Swallow-tailed Gull

Overview

The swallow-tailed gull (Creagrus furcatus) is an equatorial seabird and the only species in the genus Creagrus. It is the only fully nocturnal gull in the world, spending most of its life flying and hunting over the open ocean.

Identification

• Adult plumage is black on the head during breeding season with a bright red fleshy eye rim, turning white with a black eye rim outside breeding season.
• Features a grayish upper breast, gray mantle, and black wingtips.
• Possesses a mostly black bill with a contrasting white tip.
• Vocalisations include a 'rattle-and-whistle' alarm call and a rapid 'kweek' greeting call between mates.

Habitat

This bird is a near-endemic breeder of the Galápagos Islands, with some pairs nesting on Malpelo Island off the coast of Colombia. When not breeding, it is totally pelagic, migrating eastward to the coasts of Ecuador and Peru.

Diet

The swallow-tailed gull feeds exclusively at night on small fish and squid that rise to the surface to feed on plankton. It leaves its colony as a flock at dusk to hunt in the open ocean.

Did you know?

The species is the only fully nocturnal gull, possessing eyes that are larger in size and volume than any other gull and featuring a tapetum lucidum to enhance night vision.