PARENT SESSION
Oral Session # 58: Rare, Threatened, and Endangered Species III: Reptiles and Amphibians.
Presiding: K Beard
Wednesday, August 6. 1:30 PM to 5:00 PM, SITCC Meeting Room 202.
Estimating site occupancy and detection probabilities for terrestrial salamanders.
Bailey, Larissa *,1, Simons, Theodore1, Pollock, Kenneth 2, 1 North Carolina State University, Raleigh, NC, USA2 North Carolina State University, Raleigh, NC, USA
ABSTRACT- World-wide concern for amphibian populations has focused research on documenting amphibian distributions and habitat associations over large geographic areas. Most programs involve sampling potential habitats using a wide variety of techniques to document species occurrence and relative abundance. Population declines may be inferred by a decrease in the number of sites win which a species is detected. These methods assume constant (often perfect) species detectability over time, space, and among different sampling methods. We utilized recent developments in capture-recapture theory to estimate proportion of sites occupied and species detection probabilities for a suite of salamanders found in Great Smoky Mountains National Park. We included large-scale habitat characteristics (e.g. elevation, vegetation type, and stream presence) as site and sampling covariates. We explored differences among area-constrained and coverboard sampling techniques. We found species-specific differences in detection probability ranging from 0.26-0.72. Detection probabilities were lower for coverboards than area-constrained searches for all terrestrial species. Habitat characteristics were important in both site occupancy and detection probabilities but varied among species. Nevertheless, the identification of important habitat characteristics was consistent among sampling methods. We strongly recommend incorporating detectability estimation into research studies designed to document presence and spatial distribution of amphibian species.
Key words: monitoring, site-occupancy, salamanders