COMPOSITION AND FINALITY OF THE MIXED FLOCKS IN SEABIRDS AT ILHA COMPRIDA ISLAND, (SÃO PAULO, BRAZIL).

Shorebirds are a diverse group of mostly small, long-legged, gregarious birds that live along shorelines and inland waterways worldwide. They fly swiftly in large flocks migrating long distances between their seasonal ranges. The visual impression one gets is of speed and numbers, as entire flocks of tens of thousands of shorebirds are able to elude the fastest of winged predators (1). Shorebirds typically have long, slender legs and bills, relatively long, pointed wings, short tails, and a streamlined body. These features reflect a lifestyle of wading in water, marshes, or mudflats. Shorebirds primarily probe for burrowing invertebrates for food. They also make long-distance migrations between summer breeding and winter foraging areas which requires great strength and endurance. Most shorebirds are commonly found in tidal environments where they spend roughly half of their lives feeding. The rest is spent in flight, on migration, or living in wet meadows or upland grassy fields (2). In Ilha Comprida, 18 species of shorebirds occur regularly. Most occur during the nobreeding season. Except for a few species, shorebirds are grouped into two large families: the Charadriidae (plover family), Scolopacidae (sandpiper family) and coastalbird in Laridae (Gulls and terns). The two groups can generally be distinguished from each other by their feeding habits. Plovers with their large eyes feed by sight, using a run-peck-run strategy. Sandpipers have small eyes but specialized bills that they use as probes, employing the "sewing machine" method of continuous searching. Shorebird diets are quite varied and change with the seasons and the habitat. In this work we provides the record of composition and finality of the mixed flocks in shorebirds and coastalbird on Ilha Comprida Island, (São Paulo, Brazil)