Noteworthy Records of the Eastern Pipistrelle, Perimyotis Subflavus, And Silver-Haired Bat, Lasionycteris Noctivagans, (Chiroptera: Vespertilionidae) from the Chisos Mountains, Texas‪.‬

Twenty species of bats have been documented from Big Bend National Park (Easterla 1973; Higginbotham et al. 1999; Higginbotham & Ammerman 2002), however the occurrence of one of these, Lasiurus borealis, has been questioned (Easterla 1975). Most netting efforts have been conducted at the lower elevations in the park, but a few investigators have examined the bat species occurring in the Chisos Mountains (Borell & Bryant 1942; Easterla 1973). The Chisos Mountains, within Big Bend National Park (BBNP), range up to 7835 ft (2388m) elevation at the highest peak. The vegetation is dominated by a woodland plant association (pinyon/juniper/oak), however some moist canyons support a cypress/pine/oak association (Wauer 1971). This report documents the occurrence of Perimyotis (Pipistrellus) subflavus and Lasionycteris noctivagans in a moist woodland canyon of the Chisos Mountains (Brewster County, Texas) and brings the total diversity of bats in Big Bend National Park to 22 species--one of the highest for any national park. One adult male eastern pipistrelle, Perimyotis subflavus, and two adult male silver-haired bats, Lasionycteris noctivagans, were collected by mistnet on 22 May 2004. Use of the genus Perimyotis instead of Pipistrellus follows the recommendation of Menu (1984) and Hoofer & Van Den Bussche (2003). Both species were collected at 2097m (6880 ft) elevation over pools in Boot Spring drainage (UTM 13R 0665488E 3235919N) in the Chisos Mountains. These three individuals were the first captured that evening (between 2110 and 2130h). Specimens were deposited in the Angelo State Natural History Collection (Perimyotis subflavus, ASNHC 12899; Lasionycteris noctivagans, ASNHC 12897 and 12898) and tissues were deposited in the Angelo State Natural History Frozen Tissue Collection (P. subflavus, ASK 6764; L. noctivagans ASK6765, 6766). According to Schmidly (2004) these species are uncommon in the Trans-Pecos and have not been documented in BBNP or Brewster County, Texas. Therefore, these specimens represent new records for Brewster County.