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20,000 years ago, stone-age humans engraved depictions of wild horses onto cave walls. Over the millennia that followed, the horses were driven to the brink of extinction by hunting, interbreeding, and environmental change.

Today, only one species of wild horse remains. Known as the Przewalski’s horse, the short, stocky, zebra-like animal once roamed throughout Europe and Asia.

But by the 20th century, the horses, named after Nikolai Przewalski, a Russian explorer who brought a skull of the horse to Russia from Central Asia in 1878, were facing extinction. According to Prague Zoo, which is heavily involved in conservation efforts, the species reached its lowest point in 1945, with only 31 remaining in captivity. In 1969, a Mongolian scientist made what some thought would be the last ever sighting of a Przewalski’s horse in the wild.

However, over the past 40 years, the breeding of captive populations and reintroductions in Europe and Asia have brought the Przewalski’s horse back from the brink. Conservation efforts – the latest of which returned the horses to Kazakhstan in June this year – have involved international collaboration, transfer by military aircraft, and even letting them loose in the Chernobyl exclusion zone. Now, according to Prague Zoo, there are about 3,000 living today, with approximately 1,000 regulated in the wild and around 180 fully wild.

In contrast to the feral descendants of domesticated horses that now roam free in Australia and North America, <a href="index.php?page=&url=https%3A%2F%2Fnationalzoo.si.edu%2Fanimals%2Fprzewalskis-horse%23%3A%7E%3Atext%3DPrzewalski%26apos%3Bs%2520horses%252C%2520critically%2520endangered%2520horses%2Ccommon%2520ancestor%2520500%252C000%2520years%2520ago" target="_blank">scientists believe</a> that Przewalski’s horses have never been domesticated and are therefore unique in being truly wild. “It is very hard to explain the difference between a domesticated and a wild horse,” says Filip Mašek, spokesperson for Prague Zoo, which received its <a href="index.php?page=&url=https%3A%2F%2Fwww.zoopraha.cz%2Fen%2Fabout-zoo%2Fhistory" target="_blank">first pair of horses in 1931</a>, “this is a wild animal that you have to be very careful around.” Here, a Przewalski’s horse stands inside a breeding enclosure in Prague on April 22, 2021.
In contrast to the feral descendants of domesticated horses that now roam free in Australia and North America, scientists believe that Przewalski’s horses have never been domesticated and are therefore unique in being truly wild. “It is very hard to explain the difference between a domesticated and a wild horse,” says Filip Mašek, spokesperson for Prague Zoo, which received its first pair of horses in 1931, “this is a wild animal that you have to be very careful around.” Here, a Przewalski’s horse stands inside a breeding enclosure in Prague on April 22, 2021.
David W. Cerny/Reuters
Przewalski’s horses are short and heavily built, typically <a href="index.php?page=&url=https%3A%2F%2Fnationalzoo.si.edu%2Fanimals%2Fprzewalskis-horse" target="_blank">around five feet (1.5 meters)</a> tall and weighing<strong> </strong><a href="index.php?page=&url=https%3A%2F%2Fnationalzoo.si.edu%2Fanimals%2Fprzewalskis-horse" target="_blank">between 550 and 800 pounds</a> (250 to 360 kilograms). Their aggressive demeanour and erect mane have drawn comparisons with zebras. They typically live on the steppes of Europe and Asia – vast, flat areas of unforested grassland where temperatures<strong> </strong>can be <a href="index.php?page=&url=https%3A%2F%2Fnationalzoo.si.edu%2Fanimals%2Fprzewalskis-horse%23%3A%7E%3Atext%3DPrzewalski%26apos%3Bs%2520horses%2520once%2520ranged%2520throughout%2CMongolia%252C%2520China%252C%2520and%2520Kazakhstan." target="_blank">extreme</a>, reaching as high as 104 degrees Fahrenheit (40 degrees Celsius) in summer and minus 50 degrees Fahrenheit (minus 45 degrees Celsius) in winter. Their coats, those of this herd seen in the snow of Prague Zoo's breeding center in Dolní Dobřejov, Czech Republic, thicken in winter and shed, along with their manes, in spring. They live in family groups with a single stallion and several mares, explains Ganbaatar Oyunsaikhan, who has worked with Przewalski’s horses in Mongolia for 25 years, and group decisions are generally made democratically. At around two years old, young males are driven away by the stallion to find a new group. “They are truly beautiful creatures,” he says.
Przewalski’s horses are short and heavily built, typically around five feet (1.5 meters) tall and weighing between 550 and 800 pounds (250 to 360 kilograms). Their aggressive demeanour and erect mane have drawn comparisons with zebras. They typically live on the steppes of Europe and Asia – vast, flat areas of unforested grassland where temperatures can be extreme, reaching as high as 104 degrees Fahrenheit (40 degrees Celsius) in summer and minus 50 degrees Fahrenheit (minus 45 degrees Celsius) in winter. Their coats, those of this herd seen in the snow of Prague Zoo's breeding center in Dolní Dobřejov, Czech Republic, thicken in winter and shed, along with their manes, in spring. They live in family groups with a single stallion and several mares, explains Ganbaatar Oyunsaikhan, who has worked with Przewalski’s horses in Mongolia for 25 years, and group decisions are generally made democratically. At around two years old, young males are driven away by the stallion to find a new group. “They are truly beautiful creatures,” he says.
Miroslav Bobek/Prague Zoo
In the early 20th century, the population of Przewalski’s horses <a href="index.php?page=&url=https%3A%2F%2Fpmc.ncbi.nlm.nih.gov%2Farticles%2FPMC6769756%2F" target="_blank">collapsed</a>. According to Prague Zoo, by 1945 there were just two prosperous breeding groups, in Prague and Munich. In 1959, the zoo established the international studbook for the species – a record of the locations and sex of all known Przewalski’s horses in the world – in an attempt to grow its population through collaboration. This image shows a Przewalski's horse in a designated wilderness zone near Dallgow-D'beritz, Brandenburg, Germany, on November 16, 2020.
In the early 20th century, the population of Przewalski’s horses collapsed. According to Prague Zoo, by 1945 there were just two prosperous breeding groups, in Prague and Munich. In 1959, the zoo established the international studbook for the species – a record of the locations and sex of all known Przewalski’s horses in the world – in an attempt to grow its population through collaboration. This image shows a Przewalski's horse in a designated wilderness zone near Dallgow-D'beritz, Brandenburg, Germany, on November 16, 2020.
Ingolf K'nig-Jablonski/picture-alliance/dpa/AP
The studbook, the <a href="index.php?page=&url=https%3A%2F%2Fwww.waza.org%2Fpriorities%2Fconservation%2Fwaza-international-studbooks%2F" target="_blank">oldest conservation studbook still running today</a> under the auspices of the World Association of Zoos and Aquariums, was an international success. Between 1985 and 2005, 24 captive Przewalski’s horses <a href="index.php?page=&url=https%3A%2F%2Fncr-journal.bear-land.org%2Fuploads%2Fa5a6240a82d7eedfd55d824a44e9baff.pdf" target="_blank">were transported</a> from the UK, the US and Germany to the Jimsar Wild Horse Breeding Center in Xinjiang, China. By 2018, there were <a href="index.php?page=&url=https%3A%2F%2Fncr-journal.bear-land.org%2Fuploads%2Fa5a6240a82d7eedfd55d824a44e9baff.pdf" target="_blank">413 wild horse descendants</a> in the region. In the 1990s, similar reintroduction efforts took place in Mongolia, where, according to Prague Zoo, there are now 800 horses, including this pair photographed in the the Great Gobi B Strictly Protected Area on June 23, 2017. Transporting a wild horse from Europe or the US to Asia is difficult, Mašek explains; journeys take tens of hours on planes and in cars and require the exact right quantity of sedatives for the horses – just enough to prevent them from lashing out, but not too much that they sit down while traveling and cut off blood circulation, which can render them unable to stand up again.
The studbook, the oldest conservation studbook still running today under the auspices of the World Association of Zoos and Aquariums, was an international success. Between 1985 and 2005, 24 captive Przewalski’s horses were transported from the UK, the US and Germany to the Jimsar Wild Horse Breeding Center in Xinjiang, China. By 2018, there were 413 wild horse descendants in the region. In the 1990s, similar reintroduction efforts took place in Mongolia, where, according to Prague Zoo, there are now 800 horses, including this pair photographed in the the Great Gobi B Strictly Protected Area on June 23, 2017. Transporting a wild horse from Europe or the US to Asia is difficult, Mašek explains; journeys take tens of hours on planes and in cars and require the exact right quantity of sedatives for the horses – just enough to prevent them from lashing out, but not too much that they sit down while traveling and cut off blood circulation, which can render them unable to stand up again.
David W. Cerny/Reuters
Ukraine’s Chernobyl exclusion zone – an area of 1,000 square miles (2,600 square kilometers) around the site of the nuclear disaster – has become a haven for wildlife since it became unsuitable for human habitation in 1986. 12 years later, around 30 Przewalski’s horses were released into the zone. Like other animals in the undisturbed ecosystem, the horses have flourished, now numbering <a href="index.php?page=&url=https%3A%2F%2Fphys.org%2Fnews%2F2021-04-wild-horses-flourish-chernobyl-years.html%23%3A%7E%3Atext%3DIt%2520was%2520reintroduced%2520by%2520scientists%2Cover%2520the%2520border%2520in%2520Belarus.%26text%3D%2522Paradoxically%252C%2520this%2520is%2520a%2520unique%2Cthe%2520region%252C%2522%2520he%2520said." target="_blank">approximately 150</a>, including this one seen on April 12, 2021.
Ukraine’s Chernobyl exclusion zone – an area of 1,000 square miles (2,600 square kilometers) around the site of the nuclear disaster – has become a haven for wildlife since it became unsuitable for human habitation in 1986. 12 years later, around 30 Przewalski’s horses were released into the zone. Like other animals in the undisturbed ecosystem, the horses have flourished, now numbering approximately 150, including this one seen on April 12, 2021.
Gleb Garanich/Reuters
The most recent success story is in Kazakhstan, where seven Przewalski’s horses were transported from Prague and Berlin zoos <a href="index.php?page=&url=https%3A%2F%2Fwww.zoopraha.cz%2Fen%2Fabout-zoo%2Fnews%2F14768-prague-zoo-transported-first-przewalski-s-horses-to-the-steppes-of-kazakhstan%23%3A%7E%3Atext%3DFirst%2520three%2520Przewalski%26apos%3Bs%2520horses%2520were%2Cin%2520Arkalyk%2520in%2520Central%2520Kazakhstan" target="_blank">in June this year</a>, including this horse, on its way to the Alibi field station and reintroduction center on June 4, 2024. They were flown in Czech military aircrafts to Kazakhstan and transported to the<strong> </strong>“Golden Steppe,” where they have begun adapting to the wild. “To see the first horses actually run out of the box, people were crying,” recalls Mašek, who was present in Kazakhstan for the reintroduction. “It was amazing, a once in a lifetime experience.” The big test will come in winter, he adds, when the horses will have to dig beneath the snow for food.
The most recent success story is in Kazakhstan, where seven Przewalski’s horses were transported from Prague and Berlin zoos in June this year, including this horse, on its way to the Alibi field station and reintroduction center on June 4, 2024. They were flown in Czech military aircrafts to Kazakhstan and transported to the “Golden Steppe,” where they have begun adapting to the wild. “To see the first horses actually run out of the box, people were crying,” recalls Mašek, who was present in Kazakhstan for the reintroduction. “It was amazing, a once in a lifetime experience.” The big test will come in winter, he adds, when the horses will have to dig beneath the snow for food.
David W. Cerny/Reuters
Returning the horses to Kazakhstan, including this one released into an acclimatization enclosure on June 4, 2024, was not all plain sailing, says Mašek. Zoo representatives have dealt with floods destroying the reintroduction center (an eight-hour journey from the nearest airport), a military plane breaking down, and the challenge of communicating the importance of preserving the horses in the wild. But, in the end, “it just clicked,” he says. “When the horses were running away from us into the steppe, the second and third one, they did this circle and looked at us, and it almost looked like they said, ‘thank you.’”
Returning the horses to Kazakhstan, including this one released into an acclimatization enclosure on June 4, 2024, was not all plain sailing, says Mašek. Zoo representatives have dealt with floods destroying the reintroduction center (an eight-hour journey from the nearest airport), a military plane breaking down, and the challenge of communicating the importance of preserving the horses in the wild. But, in the end, “it just clicked,” he says. “When the horses were running away from us into the steppe, the second and third one, they did this circle and looked at us, and it almost looked like they said, ‘thank you.’”
David W. Cerny/Reuters