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USGS · 70024237

Home range and territoriality of two Hawaiian honeycreepers, the 'Akohekohe and Maui Parrotbill

Thane K. Pratt·John C. Simon·Brian P. Farm·Kim E. Berlin·James R. Kowalsky
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Abstract

Hawaiian honeycreepers have radiated into a diversity of trophic niches and patterns of space-use. We investigated space-use in two honeycreeper species, the ‘Ākohekohe ( Palmeria dolei ), an endangered nectarivore, and Maui Parrotbill ( Pseudonestor xanthophrys ), an endangered wood excavator, by mapping the home ranges and dispersion of color-banded individuals at a study site in relatively undisturbed montane cloud forest on Maui Island, Hawai‘i. With 20% of outlying points excluded, home-range size averaged much smaller for adult male ‘Ākohekohe (0.56 ha) than for male Maui Parrotbill (2.26 ha). In both species, a female's home range mostly overlapped that of her mate. Adult male Maui Parrotbill defended year-round home ranges from which they excluded conspecifics except for their mates and dependent offspring. Although our data suggest that ‘Ākohekohe also maintained all-purpose territories, the evidence is less convincing because these birds were seen feeding in the home ranges of other individuals. By defending all-purpose territories, these two species depart from the more common honeycreeper pattern of sharing large, undefended home ranges.

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Thane K. Pratt, John C. Simon, Brian P. Farm, Kim E. Berlin, James R. Kowalsky. 2001. Home range and territoriality of two Hawaiian honeycreepers, the 'Akohekohe and Maui Parrotbill. https://doi.org/10.1650/0010-5422(2001)103%5B0746%3Ahratot%5D2.0.co%3B2

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