Aspects of the Life History and Foraging Ecology of the Endangered Akiapolaau

Publication Type:Journal Article
Year of Publication:1996
Authors:C. Ralph, J, Fancy, SG
Journal:The Condor
Date Published:1996
ISBN Number:00105422
Keywords:Fringillidae, Hemignathus, Hemignathus munroi, Hemignathus wilsoni, Heterorhynchus, Heterorhynchus wilsoni
Abstract:Relative abundance, breeding ecology, annual survival, home range, and foraging ecology of Akiapolaau (Hemignathus munroi), an endangered Hawaiian honeycreeper, were studied on the island of Hawaii. The species is a specialist: Akiapolaau used koa (Acacia koa) for foraging much more than expected based on koa availability, and most Akiapolaau occurred in old-growth koa and ohia (Metrosideros polymorpha) forests. Male Akiapolaau most often foraged on the trunks and large branches of koa, whereas females used small branches and twigs. The longer bill of males is apparently adapted to the greater bark thickness of larger branches. Lichen-covered and dead branches were preferred feeding sites. Akiapolaau showed serial monogamy and had a relatively low reproductive rate of 0.86 young pair-1 year-1, with a long parental dependency period. Home range sizes averaged 10.7 ha and did not differ between males and females. Annual survival for adults was 0.71. Avian diseases appear to restrict Akiapolaau to higher elevation forests where mosquitos are rare. Protection of remaining old-growth koa and ohia forests above the mosquito zone are critical to the survival of the species.
Short Title:The Condor
Taxonomic name: 
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