Brown-headed Gull

Brown-headed Gull (Chroicocephalus brunnicephalus) is a medium gull with a pale brown breeding hood, red bill and legs, grey back and black-tipped wings. Body shape, bill structure, plumage pattern and voice provide the strongest field characters. Age, sex and season may alter its appearance, so identification should combine several features and careful direct comparisons with similar species in the same habitat (Wikipedia, general species account).

It breeds colonially on high Asian lakes and winters on coasts and wetlands, feeding on invertebrates, fish and refuse. Its movements and social behaviour vary through the year, with breeding birds generally more dispersed and non-breeding birds gathering where food is concentrated. Japanese records place it within the country's documented avifauna as a resident, migrant or visitor (Wikipedia, general species account; Wildlife of Japan occurrence records).