Streaked Shearwater

The streaked shearwater is a species of seabird that breeds in colonies on uninhabited islands in the Oki Islands. The bird breeds on islands throughout Japan, with Ōshima in Hokkaido as the northern limit. It is around 49 cm in length, with a wing span reaching 120 cm. The upper parts of its body and wings are grey, with blackish brown spots from the forehead to the nape, increasing to form a sesame-salt pattern on the nape and white underwings. The hook-tipped bill is long and slender, and bluish in color.
During the day, the flock flies around the sea in search of fish to feed on. This bird earned its name due to its ability to shear water with its wings when flying close to the water.
The streaked shearwater nests in burrows, dug in ground with little gravel and a lot of soil. The entrance to their long, horizontal burrows is 15–20 cm wide, and the depth of the burrow is about 1 m. The birds lay eggs in the deepest part of the burrow, covered with leaves and twigs. Ohakajima Island, Hoshinokami-jima Island, and Okinoshima Island in the Oki Islands are well-known breeding grounds and have been designated as natural monuments.