Author: Congdon, B. C., Preker, M.
Year: 2004
Title: Sex specific chick provisionning and kleptoparasitism in the least Frigate bird, Fregata ariel.
Journal: Emu
Volume: 104
Pages: 347-351
Keywords: Fregata ariel; sex specific; kleptoparasitism

Abstract: We examined sex-specific patterns of provisionning behaviour  and kleptoparasitic host-use in the Least Frigatebird Fregata ariel. We aimed to determine, first, wheter sex-specific kleptoparasitism, either at sea, or adjacent to the breeding colony, is an important source of food for chick provisionning and, second, whether observed behaviour is consistent with the expectation that sexual size-dimorphis in resource-poor environments consistently results in sexa-specific divergence of foraging behaviour. We observed sex-specific differences in the time of day that adult frigatebirds provision chicks but no differences in the overall provisionning rate between sexes. We laso observed no sex-specific kleptoparasitism via simultaneous monitoring of prosioning by Least Frigatebirds and Masked Boobies. Sex-specific differences in prey types attacked at the colony were observed, but these conflicted with predictions based on previous studies and were directly correlated with diural patterns of adult frigatebird attendance. Overall, we suggest that sexual differences in foraging behaviour in Least Frigatebirds are minimal and relate to either the use of different risk-sensitive foraging strategies by each sex, or are a consequence of body ssize differences in independently foraging sexes. While our results must be considered preliminary, we believe they provide justification for further critical examination of mechanisms of sex-specific behavioural divergence in seabird taxa.