Home ranges of brown bears on the Kamchatka peninsula and Sakhalin Island

Territorial activity was studied using satellite tracking of four brown bears ( Ursus arctos ) in Kamchatka in 2005–2006 and three brown bears on Sakhalin in 2011–2012. The size of annual home ranges was 6.09–27.58 km 2 for females and 153.12 km 2 for males. The size of the nuclear zone of the annual home ranges did not exceed 1.68 km 2 . Seasonal home ranges were largest in August-September and smallest in May. The home ranges of two females in Kamchatka were significantly overlapped, the lesser degree of overlap was noted for two females on Sakhalin. The nature of the use of the study area by bears, essentially depends on the seasonal distribution of food, in particular salmon.