136 
PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES 
Series 4, Volume 65, Supplement I 
Acoustic surveys for this species at Fort Drum in New York during active seasons in 2011 and 
2012 failed to detect their presence despite a known history of occurrence prior to the advent of 
white-nose syndrome, perhaps indicating a negative impact of the disease on the population (Cole¬ 
man et al., 2014). Relative abundance surveys of bat communities in West Virginia prior to and 
since white-nose syndrome showed a six-fold drop in numbers of these bats captured per mist-net 
night (Francl et al., 2012). Similarly, capture rates of this species showed a significant drop 
between samples taken in mist nets early versus later during the epizootic at a study area in New 
Hampshire (Moosman et al., 2013). 
Recent evidence suggests that eastern small-footed myotis may be less restricted to use of 
caves than was previously appreciated; widespread year-round use of roosts in rock outcrops and 
talus slopes could strongly bias prior understanding of population size and trend (see “Roosting 
Habits” above). Therefore Moosman et al. (2015) explored the feasibility of assessing abundance 
of these bats during summer by netting at talus slopes, visually searching for roosting bats at such 
areas, and using randomly placed quadrats over talus slopes to obtain an index of local abundance. 
They conducted field work on talus slopes in the Blue Ridge Mountains of Virginia and used time- 
constrained searches to visually inspect crevices in rocks and sometimes extracted roosting bats in 
talus slopes identified through satellite imagery. They also systematically placed mist nets at talus 
fields and randomly placed circular quadrats over talus areas to estimate density (Moosman et al., 
2015). In summer, they discovered 3.1 ± 1.1 (SE) bats per person-search hour, with 27 bats of both 
sexes discovered (20 solitary, two pairs, and one roost with three) at 23 roosts. Roosting bats were 
found between mid-March and late October but not during winter searches, when authors specu¬ 
lated the bats might possibly hibernate deeper below the surface of the talus. Thirteen bats or 4.3 
±2.1 (SE) bats per net-night were captured in the systematically placed nets. Surveys of random 
quadrats at one 3.0-hectare talus slope revealed six bats in 337 searched crevices, which were 
scaled up to 48-343 bats (depending on method) in an area with an estimated 8,873-11,018 suit¬ 
able crevices (Moosman et al., 2015). Subsequent research on these talus slopes compared detec¬ 
tion probabilities based on visual searches using belt transects, mist netting, and passive acoustic 
detection (Huth et al., 2015). Detection probabilities were 0.00 for acoustic sampling, 0.75 for mist 
netting, and 0.91 for visual searches (Huth et al., 2015). 
Management Practices and Concerns. — This species was recently petitioned for listing 
under the U.S. Endangered Species Act of 1973, primarily because of its apparent rarity, loss or 
degradation of habitat, threats from white-nose syndrome, as well as other natural and anthro¬ 
pogenic threats and perceived inadequacy of protections (Center for Biological Diversity, 2010; 
U.S. Fish and Wildlife Service, 2011). The resultant finding was that listing was not warranted 
because there was no evidence of a concentration of threats in a significant portion of its range, or 
that its range had been significantly contracted (U.S. Fish and Wildlife Service, 2013b). The recent 
findings that the eastern small-footed myotis roosts in talus or talus-like areas may warrant more 
attention for future management. 
Myotis occultus — Arizona myotis (Family Vespertilionidae) 
Conservation Status. — National and International Designations: U.S. Fish and Wildlife 
Service (1994, 1996a,b): Species of Concern (inactive, former Category 2 candidate for listing 
under the U.S. Endangered Species Act, as M. lucifugus occultus). Bureau of Land Management 
(2017): Sensitive Species (Arizona state office). International Union for the Conservation of Nature 
(2017): Least Concern (as M. occultus ). NatureServe (2017): Rounded Global Status G4, Appar¬ 
ently Secure (as M. occultus ). 
State Designations: Arizona Game and Fish Department (2012): Species of Greatest Conser- 
