Ogilvie-Grant and Forbes, 1899
The Socotra Cormorant (Phalacrocorax nigrogularis) is a threatened species of cormorant that is endemic to the Persian Gulf and the south-east coast of the Arabian Peninsula. It is also sometimes known as the Socotran Cormorant or, more rarely, as the Socotra Shag. Individuals occasionally migrate as far west as the Red Sea coast. Despite its name, it was only confirmed in 2005 that it breeds on Socotra.
The Socotra Cormorant is an almost entirely blackish bird with a total length of about 80 centimetres (31 in). In breeding condition, its forecrown has a purplish gloss and its upperparts have a slaty-green tinge, there are a few white plumes around the eye and neck and a few white streaks at the rump. Its legs and feet are black and its gular skin blackish. All these deviations from pure black are less marked outside the breeding season.
There is little information on this species' foraging or diet. Like all cormorants its dives for its food. Older reports suggest that it can stay submerged for up to 3 minutes, which is high for a cormorant and suggests that it would be capable of deep diving. However there are also reports of forgaging in flocks, and this is more usually seen in cormorants that feed in mid water.
The birds are highly gregarious, with roosting flocks of 250,000 having been reported, and flocks of up to 25,000 at sea.
Since 2000, this species has been listed as Vulnerable on the IUCN Red List, on the grounds of its small number of breeding localities and ongoing rapid decline. The decline is caused by coastal development, disturbance and marine pollution near its nesting colonies; in 2000 it was estimated that the world population was about 110,000 breeding pairs or 330,000–500,000 individual birds. The only protected nesting colony in the Persian Gulf is one of about 30,000 pairs on the Bahraini Hawar Islands off the coast of Qatar, and this is a Ramsar Convention listed site. Of the remaining 13 colonies (9 different locations), the Hawar colony is the largest. In the northern part of its range alone, about 12 colonies are known to have disappeared since the 1960s. The birds may also be affected by oil pollution at sea. During the First Gulf War images of badly oiled cormorants from the Gulf were regularly shown in the western media, and although the Great Cormorant is also found in the Gulf, it is likely that many of these were Socotra cormorants.
The Socotra Cormorant is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies.
- BirdLife International (2012). "Phalacrocorax nigrogularis". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
- Mughal, Muhammad Aurang Zeb. 2013. Persian Gulf Desert and Semi-desert. Robert Warren Howarth (ed.), Biomes & Ecosystems. Ipswich, MA: Salem Press, pp. 34-36.
- BirdLife International (2011). Species Factsheet: Phalacrocorax nigrogularis. Retrieved 5 October 2011.
- Bahrain Bird Report. Socotra Cormorant. Retrieved 5 October 2011.
- Johnsgard, P. A. (1993). Cormorants, darters, and pelicans of the world. Washington DC: Smithsonian Institution Press. ISBN 1-56098-216-0
- A large gallery of images of Socotra cormorants on the "Birds Oman" website