Comparative aspects of the Ecology of the Bulbus of Coastal Tanzania

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University of Dar es Salaam
Ten bulbul species occurring in coastal Tanzania were studied from January 1989 to June 1990. The annual cycles of breeding and moulting,and possible mechanisms of interspecific ecological isolation are described. Both breeding and moulting are seasonal events; the former occurs between October and June and primary moult takes place mostly from January to September -Despite the temporal separation in their onset and cessation, periodicities of the two physiological events greatly overlap. It is suggested that the seasonality of these events are correlated to changes in the annual cycle of climatic factors which influence availability of food supply. The extended period of breeding-moult overlap could be a strategy to maximize utilization of food during the period of increased supply, and to minimize the energetic cost of moulting. Almost all species showed marked individual Variability in the onset of primary moult in some this was due to the sexes differing in the time at which moult was initiated. It is suggested that a possible reason for this difference in time of initiation of moult is related to the degree of participation in rearing of the studied are also compared with similar studies elsewhere in the Afrotropical region.With regard to the sympatric occurrence of bulbuls, habitat and feeding differences are proposed as the two most important means of ecological segregation. Interspecific differences in body mass and morphological characters have been presumed to reflect feeding quantity of food, and/or foraging methods. The conservation applicability of ringing, a non-destructive sampling method in bird studies is emphasized, and areas for further study are suggested.
Available in print form, East Africana Collection, Dr.Wirbert Chagula Library, Class mark (THS EAF QL696.P268M5)
Bulbuls, Zoology, Ecology
Mlingwa, Charles. O. F (1991) Comparative aspects of the Ecology of the Bulbus of Coastal Tanzania, Masters dissertation, University of Dar es Salaam, Dar es Salaam.