Distribution, abundance and conservation of the highly endemic Coral Pink Sand Dunes tiger beetle, Cicindela albissima Rumpp

Abstract

The Coral Pink Sand Dunes tiger beetle, Cicindela albissima Rumpp, occurs only within a small area of the Coral Pink Sand Dunes in southwestern Utah. Even within this dune field, most of the population is limited to a small core area about 2 × 0.5 km2 in size (adjacent areas sometimes contain beetles, but these appear to be demographic sinks). The core habitat is a transition zone of transverse dunes located between more dynamic dunes to the south (crests of these move upwards of 3 m/y) and more stabilised ones to the north. A candidate species since 1994, the beetle was recently proposed for listing as a threatened species by the US Fish and Wildlife Service. A conservation agreement in 1997 established two off-highway-vehicle-free conservation areas, one of these supporting most of the population within the core habitat (A) and the other a potential site for establishing a second viable population (B). Annual population estimates of adults from 1999 to 2013 fluctuated significantly from a low of 558 to high of 2944. Despite a progressive increase in recent years, our studies including two population viability analyses confirmed the species remains at risk of extinction because of its localised distribution, fluctuating abundance apparently limited by reduced rainfall and the failure to establish a second population in Conservation Area B. The fate of the species is tied to the five inter-dunal swale rows that support most of the adults and larvae. Consequently, there are few options for conservation of the species. Proposed listing of C. albissima as a threatened species was recently withdrawn by the US Fish and Wildlife Service in lieu of a revised conservation agreement which modestly expands protection in Conservation Area A.