Abstract
The Japanese black bear Ursus thibetanus japonicus, a large terrestrial mammal inhabits Honshu, Shikoku and Kyushu islands of Japan. However, Kyushu populations face extinction while populations on Shikoku island, in regions of Chugoku, and on the Kii peninsula are endangered. Ecological surveys such as direct observation, fecal analysis after field-sign detection and radio-tracking were carried out on Japanese black bears in Shirakawa Village, Gifu Prefecture in 1990-1994. Food habits of Japanese black bears in the spring and autumn related to the beech forest habitat of Shirakawa Village. The bears ate flower buds and seeds of the beech in the beechnut high-yield year while they ate the other food in the beechnut low-yield year. Mean home range sizes of Japanese black bears were found to be 6.4 km^2 and 3.1 km^2 in male and female bears, respectively. Studies on reproductive physiology of Japanese black bears, which were conducted under captive condition, determined that male bears exhibit remarkable seasonality in reproduction and that female bears have species-specific characteristics of reproduction including delayed implantation and parturition during hibernation. These findings suggest that an adequate feeding environment should be secured for the reproductive success and conservation of the Japanese black bear.
