The world’s rarest big cat recently emerged in the Russian Far East, proving this critically endangered leopard is still hanging tough. Researchers from the Wildlife Conservation Society (WCS) captured and released “Alyona,” a female Far Eastern leopard, in Russia at the end of October. She is one of an estimated 25 to 40 of these big cats in existence.

The capture was made in Primorsky Krai along the Russia-China border. Scientists from the Russian Academy of Sciences Institute of Biology and Soils (IBS) were also on the scene. The team is working with Wildlife Vets International, National Cancer Institute, and the Zoological Society of London to evaluate the health and potential effects of inbreeding for this tiny population. Experts believe it contains no more than 10 to 15 females. Three leopards captured previously in 2006 and 2007 all exhibited significant heart murmurs, which may reflect genetic disorders.

Alyona was in good shape and weighed a healthy 85 pounds. A preliminary health analysis pegged her as 8–10 years old. After the physical exam, she was released.

To help increase genetic diversity in the Far Eastern leopard population, scientists are considering translocating leopards from other areas. A similar effort helped revive the Florida panther, when animals were relocated from Texas. Today, Florida panthers have risen from fewer than ten individuals to a population of approximately 100.

During the past 100 years, poaching and habitat loss have driven the Far Eastern leopard to near extinction. However, camera-trapping and snow-tracking surveys show the population has remained stable for the past 30 years, though with a high turnover of individuals. If inbreeding and disease can be kept in check, WCS and its partners believe there is great potential for increasing survival rates and habitat recovery in both Russia and northeast China.

WCS’s work to protect Far Eastern leopards receives funding from the U.S. Fish & Wildlife Service’s Rhinoceros and Tiger Conservation Fund, National Fish and Wildlife Foundation’s Save the Tiger Fund, and U.S. Forest Service International Program. The Far Eastern leopard is listed under CITES (Convention on International Trade in Endangered Species), which protects it against illegal trade for fur and medicinal purposes.