Birds of Srilanka (Part 2)

Pelicans


A pelican, derived from the Greek word pelekys (meaning “axe” and applied to birds that cut wood with their bills or beaks) is a large water bird with a large throat pouch, belonging to the bird family Pelecanidae.


Pelicans are large birds with large pouched bills. The smallest is the Brown Pelican, small individuals of which can be as little as 2.75 kg (6 lb), 106 cm (42 in) long and can have a wingspan of as little as 1.83 m (6 ft). The largest is believed to be the Dalmatian Pelican, at up to 15 kg (33 lb), 183 cm (72 in) long, with a maximum wingspan of 3 meters. The Australian Pelican has the longest bill of any bird.


Pelicans swim well with their short, strong legs and their feet with all four toes webbed (as in all birds placed in the order Pelecaniformes). The tail is short and square, with 20 to 24 feathers. The wings are long and have the unusually large number of 30 to 35 secondary flight feathers. A layer of special fibers deep in the breast muscles can hold the wings rigidly horizontal for gliding and soaring. Thus they can exploit thermals to commute over 150 km (100 miles) to feeding areas.




The diet of a Pelican usually consists of fish, but they also eat amphibians, crustaceans and on some occasions, smaller birds. They often catch fish by expanding the throat pouch. Then they must drain the pouch above the surface before they can swallow. This operation takes up to a minute, during which time other seabirds are particularly likely to steal the fish. Pelicans in their turn sometimes pirate prey from other seabirds.


The Dalmatian Pelican and the Spot-billed Pelican are the rarest species, with the population of the former estimated at between 10,000 and 20,000 and that of the latter at 13,000 to 18,000. The most common is believed to be the Australian Pelican, with a population generally estimated at around 400,000 individuals. However, estimates for the species have varied wildly between 100,000 and 1,000,000 over the years, and it is possible that the White Pelican, the population of which is more consistently estimated at 270,000 and 290,000 individuals, is in fact the more common species. The brown pelican may be even more numerous with estimates of 650,000 birds throughout its range. It has been removed from the endangered species list.