O’SHEA, CRYAN & BOGAN: UNITED STATES BAT SPECIES OF CONCERN 
199 
Arizona: Big free-tailed bats ranked as least captured (one bat among 353 individuals of 15 
species) in ponderosa pine forests at 1,350 to 1,930 meters elevation along the East Verde River 
below the Mogollon Rim on the Tonto National Forest in central Arizona (Lutch, 1996). In north¬ 
ern Arizona, this species was captured in several regions in mist nets placed over large stock ponds 
(14 by 18 meters or greater in size; smaller sizes did not yield captures) at elevations ranging from 
870 to 2,700 meters in habitats ranging from Great Basin desert vegetation to spruce-fir forests 
(Corbett et al., 2008). Five bats radio tracked in one area during nightly flights were located over 
desert scrub vegetation and to a lesser extent pinon-juniper woodlands and ponderosa pine forest, 
and used canyons and edges of plateaus as travel corridors (Corbett et al., 2008). They ranked thir¬ 
teenth in abundance among 17 species of bats (five captured of 1,171 total bats netted) taken over 
water in mostly ponderosa pine and pinon-juniper habitats of the Arizona Strip in northwestern Ari¬ 
zona (Herder, 1998). 
California and Nevada: Records of big free-tailed bats in California have been very rare, 
without captures in mist nets and with few presumed acoustic records (Pierson and Rainey, 1998c). 
They were only detected acoustically in one sample at the Nevada Test Site, although over 2,000 
individuals of 14 other species were documented with mist nets (Hall, 2000). 
Colorado and Utah: None were captured in a mist-netting survey over water at Mesa Verde 
National Park in southwestern Colorado during which 1,996 individuals of 15 species were cap¬ 
tured, but hundreds of passes were recorded by ultrasonic detectors throughout the summer 
(O’Shea et al., 2011a). Echolocation calls of this species also were recorded without capture in 
multiple canyons elsewhere in southwestern Colorado (Navo and Gore, 2001). In far western Col¬ 
orado, this species ranked thirteenth in relative abundance of 16 species (4 captures among 899 
bats) at Colorado National Monument and the adjacent Mclnnis Canyons National Conservation 
Area during three summers of netting; nets were placed over small ephemeral pools in deep slick- 
rock canyons within primarily pinon-juniper woodland and riparian habitats (Neubaum, 2017). Big 
free-tailed bats were uncommon on the Colorado Plateau of the Four Comers Region, but they can 
be abundant at localized capture sites in the general vicinity of roosts in cliffs (Mollhagen and 
Bogan, 2016). At Arch Canyon on the Colorado Plateau in southeastern Utah, they were the sec¬ 
ond most abundant species captured in mist nets, with 69 bats captured among 295 individuals of 
15 species taken at elevations ranging from 1,474 to 1,707 meters; a large colony was known to 
roost in cliffs in the region (Mollhagen and Bogan, 2016). 
New Mexico: Big free-tailed bats were least frequently captured (a total of one) among 1,595 
bats of 20 species taken in the Mogollon Mountains of western New Mexico and adjacent Arizona 
(Jones, 1965). In a separate analysis limited to three sites over water in western New Mexico and 
including additional years of sampling, they ranked fifteenth of 19 species (four captures among 
1,004 individuals) and were taken at two sites, one site in riparian hardwoods among mesquite- 
juniper woodlands at 1,465 meters and another site in pine-spmce-fir forest at 2,500 meters eleva¬ 
tion (Jones and Suttkus, 1972). Fifteen individuals captured in mist nets over water in the Jemez 
Mountains of New Mexico were taken in ponderosa pine-mixed conifer forests at elevations of 
2,423 and 2,479 meters, ranking ninth in relative abundance among 15 species and 1,532 individ¬ 
uals (Bogan et al., 1998). Echolocation activity of these bats was detected over riparian, conifer, 
pinon-juniper, and previously (20 years) intensely burned ponderosa pine habitat in the Jemez 
Mountains (Ellison et al., 2005). A survey that took place at 37 sites across several habitat types in 
much of New Mexico in 2006 yielded 1,752 bats of 21 species, but only one big free-tailed bat was 
captured (Geluso, 2006, 2017). 
Texas: At one site in Big Bend National Park in southwestern Texas, this was the most abun¬ 
dant species taken in mist nets over water (391 among 1,052 bats of 15 species captured, whereas 
