POPULATION STATUS OF THE ENDANGERED LAYSAN FINCH

The Laysan Finch (Telespiza cantans) is an endangered Hawaiian honeycreeper that occurs on only a few small islands in the northwestern Hawaiian Island Archipelago. Twenty-two years of recent population estimates (1991 2012) from Laysan Island were analyzed to ascertain the current status of this endangered species; the entire 44 years of census data available were then used to identify long-term population trends. Laysan Finch population estimates have exhibited extreme fluctuations that can be attributed at least in part to spring rainfall patterns. The average population size has remained at similar to 10,000 individuals. The Poisson regression analysis conducted for the last 22 years indicates a slightly deceasing annual population trend. However, when all 44 years of data were included in a comprehensive trend analysis, a stable population trend was documented. These results highlight the importance of long-term data sets when monitoring small closed populations a situation commonly encountered with endangered species. Inherent resilience has allowed the finch population to rebound from declines and fluctuate around Laysan Island's carrying capacity, but the future is uncertain as climate change is expected to impact its low island habitats. Received 17 October 2011. Accepted 27 August 2012.