Pterodroma externa

Overview

The Juan Fernández petrel (Pterodroma externa) is a large species of seabird in the family Procellariidae. It is endemic to Chile, nesting exclusively on a single island in the Juan Fernández Archipelago.

Identification

• A large gadfly petrel measuring 43 cm in length with a wingspan of 95–97 cm.
• Upperparts are dark brownish-grey with a black M-shaped marking across the extended wings, while underparts are white with black-edged wing undersides.
• The face is white with a black 'cap' extending below the eyes, and feet are yellow with dark brown tips.

Habitat

Breeding habitat consists of high-elevation ridges above 750 m on Isla Alejandro Selkirk, where the birds dig burrows to raise their young. During the non-breeding season, they forage in equatorial currents as far north as the Hawaiian Islands.

Diet

Chicks are fed a diet consisting mainly of regurgitated fish and squid by their parents. During the breeding season, adults forage in waters surrounding Isla Alejandro Selkirk and Isla Robinson Crusoe, as well as coastal Chile.

Did you know?

The breeding population was estimated at one million pairs in 1985–86, with a total global population potentially reaching three to five million birds.