Swinhoe's Storm Petrel

Swinhoe's storm petrel is a small, all-brown seabird, 18–21cm long with a wingspan of 45–48cm, distinctly larger than the European storm petrel. It is essentially dark brown in all plumages and has a fluttering flight, pattering on the water surface as it picks planktonic food from the ocean surface (Wikipedia, general species account).

It breeds on islands in the north-west Pacific off the Russian Far East, China, Japan and Korea, for example on Verkhovsky Island (about 7,500 pairs) south of Vladivostok, in Japan, and on six or seven islets in South Korea. It nests in colonies close to the sea in rock crevices and lays a single white egg. It spends the rest of the year at sea, ranging into the Indian Ocean and the Arabian Sea (Wikipedia, general species account).