Photo First: Rare Tiger Family Portrait

For the first time, conservationists have spotted an Amur tiger dad leading his family along a snowy trail in Russia's Far East forests.

There are fewer than 500 of the rare Amur tigers left in the wild, according tothe Wildlife Conservation Society. The endangered species lives in remote, mountainous territory that makes it difficult to watch the tigers and monitor their natural behavior. So researchers use remotely activated camera traps to help catch the tigers as they hunt, play and move through the vast territory of Russia's Sikhote-Alin Biosphere Reserve and Udegeiskaya Legenda National Park (two adjacent protected areas).

The new photos from the Wildlife Conservation Society show a family of five Amur tigers padding through the snow this winter, lined up from large to small like nesting dolls. Although family group behavior has been seen in Bengal tigers many times, this is the first evidence of male Amur tigers in a family setting, rather than as solitary cats, researchers said. [Iconic Cats: All 9 Subspecies of Tigers]

"We have collected hundreds of photos of tigers over the years, but this is the first time we have recorded a family together," Svetlana Soutyrina, deputy director for scientific programs at the Sikhote-Alin Biosphere Reserve, said in a statement. "These images confirm that male Amur tigers do participate in family life, at least occasionally, and we were lucky enough to capture one such moment."

The 21 photos show the tiger family walking in front of the same camera within 2 minutes.

"These photos provide a small vignette of social interactions of Amur tigers, and provide an evocative snapshot of life in the wild for these magnificent animals," Dale Miquelle, Russia director for the Wildlife Conservation Society, said in the statement.

The camera trap was part of a camera network installed throughout the Sikhote-Alin Biosphere Reserve and Udegeiskaya Legenda National Park during a 2014-2015 population count of the endangered Amur tigers. Every 10 years, hundreds of volunteers survey the remote region to estimate the tiger population. In 2005, there were 430 to 500 tigers remaining in the wild, according to the survey.

Amur tigers once ranged throughout the Russian Far East, northern China and Korea. But by the 1940s, hunting and habitat loss brought their numbers down to only 40 tigers left in the wild. Thanks to conservation efforts, the population rebounded to around 500 by the 1980s, according to the Wildlife Conservation Society. However, the tiger population is restricted to reserves in the Russian Far East and China.

Camera traps have also helped monitor the population of another rare Russian cat - the Amur leopard. Photos and video footage from the World Wildlife Fund suggest the number of Amur leopards has nearly doubled, from 30 in 2007 to 57 in 2014.

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