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On the Bateleur, especially at the Nest
Author(s) -
Moreau R. E.
Publication year - 1945
Publication title -
ibis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.933
H-Index - 80
eISSN - 1474-919X
pISSN - 0019-1019
DOI - 10.1111/j.1474-919x.1945.tb02991.x
Subject(s) - fledge , carrion , nest (protein structural motif) , geography , white (mutation) , predation , demography , breed , ecology , biology , zoology , biochemistry , sociology , gene
Summary An account is given of one hundred hours of observations at a Bateleur'a nest in north‐eastern Tanganyike Territory. The adults were a white‐backed bird and a chestnut‐backed, with a sub‐adult; probably over three years old, in association with them. The youngster took 130 dap to fledge. During at least part of the time all its food was brought by the white‐backed adult. When the fledgling was about one month old its feeds averaged about one in eight hours; during its last week in the nest feeds were nearly three times as frequent. Literature and unpublished data are reviewed in relation to special points of interest, viz.:— Slow development and maturation accords with longevity. Fledging period apparently longer than authentically recorded for any land bird. First wing‐moult may have started before first flight. Tail length is greater in proportion to wing in juveniles than in adults. Proportion of white‐becks to chestnut‐backs differs in parts of Africa, being least in South africa. White‐tailed birds seem confined to Sudanese semi‐desert belt. Voice, flight habits and wing‐noises seem to differ in parts of Africa. Food comprises both carrion and live prey, especially snakes, but not poultry or other birds. Claws are not less sharp than those of Stephanoaëtus and Polemaëtus . Breeding records in Tropical Africa show, when analysed with reference to egg‐dates, that as a rule in each area the young get through their fledging period, or at least the later, unbrooded part, during the local cool dry season. Psychologically the Bateleur is most peculiar: in the wild it is shy of man, sociable with big birdv of its own and other species, and breeding birds tolerate sub‐adults: in captivity it becomes unusually tame, has a grecting ceremony for friends and likes to be handled.