The Carcass Records of Large-sized Larus sp. with Yellow Legs on Teuri Island, Hokkaido, Japan

Abstract

We reported characteristics of external morphology and DNA sequence from the carcass of a large-sized gull with yellow legs recovered at Teuri Island, Hokkaido, Japan. According to Olsen & Larsson (2003), based on the tone of the upperwings and mantle and the pattern of the primary tips the carcass sample was identified as Larus heuglini, but could not be identified at the subspecies level. Sequence variation in the cytochrome b and control region gene of the carcass sample agreed with common types of closely-related taxa (fuscus, heuglini, barabensis, or taimyrensis). Our study underscored the difficulty in identifying large white-headed gulls accurately even when based on quantitative data such as those obtained from carcass samples or DNA sequences. Further quantitative studies on inter- and intra-population variations in external morphology of birds at each breeding site are needed.