seabird

A seabird is a bird whose ecology is closely tied to the marine environment. Most seabirds spend a substantial portion of their lives at sea, feeding in oceans and returning to land mainly to breed. They occur worldwide, with particularly high diversity in temperate and polar regions. Notable seabird groups include albatrosses, petrels and shearwaters (order Procellariiformes), gulls and terns (Laridae and allied families), penguins (Sphenisciformes), auks such as puffins, and cormorants and shags (Phalacrocoracidae), as well as frigatebirds and boobies in some regions.

Adaptations common to many seabirds include specialized salt glands to excrete excess salt from seawater, lightweight yet strong wings adapted for long-distance flight or dynamic soaring, and buoyant, waterproof plumage. Many feed by surface-seizing or plunging from the air, while others are adept divers. Some species are highly pelagic and undertake long migratory trips, whereas others are coastal or island-bound. Reproduction often involves colonial nesting on remote islands or cliffs, with long parental care and typically small clutches—often one egg—reflecting their high adult survival.

Ecology and behavior vary widely among groups. Diets usually consist of fish, squid, and crustaceans, and foraging strategies range from surface feeding to deep diving. Some seabirds engage in kleptoparasitism, stealing food from others.

Conservation concerns for seabirds are pronounced, including habitat loss on breeding islands, introduced predators, bycatch in longline and other fisheries, plastic pollution, oil spills, and climate-driven changes in prey availability. Protection efforts focus on island restoration, bycatch reduction, pollution mitigation, and international cooperation for marine and terrestrial habitats.