The Streaked Shearwater (Calonectris leucomelas) breeds in immense numbers on
islands of southern Japan (Izu, Ryuku, Daito and Senkuku Groups) which
forms the center of its breeding distribution. Also found on islands off
the coasts of Korea and China. Estimates for the Izu Islands are in the
order of 3-4 million birds. It is often the most abundant seabird to be
observed at sea around Japan. This shearwater is regarded as sacred
in Japan and is protected by law. The livelihood of residents and
fishermen on many of Japan's islands have depended on it for hundreds of
years; whether killing them for food, or following them out to sea where
they lead the fishermen to schools of fish. Some mortality occurs when
birds are trapped in trawl or gill-nets, and from oil pollution.
Significant weather-related wrecks (large scale die-offs) occur
occasionally on the mainland.
Although graceful and swift at sea, they appear awkward on land. Returning to colonies at
night, they land by falling through the trees to the ground where they
nest in burrows and crevices. They often hurl themselves into the air from
treetops in order to get airborne again. Streaked Shearwaters resemble
Cory’s Shearwater in size and coloration, but they are less heavy with a
thinner bill. The whitish head contrasts with dark brownish streaking on
the crown and nape. After breeding, birds migrate to tropical waters of the east and southern China Seas, Philippines,
Indonesia and Indian Ocean. Adults leave prior to young. Many reach Papua
New Guinea and the Coral Sea, some getting as far south as Sydney,
Australia or Sri Lanka.
Photo by Koji Ono, taken on Biro Island, off Kyushu Island.
Dr. Koji Ono is a seabird researcher in Japan,
and an ardent wildlife photographer. More information on Japanese seabirds
can be found at the website for the Japan Alcid Society (English
To learn more about other seabirds, browse the Seabird Flash Cards on the Seabird Page of this website.