Lesser Sand-Plover

Lesser Sand-Plover (Charadrius mongolus) is a compact plover with short dark bill and, in breeding plumage, chestnut breast and black facial markings. 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 on Asian uplands and tundra and migrates to tidal flats and beaches to feed on worms and crustaceans. 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).