Fallen leaves and unpalatable plants as alternative foods for sika deer under food limitation

Feeding behavior and rumen contents of sika deer (Cervus nippon Temminck) u nder food limitation were studied on Nakanoshima Island, Hokkaido. During t he phase of population growth, the deer subsisted on tree bark and twigs, d eciduous leaves and dwarf bamboos (Sasa SPP) in the winter. After a crash i n population, the deer began feeding on the fallen leaves of deciduous tree s and continued to do so throughout the year. They also ate unpalatable pla nts Cephalotaxus harringtonia var. nana Rehd., Senecio cannabifolius Less. and Cynanchum caudatum Maxim. as winter foods, which used to remain untouch ed by deer, and had accordingly expanded their distributions, following a d ecrease in the amount of dwarf bamboos available. These facts suggest that sika deer drastically shift their foods and exploit alternative foods under conditions of food limitation.