Seasonal variation in fleshy fruit use and seed dispersal by the Japanese black bear (Ursus thibetanus japonicus)

• Published in: Ecological research Vol. 23; no. 2; pp. 471 - 478
• Main Authors: Takahashi, Kazuaki, Shiota, Tadatoshi, Tamatani, Hiroo, Koyama, Masaru, Washitani, Izumi
• Format: Journal Article
• Language: English
• Published: Japan Japan : Springer Japan 01.03.2008; Springer Japan; Blackwell Publishing Ltd
• Subjects: Animal behavior; Autumn; Bears; Behavioral Sciences; Biomedical and Life Sciences; birds; Deciduous forests; Dispersal; Ecology; Evolutionary Biology; Fleshy-fruited plants; Food plants; foraging; Foraging behavior; Forestry; frugivores; Fruit size; fruiting; Fruiting phenology; Fruits; Japan; Japanese black bear (Ursus thibetanus japonicus); Life Sciences; Note and Comment; Plant Sciences; Plant species; seasonal variation; Seasonal variations; Seed clump; Seed dispersal; Seeds; shrubs; Species composition; species diversity; summer; Trees; Ursus thibetanus; Zoology; Japan; Fleshy-fruited plants; Seed clump; Japanese black bear; ); Fruiting phenology; Seed dispersal; Fruit size
• DOI: 10.1007/s11284-007-0382-z
• ISSN: 0912-3814

Fruit use by the Japanese black bear (Ursus thibetanus japonicus) and seed clumping in bear scat were studied in central Japan using fecal analyses. Between May and November 2003 and 2004, the life form and fruit size of plants consumed by bears and the species composition and intactness of seeds contained in scat were examined in five transects (approximately 10 km x 10 m) in broad-leaved deciduous forests. In 2003, scats with seeds were found only in the autumn, when fruiting trees and shrubs were abundant. In 2004, scats with seeds occurred intermittently from the summer, when fruiting plants were rare, up to the autumn. Yearly and seasonal variation in fruit use reflects the opportunistic foraging behavior of Japanese black bears. Seven of the nine plant species detected in scats had medium-sized fruits (6-15 mm width), whereas the other two species had relatively large fruits (20-100 mm width). In total, 14,492 seeds were detected, of which 97.6% were intact; the remainder were damaged. Intact seeds of one or two species were found in each scat. The number of intact seeds per scat ranged from 1 to 5476. Japanese black bears seldom digest ingested seeds, thereby contributing to the seed dispersal of their food plants, including species with fruits that are too large to be swallowed by frugivorous birds.