To determine the diet selection of a forest-dwelling ungulate, the Japanese serow (Capricornis crispus), we investigated its diet composition in relation to forage availability using direct observation of foraging behavior for individually identified three adult males in three seasons (spring, autumn, and winter) over two years in the cool temperate forests of Mt. Asama, central Japan. We found that they selected deciduous broad-leaved trees (leaves, fruits, twigs, and buds), forbs (leaves and flowers), and ferns (leaves) and avoided leaves of graminoids and coniferous trees throughout the study periods. Our findings clearly indicate that serows are typical browsers, selecting more digestible food plants. Unexpectedly, our analyses indicated a higher selectivity for ferns than deciduous broad-leaved trees, especially in winter. We also showed that diet composition was significantly different among individuals, but there was little difference in diet selectivity among individuals, suggesting that inter-individual differences in diet are affected by forage availability within each individual's home range.

Published online 14 February, 2024; Print publication 30 April, 2024