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Maternity Colony of Eastern Small-footed Myotis (Myotis
leibii) in a Historic Building
Joy M. O’Keefe1,2,* and Michael LaVoie3
Abstract - We report a maternity colony of the rare bat, Myotis leibii (Eastern Small-footed Myotis),
in a high-elevation cabin in western North Carolina. Because Eastern Small-footed Myotis
maternity colonies may typically roost in rock crevices, they are difficult to observe and are not
well documented. This cabin provides a variety of roost locations (e.g., shutters, attic, boarded
windows) for bats in a stable structure in a densely forested landscape.
Little is known about summer roost selection of Myotis leibii Audubon and Bachman
(Eastern Small-footed Myotis), which is thought to be one of the rarest bats in the United
States (Best and Jennings 1997) and is listed as a vulnerable species in North Carolina
(LeGrand et al. 2008). In the northeastern United States, Myotis bat populations have
declined significantly due to White-nose Syndrome, an emerging infectious disease that
is causing local extinctions of cave-wintering bat species (Veilleux 2008). A better understanding
of the summer roosting ecology of Eastern Small-footed Myotis may be critical
to conservation and recovery of this species.
Rock crevices are considered preferred natural summer roosts for Eastern Smallfooted
Myotis (Best and Jennings 1997); in the only published radio telemetry study
on the species, Johnson and Gates (2008) found individual females roosting alone in
crevices in rock outcrops in shale barrens near a hibernaculum. Most reports of Eastern
Small-footed Myotis summer roost locations are unpublished anecdotes. For example,
in New Hampshire, maternity colonies of ≤13 Eastern Small-footed Myotis have been
observed in rock outcrops (J. Veilleux, Franklin-Pierce University, Rindge, NH, unpubl.
data.) and, in Kentucky, a maternity colony of ≤20 bats were noted to be roosting in the
guardrail crevices in a concrete bridge (J. MacGregor, Kentucky Department of Fish and
Wildlife Resources, Frankfort, KY, unpubl. data). In North and South Carolina, Eastern
Small-footed Myotis have been observed in guardrail crevices of bridges and roadside
rock crevices (J.M. O’Keefe, pers. observ.), behind shutters on a residence (S. Bosworth,
Asheville, NC, unpubl. data.), and in a wood pile and picnic shelter (S. Loeb, USDA
Forest Service, Clemson, SC, unpubl. data). In July 1953, a colony of “about a dozen”
Eastern Small-footed Myotis were found behind a shed door in Renfrow County, ON,
Canada (Hitchcock 1955).
While conducting a mistnetting survey to assess Myotis sodalis Miller and Allen
(Indiana Myotis) presence, we documented a maternity colony of Eastern Small-footed
Myotis using a high-elevation historic cabin (1447 m) on property of the Eastern Band
of Cherokee Indians in Swain County, NC. The exact date of construction for the cabin
is unknown, but tribal records suggest it was constructed in the 1930s by the Civilian
Conservation Corps – Indian Division, and its structural integrity has been maintained.
The 60-m² stick-built cabin was in a 0.2-ha clearing on a ridgetop at the end of a 1.2-km
gravel road and surrounded by mature (>70 years old) oak-birch-hemlock (Quercus-Betula-
Tsuga) forest. The second- and third-growth mature forest within 3 km of the cabin
1USDA Forest Service, Southern Research Station, 233 Lehotsky Hall, Clemson University,
Clemson, SC, 29803. 2Current address - Department of Biology, 600 Chesnut Street, Indiana State
University, Terre Haute, IN 47809. 3Eastern Band of Cherokee Indians, PO Box 455, Cherokee, NC
28719. *Corresponding author - email@example.com.
Notes of the Southeastern Nat u ral ist, Issue 10/2, 2010
382 Southeastern Naturalist Vol. 10, No. 2
was lightly dissected by roads, rights-of-way, and small openings. Our mist nets were set
where the gravel road crossed a small right-of-way corridor ≈250 m from the cabin; we
set 2 nets (6 m x 5.6 m) ≈30 m apart and checked them every 10–15 min for 4.5–5.5 hours
after dusk on 10 and 11 July 2008. Prior to netting, we determined that bats were roosting
under the cedar shakes on the covered porch outside of the cabin; thus, we enclosed the
porch entrance with a 2.6- x 2.6-m net and monitored this net continuously for 30 minutes
after dusk on 10 July 2008.
We identified bats to species and recorded sex, age, reproductive condition, mass (g),
and forearm length (mm). Degree of ossification of the finger joints was used to assess
age (juvenile or adult, Anthony 1988). Some bats were banded with a unique aluminum
forearm band (USFS-SRS or USFS-NC, Porzana Ltd., East Sussex, UK), and we used a
3-mm biopsy punch to take 2 wing punches from each captured bat; these punches served
as a temporary mark for bats not banded. While handling bats, we followed the guidelines
of the American Society of Mammalogists for the use of wild mammals in research (Gannon
et al. 2007), and all bats were released at the point of capture.
We captured 38 bats over 2 net nights: 1 Eptesicus fuscus Beauvois (Big Brown
Bat), 2 Lasiurus borealis Muller (Eastern Red Bat), 33 Eastern Small-footed Myotis,
1 Myotis lucifugus LeConte (Little Brown Myotis), and 1 Myotis septentrionalis
Trouessart (Northern Long-eared Myotis). Only Eastern Small-footed Myotis (n = 18)
were captured in the net set at the doorway to the cabin porch, while Eastern Smallfooted
Myotis and other species were captured in nets over the road on both nights.
Most (n = 22) Eastern Small-footed Myotis were adult females that were either lactating
or post-lactating. We also captured 1 non-reproductive adult male, 3 juvenile males,
and 7 juvenile females. Six juvenile Eastern Small-footed Myotis (3 male, 3 female)
were banded. One banded juvenile female was captured in the cabin net on 10 July and
recaptured in a road net on 11 July.
On 4 May 2010, we conducted a visual inspection and emergence count at the cabin
to assess colony presence and size. We observed bats roosting in 2 places inside the
cabin; 2–4 Eastern Small-footed Myotis were in a closet and ≥10 bats (undetermined
species) were in the attic. Six observers stationed around the cabin observed ≈92 bats
exiting from 4 points in the cabin. Forty-four bats exited from 2 holes leading to the
attic, 31 came from under porch shingles and an attic access point beside the chimney,
and 17 bats emerged from behind a boarded window. Because we did not handle the
bats, we cannot be certain that all of the bats exiting the cabin were Eastern Smallfooted
Based on published literature and conversations with other biologists who study Eastern
Small-footed Myotis, we believe this cabin has housed a relatively large maternity
colony of Eastern Small-footed Myotis (>18 individuals) for ≥3 years. Larger aggregations
of Eastern Small-footed Myotis have been found in winter; for example, 47 used an
abandoned railroad tunnel in Maryland (Johnson and Gates 2008), and 108 were found
hibernating in a mine in Haywood County, NC (K. Weeks, North Carolina Wildlife Resources
Commission, Asheville, NC, pers. comm.).
There is no evidence that Eastern Small-footed Myotis are using 2 newer, well-sealed
buildings ≤20 m from the cabin or that other bat species are using the historic cabin. The
maternity colony of Eastern Small-footed Myotis may show long-term fidelity (Lewis
1995) to the cabin because it is a permanent stable structure and because it offers a variety
of roost locations that likely vary in temperature regimes. When considering the
surrounding landscape, the cabin may be a surrogate for natural roosts like rock crevices,
which are sparse in the area within 5 km of the cabin. Further, the dense mature forest
2011 Southeastern Naturalist Notes 383
surrounding the cabin may be ideal foraging grounds for Eastern Small-footed Myotis
(Johnson et al. 2009).
Acknowledgments. We thank Josh Parker (Eastern Band of Cherokee Indians), Dylan
Horvath (Binghamton University), Dorothy Brown (University of North Carolina,
Asheville), Vanessa Rojas (University of Michigan, Flint), and Matthew Conzett for field
assistance. Comments from two anonymous reviewers greatly improved the manuscript.
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