The techniques used to restore the tiger population are highlighted in a new study in the Journal of Wildlife Management which can be found HERE.
In addition to highlighting this Russian success story, the study outlines a pathway for the restoration of tigers in many other parts of Asia where they have been lost.
The study specifically examined the success of rehabilitating and releasing orphaned cubs to restore tigers to their historical range in Russia. The efforts were led by the Russian Academy of Sciences and Russian Geographical Society, with WCS playing a key role in saving orphaned cubs in the wild and then following them after release.
The study followed the fate of six tiger cubs who were found as orphans in the forests of the Sikhote-Alin Mountains of Russia—the last stronghold of tigers in that country. The Cubs had been kept in specially designed enclosures where contact with humans was kept to an absolute minimum, and at appropriate ages, the cubs were offered live prey to learn how to hunt. The Wildlife Conservation Society’s Bronx Zoo and other partners advised on ways to raise and keep the cubs so they would not be dependent on humans.
The cubs were subsequently released as subadults (at least 18 months old) into the Pri-Amur region of Russia, west of the Sikhote-Alin and part of the original range of tigers, specifically in an attempt to restore a population there.
The study collected data on the success of these newly released cubs to hunt and secure wild prey in their new homes. Using location data recorded by GPS collars affixed to the tigers before release, researchers were able to find 132 kills made by orphaned cubs and compare the results to wild Amur tigers studied in the core population of the Sikhote-Alin Mountains.
Dale Miquelle, lead author of the study, said, “Basically the data demonstrated that orphaned cubs, raised in captivity and released, were just as good as wild tigers at hunting, targeting the same types of wild prey, and very rarely killing livestock. This success demonstrates that tigers with proper isolation from humans and provided the opportunity to learn to hunt, can be successfully re-released into the wild. But this process requires great caution and attention to details in preparing cubs for this journey.”
The need for such caution was demonstrated with one exception in this experiment: one re-wilded tiger wandered into China, where wild prey was sparse, and killed multiple domestic animals, including 13 goats in a shed in one night. Upon return to Russia, this tiger was captured, removed from the wild, and sent to a zoo. The other 5, as well as 8 more individuals that were released in the Pri-Amur, but not as intensively studied, have thrived in the wild, and succeeded in producing at least six litters of no less than 12 cubs, resulting in a growing population.
Prof. Viatcheslav V. Rozhnov, former Director of the Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences, and leader of the project that introduced tigers into the Pri-Amur, said, “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. These findings provide a pathway for returning tigers to large parts of Asia where habitat still exists but where tigers have been lost. We hope other practitioners can adopt these approaches and learn from our efforts to restore tigers to areas where they have been lost. We, in collaboration with our Chinese colleagues, are in fact already currently expanding these efforts with a similar project in nearby Heilongjiang Province, China.”
Tigers currently exist in an estimated 8% of their historic range, with much of their original habitat lost to human development. But another recent study by WCS scientists and collaborators led by Dr. Eric Sanderson demonstrated that there are over 700,000 km2 of “empty” habitat that is suitable for tigers across Asia, but where tigers are absent. Of course, there are obstacles to restoration: reasons for original extirpation must be understood and mitigated; prey populations must often be recovered; and hunting pressures reduced.
Til now, both researchers and conservation practitioners were unsure how to bring tigers back to areas where they have been lost. With 4,500 or fewer tigers scattered across 63 remaining landscapes, capture and release into new areas could threaten the source populations. Tigers in the world’s zoos are not “equipped” with the skills needed to survive in the wild and do not retain the innate fear of humans needed to avoid conflict.
This study provides the framework for rearing cubs in semi-captive conditions and preparing them for the wild.
Dr. Luke Hunter, Executive Director of the WCS Big Cats Program, said: “This study represents a tantalizing new development in expanding the ‘toolbox’ for conservationists to return tigers to those parts of Asia where they have been lost. The team was scrupulous in preparing young cubs for life in the wild, especially in ensuring they did not habituate to humans. Their careful approach succeeded and paves the way for more reintroduction attempts—not only of tigers, but of other big cats as well.”
Added Miquelle: “And perhaps just as importantly, this work demonstrated the power of collaborative efforts—people from more than 8 organizations and multiple countries joined hands to make the rehabilitation and release of these tiger cubs a reality, not only saving the cubs from starvation, or lives in confinement, but for the first time using orphaned cubs as the source for restoring tigers to a region where they had been lost. These fantastic results would not have been possible without such broad-reaching collaboration.”
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Wildlife Conservation Society (WCS)
WCS combines the power of its zoos and an aquarium in New York City and a Global Conservation Program in more than 50 countries to achieve its mission to save wildlife and wild places. WCS runs the world’s largest conservation field program, protecting more than 50 percent of Earth’s known biodiversity; in partnership with governments, Indigenous People, Local Communities, and the private sector. It’s four zoos and aquarium (the Bronx Zoo, Central Park Zoo, Queens Zoo, Prospect Park Zoo, and the New York Aquarium ) welcome more than 3.5 million visitors each year, inspiring generations to care for nature. Visit: newsroom.wcs.org. Follow: @WCSNewsroom. For more information: +1 (347) 840-1242. Listen to the WCS Wild Audio podcast HERE.