Sooty Tern - Ecology

Ecology

Sooty Terns breed in colonies on rocky or coral islands. It nests in a ground scrape or hole and lays one to three eggs. It feeds by picking fish from the surface in marine environments, often in large flocks, and rarely comes to land except to breed, and can stay out to sea (either soaring or floating on the water) for 3 to 10 years.

This bird is migratory and dispersive, wintering more widely through the tropical oceans. It has very marine habits compared to most terns; Sooty Terns are generally found inland only after severe storms. The Field Museum, for example, has a male specimen which was found exhausted on August 2, 1933 on the slopes of Mount Cameroon above Buea, about 1000 m (3,500 ft) ASL, after foul weather had hit the Gulf of Guinea. This species is a rare vagrant to western Europe, although a bird was present at Cemlyn Bay, Wales for 11 days in July 2005.

It is also not normally found on the Pacific coasts of the Americas due to its pelagic habits. At Baja California, where several nesting locations are offshore, it can be seen more frequently, whereas for example only two individuals have ever been recorded on the coast of El Salvador - one ring recovered in 1972, and a bird photographed on October 10, 2001 at Lake Olomega which was probably blown there by a storm . Hurricanes can also devastate small breeding colonies, as has been surmised for example for the Sooty Tern nesting sites on cays off the San Andrés Islands of Colombia.

An exceptionally common bird, the Sooty Tern is not considered threatened by the IUCN.