Buff-breasted Sandpiper

Buff-breasted Sandpiper (Calidris subruficollis) is a graceful buff-coloured sandpiper with small head, dark spotted wings and yellowish legs. 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 Arctic tundra, where males display at leks, and migrates to short grasslands in South America. 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).