Feeding behaviors of masked grosbeak eophona personata on acorns of fagaceous species

Abstract

Over a 2-day period, 30-70 Grosbeaks Eophona personata were observed feeding on acorns of several fagaceous species (Quercus glauca, Castanopsis cuspidate and its variation C. cuspidate var. sieboldi) in the understory of evergreen broadleaved forest at Funaokayama Hill, Kyoto City. Grosbeaks cracked the cupula and pericarps of acorns with their bills, and fed only on the embryos and cotyledons inside. This feeding behavior on synzoochorous seeds is very similar to that observed when feeding on anemochorous and endozoochorous seeds. ©Yamashina Institute for Ornithology.