O’SHEA, CRYAN & BOGAN: UNITED STATES BAT SPECIES OF CONCERN 
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populations and were from locations scattered across the recognized distribution of M. occultus, 
ranging from Grant County in southwestern New Mexico to Las Animas County in southeastern 
Colorado (Dewey, 2006), making interpretation difficult. Additional phylogenetic analysis of the 
full 1,140-base-pair mitochondrial cytochrome b gene (but including only one sample from New 
Mexico) supported the divergence of M. occultus as a species distinct from M. lucifugus, although 
a much closer relationship was indicated by analysis of the nuclear Rag 2 gene (Stadlemann et al., 
2007). 
Based on morphological analysis of multiple cranial characters of 268 Arizona myotis from 
New Mexico and southern Colorado, as well as specimens of M. lucifugus carissima from 
Wyoming, findings of Valdez (2006) supported the specific status of M. occultus and suggested that 
the southern Colorado population was more isolated and smaller in size than New Mexico popula¬ 
tions (see also “Foraging and Dietary Analysis” below). 
Habitats and Relative Abundance.— Findley et al. (1975) concluded that Arizona myotis 
were usually found in association with large permanent water sources and that vegetation zones 
were seemingly unimportant in determining their distribution. Other authors also have noted that 
roosts are often located near streams, rivers, or lakes in a wide variety of habitat types (for exam¬ 
ple, Stager, 1943b; Mumford, 1957; Hayward, 1963; Geluso and Studier, 1979; Geluso and Mink, 
2009). They are often reported at higher elevation sites (1800-2750 m; Barbour and Davis, 1969, 
1970) but are also known from lowland deserts (for example, Geluso and Mink, 2009; Calvert and 
Neiswenter, 2012) as well as intermediate elevations. 
Arizona: This species was the fourth most frequently captured (115 individuals) among 11 
species and 1,119 individuals documented in mist nets over water in ponderosa pine forest habitat 
in northern Arizona, and the third most frequently captured species (109 captures among 554 bats 
of 15 species) in northern Arizona ponderosa pine-Gambel oak ( Quercus gambelii) habitat (Mor¬ 
rell et al., 1999). They also ranked third most frequently captured (54 captures among 353 bats of 
15 species) in ponderosa pine forests on the Tonto National Forest in central Arizona at 1,350 to 
1,930 meters elevation along the East Verde River below the Mogollon Rim (Lutch, 1996). They 
ranked fourth in relative abundance (199 captures among 1,441 individuals of 14 species) captured 
in combined low severity and high severity bum areas (two and three years post-fire) in ponderosa 
pine forest at 2,345 to 2,686 meters elevation in the Apache-Sitgraves National Forests in east-cen¬ 
tral Arizona (Saunders, 2015). A mist-netting survey in five riparian canyons in the Huachuca 
Mountains in southern Arizona during 1993 and 1994, however, found them to rank last in relative 
abundance among 13 species (one capture out of 145 individuals; Sidner and Davis, 1994). These 
bats have been captured in flight among pockets of human-restored cottonwood-willow riparian 
habitats along the lower Colorado River in southwestern Arizona, vegetation types that have been 
much reduced due to human influences (Calvert and Neiswenter, 2012). 
Colorado and New Mexico: Arizona myotis ranked sixth most abundant among 15 species 
captured (100 out of 1,996 individuals) at Mesa Verde National Park in southwestern Colorado dur¬ 
ing 2006 and 2007 (O’Shea et al., 2011a). In an earlier study at Mesa Verde National Park during 
1989-1994, they ranked low in relative abundance, with one capture among 189 bats of 11 species 
(Chung-MacCoubrey and Bogan, 2003). Bogan et al. (1998) did not document any of these bats 
among 15 species and 1,532 bats captured in the Jemez Mountains in the north-central part of the 
state. Arizona myotis ranked second in relative abundance (30 bats captured among 130 individu¬ 
als of six species) netted over water along the middle Rio Grande in the Bosque del Apache Nation¬ 
al Wildlife Refuge in central New Mexico (Chung-MacCoubrey, 1999). They ranked as lowest in 
abundance among 16-17 species (one bat out of 855 individuals) captured in mist nets over ponds 
during 1970 at Nogal Canyon in the San Mateo Mountains, Socorro County, New Mexico, in habi¬ 
tats described as pinyon-juniper, pine-oak woodlands, and mixed-conifer forest (Black, 1974). 
