The Nevada Test Site (NTS) is located in south-central Nevada and encompasses approximately 3,561 square kilometers. It straddles both the Mojave and Great Basin Deserts and includes a distinct transition region between these two deserts. Because of its size and geographical location, a great deal of vegetative and physiographic diversity exists on the NTS. This diversity of habitat allows for a diverse mix of bat species to exist on the NTS. Numerous mines and tunnels occur on the NTS, which are potential roost sites for bats. Several man-made and natural water sources also occur throughout the NTS. Multiple techniques have been used to inventory and monitor the bat fauna on the NTS. These techniques have included mistnetting at water sources with and without concurrent acoustic sampling, acoustic road surveys, and acoustic sampling at mine and tunnel entrances. To date, a total of 14 species of bats has been documented on the NTS, of which seven are considered species of concern by the U.S. Fish and Wildlife Service. These include Townsend's big-eared bat (Corynorhinus townsendii), spotted bat (Euderma maculatum), small-footed myotis (Myotis ciliolabrum), long-eared myotis (M. evotis), fringed myotis (M. thysanodes), long-legged myotis (M. volans), and big free-tailed bat (Nyctinomops macrotis). The Townsend's big-eared bat, spotted bat, long-eared myotis, and big free-tailed bat have been found exclusively in the Great Basin Desert ecoregion, and bat species richness was highest in this region based on mistnet and acoustic surveys. The small-footed and long-legged myotis were found throughout the NTS, and the fringed myotisms found in the Mojave and Great Basin Desert ecoregion but is likely to be found in the transition ecoregion as well. The small-footed myotis, long-legged myotis, and western pipistrelle were the most frequently detected species in the Great Basin Desert ecoregion. The western pipistrelle and California myotis were the most detected species in the transition ecoregion, while the western pipistrelle, California myotis, and pallid bat were the most frequently detected species in the Mojave Desert ecoregion. Acoustic sampling using the Anabat II system has greatly facilitated the monitoring of bats on the NTS, and allowed biologists to cost-effectively survey large areas for bat activity.
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