Red Knot

Red Knot (Calidris canutus) is a robust sandpiper with short dark legs, straight bill and brick-red face and underparts in breeding plumage. 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 field comparisons with similar species in the same habitat (Wikipedia, general species account).

It breeds on High Arctic tundra and forms dense migratory flocks on tidal flats, feeding mainly on molluscs. 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).