Pétrel de Masatierra

Identification

Masatierra petrel grows to a length of about 26 centimetres (10 in). Its cap and mask are dark grey while its forehead is white. It has dark grey plumage on its upperparts with a distinctive "M" mark, a paler grey partial collar and a white throat, belly and under wing-coverts. When seen from below, the wings have black tips and black trailing edges.

Taxonomie

Nom scientifique

Pterodroma defilippiana

Autorité

(Giglioli & Salvadori, 1869)

Ordre

Procellariiformes

Famille

Procellariidés

Genre

Pterodroma

Répartition et habitat

Masatierra petrel spends the greatest part of the year at sea in the eastern Pacific Ocean south of the equator where the Humboldt Current causes a major upwelling of nutrient-rich cold water. Here the bird feeds by skimming across the surface of the water and scooping up prey on the wing. It nests in two island groups off the coast of Chile. On the Desventuradas Islands, the largest colony is on San Ambrosio where more than 10,000 birds were estimated to be present in 1970. San Félix also had 150 to 200 nesting pairs at that time. On the Juan Fernández Islands, the bird is no longer believed to be nesting on Robinson Crusoe Island but Santa Clara Island had a few hundred birds present in 1991, a number not likely to increase because there is limited availability of suitable nesting sites on the island.

Aire de reproduction

PO : San Ambrosio and San Felix (Desventuradas Is., far w of nc Chile) and Santa Clara (sw of Robinson Crusoe=Mas a Tierra, Juan Fernandez Is., far w of c Chile)

Aire hors reproduction

to coastal waters of s Peru and n, c Chile and to Pitcairn group (e Polynesia)

Migration

Complete migrants

Conservation

Tendance de la population

stable