Ascension : Conservation Weekly Submitted by The Islander (Gary Robinson) 03.08.2006 (Article Archived on 17.08.2006)
The Ascension Frigate Bird - Prepared by Natasha Williams
The Ascension Frigate bird is unique, breeding only on Ascension Island. It once occurred in huge numbers on the main island but rapidly declined because of hunting by sailors and colonists and predation by introduced rats and cats. Today the species nests only on the summit of isolated Boatswain Bird Island.
An estimated 6,000 pairs of this endemic bird are found on Ascension as stated before they all nest on Boatswain Bird Island. They can be seen at Long beach. They feed mainly on fish, which they pick from the sea surface. All prey is taken in flight, as frigate birds cannot normally take off from water. Frigate birds also pursue other seabird species and force them to drop their cat. They take turtle hatchlings and raid sooty tern colonies for unguarded chicks. They disperse widely when not breeding.
Nesting
The Ascension Frigate breeds through out the year but nesting activity peaks around October-November time. During courtship males inflate their throat sacs and vibrate their wings to attract females flying ahead. The Male Frigate is black with a red throat pouch and the females are black, but have a dark brown collar and breastband. Juveniles have white heads. The nest is a simple platform of vegetable matter and other debris usually among rocks on flat areas or broad cliff ledges. The single white egg is unusually small for the size of the bird, its 45 day incubation being shared by both parents. The chick, although fledged when six months old, is dependent on its parents for most of its first year. This means that frigate birds can only nest in alternate years
 
Adult female frigatebird with chicks on BBI Adult male frigatebird displaying on BBI
Photos by Anselmo Pelembe
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