抄録
We examined the food contents of the gizzard of an adult male Harlequin Duck Histrionicus histrionicus collected on 8 March 1979 at Enoshima Is., Miyagi Pref., where up to 100 birds winter every year. A decapod Oedignathus inermis (Crustacea, Anomura) formed the bulk of the food, although Polyplacophora, Gastropoda and someothers were also identified (Table 1). Most of the prey inhabit the rocks of the intertidal or undertidal zones, where Harlequin Ducks spend most of their time for feeding.