O’SHEA, CRYAN & BOGAN: UNITED STATES BAT SPECIES OF CONCERN 
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was one of the 14 taxa of mammals placed on the original U.S. endangered species list in 1967 
(Udall, 1967). Other species of bats were subsequently added to this list, and by 1994 increasing 
concern for the status of bat populations was reflected in the designation of 24 species or sub¬ 
species of bats among a broader group of animals considered to be Category 2 candidates for fed¬ 
eral listing under the U.S. Endangered Species Act of 1973 (U.S. Fish and Wildlife Service, 1994; 
Table 1). Category 2 candidates were defined as “taxa for which information...indicates that pro¬ 
posing to list as endangered or threatened is possibly appropriate, but for which persuasive data on 
biological vulnerability and threat are not currently available to support proposed rules” (U.S. Fish 
and Wildlife Service, 1994:58983). 
Species of Concern 
Category 2 candidate species were not provided any official protection, and in 1996 the U.S. 
Fish and Wildlife Service discontinued the use of a Category 2 candidate status for all such previ¬ 
ously designated animals and plants. Instead they noted “the Service remains concerned about 
Table 1. Species or subspecies of bats in the U.S. and territories originally designated as Category 2 can¬ 
didates for listing under the Endangered Species Act in 1994 (U.S. Fish and Wildlife Service, 1994). In 1996, 
the U.S. Fish and Wildlife Service eliminated Category 2 but considered all species of plants and animals for¬ 
merly categorized as such to be “species of concern” (U.S. Fish and Wildlife Service, 1996a, 1996b). CNMI 
= Commonwealth of the Northern Mariana Islands. Bat names have been updated. 
Species or Subspecies of Bat 
General Distribution in United States 
Choeronycteris mexicana, Mexican long-tongued bat 
Arizona, New Mexico 
Corynorhinus rafinesquii, Rafinesque’s big-eared bat 
Southeastern and south-central U.S. 
Corynorhinus townsendii pallescens, Pale Townsend’s big-eared bat 
Western U.S. (inland populations) 
Corynorhinus townsendii townsendii. Pacific Townsend’s big-eared bat 
Western U.S. coast 
Emballonura semicaudata, Pacific sheath-tailed bat 
Pacific islands (several island groups) 
Euderma maculatum. Spotted bat 
Western U.S. 
Eumops perotis californicus, Greater bonneted bat 
West coast and southwestern U.S. 
Eumops underwoodi, Underwood’s bonneted bat 
Arizona 
Idionycteris phyllotis, Allen’s big-eared bat 
Southwestern U.S. 
Macrotus californicus, California leaf-nosed bat 
Southwestern U.S. 
Myotis austroriparius, Southeastern myotis 
Southeastern and south-central U.S. 
Myotis ciliolabrum. Western small-footed myotis 
Western U.S. 
Myotis evotis. Long-eared myotis 
Western U.S. 
Myotis leibii. Eastern small-footed myotis 
Central and eastern U.S. 
Myotis occultus, Arizona myotis 
Southwestern U.S. 
Myotis thysanodes. Fringed myotis 
Western U.S. 
Myotis velifer. Cave myotis 
Southwestern U.S. 
Myotis volans. Long-legged myotis 
Western U.S. 
Myotis yumanensis, Yuma myotis 
Western U.S. 
Nyctinomops macrotis. Big free-tailed bat 
Southwestern U.S. 
Pteropus mariannus mariannus, Mariana fruit bat 
CNMI population 
Pteropus mariannus paganensis, Pagan Mariana fruit bat 
CNMI (Pagan population) 
Pteropus samoensis samoensis, Samoan flying fox 
American Samoa 
Stenoderma rufum. Red fruit bat 
Puerto Rico, U.S. Virgin Islands 
