Shorebirds and seabirds' ecology and conservation

Abstract

Shorebirds and seabirds of the order Charadriiformes are among the most diverse and conspicuous birds inhabiting Bahia Blanca Estuary. This order consists of three suborders, Charadrii, Scolopaci, and Lari, represented in the estuary by 46 species. Most shorebirds breed in both the north-and the south-end of the Americas, undertaking short-to long-distance migrations to reach Bahia Blanca during the non-breeding season. In contrast, most seabirds are residents or partial migrants. The importance of Bahia Blanca Estuary as a breeding area is especially highlighted for Olrog's gull (Larus atlanticus), a species with an adverse conservation status of which more than 60% of its global population breeds there. About 35% of the species covered here have decreasing population trends, with pollution and the expansion of invasive alien species being some of the most important threats at the local scale. In this chapter we detail some of the most relevant aspects of the ecology of shorebirds and seabirds in Bahia Blanca Estuary, including some of their morphological and physiological adaptations. We finally discuss some of the major conservation challenges they face.