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
Kumlien's gull Kumlien's gull Kumlien's gull ("Larus glaucoides kumlieni") is a large gull which breeds in the Arctic regions of Canada. It is migratory, wintering from Labrador south to New England and west across the Great Lakes. The species is named after the Swedish-American naturalist Thure Kumlien. It is a regular vagrant in small numbers to Britain and Ireland. It has variably been considered a full species, a subspecies of Thayer's gull, a subspecies of Iceland gull, and a hybrid between the aforementioned species, all of which are considered subspecies of the Iceland gull as of 2017. This taxon breeds colonially or