Seasonal changes in body weight of female Asiatic black bears under captivity

Abstract

Though body weights of bears are known to change seasonally responding to nutritional conditions, there is little information on the body weight and nutritional condition of Asiatic black bears, Ursus thibetanus. We weighed seven female Japanese black bears, U. thibetanus japonicus, under captive condition from May to December, 1995. Although the body weights did not differ significantly between years, three seasonal phases were distinguishable according to the increase rate (rw). During Phase I, mean body weight increased gradually from May (46.2±4.4 kg, mean±SD, n=6) to August (57.3±3.5 kg, n=6: 5% <5%). Contrary, body weights increased rapidly during November and December (68.4±4.7 kg, n=5: 10%