Aspectos da biologia reprodutiva de Pterodroma arminjoniana (Giglioli & Salvadori,1869) (Aves: Procellariidae) na ilha da Trindade, Atlântico Sul

Abstract

The Trindade Petrel Pterodroma arminjoniana (Giglioli & Salvadori, 1869), the only representative of the genus to breed in Brazil, was studied at the oceanic island of Trindade, South Atlantic (20º 30' S, 29º 19' W), between 1988 and 1993. According to the results obtained after 1270 hours of observations, the breeding habits of P. arminjoniana closely resembles those of other species of Pterodroma regarding the extensive incubation period, the slow growth of chicks and the irregular feeding of the young by the parents. At Trindade, P. arminjoniana breeds throughout the year inside small caves or among scattered rocks on the ground. The clutch is composed of a single egg which is incubated by both parents for 52 days. The chick is born fully covered by a thick layer of down, and it becomes independent in 100 days. Although a rather common bird in Trindade, P. arminjoniana may have been adversely affected by the human presence in the island, since some of its breeding grounds are quite vulnerable to pigs, cats and other introduced mammals.