Swallow-tailed gull and hunting over the open oceans, and migrating eastward to the coasts of Ecuador and Peru. The swallow-tailed gull is unique among the gulls in feeding exclusively nocturnally, mostly on fish and squid which rise to the surface at night to feed on plankton. It leaves the colony as a flock at dusk, with a great deal of screaming and display. Calls and displays are quite different from other gulls, most resembling the vocalisations of the black-legged kittiwake and Sabine's gull. The loudest and most commonly heard call is an alarm referred to as "rattle-and-whistle", a gurgling scream made with
Brown-hooded gull of stealing from these birds is 3.5 times higher for the coots than the oystercatchers. They build floating nests among aquatic vegetation at the edges of ponds and lakes. Three to four eggs are usually laid. The black-headed duck has a brood parasite relationship with the brown-hooded gull in which a female will lay an egg in the nest of a brown-hooded gull with the intent of having the host gull incubate the egg instead of herself. Brown-hooded gull The brown-hooded gull ("Chroicocephalus maculipennis") is a species of gull found in Argentina, Brazil, Chile, the Falkland Islands, and Uruguay. Its