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Wedge-tailed Shearwater

Ardenna pacifica

Length: 16-18 inches Wingspan: 40 inches Seasonality: Non-resident in South Dakota
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.

Wedge-tailed Shearwater - Ardenna pacificaThe 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.

Interactive eBird map: Click here to access an interactive eBird map of Wedge-tailed Shearwater sightings

Similar Species: Sooty Shearwater, Short-tailed Shearwater, Buller's Shearwater

Conservation Status: Populations of Wedge-tailed Shearwater may be decreasing, but they are still widespread and common in many areas.  The IUCN lists the Wedge-tailed Shearwater as a species of "Least Concern".

Further Information: 1) BirdLife International - Wedge-tailed Shearwater

2) Kauai Endangered Seabird Recovery Project - Wedge-tailed Shearwater

3) Audubon Guide - Wedge-tailed Shearwater

Photo Information: Photo taken by Amy McAndrews - February 9th, 2009 - Huatulco, Oaxaca - Photo licensed under Creative Commons Attribution NonCommercial 2.0 Generic license.


Click below for a higher-resolution map
Wedge-tailed Shearwater - Range Map
South Dakota Status: Non-resident in South Dakota

Additional Wedge-tailed Shearwater Photos (coming soon!!)