O’SHEA, CRYAN & BOGAN: UNITED STATES BAT SPECIES OF CONCERN 
125 
west. Occupancy was determined using captures in mist nets and echolocation recordings during 
four surveys at 51 carefully selected sites in Washington, Oregon, and northern California, and esti¬ 
mated based on a series of habitat models (including successional stage and conservation reserve 
categories) that were ranked using Akaike’s Information Criteria. Long-eared myotis were detect¬ 
ed at 26 sites (observed occupancy of 0.509). Model-averaged detection probability estimates were 
0.239 ± 0.06 (SE), the lowest of eight species sampled, and overall occupancy estimates were 0.782 
±0.19 (SE) using the best-ranking model. Point estimates of occupancy were higher in late suc¬ 
cession/old growth habitat (Weller, 2008). Increased precision would have been possible with 
greater numbers of surveys per site and greater numbers of sites, or perhaps by increasing capture 
success or the number of recorded echolocation calls that are identifiable to species (Weller, 2008). 
Species dynamic distribution models were constructed using Bayesian hierarchical modeling 
techniques for 12 species of bats in Washington and Oregon based on an eight-year monitoring pro¬ 
gram; bat activity was sampled with mist nets and acoustic detectors, and the analysis accounted 
for detectability and annual turnover in bat occurrence (Rodhouse et al., 2015). This species did not 
show a decline in occurrence probabilities with time (Rodhouse et al., 2015). 
Management Practices and Concerns. — Waldien et al. (2000) and Amett and Hayes 
(2009) recommended the following management practices for maintaining roosting habitat of long¬ 
eared myotis and some other species of bats in the western Cascades of Oregon and Washington. 
Forest management should emphasize maintaining large-diameter conifer snags in early to inter¬ 
mediate stages of decay that are easily accessed by bats. Snags should be exposed to moderate to 
high levels of solar radiation by protruding above the canopy, or having lower canopy closure or 
being situated near gaps and edges. Snags should be retained in clusters, particularly where they 
are in upland habitats near water. Retention of large green trees and snag creation should be prac¬ 
ticed, and management should maintain remnant patches of structurally diverse and typically older 
forest stands (for example, greater than 40 years old) with large snags (Waldien et al., 2000; Amett 
and Hayes, 2009). Thinning of densely stocked stands to accelerate development of large-diameter 
trees for future roosts, and creation of gaps to increase solar radiation were also recommended. 
Although use of stumps as roosts for this species is important in younger stands, stumps are viewed 
as more ephemeral and less valuable sites for roosts than snags. This is because the more recently 
cut stumps do not provide roosts in early years (bark has not exfoliated) and are soon made less 
accessible or shaded as successional vegetation develops. However, the latter can be ameliorated 
by removal of vegetation around stumps, particularly those in natural openings and on steeper 
slopes (Waldien et al., 2000). 
Long-eared myotis will use artificial roosts constmcted to mimic exfoliating bark on snags in 
ponderosa pine forests in northern Arizona, including maternity groups of at least seven bats 
(Chambers et al., 2002; Mering and Chambers, 2012). In studies of several species of bats (includ¬ 
ing this species) roosting under loose bark or in lightning-caused cracks in ponderosa pine snags 
in northern Arizona, Rabe et al. (1998a) recommended measures to help recmit snags with loose 
bark as bat roosts. They suggested that forest management should retain large trees that die in 
place, thin stands of small trees to allow faster development of larger trees, and kill live large trees 
in areas of low snag density to hasten roost development. Prescribed fire but with protection of 
existing snags also may help promote development of future snags (Rabe et al., 1998a). 
Myotis leibii — Eastern small-footed 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 
