Common Sandpiper

Common Sandpiper (Actitis hypoleucos) is a small brown-and-white shorebird with a distinctive white shoulder notch, short legs and constantly bobbing rear. 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 feeds on insects and other invertebrates along stony freshwater margins and migrates to rivers, wetlands and coasts. 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).