Nesting conservation priorities by geographic scale: preliminary lessons from the application of percent thresholds to the identification of Key Biodiversity Areas for Marine Turtles in Melanesia

摘要

The Key Biodiversity Area (KBA) approach was initially developed for terrestrial species, and is appropriate for the conservation and management of species that require conservation at the site scale (Eken et al., 2004). We can infer from Langhammer et al. (2007) that the identification of KBAs is relatively straightforward for species listed on the IUCN Red List of Threatened Species as Critically Endangered (CR) or Endangered (EN) and also have highly restricted global ranges; this remains true even in situations of data scarcity. Alliance for Zero Extinction (AZE) trigger species provide a perfect example, being CR or EN species which are restricted to a single site worldwide (Ricketts et al., 2005; www.zeroextinction.org). Marine turtles are wide-ranging and highly migratory, but nevertheless have site-specific conservation needs based on seasonal congregatory behavior; they clearly present a challenging example for applying the KBA approach. Testing the applicability of the KBA approach to such wide-ranging species and devising appropriate thresholds for site identification were the fundamental challenges that we faced in our analysis. Our findings highlighted the importance of scale and context in determining appropriate population thresholds for site identification for globally ranging species such as marine turtles.