Nest success and parental investment in the Critically Endangered Maui parrotbill Pseudonestor xanthophrys with implications for recovery

[摘要] ABSTRACT: The Critically Endangered (IUCN) Maui parrotbill Pseudonestor xanthophrys, an endemic Hawaiian honeycreeper, is restricted to a single population of about 500 individuals. During 3 breeding seasons (2006 to 2008) we found and monitored 17 Maui parrotbill nests from 13 pairs. Eggs and incubating females were confirmed for 12 of the nests, but only 4 fledged successfully. Severe weather led to nest abandonment in 5 cases. Two nests were depredated, and 1 nest had an egg that failed to hatch. Three pairs renested after failures. We used logistic linear regression and ANOVA to evaluate 300 h of observations to assess the effects of parental investment behavior and weather on nest fate. Female time incubating, a significant factor explaining nest fate, did not differ by time of day, but averaged 12 min h^–1 less for failed than for successful nests. Male provisioning rates to adult females and chick feeding rates by parents were also significantly related to nest success. Male vocalizations near the nest did not differ by nest fate. Establishment of a second population is a key step in the recovery of Maui parrotbills, and a small captive population has been established. Although limited, our data suggest that collection of Maui parrotbill eggs and/or nestlings up to 1 wk old from nests for captive rearing, especially in advance of severe winter storms, would have minimal effects on the population.

[学科分类] 动物科学

[关键词] Maui parrotbill;Avian ecology;Parental investment;Endangered birds