ID Keys: Dark brownish-gray upperparts, white underparts, white
underwings with dark edging, wedge-shaped tail, thin grayish bill.
There is also a "dark-phase" adult that has nearly all brownish-gray
plumage.
The
Wedge-tailed Shearwater is a large shearwater species of the tropical, warm
waters of the Pacific and Indian Oceans. They are only extremely rare
visitors to North America, with a handful of sightings off the west coast of
the United States. They are closely related to the
Buller's Shearwater.
Habitat
Nests on islands with suitable soil for
building nest burrows. They will also sometimes nest on rocky islands,
using crevices in the rocks as their "burrows". Outside of the
breeding season, Wedge-tailed Shearwaters are usually found over warm ocean
currents.
Diet
Feeds mostly on fish, squid, and small
crustaceans.
Behavior
Forages by flying low over the water's
surface, dipping down to retrieve food items when spotted, or making dives
and swimming underwater in pursuit of prey. Will also swim along the
ocean's surface and grab prey items, or dive from a swimming position.
Nesting
Nests in a burrow, often using the same
burrow year after year. The female lays a single egg, and both parents help
to incubate it. Both parents help feed the nestling after it hatches,
with regurgitated squid and stomach oils the most common food provided.
Song
Usually silent away from breeding grounds,
but they can be very vocal while nesting, with a variety of groaning and
moaning sounds. Their vocalizations while nesting have earned them the local
nickname of the "moaning bird" in some locations.
Migration
Found throughout much of the tropical
Pacific and Indian oceans, with scattered nesting sites including islands in
the Indian Ocean, islands near Australia, islands off of Japan, and the
Hawaiian islands. They disperse across much of the tropical Pacific
Ocean after the breeding season.
