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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Reproductive success and nesting periodicity of a pair of African Crowned Eagles breeding in KwaZulu-Natal

Malan, G January 2005 (has links)
The African Crowned Eagle, Stephanoaetus coronatus, is a large raptor with a particularly long breeding cycle, even considering its size (Newton 1979). The incubation period is 49–51 days, the nestling period is 104–115 days and the length of the post-fledging period is contentious and varies considerably within its distribution in Africa (Steyn 1982). In some regions where the bird breeds biennially, this period is up to 350 days (Brown and Amadon 1989, Shultz 2002), whereas in other regions the post-fledging period is shorter as pairs bred annually, even for nine years in succession (Vernon 1984). The reason for this discrepancy has been ascribed to environmental quality and seasonal variability, and differences in the main prey base, densities and mortalities between populations (Newton 1979, Jarvis et al. 1980, Steyn 1982, Vernon 1984, Boshoff et al. 1994, Shultz 2002). Furthermore, it is unclear if the fledglings disperse from the nesting area of their own free will or are evicted by the parents (Brown 1966, Oatley 1970).

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