This is a very common and widespread bird
species. It feeds on the sea, in estuaries, and on freshwater lakes and rivers.
Northern birds migrate south and winter along any coast that is well-supplied
with fish. In Malaysia it is a rarity but there are sighting in coastal waters
until Selat Tebrau Johor off Singapore side as recent as this year 2010.The Great Cormorant is a large black bird, but there is a wide variation in size in the species wide range. Weight is reported from 1.5 kg (3.3 lbs)[1] to 5.3 kg (11.7 lbs)[2], with a typical range from 2.6 to 3.7 kg (5.7-8.2 lbs).. Length can vary from 70 to 102 cm (28–40 in) and wingspan from 121 to 160 cm (48–63 in). It has a longish tail and yellow throat-patch. Adults have white thigh patches in the breeding season.
The Great Cormorant can dive to considerable depths, but often feeds in shallow water. It frequently brings prey to the surface. A wide variety of fish are taken: cormorants are often noticed eating eels, but this may reflect the considerable time taken to subdue an eel and position it for swallowing, rather than any dominance of eels in the diet. In British waters, dive times of 20–30 seconds are common, with a recovery time on the surface around a third of the dive time. The Great Cormorant is one of the few birds which can move its eyes, which assists in hunting.
Cormorant fishing is practiced in China, Japan, and elsewhere around the globe. In it, fishermen tie a line around the throats of cormorants, tight enough to prevent swallowing, and deploy them from small boats. The cormorants catch fish without being able to fully swallow them, and the fishermen are able to retrieve the fish simply by forcing open the cormorants' mouths, apparently engaging the regurgitation reflex.
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