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Multiple-brooding in birds of prey: South African Black Sparrowhawks Accipiter melanoleucus extend the boundariesCurtis, O, Malan, G, Jenkis, AR, Myburgh, N 10 January 2005 (has links)
Multiple-brooding (raising more than one brood of young in quick succession) occurs infrequently
in raptors and is generally restricted to either smaller species with shorter nesting
periods, co-operative breeders or species capable of capitalizing on conditions of prolonged food
abundance whenever they occur. This paper presents the first recorded cases of multiplebrooding
in the Black Sparrowhawk Accipiter melanoleucus from two distinct locales in
South Africa. In the Western Cape (Cape Peninsula), four attempts to multiple-brood were
recorded in four different years, involving three distinct pairs of birds, and in KwaZulu–Natal
(Eshowe), three distinct pairs of Sparrowhawks successfully multiple-brooded on several
occasions over a 5-year study period. These results establish the Black Sparrowhawk as one
of only two relatively large, monogamous raptor species, and the only specialist bird-eating
raptor, in which multiple-brooding has been recorded with any frequency. The species’
capacity to thrive in human-modified environments (i.e. alien plantations) and particularly
to exploit associated foraging opportunities (e.g. high densities of doves and pigeons in suburban
areas) may, at least partly, account for the instances of multiple-brooding reported
here. We suggest that biologists be more vigilant for cases of multiple-brooding in raptors,
as it is possible that this trait is more common than originally thought and has previously
been overlooked.
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