Hierarchical distance sampling reveals increased population size and broader habitat use in the endangered Bahama Oriole

Avian Conservation and Ecology

article

Michael G. Rowley¹  Richard C. Stanley²  Janine M. Antalffy¹  Jennifer L. Christhilf³  Daniel C. Stonko¹  Scott B. Johnson⁴  Shelley Cant-Woodside⁴  T Scott Sillett⁵  Matthew E. Fagan³  Colin E. Studds³  Kevin E. Omland¹ 

[1] University of Maryland, Baltimore County ,(UMBC), Biological Sciences;University of Florida, School of Natural Resources and Environment;University of Maryland, Baltimore County ,(UMBC), Geography and Environmental Systems;Bahamas National Trust;Smithsonian Conservation Biology Institute

关键词: Bahama Oriole;    Caribbean;    endangered species;    island endemic;    hierarchical distance sampling;    Icterus northropi;   

DOI  :  10.5751/ACE-01775-160105

学科分类：口腔科学

来源: Resilience Alliance Publications

【 摘 要 】

The Caribbean is home to over 20 passerine species listed by the International Union for Conservation of Nature as vulnerable, endangered or critically endangered. The Bahama Oriole (Icterus northropi) is listed as critically endangered and is now restricted to Andros, a single island complex in The Bahamas. We investigated this species' habitat use and produced the first statistically robust estimate of population size. We conducted point counts during the Bahama Oriole's breeding season in May and June 2017, extensively surveying the northern part of North Andros over a study area covering 713 km². Hierarchical distance sampling models estimated 1269–2765 individuals within our study area, a substantially larger population on North Andros than was indicated by the previously published estimates. Earlier studies, which disproportionately sampled anthropogenic and coppice habitats, likely underestimated this species' abundance in pine forest. We found that the Bahama Oriole is widespread, most abundant in pine forest, and not dependent on developed habitats during the breeding season. These findings provide a better outlook for the species' persistence and indicate that conserving pine forest would benefit this critically endangered species. Our results also emphasize the importance of rigorously evaluating habitat use when developing conservation plans for endangered species. Systematic population counts and statistical analyses that account for detection probability are needed for endangered and vulnerable endemic birds across the Caribbean, especially in the face of increased hurricane strength and sea level rise due to climate change.

【 授权许可】

CC BY