Little Shearwater - Puffinus assimilis baroli (Bonaparte 1857) (Portuguese Common Name - Pintainho) Breeding Of the marine birds breeding in Portugal, the Little Shearwater breeds earliest in the year. The breeding season starts in December, eggs are laid from February and are incubated through March. Around May, the juveniles leave the nests for sea. This species does not make long distance migrations, but remains close to the islands where it breeds. Distribution and population size This species, of which 8 subspecies have been identified, is distributed across the Atlantic, Pacific and Indian Oceans. The subspecies found in Portugal, Puffinus a. baroli is endemic to Macaronesia, and is found exclusively on the archipelagos of Madeira, the Azores and the Canaries. Puffinus s. boydi occurs in Cape Verde. The Little Shearwater is not abundant on the Archipelago of Madeira, except on the Selvagens where the population has over 2,050 pairs (Oliveira & Moniz 1995) and appears to be stable. On the Azores there are around 1,500 pairs distributed throughout the Archipelago. Identification In the seas of Macaronesia the Little Shearwater is most likely to be confused with the Manx Shearwater (Puffinus puffinus), and can be distinguished from that shearwater by its smaller size and by the fact that the black plumage of the head does not come below the eyes: the eyes of the Little Shearwater stand out against the pale face. Habitat The Little Shearwater nests on cliffs of small islands and islets. The nests are built in cavities and holes in rocks, such as in walls or under loose stones. Conservation Threats As with the majority of marine birds, the principal threats relate to the presence of introduced mammals near the breeding sites, whether rats, cats or others. Another limiting factor that has been identified is competition for nesting sites with other species, which results in reduced breeding success: the rate of breeding failure can reach 34% (Moniz et al 1997). Conservation status and legal instruments of protection The Little Shearwater is Vulnerable and dependent on management, and is included in Annex I of the Birds Directive and Annex II of the Berne Convention. A significant part of its breeding habitat is included in Annex I of the Habitats Directive. Current state of knowledge in Portugal The only data available about this species in Portugal relates to population censuses during the breeding season. Little is known about the majority of the colonies. Moniz, P.; L. Monteiro e P. Oliveira 1997. The Little Shearwater. In Hegemeijer, W. e M. Blair (eds) 1997. The EBCC Atlas of European Breeding Birds. Their Distribution and Abundance. T & AD POYSER. Oliveira, P. e P. Moniz 1995. Breeding Chronology of the Little Shearwater Puffinus assimilis, in Selvagem Grande. Proc. of the 5th. International Seagroup Conference. Glasgow. |