast distances, which helps dilute the radiation they consume while hunting. Beasley found the wolf population density in Chernobyl to be much higher than in America’s Yellowstone National Park. As he told National Geographic, 'The removal of humans from the system far outweighs any potential radiation effects.'

4. Chernobyl is helping an endangered wild horse species make a comeback.

The Smithsonian’s National Zoo & Conservation Biology Institute has called Przewalski’s horses 'the last truly wild horse.' While other species commonly referred to as wild, such as those on the United States’ Assateague Island National Seashore, are actually feral domestic horses—descended from animals that escaped domestication—whether Przewalski horses, also known as Takhi, can be considered a true wild species or subspecies is a topic of debate. What is certain, however, is that this once widespread species, which roamed much of Asia and Europe, was nearly wiped out. In the 1994 edited book by Lee Boyd and Katherine A. Houpt, the last confirmed sighting in the wild was recorded in the late 1960s, leading the authors to declare them 'extinct in the wild.'

However, British ecologists Mike Wood and Nick Beresford, experts on the impact of radiation on Chernobyl’s wildlife, discovered that Przewalski’s horses are thriving in the Chernobyl Exclusion Zone. In the late 1990s, around 30 Przewalski’s horses were introduced to the Ukrainian side of the zone, and the population has now grown to more than 200. Camera trap footage has shown that some of the original horses (identified by their brand markings) are still alive, and pictures of foals and young horses suggest that the population is expanding.

5. Radiation may have wiped out Chernobyl’s insect population.

Unlike large predators and other large animals, insects and spiders around Chernobyl have seen a sharp decline in numbers. A 2009 study published in Biology Letters showed that areas with higher radiation levels had significantly fewer invertebrates. A similar pattern was observed following the 2011 nuclear disaster at Fukushima, where populations of birds, cicadas, and butterflies dropped, though other species remained largely unaffected.

6. Chernobyl's animals are experiencing mutations...

Scientists have observed significant genetic alterations in species affected by the Chernobyl disaster: A 2011 study in Biological Conservation found that genetic mutations in plants and animals had increased twentyfold due to radiation. Rare bird species in the area were particularly affected by the explosion's radiation, suffering more than common species. Ongoing research is required to understand how these mutations impact species' reproductive success, population size, genetic diversity, and other factors critical to their survival.

In 2018, scientist Michael Byrne tracked a wolf that traveled far beyond the Exclusion Zone and pondered whether the high mutation rate in Chernobyl's animals could spread to other populations. While acknowledging his uncertainty, Byrne stated, 'I don’t want to say that animals from Chernobyl are contaminating the world. But if there are any mutations that could be passed on, it’s something worth considering.'

7. ... but the results might not be what you expect.

This doesn’t mean the Exclusion Zone is filled with three-eyed fish or two-headed cows, though. In 2016, videos surfaced showing some exceptionally large catfish in the Chernobyl reactor’s cooling pond, which led some to believe radiation had boosted their growth. However, mutations caused by radiation typically don’t result in larger animals. Such mutations usually impair an animal’s fitness and ability to reach full size, let alone become some sort of oversized creature. The explanation for the large catfish is actually simpler: some fish just grow really big.

Oddities have certainly been observed in the area, and tour guides advise visitors not to pet Chernobyl animals due to potential radioactive particles in their fur. But today’s wild animals are still sporting the usual number of limbs and are not glowing. It seems that the most notable genetic mutations occurred right after the explosion at Reactor Four, which is consistent with the effects seen in humans. About 30 people died within months due to acute radiation sickness. Long-term deaths related to the disaster remain debated, though studies show higher rates of thyroid cancer in individuals (especially children) exposed to Chernobyl’s radiation, likely through contaminated food. Surprisingly, a study published in Science found that parents who experienced genetic mutations from radiation exposure did not pass those mutations on to their children.

It makes sense that the most significant effects would have been felt immediately after the disaster, considering how radiation behaves. Over the years, some of the dangerous radionuclides released by the explosion have decayed, making the area likely safer for habitation. For example, uncontrolled iodine-131 exposure is known to increase the risk of thyroid diseases, including cancer, but it has a half-life of only eight days, meaning it would have largely vanished from the zone within a few months.

8. Voles show several concerning trends …

Other radioactive isotopes remain in considerable amounts. Cesium-137, for instance, has a half-life of over 30 years. Certain animals are disproportionately affected, with diet being a key factor. Voles, small and adorable rodents, have a tendency to eat a lot of mushrooms, and unfortunately, some species of mushrooms excel at accumulating radiation, which then passes to the voles. This exposure seems to lead to harmful effects: Studies have shown voles in areas with higher radiation levels were less fertile, contributing to population declines. They also exhibited higher rates of cataracts compared to animals from outside the Exclusion Zone.

9. ... As do birds.

Barn swallows in the area have shown elevated levels of partial albinism, likely due to radiation-induced genetic mutations. In areas with higher radiation, bird populations seem to experience smaller brain sizes, less viable sperm, and decreased species diversity and abundance. So, while the story of Chernobyl’s wildlife isn’t simply one of the land returning to a thriving paradise, it also isn’t as bleak as one might expect from a barren wasteland.

10. Some dogs from Chernobyl found new homes.

Hundreds of dogs—the descendants of pets left behind by their owners during the evacuation on April 27, 1986—have made the Chernobyl Exclusion Zone their home. Today, the Clean Future Fund is dedicated to sterilizing these dogs and providing them with medical treatment, vaccines, and even food. This organization also helps the area’s cats.

In 2018 and 2019, a number of dogs were found to have safe radiation levels, and several dozen were adopted. However, by mid-2022, the ongoing pandemic and the Russian invasion of Ukraine disrupted these efforts, though some work continues sporadically within the Exclusion Zone.

11. Some humans still live in the Exclusion Zone.

Some of the dogs from Chernobyl have been adopted by residents of the Exclusion Zone. Despite laws that prohibit settlement, several humans continue to live in the area, often with unspoken approval from authorities. These inhabitants, known as Samosely or self-settlers, are predominantly elderly women, many of whom resided in the area before the disaster. They believe that the benefits of staying—be it financial, cultural, or personal—outweigh the risks of radiation exposure.

This article is adapted from a post originally published in 2019 and an episode of The List Show on YouTube, updated for 2023.