The Siberian tiger (Panthera tigris tigris) is a tiger population in the Far East, particularly the Russian Far East and Northeast China. This population inhabits mainly the Sikhote Alin mountain region in southwest Primorye Province in the Russian Far East. The Siberian tiger once ranged throughout Korea, north China, Russian Far East, and eastern Mongolia. In 2005, there were 331–393 adult and subadult Siberian tigers in this region, with a breeding adult population of about 250 individuals. The population had been stable for more than a decade due to intensive conservation efforts, but partial surveys conducted after 2005 indicate that the Russian tiger population was declining. An initial census held in 2015 indicated that the Siberian tiger population had increased to 480–540 individuals in the Russian Far East, including 100 cubs. This was followed up by a more detailed census which revealed there was a total population of 562 wild Siberian tigers in Russia.