Sight Record of a White-winged Black Term at Taiki, Hokkaido

Abstract

A single summer plumage White-winged Black Tern Sterna leucoptera was observed at the mouth of the Rekifune River, Taiki, Tokachi Distr., Hokkaido, on 22-23 May 1986. It dove frequently and caught small fish which looked like fry salmon, hovered occasionally, and alighted slowly on the water surface and flew up at once after putting the leg into the water. It appeared that the hovering time of the bird was short compared to a Common Tern Sterna hirundo. Moreover, the bird sometimes showed diving behavior like an Osprey Pandion haliaetus. These habits seemed to be different from those previously reported from Japan (cf. TAKANO 1981).