Microhabitat partitioning among small passerines in a Pacific island bird community
Craig RJ and Beal KG. 2002. Microhabitat partitioning among small passerines in a Pacific island bird community. Bird Conservation Research, Inc.. :1-12
"We report on continuing studies of the small forest passerines of Saipan, Mariana Islands, Micronesia, in order to (1) characterize the ecological strategies employed in this threatened but virtually unstudied bird assemblage, and (2) provide a baseline for assessing shifts in foraging and mircohabitat use that might follow reestablishment of extirpated populations. Data were gathered on microhabitat selection and foraging behavior, and limited observations are reported on wet-dry season shifts and annual changes in foraging. Two species were primarily canopy species, with one (Bridled White-eye, Zosterops conspicillatus) a live-leaf gleaner using smaller perches of taller trees, particularly Cynometra ramiflora, and one (Micronesian Honeyeater, Myzomela rubratra) a flower prober using larger perches of taller trees. The remaining two occupied the canopy and understory, with one (Rufous Fantail, Rhipidura rufifrons) an aerial forager and one (Golden White-eye, Cleptornis marchei) a more generalized forager that selected larger perches of a wider variety of smaller trees. Hence, the species ecologically overlap, but are differentiated in use of microhabitat space, including both structural and floristic components, and in manner of foraging. Comparisons of ecological overlap demonstrated that the two white-eye species were the most similar of the four, and that the Rufous Fantail and Mirconesian Honeyeater were most dissimilar. Each of the four species also exhibited versatility in their ability to exploit the forest habitat. Such versatility is advantageous in a periodically typhoon-ravaged system, although competitive release could have contributed to this versatility. Prior to reestablishemnt of prehistorically extinct populations, additional studies should address the degree to which species interactions might influence the outcomes of such efforts."
- Type
- Journal Article
- Authors
- Craig, Robert; Beal, Kathleen
- Units
- AMME , PACN
- Keywords
- Animal Studies, Bridled white-eye, Foraging Behavior, Golden white-eye, Habitat Selection, Micronesian honeyeater, Rufous fantail, Saipan, small passerines