Organochlorine Residues in Adults of Six Southwestern Bat Species

Abstract

Fifty adult bats collected in Arizona [USA] and Sonora, Mexico, including long-nosed (Leptonycteris sanborni), leaf-nosed (Macrotus waterhousii), pallid (Antrozous pallidus), big brown (Eptesicus fuscus), western pipistrelle (Pipistrellus hesperus) and Mexican free-tailed bats (Tadarida brasiliensis), were analyzed for organochlorine residues. All contained DDE (range, 0.1-160 ppm; median, 4.3 pp. wet weight basis) and DDT (range, < 0.1-550 ppm; median, 0.2 ppm). DDD was found in 38 bats, dieldrin in 16, o,p''-DDT (at 33-220 ppm) in 3, toxaphene in 3, Aroclor 1254 in 1, and Aroclor 1260 in 1. Bats with the highest residue levels were collected in or near human dwellings. The 5 herbivorous long-nosed bats averaged only 0.51 ppm DDT and metabolites, whereas the others, all insectivores, averaged 46 ppm.