By Anthony Ham
When Russian scientists released a pair of orphaned Amur tiger cubs into the wild in a remote corner of Russia’s far-east in 2014, they were trying to save a species. While the tigers, sometimes called Siberian tigers and the world’s largest big cats, remain endangered, the scientists created something else: an unlikely love story.
The cubs, Boris and Svetlaya, had been rescued from the wild as unrelated three- to five-month-old cubs in the Sikhote-Alin mountains, the animals’ main stronghold. They grew up in captivity and were released at 18 months old. The cats were separated by more than 160 kilometres with the goal of expanding the distribution of released tigers as much as possible in the Pri-Amur region along Russia’s border with China.
Amur tigers Boris and Svetlaya, observed by a trail camera in 2018.Credit: ANO WCS/The New York Times
The scientists tracked the cubs until, more than a year after their release, something strange happened: Boris walked more than 200 kilometres, almost in a straight line, to where Svetlaya had made a home.
Six months later, Svetlaya gave birth to a litter of cubs.
While the strategy of releasing rescued cats raised in captivity to restore populations in the wild had proven successful with the Iberian lynx in Spain, it had never been tried with big cats.
But scientists working with the Wildlife Conservation Society say in a study published in the Journal of Wildlife Management that the successful release of rescued cubs like Boris and Svetlaya may, for the first time, become a viable option for restoring wild tigers to their historical range.
Estimates of the number of tigers left in Russia range from 485 to 750. But researchers say that the Russia-China border area, including the Pri-Amur area where Boris and Svetlaya live, could support hundreds more of the animals.
The reunited cats were not the project’s only successful reintroductions. Two hunters had found another female, Zolushka (or “Cinderella” in Russian), in a snow drift a few years earlier. After the conservationists returned her to the wild, an unknown male tiger showed up on a camera trap near where Zolushka had been released.
In such a vast area, it was an encounter of extraordinary good fortune. “Cinderella’s prince showed up and they lived happily ever after,” said Dale Miquelle, lead tiger scientist for the Wildlife Conservation Society and an author of the study. Zolushka and the male also produced a litter of cubs, the first known cubs to be born in that area since the 1970s.
Kolya Rybin, one of the authors of the study, examining the cub Boris, after capture and immobilisation.Credit: The New York Times
In all, Russian scientists raised 13 orphaned Siberian tiger cubs in captivity, avoiding any contact between the growing cubs and their human caretakers to prepare them for life in the wild. The team gradually introduced the cubs to live prey so they could learn how to hunt.
Also critical to the success was the timing of the cubs’ release: during spring when prey was plentiful.
One male cub failed the test of freedom. He wandered into China and preyed on domestic animals, including 13 goats in one shed in a single night. Russian scientists recaptured the young male and sent him to a captive-breeding program at a zoo.
But the remaining 12 proved they were able to hunt wild prey and to survive as well as wild tigers that had never spent time in captivity.
As the Pri-Amur population grows, the Russian-American team hopes it can join up with other tigers, including across the border in China. “The grand vision is that this whole area would be connected,” said Luke Hunter, executive director of the Big Cats Program at the Wildlife Conservation Society. “There’s lots of habitat that could be recolonised by tigers.”
With so much potential habitat across Asia – a 2023 study found there was about 700,000 square kilometres of potentially suitable habitat across Asia where tigers remained absent – the implications of this success are wide-ranging.
“These results indicate that it is possible to care for young cubs in a semi-captive environment, teach them how to hunt and to release them back into the wild,” said Viatcheslav Rozhnov, former director of the Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences and leader of the reintroduction project.
“These findings provide a pathway for returning tigers to large parts of Asia where habitat still exists but where tigers have been lost.”
The Russian-American team hopes that it can join up with other tigers, including across the border in China. Credit: naturepl.com / Edwin Giesbers/WWF
And just as Boris and Svetlaya’s unlikely partnership has proved critical to the project’s success, the Russian and American scientists hope their efforts may be a model for international conservation co-operation.
“It’s a testimony to how really good things can happen when you start working collaboratively irrespective of nationality and politics,” Miquelle said.
This article originally appeared in The New York Times.
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