Reassessing the Conservation Status of an Island Endemic Frog

Abstract

Abstract Amphibians are among the most endangered organisms on Earth; however, few monitoring studies have been conducted in the tropics despite high amphibian diversity in these regions. To help fill this gap, we completed fieldwork to reassess the status of the Bloody Bay Poison Frog (Mannophryne olmonae, an endemic from the island of Tobago), classified as “Critically Endangered” by the original IUCN Global Amphibian Assessment, though recently downgraded to “Vulnerable.” To assess occupancy patterns and population stability, we used occupancy modeling with three years of listening survey data (2011–2013) from 35 sites. To examine patterns of relative abundance and recruitment, we gathered frog encounter rate and body size data from 18 stream-side transects. To assess current distributional limits, we conducted listening surveys at and beyond the known range limits. Together, these data suggest that M. olmonae is more widely distributed than previously reported (we found 23 extralimital populations), i...