The world’s rarest horses have found an unlikely home in one of Earth’s most contaminated places – and they’re thriving.
According to Associated Press, across the Chernobyl exclusion zone in Ukraine, a stretch of abandoned land larger than Luxembourg, stocky sand-colored Przewalski’s horses graze among crumbling Soviet apartment blocks and forests that have swallowed entire roads. The scene would have been unthinkable four decades ago, when an explosion at the nuclear power plant on April 26, 1986, sent radiation pouring across Europe and forced tens of thousands of people from their homes in what became the worst nuclear disaster in history.
Humans haven’t lived here since. But animals – lots of them – have moved back in.
Wolves now roam the vast no-man’s-land that spans the Ukrainian and Belarusian border. Brown bears, absent from the area for more than a century, have returned. Populations of lynx, moose, red deer and even free-roaming packs of dogs have bounced back, and parts of the zone now look like European wilderness from hundreds of years ago.
“The fact that Ukraine now has a free-ranging population is something of a small miracle,” said Denys Vyshnevskyi, the zone’s lead nature scientist.
The Przewalski’s horses – known as “takhi” in their native Mongolia, meaning “spirit” – were introduced to the exclusion zone in 1998 as an experiment. The breed is genetically distinct from domestic horses, carrying 33 pairs of chromosomes compared with 32 in domesticated breeds, and was named after the Russian explorer who first formally identified the species. They had been declared extinct in the wild in 1969 and survived only through captive breeding programs.
Many of the horses died in those early years after their introduction to Chernobyl, but others adapted. Hidden cameras now capture them seeking shelter in crumbling barns and abandoned homes to escape harsh weather and insects – some even bed down inside the empty buildings. They live in small social groups, typically one stallion with several mares and their young, alongside separate bands of younger males.
Today, the global Przewalski’s horse population has climbed back to around 3,000, according to Florian Drouard, an operations manager at a reintroduction program at Cevennes National Park in southern France.
“This species is a remarkable example of successful reintroduction,” Drouard said. “While it is still far from being fully secure, it has shown that with proper preparation, a species kept in captivity can regain the social and ecological behaviors needed to live freely.”
The horse has also proved unexpectedly flexible, he noted – adapted to open steppe landscapes but now equally at home in Ukraine’s partly forested environment.
The transformation around them is visible everywhere. Trees burst through the roofs of abandoned apartment blocks in the ghost city of Pripyat. Roads have dissolved into forest. Weathered Soviet-era signs stand beside leaning wooden crosses in overgrown cemeteries.
Despite persistent radiation, scientists have not recorded widespread die-offs among the wildlife, though subtler effects have shown up. Some frogs have developed darker skin, and birds in higher-radiation areas are more likely to develop cataracts.
But new threats have emerged. Russia’s 2022 invasion of Ukraine brought fighting directly through the exclusion zone as troops advanced toward Kyiv, digging defenses into contaminated soil. Fires linked to military activity swept through the forests. Harsh wartime winters damaged the power grid in surrounding managed areas, and scientists report an increase in fallen trees and dead animals – casualties of extreme conditions and hastily built fortifications.
Forest fires remain a persistent danger. “Most forest fires are caused by downed drones,” said Oleksandr Polischuk, who leads a firefighting unit in the zone. “Sometimes we have to travel dozens of kilometers to reach them.” Those fires can send radioactive particles back into the air.
Today the zone is no longer just an accidental wildlife refuge. It has become a heavily monitored military corridor, marked by concrete barriers, barbed wire and minefields. Personnel rotate in and out to limit their radiation exposure, and the area is expected to remain off-limits for generations.
Vyshnevskyi, who often drives alone for hours through the zone setting motion-sensitive camera traps in camouflaged casings on trees, says he still marvels at what he sees.
“For those of us in conservation and ecology, it’s kind of a wonder,” he said. “This land was once heavily used – agriculture, cities, infrastructure. But nature has effectively performed a factory reset.”
