Ascension : Conservation Weekly
Submitted by The Islander (Raymond Ellick) 21.09.2006 (Article Archived on 05.10.2006)
Sooty Terns which are known as Wideawakes, they come to Ascension during their nesting cycle that’s about 9.6 months and they start by pairing up
Prepared by Natasha Williams-Conservation Assistant
Sooty Terns
Sooty Terns which are known as Wideawakes, they come to Ascension during their nesting cycle that’s about 9.6 months and they start by pairing up, this is called nightclubbing, and then once the adults are paired up the females sits itself on a patch on the rocks while the males bring and fetch food for the female, because the Sooty Tern can only produce one egg, the egg is about a 5th of the females body weight therefore she will require a large amount of food. They eat small flying fish which is the most important prey of Sooty Terns and seasonal changes in their diet can have a strong bearing on the birds’ nesting patterns. At Ascension, the water is always warm enough to support large numbers of flying fish; therefore the Sooty Terns here can breed more efficiently.
At St Helena the Sooty Terns, however, conditions are favourable for part of the year and its Sooty Terns, consequently, have a 12 month nesting cycle.
St Helena’s rarest seabird. The species fares badly when its breeding sites become accessible to predatory mammals. Even on Ascension, when terns still breed on traditional ‘fairs’ on the lava plains, their numbers have been seriously reduced by cats and rats. It is estimated that half a million pairs of Sooty Terns nested on Ascension in the 1950s. Less than half that number breeds here to day. The danger from introduced mammals has resulted in seabirds being forced into predator-free stacks.
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