Endangered and Threatened Wildlife and Plants; 12-Month Finding on a Petition To List the Eastern Small-Footed Bat and the Northern Long-Eared Bat as Endangered or Threatened Species; Listing the Northern Long-Eared Bat as an Endangered Species, 61045-61080 [2013-23753]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 78, Number 191 (Wednesday, October 2, 2013)]
[Proposed Rules]
[Pages 61045-61080]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-23753]



[[Page 61045]]

Vol. 78

Wednesday,

No. 191

October 2, 2013

Part III





Department of the Interior





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Fish and Wildlife Service





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50 CFR Part 17





 Endangered and Threatened Wildlife and Plants; 12-Month Finding on a 
Petition To List the Eastern Small-Footed Bat and the Northern Long-
Eared Bat as Endangered or Threatened Species; Listing the Northern 
Long-Eared Bat as an Endangered Species; Proposed Rule

Federal Register / Vol. 78 , No. 191 / Wednesday, October 2, 2013 / 
Proposed Rules

[[Page 61046]]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R5-ES-2011-0024; 4500030113]
RIN 1018-AY98


Endangered and Threatened Wildlife and Plants; 12-Month Finding 
on a Petition To List the Eastern Small-Footed Bat and the Northern 
Long-Eared Bat as Endangered or Threatened Species; Listing the 
Northern Long-Eared Bat as an Endangered Species

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule; 12-month finding.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
12-month finding on a petition to list the eastern small-footed bat 
(Myotis leibii) and the northern long-eared bat (Myotis 
septentrionalis) as endangered or threatened under the Endangered 
Species Act of 1973, as amended (Act) and to designate critical 
habitat. After review of the best available scientific and commercial 
information, we find that listing the eastern small-footed bat is not 
warranted but listing the northern long-eared bat is warranted. 
Accordingly, we propose to list the northern long-eared bat as an 
endangered species throughout its range under the Act. We also 
determine that critical habitat for the northern long-eared bat is not 
determinable at this time. This proposed rule, if finalized, would 
extend the Act's protections to the northern long-eared bat. The 
Service seeks data and comments from the public on this proposed 
listing rule for the northern long-eared bat.

DATES: We will consider comments received or postmarked on or before 
December 2, 2013. Comments submitted electronically using the Federal 
eRulemaking Portal (see ADDRESSES section, below) must be received by 
11:59 p.m. Eastern Time on the closing date. We must receive requests 
for a public hearing, in writing, at the address shown in the FOR 
FURTHER INFORMATION CONTACT section by November 18, 2013.

ADDRESSES: You may submit comments by one of the following methods:
    (1) In the Search box, enter Docket No. FWS-R5-ES-2011-0024, which 
is the docket number for this rulemaking. Then, in the Search panel on 
the left side of the screen, under the Document Type heading, click on 
the Proposed Rules link to locate this document. You may submit a 
comment by clicking on ``Comment Now!'' If your comments will fit in 
the provided comment box, please use this feature of https://www.regulations.gov, as it is most compatible with our comment review 
procedures. If you attach your comments as a separate document, our 
preferred file format is Microsoft Word. If you attach multiple 
comments (such as form letters), our preferred format is a spreadsheet 
in Microsoft Excel.
    (2) By hard copy: Submit by U.S. mail or hand-delivery to: Public 
Comments Processing, Attn: FWS-R5-ES-2011-0024; Division of Policy and 
Directives Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax 
Drive, MS 2042-PDM; Arlington, VA 22203.
    We request that you send comments only by the methods described 
above. We will post all information received on https://www.regulations.gov. This generally means that we will post any 
personal information you provide us (see the Information Requested 
section below for more details).

FOR FURTHER INFORMATION CONTACT: Peter Fasbender, Field Supervisor, 
U.S. Fish and Wildlife Service, Green Bay Ecological Services Office, 
2661 Scott Tower Dr., New Franken, Wisconsin, 54229; by telephone (920) 
866-3650 or by facsimile (920) 866-1710. mailto: If you use a 
telecommunications device for the deaf (TDD), please call the Federal 
Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Executive Summary

    Why we need to publish a rule. Under the Act, if a species is 
determined to be an endangered or threatened species throughout all or 
a significant portion of its range, we are required to promptly publish 
a proposal in the Federal Register and make a determination on our 
proposal within one year. Listing a species as an endangered or 
threatened species can only be completed by issuing a rule.
    This document consists of:
     Our status review and finding that listing is warranted 
for the northern long-eared bat and not warranted for the eastern 
small-footed bat.
     A proposed rule to list the northern long-eared bat as an 
endangered species. This rule assesses best available information 
regarding the status of and threats to the northern long-eared bat.
    The basis for our action. Under the Act, we can determine that a 
species is an endangered or threatened species based on any of five 
factors: (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence. We have determined that the northern long-eared 
bat is in danger of extinction, predominantly due to the threat of 
white-nose syndrome (Factor C). However, other threats (Factors A, B, 
E) when combined with white-nose syndrome heighten the level of risk to 
the species.
    We will seek peer review. We are seeking comments from 
knowledgeable individuals with scientific expertise to review our 
analysis of the best available science and application of that science 
and to provide any additional scientific information to improve this 
proposed rule. Because we will consider all comments and information we 
receive during the comment period, our final determination may differ 
from this proposal.

Information Requested

    We intend that any final action resulting from this proposed rule 
will be based on the best scientific and commercial data available and 
be as accurate and as effective as possible. Therefore, we request 
comments or information from other concerned Federal and State 
agencies, the scientific community, or any other interested party 
concerning this proposed rule. We particularly seek comments regarding 
the northern long-eared bat concerning:
    (1) The species' biology, range, and population trends, including:
    (a) Habitat requirements for feeding, breeding, and sheltering;
    (b) Genetics and taxonomy;
    (c) Historical and current range, including distribution patterns;
    (d) Historical and current population levels, and current and 
projected trends; and
    (e) Past and ongoing conservation measures for the species, its 
habitat, or both.
    (2) Any information on the biological or ecological requirements of 
the species, and ongoing conservation measures for the species and its 
habitat.
    (3) Biological, commercial trade, or other relevant data concerning 
any threats (or lack thereof) to this species and regulations that may 
be addressing those threats.
    (4) Current or planned activities in the areas occupied by the 
species and possible impacts of these activities on this species.

[[Page 61047]]

    (5) Additional information regarding the threats to the species 
under the five listing factors, which are:
    (a) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (b) Overutilization for commercial, recreational, scientific, or 
educational purposes;
    (c) Disease or predation;
    (d) The inadequacy of existing regulatory mechanisms; and
    (e) Other natural or manmade factors affecting its continued 
existence.
    (6) The reasons why areas should or should not be designated as 
critical habitat as provided by section 4 of the Act (16 U.S.C. 1531 et 
seq.), including the possible risks or benefits of designating critical 
habitat, including risks associated with publication of maps 
designating any area on which this species may be located, now or in 
the future, as critical habitat.
    (7) The following specific information on:
    (a) The amount and distribution of habitat for northern long-eared 
bat;
    (b) What areas, that are currently occupied and that contain the 
physical and biological features essential to the conservation of this 
species, should be included in a critical habitat designation and why;
    (c) Special management considerations or protection that may be 
needed for the essential features in potential critical habitat areas, 
including managing for the potential effects of climate change;
    (d) What areas not occupied at the time of listing are essential 
for the conservation of this species and why;
    (e) The amount of forest removal occurring within known summer 
habitat for this species;
    (f) Information on summer roost habitat requirements that are 
essential for the conservation of the species and why; and
    (g) Information on species winter habitat (hibernacula) features 
and requirements for the species.
    (8) Information on the projected and reasonably likely impacts of 
changing environmental conditions resulting from climate change on the 
species and its habitat.
    Please note that submissions merely stating support for or 
opposition to the action under consideration without providing 
supporting information, although noted, will not be considered in 
making a determination, as section 4(b)(1)(A) of the Act directs that 
determinations as to whether any species is an endangered or threatened 
species must be made ``solely on the basis of the best scientific and 
commercial data available.''
    You may submit your comments and materials concerning this proposed 
rule by one of the methods listed in ADDRESSES. We request that you 
send comments only by the methods described in the ADDRESSES section. 
If you submit information via https://www.regulations.gov, your entire 
submission--including any personal identifying information--will be 
posted on the Web site. If your submission is made via a hardcopy that 
includes personal identifying information, you may request at the top 
of your document that we withhold this information from public review. 
However, we cannot guarantee that we will be able to do so. We will 
post all hardcopy submissions on https://www.regulations.gov. Please 
include sufficient information with your comments to allow us to verify 
any scientific or commercial information you include.
    Comments and materials we receive, as well as supporting 
documentation we used in preparing this proposed rule, will be 
available for public inspection on https://www.regulations.gov, or by 
appointment, during normal business hours, at the U.S. Fish and 
Wildlife Service, Green Bay, Wisconsin Field Office (see FOR FURTHER 
INFORMATION CONTACT).

Background

    Section 4(b)(3)(B) of the Act requires that, for any petition to 
revise the Federal Lists of Threatened and Endangered Wildlife and 
Plants that contains substantial scientific or commercial information 
that listing a species may be warranted, we make a finding within 12 
months of the date of receipt of the petition on whether the petitioned 
action is: (a) Not warranted; (b) warranted; or (3) warranted, but the 
immediate proposal of a regulation implementing the petitioned action 
is precluded by other pending proposals to determine whether any 
species is endangered or threatened, and expeditious progress is being 
made to add or remove qualified species from the Federal Lists of 
Endangered and Threatened Wildlife and Plants. In this document, we 
have determined that the petitioned action to list the eastern small-
footed bat is not warranted, but listing the northern long-eared bat is 
warranted and; therefore, we are publishing a proposed rule to list the 
northern long-eared bat.

Previous Federal Actions

    On September 18, 1985 (50 FR 37958), November 21, 1991 (56 FR 
58804), and November 15, 1994 (59 FR 58982), the Service issued notices 
of review identifying the eastern small-footed bat as a ``category-2 
candidate'' for listing under the Act. However, on December 5, 1996 (50 
FR 64481), the Service discontinued the practice of maintaining a list 
of species regarded as ``category-2 candidates,'' that is, taxa for 
which the Service had insufficient information to support issuance of a 
proposed listing rule.
    On January 21, 2010, we received a petition from the Center for 
Biological Diversity, requesting that the eastern small-footed bat and 
northern long-eared bat be listed as endangered or threatened and that 
critical habitat be designated under the Act. The petition clearly 
identified itself as such and included the requisite identification 
information for the petitioner, as required by 50 CFR 424.14(a). In a 
February 19, 2010, letter to the petitioner, we acknowledged receipt of 
the petition and stated that we would review the petitioned request for 
listing and inform the petitioner of our determination upon completion 
of our review. On June 23, 2010, we received a notice of intent to sue 
(NOI) from the petitioner for failing to make a timely 90-day finding. 
In a letter dated July 20, 2010, we responded to the NOI, stating that 
we had assigned lead for the two bat species to the Services' Midwest 
and Northeast Regions, and that although completing the 90-day finding 
within the 90 days following our receipt of the petition was not 
practicable, the Regions were recently allocated funding to work on the 
findings and had begun review of the petition. On June 29, 2011, we 
published in the Federal Register (76 FR 38095) our finding that the 
petition to list the eastern small-footed bat and northern long-eared 
bat presented substantial information indicating that the requested 
action may be warranted, and we initiated a status review of the 
species. On July 12, 2011, the Service filed a proposed settlement 
agreement with the Center for Biological Diversity in a consolidated 
case in the U.S. District Court for the District of Columbia. The 
settlement agreement was approved by the court on September 9, 2011. As 
part of this settlement agreement, the Service agreed to complete a 
status review for the eastern small-footed bat and northern long-eared 
bat by September 30, 2013, and if warranted for listing, publish a 
proposed listing rule also by that date.

Species Information

Eastern Small-Footed Bat
Taxonomy and Species Description
    The eastern small-footed bat (Myotis leibii) belongs to the Order 
Chiroptera,

[[Page 61048]]

Suborder Microchiroptera, and Family Vespertilionidae (Best and 
Jennings 1997, p. 1). The eastern small-footed bat is considered 
monotypic, whereby no subspecies has been recognized (van Zyll de Jong 
1984, p. 2525). This species has been identified by different 
scientific names: Vespertilio leibii (Audubon and Bachman 1842, p. 284) 
and Myotis subulatus (Miller and Allen 1928, p. 164). This species also 
has been identified by different common names: Leib's bat (Audubon and 
Bachman 1842, p. 284), least brown bat (Mohr 1936, p. 62), and Leib's 
masked bat or least bat (Hitchcock 1949, p. 47). The Service agrees 
with the treatment in Best and Jennings (1997, p. 1) regarding the 
scientific and common names and will refer to this species as eastern 
small-footed bat and recognizes it as a listable entity under the Act.
    The eastern small-footed bat is one of the smallest North American 
bats, weighing from 3 to 8 grams (g) (0.1 to 0.3 ounces (oz)) (Merritt 
1987, p. 94). Total body length is from 73 to 85 millimeters (mm) (2.9 
to 3.4 inches (in)), tail length is from 31 to 34 mm (1.2 to 1.3 in), 
forearm length is from 30 to 36 mm (1.2 to 1.4 in), and wingspan is 
from 212 to 248 mm (8.4 to 9.8 in) (Barbour and Davis 1969, p. 103; 
Merritt 1987, p. 94; Erdle and Hobson 2001, p. 6; Amelon and Burhans 
2006, p. 57). Eastern small-footed bats are recognized by their short 
hind feet (less than 8 mm (0.3 in)), short ears (less than 15 mm (0.6 
in)), black facial mask, black ears, keeled calcar (a spur of cartilage 
that helps spread the wing membrane), and small flattened skull 
(Barbour and Davis 1969, p. 103; Best and Jennings 1997, p. 1). The 
wings and interfemoral membrane (the wing membrane between the tail and 
hind legs) are black. The dorsal fur is black at the roots and tipped 
with light brown, giving it a dark yellowish-brown appearance. The 
ventral fur is gray at the roots and tipped with yellowish-white 
(Audubon and Bachman 1842, pp. 284-285).
Distribution and Abundance
    The eastern small-footed bat occurs from eastern Canada and New 
England south to Alabama and Georgia and west to Oklahoma. The species' 
range includes 26 states and 2 Canadian provinces, including Alabama, 
Arkansas, Connecticut, Delaware, Georgia, Illinois, Indiana, Kentucky, 
Maine, Maryland, Massachusetts, Mississippi, Missouri, New Hampshire, 
New Jersey, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, 
Rhode Island, South Carolina, Tennessee, Vermont, Virginia, West 
Virginia, Ontario, and Quebec. Relative to other species of bats in its 
range, eastern small-footed bats are considered uncommon (Best and 
Jennings 1997, p. 3). They historically have been considered rare 
because of their patchy distribution and generally low population 
numbers (Mohr 1932, p. 160). In areas with abundant summer habitat, 
however, they have been found to be relatively common (Brack et al., 
unpublished manuscript). Johnson et al. (2011, p. 99) observed that 
capture success decreased as the distance increased from suitable 
roosting habitat. Eastern small-footed bats have also been noted for 
their ability to detect and avoid mist nets, which are typically relied 
upon for summer bat surveys (Barbour and Davis 1974, p. 84), suggesting 
their numbers could be underrepresented (Tyburec 2012).
    Eastern small-footed bats have most often been detected during 
winter hibernacula (the areas where the bats hibernate during winter; 
primarily caves and mines) surveys (Barbour and Davis 1969, p. 103). 
Two-hundred eighty-nine hibernacula (includes cave and abandoned mine 
features only) have been identified across the species' range, though 
most contain just a few individuals. The majority of known hibernacula 
occur in Pennsylvania (n=55), New York (n=53), West Virginia (n=50), 
Virginia (n=33), Kentucky (n=26), and North Carolina (n=25), but 
hibernacula are also known from Tennessee (approximately 12), Arkansas 
(n=9), Maryland (n=7), Vermont (n=6), Missouri (n=3), Maine (n=2), 
Massachusetts (n=2), New Hampshire (n=2), New Jersey (n=2), Indiana 
(n=1), and Oklahoma (n=1). In Vermont, eastern small-footed bats were 
consistently found in very small numbers and often not detected at all 
during periodic surveys of hibernacula (Trombulak et al. 2001, pp. 53-
57). Their propensity for hibernating in cracks and crevices in cave 
and mine floors and ceilings may also mean they are more often 
overlooked than other cave-hibernating bat species. The largest number 
of hibernating individuals ever reported for the species was 2,383, 
which were found in a mine in Essex County, New York (Herzog 2013, 
pers. comm.).
    In Pennsylvania, eastern small-footed bats were observed at 55 of 
480 (12 percent) hibernacula from 1984 to 2011, accounting for only 0.1 
percent of the total bats observed during winter hibernacula surveys. 
The number of eastern small-footed bats observed per site fluctuates 
annually and ranges from 1 to 46 (mean = 4, median = 1). Summer mist-
net surveys also confirm that eastern small-footed bats are observed 
less frequently than other bat species. From 1995 to 2011, of the 7,007 
bat mist-net surveys conducted in Pennsylvania, only 104 surveys (2 
percent) include eastern small-footed bat captures, representing only 
0.3 percent of the total bats captured (Butchkoski 2011, unpublished 
data). Of the other states within the species' range, seven states 
(Alabama, Connecticut, Delaware, Indiana, Massachusetts, Mississippi, 
and Rhode Island) have no summer records, and of those States with 
summer records, the most have fewer than 20 capture locations (Service, 
unpublished data).
    Illustrating the potential for under-representation of the species 
during hibernacula surveys, the following is an example from one state. 
From 1939 to 1944, over 100 caves were surveyed in Pennsylvania (and a 
portion of West Virginia), and out of these, eastern small-footed bats 
were observed at only 7 sites, totaling 363 individuals. In 1978 and 
1979, the same seven caves were surveyed again, and no eastern small-
footed bats were observed (Felbaum et al. 1995, p. 24). However, 
surveys conducted from 1980 to 1988, found eastern small-footed bats 
inhabiting 21 hibernacula from an 8-county area in Pennsylvania (Dunn 
and Hall 1989, p. 169), and by 2011, surveys had confirmed presence at 
55 sites in a 14-county area (Pennsylvania Game Commission, unpublished 
data). This example is typical of the species' potential for 
fluctuation throughout its range.
Habitat
Winter Habitat
    Eastern small-footed bats have been observed most often 
overwintering in hibernacula that include caves and abandoned mines 
(e.g., limestone, coal, iron). Because they tolerate colder 
temperatures more so than other Myotis bats, they are most often 
encountered close to cave or mine entrances where humidity is low and 
temperature fluctuations may be high relative to more interior areas 
(Hitchcock 1949, p. 53; Barbour and Davis 1969, p. 104; Best and 
Jennings 1997, pp. 2-3; Veilleux 2007, p. 502). On occasion, however, 
they have been observed hibernating deep within cave interiors 
(Hitchcock 1965, p. 9; Gunier and Elder 1973, p. 490). In Pennsylvania, 
caves containing wintering populations of eastern small-footed bats 
have been found in hemlock-dominated forests in the foothills of 
mountains that rise to 610 meters (m) (2000 feet (ft)) (Mohr 1936, p. 
63). Dunn and Hall (1989, p. 169) noted that 52 percent of Pennsylvania 
hibernacula

[[Page 61049]]

used by eastern small-footed bats were small caves of less than 150 m 
(500 ft) in length. Before it was commercialized, the cave in Fourth 
Chute, Ontario was home to a relatively large number of hibernating 
eastern small-footed bats (n = 434) and is described in Hitchcock 
(1949, pp. 47-54) as follows: ``the cave is in a limestone outcropping 
on the north bank of the Bonnechere River, at an elevation of 425 ft 
(130 m). Sinkholes and large openings to passages make this cave 
conspicuous. Most of the land immediately surrounding the cave area is 
open field or pasture, with wooded hills beyond. The part utilized by 
bats for hibernation lies farthest from the river, and is entered from 
one of the large, outside passageways through a narrow opening; the 
main passages are well ventilated by a through draft; the forests near 
Fourth Chute are mixed, with spruce and white cedar predominating among 
the conifers.'' Eastern small-footed bats were found in cold, dry, 
drafty locations at Fourth Chute, usually in narrow cracks in the cave 
wall or roof (Hitchcock 1949, p. 53).
    Winter habitat used by eastern small-footed bats may also include 
non-cave or non-mine features, such as rock outcrops and stone highway 
culverts. In Pennsylvania, eastern small-footed bats were observed 
hibernating multiple years during the months of January and March in a 
rock outcrop located high above the Juniata River. The bats were found 
in small cracks and crevices at the back of a 4.6-m (15-ft) depression 
in the rock outcrop. Big brown bats (Eptesicus fuscus) were also 
present. Temperatures within the cracks where bats were hibernating 
ranged from 1.7 to 8.3 [deg]C (35 to 47 [deg]F). Observers noted that 
it seemed a cold, unstable site for hibernating bats (Pennsylvania Game 
Commission, unpublished data). In West Virginia, an eastern small-
footed bat was observed in a crack in a rock outcrop about 1.5 to 1.8 m 
(5 to 6 ft) above the ground in February (Stihler 2012, pers. comm.). 
Sasse et al. (in press) reported a single female eastern small-footed 
bat hibernating inside a stone highway culvert underneath a highway in 
Arkansas. Mohr (1936, p. 64) noted fluctuations in the number of 
eastern small-footed bats observed at hibernacula during winter surveys 
conducted 2 to 3 weeks apart, suggesting bats left caves and mines 
during warmer winter periods only to return when it became colder. 
Consequently, eastern small-footed bats may be utilizing non-cave or 
non-mine rock features during mild or milder portions of winters, but 
to what extent they may be doing so is largely unknown.
Summer Habitat
    In the summer, eastern small-footed bats are dependent on emergent 
rock habitats for roosting and on the immediately surrounding forests 
for foraging (Johnson et al. 2009, p. 5). Eastern small-footed bats 
have been observed roosting singly or in small maternity colonies in 
talus fields and slopes, rock-outcrops, rocky ridges, sandstone 
boulders, shale rock piles, limestone spoil piles, rocky terrain of 
strip mine areas, and cliff crevices, but have also been found on 
humanmade structures such as buildings and expansion joints of bridges 
(Barbour and Davis 1969, p. 103; McDaniel et al. 1982, p. 93; Merritt 
1987, p. 95; MacGregor and Kiser 1998, p. 175; Roble 2004, p. 43; 
Amelon and Burhans 2006, p. 58; Chenger 2008a, p. 10; Chenger 2008b, p. 
6; Johnson et al. 2011, p. 100; Johnson and Gates 2008, p. 456; Hauser 
and Chenger 2010; Sanders 2010; Mumma and Capouillez 2011, p. 24; 
Thomson and O'Keefe 2011; Brack et al., unpublished manuscript). Other 
humanmade features exploited by eastern small-footed bats include rocky 
dams, road cuts, rocky mine lands, mines, and rock fields within 
transmission-line and pipeline clearings (Sanders 2011, pers. comm.; 
Johnson et al. 2011, p. 99; Thomson and O'Keefe 2011). Roost sites are 
most often located in areas with full solar exposure, but have also 
been found in areas with moderate to extensive canopy cover (Johnson et 
al. 2011, p. 100; Brack et al. unpublished manuscript, pp. 9-15; 
Thomson and O'Keefe 2012). In New Hampshire, eastern small-footed bats 
have been observed roosting between boulder crevices along the southern 
outflow of the Surry Mountain Reservoir (Veilleux and Reynolds 2006, p. 
330). In Vermont, one summer colony, containing approximately 30 
eastern small-footed bats, was located in a slate roof of a house 
(Darling and Smith 2011, p. 4). Tuttle (1964, p. 149) reported two 
individuals found in April in Tennessee under a large flat rock at the 
edge of a quarry surrounded by woods and cow pastures (elevation 549 m 
(1,800 ft)). In Ontario, a colony of approximately 12 bats was found in 
July behind a shed door (Hitchcock 1955, p. 31). In addition, small 
numbers of adult and juvenile eastern small-footed bats have been 
observed using caves and mines as roosting habitat during the summer 
months in Maryland, Pennsylvania, Kentucky, Arkansas, West Virginia, 
and Virginia (Davis et al. 1965, p. 683; Krutzsch 1966, p. 121; Hall 
and Brenner 1968, p. 779; McDaniel et al. 1982, p. 93; Agosta et al. 
2005, p. 1213; Reynolds, pers. comm.).
    Summer foraging habitat used by eastern small-footed bats includes 
rivers, streams, riparian forests, upland forests, clearings, strip 
mines, and ridgetops (Chenger 2003, pp. 14-23; Chenger 2008a, pp. 10 
and 69-71; Chenger 2008b, p. 6; Hauser and Chenger 2010; Johnson et al. 
2009, p. 3; Mumma and Capouillez 2011, p. 24; Brack et al., unpublished 
manuscript).
Biology
Hibernation
    Eastern small-footed bats hibernate during the winter months to 
conserve energy from increased thermoregulatory demands and reduced 
food resources. To increase energy savings, individuals enter a state 
of torpor where internal body temperatures approach ambient 
temperature, metabolic rates are significantly lowered, and immune 
function declines (Thomas et al. 1990, p. 475; Thomas and Geiser 1997, 
p. 585; Bouma et al. 2010, p. 623). Periodic arousal from torpor 
naturally occurs in all hibernating mammals (Lyman et al. 1982, p. 92), 
although arousals remain among the least understood of hibernation 
phenomena (Thomas and Geiser 1997, p. 585). Numerous factors (e.g., 
reduction of metabolic waste, body temperature theories, and water 
balance theory) have been proposed to account for the occurrence and 
frequency of arousals (Thomas and Geiser 1997, p. 585). Each time a bat 
arouses from torpor, it uses a significant amount of energy to warm its 
body and increase its metabolic rate. The cost and number of arousals 
are the two key factors that determine energy expenditures of 
hibernating bats in winter (Thomas et al. 1990, p. 475). For example, 
little brown bats (Myotis lucifugus) used as much fat during a typical 
arousal from hibernation as would be used during 68 days of torpor, and 
arousals and subsequent activity may constitute 84 percent of the total 
energy used by hibernating bats during the winter (Thomas et al. 1990, 
pp. 477-478).
    Of all hibernating bats, eastern small-footed bats are among the 
last to enter hibernacula and the first to emerge in the spring 
(Barbour and Davis 1969, p. 104). Hibernation is approximately mid-
November to March (Barbour and Davis 1969, p. 104; Dalton 1987, p. 
373); however, there are indications that eastern small-footed bats are 
active during mild winter weather (Mohr 1936, p. 64; Fenton 1972, p. 
5). Fenton (1972, p. 5) observed that when temperatures at hibernation 
sites rose above 4[deg]

[[Page 61050]]

Celsius (C) (39.2 [deg]F (F)), eastern small-footed bats, along with 
big brown bats, aroused and departed from caves and mines. Whether 
these bats departed to take advantage of prey availability during mild 
winter spells or seek out other hibernation sites was never determined. 
Frequent oscillations in microclimate near cave or mine entrances may 
contribute to frequent arousals from torpor by eastern small-footed 
bats (Hitchcock 1965, p. 8). Frequent arousals may deplete energy 
reserves at a faster rate than would more continuous torpor 
characteristic of other cave-hibernating bats, contributing to a lower 
survival rate compared to other Myotis bats (Hitchcock et al. 1984, p. 
129). Eastern small-footed bats lose up to 16 percent of their body 
weights during hibernation (Fenton 1972, p. 5).
    Eastern small-footed bats often hibernate solitarily or in small 
groups and have been found hibernating in the open, in small cracks in 
cave walls and ceilings, in rock crevices in cave or mine floors, and 
beneath rocks (Hitchcock 1949, p. 53; Davis 1955, p. 130; Martin et al. 
1966, p. 349; Barbour and Davis 1969, p. 104; Banfield 1974, p. 52; 
Dalton 1987, p. 373). Martin et al. (1966, p. 349) observed up to 30 
eastern small-footed bats hanging from the ceilings of two mines in New 
York. From one small fissure, Hitchcock (1949, p. 53) extracted 35 
eastern small-footed bats that were packed so tightly that it appeared 
almost impossible for those farthest in to get air. This propensity for 
hibernating in narrow cracks and crevices may mean they are sometimes 
overlooked by surveyors. In Maryland, for example, far fewer eastern 
small-footed bats were observed by surveyors during internal 
hibernacula surveys than were caught in traps during spring emergence 
(Maryland Department of Natural Resources 2011, unpublished data).
    Eastern small-footed bats have been observed hibernating in caves 
that also contain little brown bats, big brown bats, northern long-
eared bats (Myotis septentrionalis), Indiana bats (Myotis sodalis), 
tri-colored bats (Perimyotis subflavus), Virginia big-eared bats 
(Corynorhinus townsendii virginianus), gray bats (Myotis grisescens), 
and Rafinesque's big-eared bats (Corynorhinus rafinesquii rafinesquii), 
and approximately equal numbers of males and females occupy the same 
areas and cluster together indiscriminately (Hitchcock 1949, pp. 48-49; 
Hitchcock 1965, pp. 6-8; Fenton 1972, p. 3; Best and Jennings 1997, p. 
3; Hemberger 2011, unpublished data; Graeter 2011, unpublished data; 
Graham 2011, unpublished data). Fenton (1972, p. 5) commonly observed 
eastern small-footed bats hibernating in physical contact with big 
brown bats, usually in small clusters of fewer than five bats, but 
never close to or in contact with little brown or Indiana bats. Eastern 
small-footed bats often hibernate in a horizontal position, tucked 
between cracks and crevices, unlike most Myotis bats, which hang in the 
open (Merritt 1987, p. 95). When suspended, however, the position of 
the forearm is unique in that, instead of hanging parallel to the body, 
as in other Myotis bats, the forearms are somewhat extended (Banfield 
1974, p. 52). Like most bat species, eastern small-footed bats exhibit 
high site fidelity to hibernacula, with individuals returning to the 
same site year after year (Gates et al. 1984, p. 166).
Migration and Homing
    Eastern small-footed bats have been observed migrating up to 19 
kilometers (km) (12 miles (mi)) (Hitchcock 1955, p. 31) and as little 
as 0.1 km (0.06 mi) from winter hibernacula to summer roost sites 
(Johnson and Gates 2008, p. 456). The distance traveled is probably 
influenced by the availability of hibernacula and roosting sites across 
the landscape (Johnson and Gates 2008, p. 457). But in general, data 
suggest that this species hibernates in proximity to its summer range 
(van Zyll de Jong 1985, p. 119; Divoll et al. 2011). Eastern small-
footed bats show a definite homing ability (Best and Jennings 1997, p. 
4). Marked bats were present in the same cave in consecutive winters, 
and when moved to a different cave during the winter, they returned to 
the original cave the following winter (Mohr 1936, p. 64). In the 
Mammoth Cave region of Kentucky, eastern small-footed bats are fairly 
common in late summer in the groups of migrating bats, although the 
whereabouts of these bats at other seasons is unknown (Barbour and 
Davis 1969, p. 104).
Summer Roosts
    Both males and females change summer roost sites often, even daily, 
although they typically are moving short distances within a general 
area (Chenger 2003, pp. 14-23; Johnson et al. 2011, p. 100; Brack et 
al., unpublished manuscript). Chenger (2009, p. 7) suggests that 
eastern small-footed bats roost in low numbers over a wide area, such 
as talus fields, as a predator-avoidance strategy (Chenger 2009, p. 7). 
Frequent roost-switching may be another means of avoiding potential 
predators. Johnson et al. 2011 (pp. 98-101) radiotracked five lactating 
female bats and five nonreproductive males and observed that females 
and males switched roosts on average every 1.1 days. Males traveled an 
average of 41 m (135 ft) between consecutive roosts. Females traveled 
an average of 67 m (218 ft) between consecutive roosts, and roosts were 
closer to ephemeral water sources than those used by males.
    Johnson et al. 2011 (p. 103) hypothesized that roost selection is 
based on either avoiding detection by predators or minimizing energy 
expenditures. They observed that roosts were located within 15 m (50 
ft) from vegetation or forest edge and in areas with low canopy cover, 
which consequently provided a short distance to protective cover and 
high solar exposure. It appears eastern small-footed bats exhibit 
fidelity to their summer roosting areas, as demonstrated by the 
recapture of banded bats in successive years at the Surry Mountain 
Reservoir and Acadia National Park (Divoll et al. 2013; Veilleux and 
Moosman, unpublished data).
Reproduction
    Available data regarding the eastern small-footed bat suggest that 
females of this species form small summer colonies, with males roosting 
singly or in small groups (Erdle and Hobson 2001, p. 10; Johnson et al. 
2011, p. 100). Small maternity colonies of 12 to 20 individuals 
occurring in buildings have been reported (Merritt 1987, p. 95). 
Eastern small-footed bats are thought to be similar to sympatric Myotis 
that breed in the fall; spermatozoa are stored in the uterus of 
hibernating females until spring ovulation, and a single pup is born in 
May or June (Barbour and Davis 1969, p. 104; Amelon and Burhans 2006, 
p. 58). Brack et al. (unpublished manuscript) captured two female 
eastern small-footed bats in the fall that appeared to have recently 
mated as noted by fluids around the vagina. Two female eastern small-
footed bats caught on June 20 and 24 were pregnant, and 16 female bats 
caught from June 23 to July 15 were lactating (Brack et al., 
unpublished manuscript).
    Adult longevity is estimated to be up to 12 years in the wild 
(Hitchcock 1965, p. 11). Estimated mean annual survival is low compared 
to other Myotis, and survival rates are significantly lower for females 
than for males, 42 and 75 percent, respectively (Hitchcock et al. 1984, 
p. 128). The lower rate of survival of females may be a result of a 
combination of factors: The greater demands of reproduction on females; 
the higher metabolic rates and less frequent torpor; and the greater 
exposure to possible disease-carrying parasites in maternity colonies

[[Page 61051]]

(Hitchcock et al. 1984, p. 127). Low survivorship in combination with 
low reproductive potential (i.e., one offspring produced per year) 
(Best and Jennings 1997, p. 2) may explain why eastern small-footed 
bats are generally uncommon (Hitchcock et al. 1984, p. 129).
Foraging Behavior and Home Range
    Eastern small-footed bats have low wing loading and high, 
frequency-modulated echolocation calls, making them capable of foraging 
efficiently in cluttered forest interiors (Johnson et al. 2009, p. 5). 
Although some accounts state that this species emerges early in the 
evening (van Zyll de Jong 1985, p. 119), Brack et al. (unpublished 
manuscript) found that activity peaked well after dark, and low post-
midnight activities point to the possibility of a bimodal activity 
period. Most observations indicate that eastern small-footed bats fly 
slow and close to the ground, usually at heights from 0.6 to 3.5 m (2 
to 11.5 ft) (Davis et al. 1965, p. 683; Brack et al., unpublished 
manuscript).
    Using ridgelines, streams, and forested roads as travel corridors, 
eastern small-footed bats have been observed travelling from 0.8 to 
13.2 km (0.5 to 8.2 mi) between daytime roost sites and foraging areas 
(Chenger 2003, pp. 14-23; Chenger 2008b, p. 6; Johnson et al. 2009, p. 
3; Mumma and Capouillez 2011, p. 24). Considerable declines in eastern 
small-footed bat capture rates have been observed with increasing 
distance from available rock habitat; and short distances between 
roosts and capture sites suggest these bats have small home ranges 
(Johnson et al. 2011, p. 104). Observed home range varies from 10.2 to 
1,405 hectares (ha) (25 to 3,472 acres (ac)) (Johnson et al. 2009, p. 
3; Mumma and Capouillez 2011, p. 25), although core habitat for three 
male and two female eastern small-footed bats ranged from 4 to 75 ha 
(10 to 185 ac) (50 percent fixed kernel utilization distribution) 
(Mumma and Capouillez 2011, p. 25).
    Food habits of eastern small-footed bats are those of a generalist, 
although moths (Lepidoptera), true flies (Diptera), and beetles 
(Coleoptera) compose most of their diet (Johnson and Gates 2007, p. 
319; Moosman et al. 2007, p. 355; Brack et al., unpublished 
manuscript). Presence of spiders (Araneae) and crickets (Gryllidae) in 
the diet suggest eastern small-footed bats capture some prey via 
gleaning (Moosman et al. 2007, p. 358). Gleaning behavior is 
characterized by catching prey on surfaces via echolocation; calls are 
generally short in duration, high frequency, and of low intensity, 
characteristics that are difficult for some invertebrate prey to detect 
(Faure et al. 1993, p. 174).

Species Information

Northern Long-Eared Bat
Taxonomy and Species Description
    The northern long-eared bat belongs to the order Chiroptera, 
suborder Microchiroptera, family Vespertilionidae, subfamily 
Vesperitilionae, genus Myotis, subgenus Myotis (Caceres and Barclay 
2000, p. 1). The northern long-eared bat was considered a subspecies of 
Keen's long-eared Myotis (Myotis keenii) (Fitch and Schump 1979, p. 1), 
but was recognized as a distinct species by van Zyll de Jong in 1979 
(1979, p. 993) based on geographic separation and difference in 
morphology (as cited in Caceres and Pybus 1997 p. 1; Caceres and 
Barclay 2000, p. 1; Nagorsen and Brigham 1993, p. 87; Whitaker and 
Hamilton 1998, p. 99; Whitaker and Mumford 2009, p. 207; Simmons 2005, 
p. 516). No subspecies have been described for this species (Nagorsen 
and Brigham 1993, p. 90; Whitaker and Mumford 2009, p. 214; van Zyll de 
Jong 1985, p. 94). This species has been recognized by different common 
names, such as: Keen's bat (Whitaker and Hamilton 1998, p. 99), 
northern myotis bat (Nagorsen and Brigham 1993, p. 87, Whitaker and 
Mumford 2009, p. 207), and the northern bat (Foster and Kurta 1999, p. 
660). For the purposes of this finding, we refer to this species as the 
northern long-eared bat, and recognize it as a listable entity under 
the Act.
    A medium-sized bat species, the northern long-eared bat adult body 
weight averages 5 to 8 g (0.2 to 0.3 ounces), with females tending to 
be slightly larger than males (Caceres and Pybus 1997, p. 3). Average 
body length ranges from 77 to 95 mm (3.0 to 3.7 in), tail length 
between 35 and 42 mm (1.3 to 1.6 in), forearm length between 34 and 38 
mm (1.3 to 1.5 in), and wingspread between 228 and 258 mm (8.9 to 10.2 
in) (Caceres and Barclay 2000, p. 1; Barbour and Davis 1969, p. 76). 
Pelage (fur) colors include medium to dark brown on its back, dark 
brown, but not black, ears and wing membranes, and tawny to pale-brown 
fur on the ventral side (Nagorsen and Brigham 1993, p. 87; Whitaker and 
Mumford 2009, p. 207). As indicated by its common name, the northern 
long-eared bat is distinguished from other Myotis species by its long 
ears (average 17 mm (0.7 in), Whitaker and Mumford 2009, p. 207) that, 
when laid forward, extend beyond the nose but less than 5 mm (0.2 in) 
beyond the muzzle (Caceres and Barclay 2000, p. 1). The tragus 
(projection of skin in front of the external ear) is long (average 9 mm 
(0.4 in); Whitaker and Mumford 2009, p. 207), pointed, and symmetrical 
(Nagorsen and Brigham 1993, p. 87; Whitaker and Mumford 2009, p. 207). 
Within its range, the northern long-eared bat can be confused with the 
little brown bat or the western long-eared myotis (Myotis evotis). The 
northern long-eared bat can be distinguished from the little brown bat 
by its longer ears, tragus, slightly longer tail, and less glossy 
pelage (Caceres and Barclay 2000, p. 1). The northern long-eared bat 
can be distinguished from the western long-eared myotis by its darker 
pelage and paler membranes (Caceres and Barclay 2000, p. 1).
Distribution and Abundance
    The northern long-eared bat ranges across much of the eastern and 
north central United States, and all Canadian provinces west to the 
southern Yukon Territory and eastern British Columbia (Nagorsen and 
Brigham 1993, p. 89; Caceres and Pybus 1997, p. 1; Environment Yukon 
2011, p. 10). In the United States, the species' range reaches from 
Maine west to Montana, south to eastern Kansas, eastern Oklahoma, 
Arkansas, and east to the Florida panhandle (Whitaker and Hamilton 
1998, p. 99; Caceres and Barclay 2000, p. 2; Wilson and Reeder 2005, p. 
516; Amelon and Burhans 2006, pp. 71-72). The species' range includes 
the following 39 States (including the District of Columbia, which we 
count as one of the ``States''): Alabama, Arkansas, Connecticut, 
Delaware, the District of Columbia, Florida, Georgia, Illinois, 
Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, 
Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, 
Nebraska, New Hampshire, New Jersey, New York, North Carolina, North 
Dakota, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Carolina, 
South Dakota, Tennessee, Vermont, Virginia, West Virginia, Wisconsin, 
and Wyoming. Historically, the species has been most frequently 
observed in the northeastern United States and in Canadian Provinces, 
Quebec and Ontario, with sightings increasing during swarming and 
hibernation (Caceres and Barclay 2000, p. 2). However, throughout the 
majority of the species' range it is patchily distributed, and 
historically was less common in the southern and western portions of 
the range than in the northern portion of the range (Amelon and Burhans 
2006, p. 71).

[[Page 61052]]

    Although they are typically found in low numbers in inconspicuous 
roosts, most records of northern long-eared bats are from winter 
hibernacula surveys (Caceres and Pybus 1997, p. 2) (for more 
information on use of hibernacula, see Biology below). More than 780 
hibernacula have been identified throughout the species' range in the 
United States, although many hibernacula contain only a few (1 to 3) 
individuals (Whitaker and Hamilton 1998, p. 100). Known hibernacula 
(sites with one or more winter records) include: Arkansas (n=20), 
Connecticut (n=5), Georgia (n=1), Illinois (n=36), Indiana (n=25), 
Kentucky (n=90), Maine (n=3), Maryland (n=11), Massachusetts (n=7), 
Michigan (n=94), Minnesota (n=11), Missouri (n=>111), Nebraska (n=2), 
New Hampshire (n=9), New Jersey (n=8), New York (n=58), North Carolina 
(n=20), Oklahoma (n=4), Ohio (n=3), Pennsylvania (n=112), South 
Carolina (n=2), South Dakota (n=7), Tennessee (n=11), Vermont (n=13 (23 
historical)), Virginia (n=8), West Virginia (n=104), and Wisconsin 
(n=45). Other states within the species' range have no known 
hibernacula (due to no suitable hibernacula present or lack of survey 
effort). They are typically found roosting in small crevices or cracks 
on cave or mine walls or ceilings, thus are easily overlooked during 
surveys and usually observed in small numbers (Griffin 1940, pp. 181-
182; Barbour and Davis 1969, p. 77; Caire et al. 1979, p. 405; Van Zyll 
de Jong 1985, p. 9; Caceres and Pybus 1997, p. 2; Whitaker and Mumford 
2009, pp. 209-210).
    The U.S. portion of the northern long-eared bat's range can be 
described in four parts, as discussed below: the eastern population, 
Midwestern population, the southern population, and the western 
population.

Eastern Population

    Historically, the northern long-eared bat was most abundant in the 
eastern portion its range (Caceres and Barclay 2000, p. 2). Northern 
long-eared bats have been consistently caught during summer mist nets 
surveys and detected during acoustic surveys in eastern populations. 
Large numbers of northern long-eared bats have been found in larger 
hibernacula in Pennsylvania (e.g., an estimated 881 individuals in a 
mine in Bucks County, Pennsylvania in 2004). Fall swarm trapping 
conducted in September-October 1988-1989, 1990-1991, and 1999-2000 at 
two hibernacula with large historical numbers of northern long-eared 
bats had total captures ranging from 6 to 30 bats per hour, which 
demonstrated that the species was abundant at these hibernacula 
(Pennsylvania Game Commission, unpublished data, 2012).
    In Delaware, the species is rare and no hibernacula are documented 
within the State; however, there is a historical record from Newcastle 
County in 1970 (Niederriter 2012, pers. comm.). In Connecticut, the 
northern long-eared bat was historically one of the most commonly 
encountered bats in the State and had been documented statewide 
(Dickson 2011, pers. comm.). In Maine, 3 hibernacula are known (all on 
private land), and the species has also been found in the summer in 
Acadia National Park (DePue 2012, unpublished data) where northern 
long-eared bats were found to be fairly common in 2009-2010 (242 
northern long-eared bats captured comprising 27 percent of the total 
captures for the areas surveyed) (NPS 2010).
    In Maryland, three of seven known hibernacula for the species are 
railroad tunnels, and no summer mist net or acoustic surveys have been 
conducted for the species (Feller 2011, unpublished data). In 
Massachusetts, there are 7 known hibernacula, 42 percent of which are 
privately owned. In New Hampshire, northern long-eared bats are known 
to inhabit at least nine mines and two World War II bunkers and have 
been found in summer surveys, including at Surry Mountain Dam 
(Brunkhurst 2012, unpublished data). In the White Mountain National 
Forest in New Hampshire in 1993-1994, northern long-eared was one of 
the most common species captured (27 percent) (Sasse and Pekins 1996, 
pp. 93-95). In New Jersey, one of the seven known hibernacula is a 
cave, and the remainder are mines (Markuson 2011, unpublished data). 
Northern long-eared bats consisted of 6 to 14 percent of total number 
of captures at Wallkill River National Wildlife Refuge in New Jersey 
from 2006-2010 (Kitchell and Wight 2011).
    In Vermont, prior to 2009, the species was found in 23 hibernacula, 
totaling an estimated 595 animals, which was thought to be an under-
estimate due to the species' preference for hibernating in hibernacula 
cracks and crevices. Summer capture data (2001-2007) indicated that 
northern long-eared bats comprised 19 percent of bats captured; it was 
considered the second most common bat species in the State (Smith 2011, 
unpublished data). In Virginia, they were historically considered 
``fairly common'' during summer mist net surveys; however, they are 
considered ``uncommon'' during winter hibernacula surveys (Reynolds 
2012, unpublished data).
    In West Virginia, northern long-eared bats are found regularly in 
hibernacula surveys, but typically in small numbers (less than 20 
individuals) in caves (Stihler 2012, unpublished data). The species has 
also been found in 41 abandoned coal mines in winter surveys conducted 
from 2002 to 2011 in the New River Gorge National River and Gauley 
River National Recreation Area, both managed by the National Park 
Service (NPS); the largest number observed was 157 in one of the NPS 
mines (NPS 2011, unpublished data). Northern long-eared bats are 
considered common in summer surveys in West Virginia; in summer records 
from 2006-2011 northern long-eared bat captures comprised 46 to 49 
percent of all bat captures (Stihler 2012, pers. comm.).
    Northern long-eared bats have been observed in 58 hibernacula in 
abandoned mines, caves, and tunnels in New York. They have also been 
observed in summer mist net and acoustic surveys. Summer mist-net 
surveys in New York from 2003-2008 resulted in a range of 0.21-0.47 
bats/net night and declined to 0.012 bats/net night in 2011 (Herzog 
2012, unpublished data). They have also been observed on Fort Drum in 
New York, where acoustic surveys (2003-2010) and mist net surveys 
(1999, 2007) have monitored the summer population (Dobony 2011, 
unpublished data). There are no known hibernacula in Rhode Island; 
however, there were 6 records from 2011 mist-net surveys in Washington 
County (Brown 2012, unpublished data).

Midwest Population

    The northern long-eared bat is commonly encountered in summer mist-
net surveys throughout the majority of the Midwest and is considered 
fairly common throughout much of the region. However, the species is 
often found infrequently and in small numbers in hibernacula surveys 
throughout most of the Midwest. In Missouri, northern long-eared bats 
were listed as a State species of conservation concern until 2007, 
after which it was decided the species was more common than previously 
thought because they were commonly captured in mist net surveys (Elliot 
2013, pers. comm.). Historically, the northern long-eared bat was 
considered quite common throughout much of Indiana, and was the fourth 
or fifth most abundant bat species in the State in 2009. The species 
has been captured in at least 51 counties, is often captured in mist-
nets along streams, and is the most common bat taken by trapping at 
mine entrances (Whitaker and Mumford 2009, pp. 207-

[[Page 61053]]

208). The abundance of northern long-eared bats appears to vary within 
Indiana during the summer. For example, during 3 summers (1990-1992) of 
mist-netting surveys in the northern half of Indiana, 37 northern long-
eared bats were captured at 22 of 127 survey sites, which represented 4 
percent of all bats captured (King 1993, p. 10). In contrast, northern 
long-eared bats were the most commonly captured bat species (38 percent 
of all bats captured) during three summers (2006-2008) of mist netting 
on two State forests in south-central Indiana (Sheets et al. 2013, p. 
193). Indiana has 25 hibernacula with winter records of one or more 
northern long-eared bats. However, it is very difficult to find 
individuals in caves and mines during hibernation in large numbers in 
Indiana hibernacula (Whitaker and Mumford 2009, p. 208).
    In Michigan, the northern long-eared bat is known from 25 counties 
and is not commonly encountered in the State except in parts of the 
northern Lower Peninsula and portions of the Upper Peninsula (Kurta 
1982, p. 301; Kurta 2013, pers. comm.). The majority of hibernacula in 
Michigan are in the far northern and western Upper Peninsula; 
therefore, there are very few cave-hibernating bats in general in the 
southern half of the Lower Peninsula during the summer because the 
distance to hibernacula is too great (Kurta 2013, pers. comm.). It is 
thought that the few bats that do spend the summer in the southern half 
of the Lower Peninsula may hibernate in caves or mines in neighboring 
states, such as Indiana (Kurta 1982, pp. 301-302; Kurta 2013, pers. 
comm.).
    In Wisconsin, the species is reported to be uncommon (Amelon and 
Burhans 2006, pp. 71-72). ``Although the northern long-eared bat can be 
found in many parts of Wisconsin, it is clearly not abundant in any one 
location. The department has determined that the Northern long-eared 
bat is one of the least abundant bats in Wisconsin through cave and 
mine hibernacula counts, acoustic surveys, mist-netting in summer 
foraging areas and harp trap captures during the fall swarming period'' 
(Redell 2011, pers. comm.). Northern long-eared bats are regularly 
caught in mist-net surveys in the Shawnee National Forest in southern 
Illinois (Kath 2013, pers. comm.). Further, the average number of 
northern long-eared bats caught during surveys between 1999 and 2011 at 
Oakwood Bottoms in the Shawnee National Forest has been fairly 
consistent (Carter 2012, pers. comm.). In Iowa, there are only summer 
mist net records for the species; in 2011 there were eight records 
(including three lactating females) from west-central Iowa (Howell 
2011, unpublished data). In Minnesota, one mine in St. Louis County may 
contain a large number of individuals, possibly over 3,000; however, 
this is a very rough estimate since the majority of the mine cannot be 
safely accessed for surveys (Nordquist 2012, pers. comm.). In Ohio, 
there are three known hibernacula and the largest population in Preble 
County has had more than 300 bats. In general, northern long-eared bats 
are also regularly collected as incidental catches in mist-net surveys 
for Indiana bats in Ohio (Boyer 2012, pers. comm.).

Southern Population

    The northern long-eared bat is less common in the southern portion 
of its range than in the northern portion of the range (Amelon and 
Burhans 2006, p. 71) and, in the South, is considered more common in 
states such as Kentucky and Tennessee, and more rare in the southern 
extremes of the range (e.g., Alabama, Georgia, South Carolina). In 
Alabama, the northern long-eared bat is rare, while in Tennessee it is 
uncommon (Amelon and Burhans 2006, pp. 71-72). In Tennessee, northern 
long-eared bats were found in summer mist-net surveys conducted through 
summer of 2010 in addition to hibernacula censuses. Northern long-eared 
bats were found in 11 caves surveyed in 2011 in Tennessee (Pelren 2011, 
pers. comm.). In 2000, during sampling of bat populations in the 
Kisatchie National Forest, Louisiana, three northern long-eared bat 
specimens were collected; these were the first official records of the 
species from Louisiana (Crnkovic 2003, p. 715). In Georgia, northern 
long-eared bats have been found at 1 of 5 known hibernacula in the 
State and 24 summer records were found between 2007 and 2011. Mist-net 
surveys were conducted in the Chattahoochee National Forest in 2001-
2002 and 2006-2007, with 51 total records for the species (Morris 2012, 
unpublished data). Northern long-eared bats have been found in 20 
hibernacula within North Carolina (Graeter 2011, unpublished data). In 
the summer of 2007, (Morris et al. 2009, p. 356) six northern long-
eared bats were captured in Washington County, North Carolina. Both 
adults and juveniles were captured, suggesting that there is a 
reproducing resident population (Morris et al. 2009, p. 359). In 
Kentucky, although typically found in small numbers, northern long-
eared bats were historically found in the majority of hibernacula in 
Kentucky and have been a commonly captured species during summer 
surveys (Hemberger 2012, pers. comm.). The northern long-eared bat can 
be found throughout the majority of Kentucky, with historical records 
in 91 of its 120 counties. Eighty-five counties have summer records, 
and 68 of those include reproductive records (i.e., captures of 
juveniles or pregnant, lactating, or post-lactating adult females) 
(Hemberger 2012, pers. comm.). In South Carolina, there are two known 
hibernacula: one is a cave that had 26 bats present in 1995, but has 
not been surveyed since, and the other is a tunnel where only one bat 
was found in 2011 (Bunch 2011, unpublished data). Northern long-eared 
bats are known from 20 hibernacula in Arkansas, although they are 
typically found in very low numbers (Sasse 2012, unpublished data). 
Surveys in the Ouachita Mountains of central Arkansas from 2000-2005 
tracked 17 males and 23 females to 43 and 49 day roosts, respectively 
(Perry and Thill 2007, pp. 221-222). The northern long-eared bat is 
known to occur in seven counties along the eastern edge of Oklahoma, 
(Stevenson 1986, p. 41). The species has been recorded in 21 caves (7 
of which occur on the Ozark Plateau National Wildlife Refuge) during 
the summer. The species has regularly been captured in summer mist-net 
surveys at cave entrances in Adair, Cherokee, Sequoyah, Delaware, and 
LeFlore counties, and are often one of the most common bats captured 
during mist-net surveys at cave entrances in the Ozarks of northeastern 
Oklahoma (Stark 2013, pers. comm.). Small numbers of northern long-
eared bats (typical range of 1-17 individuals) also have been captured 
during mist-net surveys along creeks and riparian zones in eastern 
Oklahoma.

Western Population

    The northern long-eared bat is generally less common in the western 
portion of its range than in the northern portion of the range (Amelon 
and Burhans 2006, p. 71) and is considered common in only small 
portions of the western part of its range (e.g., Black Hills of South 
Dakota) and uncommon or rare in the western extremes of the range 
(e.g., Wyoming, Kansas, Nebraska) (Caceres and Barclay 2000, p. 2). The 
northern long-eared bat has been observed hibernating and residing 
during the summer and is considered abundant in the Black Hills 
National Forest in South Dakota. Capture and banding data for survey 
efforts in the Black Hills of South Dakota and Wyoming showed northern 
long-eared bats to be the second most common bat banded (159 of 878 
total bats) during 3 years of survey effort (Tigner and Aney

[[Page 61054]]

1994, p. 4). South Dakota contains seven known hibernacula, five of 
which are abandoned mines. The largest number of individuals was found 
in a hibernaculum near Hill City, South Dakota; 40 individuals were 
found in this mine in the winter of 2002-2003 (Tigner and Stukel 2003, 
pp. 27-28). A summer population was found on the habitats in Dakota 
Prairie National Grassland and Custer National Forest in 2005 (Lausen 
undated, unpublished data). Also, northern long-eared bats have been 
captured during the summer along the Missouri River in South Dakota 
(Swier 2006, p. 5; Kiesow and Kiesow 2010, pp. 65-66). Summer surveys 
in North Dakota (2009-2011) documented the species in the Turtle 
Mountains, the Missouri River Valley, and in the Badlands (Gillam and 
Barnhart 2011, pp. 10-12). No hibernacula are known within North 
Dakota; however, there has been very limited survey effort in the State 
(Riddle 2012, pers. comm.).
    Northern long-eared bats have been observed at two quarries located 
in east-central Nebraska, but there is no survey data for either of 
these sites (Geluso 2011, unpublished data). They are also known to 
summer in the northwestern parts of Nebraska, specifically Pine Ridge 
in Sheridan County (only males have been documented), and a reproducing 
population has been documented north of Valentine in Cherry County 
(Benedict et al. 2000, pp. 60-61). During an acoustic survey conducted 
during the summer of 2012 the species was common in Cass County (east-
central Nebraska), but was uncommon or absent from extreme southeastern 
Nebraska (White et al. 2012, p. 2). The occurrence of this species in 
Cass County, Nebraska is likely attributable to limestone quarries in 
the region that are used as hibernacula by this species and others 
(White et al. 2012, p. 3).
    During acoustic and mist net surveys conducted throughout Wyoming 
in the summers of 2008-2011, 27 separate observations of northern long-
eared bats were made in the northeast part of the State and breeding 
was confirmed (Wyoming Game and Fish Department 2012, unpublished 
data). To date, there are no known hibernacula in Wyoming and it is 
unclear if there are existing hibernacula, although the majority of 
potential hibernacula (abandoned mines) within the State occur outside 
of the northern long-eared bat's range (Tigner and Stukel 2003, p. 27; 
Wyoming Game and Fish Department 2012). Montana has only one known 
record: a male collected in an abandoned coal mine in 1978 in Richland 
County (Montana Fish, Wildlife, and Parks 2012). In Kansas, the 
northern long-eared bat was first found in summer mist-net surveys in 
1994 and 1995 in Osborne and Russell counties, before which the species 
was thought to only migrate through parts of the State (Sparks and 
Choate 1995, p. 190).

Canada Population

    The northern long-eared bat occurs throughout the majority of the 
forested regions of Canada, although it is found in higher abundance in 
eastern Canada than in western Canada, similar to in the United States 
(Caceres Pybus 1997, p. 6). However, the scarcity of records in the 
western parts of Canada may be due to more limited survey efforts. It 
has been estimated that approximately 40 percent of the northern long-
eared bat's global range is in Canada; however, due to the species 
being relatively common and widespread, limited effort has been made to 
determine overall population size within Canada (COSEWIC 2012, p.9). 
The range of the northern long-eared bat in Canada includes Alberta, 
British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, 
Northwest Territories, Nova Scotia, Prince Edward Island, Ontario, 
Quebec, Saskatchewan, and Yukon (COSEWIC 2012, p. 4). There are no 
records of the species overwintering in Yukon and Northwest Territories 
(COSEWIC 2012, p. 9).
Habitat
Winter Habitat
    Northern long-eared bats predominantly overwinter in hibernacula 
that include caves and abandoned mines. Hibernacula used by northern 
long-eared bats are typically large, with large passages and entrances 
(Raesly and Gates 1987, p. 118), relatively constant, cooler 
temperatures (0 to 9 [deg]C (32 to 48 [deg]F) (Raesly and Gates 1987, 
p. 18; Caceres and Pybus 1997, p. 2; Brack 2007, p. 744), and with high 
humidity and no air currents (Fitch and Shump 1979, p. 2; Van Zyll de 
Jong 1985, p. 94; Raesly and Gates 1987 p. 118; Caceres and Pybus 1997, 
p. 2). The sites favored by northern long-eared bats are often in very 
high humidity areas, to such a large degree that droplets of water are 
often observed on their fur (Hitchcock 1949, p. 52; Barbour and Davis 
1969, p. 77). Northern long-eared bats typically prefer cooler and more 
humid conditions than little brown bats, similar to the eastern small-
footed bat and big brown bat, although the latter two species tolerate 
lower humidity than northern long-eared bats (Hitchcock 1949, p. 52-53; 
Barbour and Davis 1969, p. 77; Caceres and Pybus 1997, p. 2). Northern 
long-eared bats are typically found roosting in small crevices or 
cracks in cave or mine walls or ceilings, often with only the nose and 
ears visible, thus are easily overlooked during surveys (Griffin 1940, 
pp. 181-182; Barbour and Davis 1969 p.77; Caire et al. 1979, p. 405; 
Van Zyll de Jong 1985, p.9; Caceres and Pybus 1997, p. 2; Whitaker and 
Mumford 2009, pp. 209-210). Caire et al. (1979, p. 405) and Whitaker 
and Mumford (2009, p. 208) commonly observed individuals exiting caves 
with mud and clay on their fur, also suggesting the bats were roosting 
in tighter recesses of hibernacula. They are also found hanging in the 
open, although not as frequently as in cracks and crevices (Barbour and 
Davis 1969, p.77, Whitaker and Mumford 2009, pp. 209-210). In 1968, 
Whitaker and Mumford (2009, pp. 209-210) observed three northern long-
eared bats roosting in the hollow core of stalactites in a small cave 
in Jennings County, Indiana.
    To a lesser extent, northern long-eared bats have been found 
overwintering in other types of habitat that resemble cave or mine 
hibernacula, including abandoned railroad tunnels, more frequently in 
the northeast portion of the range. Also, in 1952 three northern long-
eared bats were found hibernating near the entrance of a storm sewer in 
central Minnesota (Goehring 1954, p. 435). Kurta and Teramino (1994, 
pp. 410-411) found northern long-eared bats hibernating in a hydro-
electric dam facility in Michigan. In Massachusetts, northern long-
eared bats have been found hibernating in the Sudbury Aqueduct, a 
structure created in the late 1800s to transfer water, but that is 
rarely used for this purpose today (French 2012, unpublished data). 
Griffin (1945, p. 22) found northern long-eared bats in December in 
Massachusetts in a dry well, and commented that these bats may 
regularly hibernate in ``unsuspected retreats'' in areas where caves or 
mines are not present.
Summer Habitat
    During the summer, northern long-eared bats typically roost singly 
or in colonies underneath bark or in cavities or crevices of both live 
trees and snags (Sasse and Perkins 1996, p. 95; Foster and Kurta 1999, 
p. 662; Owen et al. 2002, p. 2; Carter and Feldhamer 2005, p. 262; 
Perry and Thill 2007, p. 222; Timpone et al. 2010, p. 119). Males and 
non-reproductive females' summer roost sites may also include cooler 
locations, including caves and mines (Barbour and Davis 1969, p. 77; 
Amelon and Burhans 2006, p. 72). Northern long-eared bats have also 
been observed roosting in

[[Page 61055]]

colonies in humanmade structures, such as buildings, barns, a park 
pavilion, sheds, cabins, under eaves of buildings, behind window 
shutters, and in bat houses (Mumford and Cope 1964, p. 72; Barbour and 
Davis 1969, p. 77; Cope and Humphrey 1972, p. 9 ; Amelon and Burhans 
2006, p. 72; Whitaker and Mumford 2009, p. 209; Timpone et al. 2010, p. 
119; Joe Kath 2013, pers. comm.).
    The northern long-eared bat appears to be somewhat opportunistic in 
tree roost selection, selecting varying roost tree species and types of 
roosts throughout its range, including tree species such as black oak 
(Quercus velutina), northern red oak (Quercus rubra), silver maple 
(Acer saccharinum), black locust (Robinia pseudoacacia), American beech 
(Fagus grandifolia), sugar maple (Acer saccharum), sourwood (Oxydendrum 
arboreum), and shortleaf pine (Pinus echinata) (e.g., Mumford and Cope 
1964, p. 72; Clark et al. 1987, p. 89; Sasse and Pekins 1996, p. 95; 
Foster and Kurta 1999, p. 662; Lacki and Schwierjohann 2001, p. 484; 
Owen et al. 2002, p. 2; Carter and Feldhamer 2005, p. 262; Perry and 
Thill 2007, p. 224; Timpone et al. 2010, p. 119). Northern long-eared 
bats most likely are not dependent on a certain species of trees for 
roosts throughout their range; rather, certain tree species will form 
suitable cavities or retain bark and the bats will use them 
opportunistically (Foster and Kurta 1999, p. 668). Carter and Felhamer 
(2005, p. 265) speculated that structural complexity of habitat or 
available roosting resources are more important factors than the actual 
tree species.
    Many studies have documented the northern long-eared bat's 
selection of live trees and snags, with a range of 10 to 53 percent 
selection of live roosts found (Sasse and Perkins 1996, p. 95; Foster 
and Kurta 1999, p. 668; Lacki and Schwierjohann 2001, p. 484; Menzel et 
al. 2002, p. 107; Carter and Feldhamer 2005, p. 262; Perry and Thill 
2007, p. 224; Timpone et al. 2010, p. 118). Foster and Kurta (1999, p. 
663) found 53 percent of roosts in Michigan were in living trees, 
whereas in New Hampshire, 34 percent of roosts were in snags (Sasse and 
Pekins 1996, p. 95). The use of live trees versus snags may reflect the 
availability of such structures in study areas (Perry and Thill 2007, 
p. 224) and the flexibility in roost selection when there is a 
sympatric bat species present (e.g., Indiana bat) (Timpone et al. 2010, 
p. 120). In tree roosts, northern long-eared bats are typically found 
beneath loose bark or within cavities and have been found to use both 
exfoliating bark and crevices to a similar degree for summer roosting 
habitat (Foster and Kurta 1999, p. 662; Lacki and Schwierjohann 2001, 
p. 484; Menzel et al. 2002, p. 110; Owen et al. 2002, p. 2; Perry and 
Thill 2007, p. 222; Timpone et al. 2010, p. 119).
    Canopy coverage at northern long-eared bat roosts has ranged from 
56 percent in Missouri (Timone et al. 2010, p. 118), 66 percent in 
Arkansas (Perry and Thill 2007, p. 223), greater than 75 percent in New 
Hampshire (Sasse and Pekins 1996, p. 95), to greater than 84 percent in 
Kentucky (Lacki and Schwierjohann 2001, p. 487). Studies in New 
Hampshire and British Columbia have found that canopy coverage around 
roosts is lower than in available stands (Caceres 1998; Sasse and 
Pekins 1996, p. 95). Females tend to roost in more open areas than 
males, likely due to the increased solar radiation, which aids pup 
development (Perry and Thill 2007, p. 224). Fewer trees surrounding 
maternity roosts may also benefit juvenile bats that are starting to 
learn to fly (Perry and Thill 2007, p. 224). However, in southern 
Illinois, northern long-eared bats were observed roosting in areas with 
greater canopy cover than in random plots (Carter and Feldhamer 2005, 
p. 263). Roosts are also largely selected below the canopy, which could 
be due to the species' ability to exploit roosts in cluttered 
environments; their gleaning behavior suggests an ability to easily 
maneuver around obstacles (Foster and Kurta 1999, p. 669; Menzel et al. 
2002, p. 112).
    Female northern long-eared bats typically roost in tall, large-
diameter trees (Sasse and Pekins 1996, p. 95). Studies have found that 
the diameter-at-breast height (dbh) of northern long-eared bat roost 
trees was greater than random trees (Lacki and Schwierjohann 2001, p. 
485) and others have found both dbh and height of selected roost trees 
to be greater than random trees (Sasse and Pekins 1996, p. 97; Owen et 
al. 2002 p. 2). However, other studies have found that roost tree mean 
dbh and height did not differ from random trees (Menzel et al. 2002, p. 
111; Carter and Feldhamer 2005, p. 266). Lacki and Schwierjohann (2001, 
p. 486) have also found that northern long-eared bats roost more often 
on upper and middle slopes than lower slopes, which suggests a 
preference for higher elevations due to increased solar heating.
Biology
Hibernation
    Similar to the eastern small-footed bat description above, the 
northern long-eared bats hibernate during the winter months to conserve 
energy from increased thermoregulatory demands and reduced food 
resources. In general, northern long-eared bats arrive at hibernacula 
in August or September, enter hibernation in October and November, and 
leave the hibernacula in March or April (Caire et al. 1979, p. 405; 
Whitaker and Hamilton 1998, p. 100; Amelon and Burhans 2006, p. 72). 
However, hibernation may begin as early as August (Whitaker and Rissler 
1992, p. 56). In Copperhead Cave in west-central Indiana, the majority 
of bats enter hibernation during October, and spring emergence occurs 
mainly from about the second week of March to mid-April (Whitaker and 
Mumford 2009, p. 210). In Indiana, northern long-eared bats become more 
active and start feeding outside the hibernaculum in mid-March, 
evidenced by stomach and intestine contents. This species also showed 
spring activity earlier than little brown bats and tri-colored bat 
(Whitaker and Rissler 1992, pp. 56-57). In northern latitudes, such as 
in upper Michigan's copper-mining district, hibernation for northern 
long-eared bats and other myotis species may begin as early as late 
August and may last for 8 to 9 months (Stones and Fritz, 1969, p. 81; 
Fitch and Shump 1979, p. 2). Northern long-eared bats have shown a high 
degree of philopatry (using the same site multiple years) for a 
hibernaculum (Pearson 1962, p. 30), although they may not return to the 
same hibernaculum in successive seasons (Caceres and Barclay 2000, p. 
2).
    Typically, northern long-eared bats are not abundant and compose a 
small proportion of the total number of bats hibernating in a 
hibernaculum (Barbour and Davis 1969, p. 77; Mills 1971, p. 625; Caire 
et al. 1979, p. 405; Caceres and Barclay 2000, pp. 2-3). Although 
usually found in small numbers, the species typically inhabits the same 
hibernacula with large numbers of other bat species, and occasionally 
are found in clusters with these other bat species. Other species that 
commonly occupy the same habitat include: little brown bat, big brown 
bat, eastern small-footed bat, tri-colored bat, and Indiana bat 
(Swanson and Evans 1936, p. 39; Griffin 1940, p. 181; Hitchcock 1949, 
pp. 47-58; Stones and Fritz 1969, p. 79; Fitch and Shump 1979, p. 2). 
Whitaker and Mumford (2009, pp. 209-210), however, infrequently found 
northern long-eared bats hibernating beside little brown bats, Indiana 
bats, or tri-colored bats, since they found few hanging on side walls 
or ceilings of cave passages. Barbour and Davis (1969, p. 77) found 
that the

[[Page 61056]]

species is never abundant and rarely recorded in concentrations of over 
100 in a single hibernaculum.
    Northern long-eared bats often move between hibernacula throughout 
the winter, which may further decrease population estimates (Griffin 
1940, p. 185; Whitaker and Rissler 1992b, p. 131; Caceres and Barclay 
2000 pp. 2-3). Whitaker and Mumford (2009, p. 210) found that this 
species flies in and out of some of the mines and caves in southern 
Indiana throughout the winter. In particular, the bats were active at 
Copperhead Cave periodically all winter, with northern long-eared bats 
being more active than other species (such as little brown bat and tri-
colored bat) hibernating in the cave. Though northern long-eared bats 
fly outside of the hibernacula during the winter, they do not feed; 
hence the function of this behavior is not well understood (Whitaker 
and Hamilton 1998, p. 101). However, it has been suggested that bat 
activity during winter could be due in part to disturbance by 
researchers (Whitaker and Mumford 2009, pp. 210-211).
    Northern long-eared bats exhibited significant weight loss during 
hibernation. In southern Illinois, weight loss during hibernation was 
found in male northern long-eared bats, with individuals weighing an 
average of 6.6 g (0.2 ounces) prior to 10 January, and those collected 
after that date weighing an average of 5.3 g (0.2 ounces) (Pearson 
1962, p. 30). Whitaker and Hamilton (1998, p. 101) reported a weight 
loss of 41-43 percent over the hibernation period for northern long-
eared bats in Indiana. In eastern Missouri, male northern long-eared 
bats lost an average of 3 g (0.1 ounces) during the hibernation period 
(late October through March), and females lost an average of 2.7 g (0.1 
ounces) (Caire et al. 1979, p. 406).
Migration and Homing
    While the northern long-eared bat is not considered a long-distance 
migratory species, short migratory movements between summer roost and 
winter hibernacula between 56 km (35 mi) and 89 km (55 mi) have been 
documented (Nagorsen and Brigham 1993 p. 88; Griffith 1945, p. 53). 
However, movements from hibernacula to summer colonies may range from 8 
to 270 km (5 to 168 mi) (Griffin 1945, p. 22).
    Several studies show a strong homing ability of northern long-eared 
bats in terms of return rates to a specific hibernaculum, although bats 
may not return to the same hibernaculum in successive winters (Caceres 
and Barclay 2000, p. 2). Banding studies in Ohio, Missouri, and 
Connecticut show return rates to hibernacula of 5.0 percent (Mills 
1971, p. 625), 4.6 percent (Caire et al. 1979, p. 404), and 36 percent 
(Griffin 1940, p. 185), respectively. An experiment showed an 
individual bat returned to its home cave up to 32 km (20 mi) away after 
being removed 3 days prior (Stones and Branick 1969, p. 158). 
Individuals have been known to travel between 56 and 97 km (35 and 60 
mi) between caves during the spring (Caire et al. 1979, p. 404; Griffin 
1945, p. 20).
Summer Roosts
    Northern long-eared bats switch roosts often (Sasse and Perkins 
1996, p. 95), typically every 2-3 days (Foster and Kurta 1999, p. 665; 
Owen et al. 2002, p. 2; Carter and Feldhamer 2005, p. 261; Timpone et 
al. 2010, p. 119). In Missouri, the longest time spent roosting in one 
tree was 3 nights; however, the up to 11 nights spent roosting in a 
humanmade structure has been documented (Timpone et al. 2010, p. 118). 
Similarly, Carter and Feldhamer (2005, p. 261) found that the longest a 
northern long-eared bat used the same tree was 3 days; in West 
Virginia, the average time spent at one roost was 5.3 days (Menzel et 
al. 2002, p. 110). Bats switch roosts for a variety of reasons, 
including, temperature, precipitation, predation, parasitism, and 
ephemeral roost sites (Carter and Feldhamer 2005, p. 264). Ephemeral 
roost sites, with the need to proactively investigate new potential 
roost trees prior to their current roost tree becoming uninhabitable 
(e.g., tree falls over), may be the most likely scenario (Kurta et al. 
2002, p. 127; Carter and Feldhamer 2005, p. 264; Timpone et al. 2010, 
p. 119). In Missouri, Timpone et al. (2010, p. 118) radiotracked 13 
northern long-eared bats to 39 roosts and found the mean distance 
between the location where captured and roost tree was 1.7 km (1.1 mi) 
(range 0.07-4.8 km (0.04-3.0 mi), and the mean distance traveled 
between roost trees was 0.67 km (0.42 mi) (range 0.05-3.9 km (0.03-2.4 
mi)). In Michigan, the longest distance the same bat moved between 
roosts was 2 km (1.2 mi) and the shortest was 6 m (20 ft) (Foster and 
Kurta 1999, p. 665). In New Hampshire, the mean distance between 
foraging areas and roost trees was 602 m (1975 ft) (Sasse and Pekins 
1996, p. 95). In the Ouachita Mountains of Arkansas, Perry and Thill 
(2007, p. 22) found that individuals moved among snags that were within 
less than 2 ha (5 ac).
    Some studies have found tree roost selection to differ slightly 
between male and female northern long-eared bats. Male northern long-
eared bats have been found to more readily use smaller diameter trees 
for roosting than females, suggesting males are more flexible in roost 
selection than females (Lacki and Schwierjohann 2001, p. 487; Broders 
and Forbes 2004, p. 606; Perry and Thill 2007, p. 224). In the Ouachita 
Mountains of Arkansas, both sexes primarily roosted in snags, although 
females roosted in snags surrounded by fewer midstory trees than did 
males (Perry and Thill 2007, p. 224). In New Brunswick, Canada, Broders 
and Forbes (2004, pp. 606-607) found that there was spatial segregation 
between male and female roosts, with female maternity colonies 
typically occupying more mature, shade-tolerant deciduous tree stands 
and males occupying more conifer-dominated stands. In northeastern 
Kentucky, males do not use colony roosting sites and are typically 
found occupying cavities in live hardwood trees, while females form 
colonies more often in both hardwood and softwood snags (Lacki and 
Schwierjohann 2001, p. 486).
    The northern long-eared bat is comparable to the Indiana bat in 
terms of summer roost selection, but appears to be more opportunistic 
(Carter and Feldhamer 2005, pp. 265-266; Timpone et al. 2010, p. 120-
121). In southern Michigan, northern long-eared bats used cavities 
within roost trees, living trees, and roosts with greater canopy cover 
more often than does the Indiana bat, which occurred in the same area 
(Foster and Kurta 1999, p. 670). Similarly, in northeastern Missouri, 
Indiana bats typically roosted in snags with exfoliating bark and low 
canopy cover, whereas northern long-eared bats used the same habitat in 
addition to live trees, shorter trees, and trees with higher canopy 
cover (Timpone et al. 2010 pp. 118-120). Although northern long-eared 
bats are more opportunistic than Indiana bats, there may be a small 
amount of roost selection overlap between the two species (Foster and 
Kurta 1999, p. 670; Timpone et al. 2010, pp. 120-121).
Reproduction
    Breeding occurs from late July in northern regions to early October 
in southern regions and commences when males begin to swarm hibernacula 
and initiate copulation activity (Whitaker and Hamilton 1998, p. 101; 
Whitaker and Mumford 2009, p. 210; Caceres and Barclay 2000, p. 2; 
Amelon and Burhans 2006, p. 69). Copulation occasionally occurs again 
in the spring (Racey 1982, p. 73). Hibernating females store sperm 
until spring, exhibiting a delayed fertilization strategy (Racey 1979, 
p.

[[Page 61057]]

392; Caceres and Pybus 1997, p. 4). Ovulation takes place at the time 
of emergence from the hibernaculum, followed by fertilization of a 
single egg, resulting in a single embryo (Cope and Humphrey 1972, p. 9; 
Caceres and Pybus 1997, p. 4; Caceres and Barclay 2000, p. 2); 
gestation is approximately 60 days (Kurta 1994, p. 71). Males are 
reproductively inactive until late July, with testes descending in most 
males during August and September (Caire et al. 1979, p. 407; Amelon 
and Burhans 2006, p. 69).
    Maternity colonies, consisting of females and young, are generally 
small, numbering from about 30 (Whitaker and Mumford 2009, p. 212) to 
60 individuals (Caceres and Barclay 2000, p. 3); however, one group of 
100 adult females was observed in Vermilion County, Indiana (Whitaker 
and Mumford 2009, p. 212). In West Virginia, maternity colonies in two 
studies had a range of 7-88 individuals (Owen et al. 2002, p. 2) and 
11-65 individuals, with a mean size of 31 (Menzel et al. 2002, p. 110). 
Lacki and Schwierjohann (2001, p. 485) found that the population size 
of colony roosts declined as the summer progressed with pregnant 
females using the largest colonies (mean=26) and post-lactating females 
using the smallest colonies (mean=4), with the largest overall reported 
colony size of 65 bats. Other studies have also found that the number 
of individuals within a maternity colony typically decreases from 
pregnancy to post-lactation (Foster and Kurta 1999, p. 667; Lacki and 
Schwierjohann 2001, p. 485; Garroway and Broders 2007, p. 962; Perry 
and Thill 2007, p. 224; Johnson et al. 2012, p. 227). Female roost site 
selection, in terms of canopy cover and tree height, changes depending 
on reproductive stage; relative to pre- and post-lactation periods, 
lactating northern long-eared bats have been shown to roost higher in 
tall trees situated in areas of relatively less canopy cover and tree 
density (Garroway and Broders 2008, p. 91).
    Adult females give birth to a single pup (Barbour and Davis 1969). 
Birthing within the colony tends to be synchronous, with the majority 
of births occurring around the same time (Krochmal and Sparks 2007, p. 
654). Parturition (birth) likely occurs in late May or early June 
(Caire et al. 1979, p. 406; Easterla 1968, p. 770; Whitaker and Mumford 
2009, p. 213), but may occur as late as July (Whitaker and Mumford 
2009, p. 213). Broders et al. (2006, p. 1177) estimated a parturition 
date of July 20 in New Brunswick. Lactating and post-lactating females 
were observed in mid-June in Missouri (Caire et al. 1979, p. 407), July 
in New Hampshire and Indiana (Sasse and Pekins 1996, p. 95; Whitaker 
and Mumford 2009, p. 213), and August in Nebraska (Benedict 2004, p. 
235). Juvenile volancy (flight) occurs by 21 days after parturition 
(Krochmal and Sparks 2007, p. 651, Kunz 1971, p. 480) and as early as 
18 days after parturition (Krochmal and Sparks 2007, p. 651). Subadults 
were captured in late June in Missouri (Caire et al. 1979, p. 407), 
early July in Iowa (Sasse and Pekins 1996, p. 95), and early August in 
Ohio (Mills 1971, p. 625).
    Adult longevity is estimated to be up to 18.5 years (Hall 1957, p. 
407), with the greatest recorded age of 19 years (Kurta 1995, p. 71). 
Most mortality for northern long-eared and many other species of bats 
occurs during the juvenile stage (Caceres and Pybus 1997, p. 4).
Foraging Behavior and Home Range
    The northern long-eared bat has a diverse diet including moths, 
flies, leafhoppers, caddisflies, and beetles (Nagorsen and Brigham 
1993, p. 88; Brack and Whitaker 2001, p. 207; Griffith and Gates 1985, 
p. 452), with diet composition differing geographically and seasonally 
(Brack and Whitaker 2001, p. 208). Feldhamer et al. (2009, p. 49) noted 
close similarities of all Myotis diets in southern Illinois, while 
Griffith and Gates (1985, p. 454) found significant differences in the 
diets of northern long-eared bat and little brown bat. The most common 
insects found in the diets of northern long-eared bats are 
lepidopterans (moths) and coleopterans (beetles) (Feldhamer et al. 
2009, p. 45; Brack and Whitaker 2001, p. 207) with arachnids (spiders) 
also being a common prey item (Feldhamer et al. 2009, p. 45).
    Foraging techniques include hawking (catching insects in flight) 
and gleaning in conjunction with passive acoustic cues (Nagorsen and 
Brigham 1993, p. 88; Ratcliffe and Dawson 2003, p. 851). Observations 
of northern long-eared bats foraging on arachnids (Feldhamer et al. 
2009, p. 49), presence of green plant material in their feces (Griffith 
and Gates 1985, p. 456), and non-flying prey in their stomach contents 
(Brack and Whitaker 2001, p. 207) suggest considerable gleaning 
behavior. Northern long-eared bats have the highest frequency call of 
any bat species in the Great Lakes area (Kurta 1995, p. 71). Gleaning 
allows this species to gain a foraging advantage for preying upon moths 
because moths are less able to detect these high frequency echolocation 
calls (Faure et al. 1993, p. 185). Emerging at dusk, most hunting 
occurs above the understory, 1 to 3 m (3 to 10 ft) above the ground, 
but under the canopy (Nagorsen and Brigham 1993, p. 88) on forested 
hillsides and ridges, rather than along riparian areas (Brack and 
Whitaker 2001, p. 207; LaVal et al. 1977, p. 594). This coincides with 
data indicating that mature forests are an important habitat type for 
foraging northern long-eared bats (Caceres and Pybus 1998, p. 2). 
Occasional foraging also takes place over forest clearings and water, 
and along roads (Van Zyll de Jong 1985, p. 94). Foraging patterns 
indicate a peak activity period within 5 hours after sunset followed by 
a secondary peak within 8 hours after sunset (Kunz 1973, p. 18-19). 
Brack and Whitaker (2001, p. 207) did not find significant differences 
in the overall diet of northern long-eared bats between morning (3 a.m. 
to dawn) and evening (dusk to midnight) feedings; however there were 
some differences in the consumption of particular prey orders between 
morning and evening feedings. Additionally, no significant differences 
existed in dietary diversity values between age classes or sex groups 
(Brack and Whitaker 2001, p. 208).
    Female home range size may range from 19 to 172 ha (47-425 acres) 
(Lacki et al. 2009, p. 5). Owen et al. (2003, p. 353) estimated average 
maternal home range size to be 65 ha (161 ac). Home range size of 
northern long-eared bats in this study site was small relative to other 
bat species, but this may be due to the study's timing (during the 
maternity period) and the small body size of M. septentrionalis (Owen 
et al. 2003, pp. 354-355). The mean distance between roost trees and 
foraging areas of radio-tagged individuals in New Hampshire was 620 m 
(2034 ft) (Sasse and Pekins 1996, p. 95).

Summary of Factors Affecting the Species

    Section 4 of the Act (16 U.S.C. 1533), and its implementing 
regulations at 50 CFR part 424, set forth the procedures for adding 
species to the Federal Lists of Endangered and Threatened Wildlife and 
Plants. Under section 4(a)(1) of the Act, we may list a species based 
on any of the following five factors: (A) The present or threatened 
destruction, modification, or curtailment of its habitat or range; (B) 
overutilization for commercial, recreational, scientific, or 
educational purposes; (C) disease or predation; (D) the inadequacy of 
existing regulatory mechanisms; and (E) other natural or manmade 
factors affecting its continued existence. Listing actions may be 
warranted based on any of the above threat factors, singly or in

[[Page 61058]]

combination. Each of these factors is discussed below.
    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
to the eastern small-footed and northern long-eared bats. Effects to 
both the eastern small-footed bat and northern long-eared bat from 
these factors are discussed together where the species are affected 
similarly.
    There are several factors presented below that affect both the 
eastern small-footed and the northern long-eared bats to a greater or 
lesser degree; however, we have found that no other threat is as severe 
and immediate to the northern long-eared bat's persistence as the 
disease, white-nose syndrome (WNS), discussed below in Factor C. WNS is 
currently the predominant threat to the species, and if WNS had not 
emerged or was not affecting the northern long-eared bat populations to 
the level that it has, we presume the species' would not be 
experiencing the dramatic declines that it has since WNS emerged. 
Therefore, although we have included brief discussions of other factors 
affecting both species, the focus of the discussion below is on WNS.

Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range

Hibernation Habitat
    Modifications to bat hibernacula by erecting physical barriers 
(e.g., doors, gates) to control cave access and mining can affect the 
thermal regime of the habitat, and thus the ability of the cave or mine 
to support hibernating bats, including the northern long-eared and, in 
some cases, the eastern small-footed bat. For example, the Service's 
Indiana Bat Draft Recovery Plan (2007, pp. 71-74) presents a discussion 
of well-documented examples of these type of effectss to cave-
hibernating species that are also applicable to our discussion here. 
Modifications to cave and mine entrances, such as the addition of gates 
or other structures intended to exclude humans, not only restricts 
flight and movement (Hemberger 2011, unpublished data), but also 
changes airflow and alters internal microclimates of the caves and 
mines and eliminating their utility as hibernacula. For example, 
Richter et al. (1993, p. 409) attributed the decline in the number of 
Indiana bats at Wyandotte Cave, Indiana (which harbors one of the 
largest known population of hibernating Indiana bats), to an increase 
in the cave's temperature resulting from restricted airflow caused by a 
stone wall erected at the cave's entrance. After the wall was removed, 
the number of Indiana bats increased markedly over the next 14 years 
(Richter et al. 1993, p. 412; Brack et al. 2003, p. 67). In an eastern 
small-footed bat example, the construction associated with 
commercializing the Fourth Chute Cave in Ontario, Canada, eliminated 
the circulation of cold air in one of the unvisited passages where a 
relatively large number of eastern small-footed bats hibernated. These 
bats were completely displaced as a result of the warmer microclimate 
produced (Mohr 1972, p. 36). Correctly installed gates, however, at 
other locations (e.g., Aitkin Cave, Pennsylvania) have led to increases 
in eastern small-footed bat populations (Butchkoski 2012, pers. comm.). 
An example of northern long-eared bats likely being affected occurred 
when John Friend Cave in Maryland was filled with large rocks in 1981, 
which closed the only known entrance to the cave (Gates et al. 1984, p. 
166).
    In addition to the direct access modifications to caves discussed 
above, debris buildup at entrances or on cave gates can also 
significantly modify the cave or mine site characteristics through 
restricting airflow, altering the temperature of hibernacula, and 
restricting water flow. Water flow restriction could lead to flooding, 
thus drowning hibernating bats (Amelon and Burhans 2006, p. 72; 
Hemberger 2011, unpublished data). In Minnesota, 5 of 11 known northern 
long-eared bat hibernacula are known to flood, presenting a threat to 
hibernating bats (Nordquist 2012, pers. comm.). In Massachusetts, one 
of the known hibernacula for northern long-eared bats is a now unused 
aqueduct that on very rare occasions may fill up with water and make 
the hibernaculum unusable (French 2012, unpublished data). Flooding has 
been noted in hibernacula in other States within the range of the 
northern long-eared bat, but to a lesser degree. Although modifications 
to hibernacula can lead to mortality of both species, it has not had 
population-level effects.
    Mining operations, mine passage collapse (subsidence), and mine 
reclamation activities can also affect bats and their hibernacula. 
Internal and external collapse of abandoned coal mines was identified 
as one of the primary threats to eastern small-footed and northern 
long-eared bat hibernacula at sites located within the New River Gorge 
National River and Gauley River National Recreation Area in West 
Virginia (Graham 2011, unpublished data). Collapse of hibernacula 
entrances or areas within the hibernacula, as well as quarry and mining 
operations that may alter known hibernacula, are considered threats to 
northern long-eared bats within Kentucky (Hemberger 2011, unpublished 
data). In States surveyed for effects to northern long-eared bats by 
hibernacula collapse, responses varied, with the following number of 
hibernacula in each State reported as susceptible to collapse: 1 (of 7) 
in Maryland, 3 (of 11) in Minnesota, 1 (of 5) in New Hampshire, 4 (of 
15) in North Carolina, 1 (of 2) in South Carolina, and 1 (of 13) in 
Vermont (Service 2011, unpublished data).
    Before current cave protection laws, there were several reported 
instances where mines were closed while bats were hibernating and 
entombing entire colonies (Tuttle and Taylor 1998, p. 8). Several caves 
were historically sealed or mined in Maryland prior to cave protection 
laws, although bat populations were undocumented (Feller 2011, 
unpublished data). For both the eastern small-footed and northern long-
eared bats, loss of potential winter habitat through mine closures has 
been noted as a concern in Virginia, although visual inspections of 
openings are typically conducted to determine whether gating is 
warranted (Reynolds 2011, unpublished data). In Nebraska, closing 
quarries, and specifically sealing quarries in Cass and Sapry Counties, 
is considered a potential threat to northern long-eared bats (Geluso 
2011, unpublished data).
    In general, threats to the integrity of bat hibernacula have 
decreased since the Indiana bat was listed as endangered in 1967, and 
since the implementation of Federal and State cave protection laws. 
Increasing awareness about the importance of cave and mine 
microclimates to hibernating bats and regulation under the Act have 
helped to alleviate the destruction or modification of hibernation 
habitat, at least where the Indiana bat is present (Service 2007, p. 
74). The eastern small-footed bat and northern long-eared bat have 
likely benefitted from the protections given to the Indiana bat and its 
winter habitat, as both species' ranges overlap significantly with the 
Indiana bat's range.
Disturbance of Hibernating Bats
    Human disturbance of hibernating bats has long been considered a 
threat to cave-hibernating bat species like the eastern small-footed 
and northern long-eared bats, and is discussed in detail in the 
Service's Indiana Bat Draft Recovery Plan (2007, pp. 80-85). The 
primary forms of human disturbance to hibernating bats result from cave 
commercialization (cave tours and other commercial uses of caves), 
recreational

[[Page 61059]]

caving, vandalism, and research-related activities (Service 2007, p. 
80). Arousal during hibernation causes the greatest amount of energy 
depletion in hibernating bats (Thomas et al. 1990, p. 477). Human 
disturbance at hibernacula, specifically non-tactile disturbance such 
as changes in light and sound, can cause bats to arouse more 
frequently, causing premature energy store depletion and starvation, as 
well as increased tactile disturbance of bats to other individuals 
(Thomas et al. 1995, p. 944; Speakman et al. 1991, p. 1103), leading to 
marked reductions in bat populations (Tuttle 1979, p. 3). Prior to the 
outbreak of WNS, Amelon and Burhans (2006, p. 73) indicated that ``the 
widespread recreational use of caves and indirect or direct disturbance 
by humans during the hibernation period pose the greatest known threat 
to this species (northern long-eared bat).'' Olson et al. (2011, p. 
228), hypothesized that decreased visits by recreational users and 
researchers were related to an increase in the hibernating bat 
population (including northern long-eared bats) at Cadomin Cave in 
Alberta, Canada. Disturbance during hibernation could cause movements 
within or between caves (Beer 1955, p. 244).
    Human disturbance is a potential threat at approximately half of 
the known eastern small-footed bat hibernacula in the States of 
Kentucky, Maryland, North Carolina, Vermont, and West Virginia 
(Service, unpublished data). Of the States in the northern long-eared 
bat's range that assessed the possibility of human disturbance at bat 
hibernacula, 93 percent (13 of 14) identified potential effects from 
human disturbance for at least 1 of the known hibernacula for this 
species in their state (Service, unpublished data). Eight of these 14 
States (Arkansas, Kentucky, Maine, Minnesota, New Hampshire, North 
Carolina, South Carolina, and Vermont) indicated the potential for 
human disturbance at over 50 percent of the known hibernacula in that 
State. Nearly all States without WNS identified human disturbance as 
the primary threat to hibernating bats, and all others (including WNS-
positive States) noted human disturbance as a secondary threat (WNS was 
predominantly the primary threat in these States) or of significant 
concern (Service, unpublished data).
    The threat of commercial use of caves and mines during the 
hibernation period has decreased at many sites known to harbor Indiana 
bats, and we believe that this also applies to eastern small-footed and 
northern long-eared bats. However, effects from recreational caving are 
more difficult to assess. In addition to unintended effects of 
commercial and recreational caving, intentional killing of bats in 
caves by shooting, burning, and clubbing has been documented, although 
there are no data suggesting that eastern small-footed bats have been 
killed by these activities (Tuttle 1979, pp. 4, 8). Intentional killing 
of northern long-eared bats has been documented at a small percentage 
of hibernacula (e.g., several cases of vandalism at hibernacula in 
Kentucky, one case of shooting disturbance in Maryland, one case of bat 
torching in Massachusetts where approximately 100 bats (northern long-
eared bats and other species) were killed) (Service, unpublished data), 
but we do not have evidence that this is happening on a large enough 
scale to have population-level effects.
    In summary, while there are isolated incidents of previous 
disturbance to both bat species due to recreational use of caves in 
both species, we conclude that there is no evidence suggesting that 
this threat in itself has led to population declines in either species.
Summer Habitat
    Eastern small-footed bats roost in a variety of natural and manmade 
rock features, whereas northern long-eared bats roost predominantly in 
trees and to a lesser extent in manmade structures, as discussed in 
detail in the Species Information section above. We know of only one 
documented account where vandals were responsible for destroying a 
portion of an eastern small-footed bat roost located in Maryland 
(Feller 2011, unpublished data). More commonly, roost habitat for both 
the eastern small-footed bat and northern long-eared bat is at risk of 
modification or destruction. In Pennsylvania, for example, highway 
construction, commercial development, and several wind-energy projects 
may remove eastern small-footed bat roosting habitat (Librandi-Mumma 
2011, pers. comm.). Some of the highest rates of development in the 
conterminous United States are occurring within the range of eastern 
small-footed and northern long-eared bats (Brown et al. 2005, p. 1856) 
and contribute to loss of forest habitat.
    Wind-energy development is rapidly increasing throughout the 
eastern small-footed bat and northern long-eared bats' ranges, 
particularly in the States of New Hampshire, New York, Pennsylvania, 
and Massachusetts. As well, Iowa, Illinois, Minnesota, Oklahoma, and 
North Dakota are within the top 10 States for wind power capacity (in 
megawatts) (installed projects) in the United States (American Wind 
Energy Association 2012, p. 6). If projects are sited in forested 
habitats, effects from wind-energy development may include forest-
clearings associated with turbine placement, road construction, turbine 
lay-down areas, transmission lines, and substations. In Maryland, wind 
power development has been proposed in areas with documented eastern 
small-footed bat and northern long-eared bat summer habitat (Feller 
2011, unpublished data). In Pennsylvania, the majority of wind-energy 
projects are located in habitats characterized as mountain ridge-top, 
cliffs, steep slopes, or isolated hills with steep, often vertical 
sides (Mumma and Capouillez 2011, pp. 11-12). Eastern small-footed bats 
were confirmed through bat mist-net surveys at 7 of 34 proposed wind-
energy project sites in Pennsylvania, and northern long-eared bats were 
confirmed at all 34 proposed wind project sites (Mumma and Capouillez 
2011, pp. 62-63). See Factor E. Other Natural or Manmade Factors 
Affecting Its Continued Existence for a discussion on effects to bats 
from the operation of wind turbines.
    Another activity that may modify or destroy eastern small-footed 
bat roosting habitat is mined-land reclamation, whereby rock habitats 
(e.g., rock piles, cliffs, spoil piles) are removed from previously 
mined lands. The Office of Surface Mining Reclamation and Enforcement 
and its partners are responsible for reclaiming and restoring lands 
degraded by mining operations. Mining sites eligible for restoration 
are numerous in the States of Pennsylvania, Ohio, West Virginia, and 
Kentucky. Reclaiming these sites often involves the removal of exposed 
rock habitats that may be used as eastern small-footed bat roost 
habitat (Sanders 2011, pers. comm.). The number of potential roost 
sites that have been destroyed or that may be destroyed in the future 
and the potential effect of this destruction on eastern small-footed 
bat populations are largely unknown. Despite the potential negative 
effects of this activity, there are no data available suggesting a 
decrease in the number of eastern small-footed bats from mined-land 
reclamation activities. Since northern long-eared bats are not known to 
use exposed rock habitat for roost sites, mined-land reclamation does 
not affect this species.
    Surface coal mining is also common in the central Appalachian 
region, which includes portions of Pennsylvania, West Virginia, 
Virginia, Kentucky, and Tennessee, and is one of the major drivers of 
land cover change in the region (Sayler 2008, unpaginated). Surface 
coal mining also may destroy forest habitat in parts of the Illinois 
Basin in southwest Indiana, western Kentucky, and Illinois (King

[[Page 61060]]

2013, pers. comm.). One major form of surface mining is mountaintop 
mining, which is widespread throughout eastern Kentucky, West Virginia, 
and southwestern Virginia (Palmer et al. 2010, p. 148). Mountaintop 
mining involves the clearing of upper elevation forests, stripping of 
topsoil, and use of explosives to break up rocks to access buried coal. 
The excess rock is sometimes pushed into adjacent valleys, where it 
buries existing streams (Palmer et al. 2010, p. 148). Hartman et al. 
(2005, p. 96) reported significant reductions in insect densities in 
streams affected with fill material, including lower densities of 
coleopterans, a primary food source of eastern small-footed and 
northern long-eared bats (Griffith and Gates 1985, p. 452; Johnson and 
Gates 2007, p. 319; Moosman et al. 2007, p. 355; Feldhamer et al. 2009, 
p. 45). The effect of mountaintop mining on eastern small-footed bat 
and northern long-eared bat populations is largely unknown.
    The effect of forest removal related to the eastern small-footed 
bat is poorly understood. Forest management can influence the 
availability and characteristics of non-tree roost sites, such as those 
used by eastern small-footed bats, although the resulting effects on 
bats and bat populations are poorly known (Hayes and Loeb 2007, p. 
215). Since eastern small-footed bats often forage in forests 
immediately surrounding roost sites, forest management may affect the 
quality of foraging habitat (Johnson et al. 2009, p. 5). Scientific 
evidence and anecdotal observations support the hypotheses that bats 
respond to prey availability, that prey availability is influenced by 
forest management, and that influences of forest management on prey 
populations affect bat populations (Hayes and Loeb 2007, p. 219). In 
addition, forest management activities that influence tree density 
directly alter the amount of vegetative clutter (e.g., tree density) in 
an area. As a result, forest management can directly influence habitat 
suitability for bats through changes in the amount of vegetative 
clutter (Hayes and Loeb 2007, p. 217). Eastern small-footed bats are 
capable of foraging in cluttered forest interiors, but as discussed in 
the Species Information section above, they have also been found 
foraging in clearings, in strip mine areas, and over water. Johnson and 
Gates (2008, p. 459) suggest that a better understanding of the 
required spatial extent and structure of forest cover along ridgelines 
and rock outcrops, as well as additional foraging activity 
requirements, is needed to aid conservation efforts for the eastern 
small-footed bat.
    Although there is still much to learn about the effects of forest 
removal on northern long-eared bats and their associated summer 
habitat, studies to date have found that the northern long-eared bat 
shows a varied degree of sensitivity to timber harvesting practices. 
Several studies (as discussed in the Species Information section above) 
have found that the species uses a wide range of tree species for 
roosting, suggesting that forest succession may play a larger role in 
roost selection (than tree species) (Silvis et al. 2012, p. 6). Studies 
have found that female bat roosts are more often (i.e., greater than 
what would be expected from random chance) located in areas with 
partial harvesting than in random sites, which may be due to trees 
located in more open habitat receiving greater solar radiation and 
therefore speeding development of young (Menzel et al. 2002, p. 112; 
Perry and Thill 2007, pp. 224-225). In the Appalachians of West 
Virginia, diameter-limit harvests (70-90 year-old stands, with 30-40 
percent of the basal area removed in the past 10 years) rather than 
intact forest was the habitat type most selected by northern long-eared 
bats (Owen et al. 2003, p. 356). Cryan et al. (2001, p. 49) found 
several northern long-eared bat roost areas in recently harvested (less 
than 5 years) stands in the Black Hills of South Dakota, although the 
largest colony (n=41) was found in a mature forest stand that had not 
been harvested in over 50 years. In intensively managed forests in the 
central Appalachians, Owen et al. (2002, p. 4) found roost availability 
was not a limiting factor for the northern long-eared bat, since bats 
often chose black locust and black cherry as roost trees, which were 
quite abundant since these trees often regenerate quickly after 
disturbance (e.g., timber harvest).
    It is possible that this flexibility in roosting habits allows 
northern long-eared bats to be adaptable in managed forests, which 
allows them to avoid competition for roosting habitat with more 
specialized species, such as the Indiana bat (Timpone et al. 2010, p. 
121). However, the northern long-eared bat has shown a preference for 
contiguous tracts of forest cover for foraging (Owen et al. 2003, p. 
356; Yates and Muzika 2006, p. 1245). Jung et al. (2004, p. 333) found 
that it is important to retain snags and provide for recruitment of 
roost trees during selective harvesting in forest stands that harbor 
bats. If roost networks are disturbed through timber harvesting, there 
may be more dispersal and fewer shared roost trees, which may lead to 
less communication between bats in addition to less disease 
transmission (Johnson et al. 2012, p. 230). In the Appalachians, Ford 
et al. (2006, p. 20) assessed that northern long-eared bats may be a 
suitable management indicator species for assessing mature forest 
ecosystem integrity, since they found male bats using roosts in mature 
forest stands of mostly second growth or regenerated forests.
    There is conflicting information on sensitivities of male versus 
female northern long-eared bats to forestry practices and resulting 
fragmentation. In Arkansas, Perry and Thill (2007, p. 225) found that 
male northern long-eared bats seem to prefer more dense stands for 
summer roosting, with 67 percent of male roosts occurring in 
unharvested sites versus 45 percent of female roosts. The greater 
tendency of females to roost in more open forested areas than males may 
be due to greater solar radiation experienced in these openings, which 
could speed growth of young in maternity colonies (Perry and Thill 
2007, p. 224). Lacki and Schwierjohann (2001, p. 487) stated that 
silvicultural practices could meet both male and female roosting 
requirements by maintaining large-diameter snags, while allowing for 
regeneration of forests. However, Broders and Forbes (2004, p. 608) 
found that timber harvest may have negative effects on female bats 
since they use forest interiors at small scales (less than 2 km (1.2 
mi) from roost sites). They also found that males are not as limited in 
roost selection and they do not have the energetic cost of raising 
young; therefore males may be less affected than females (Broders and 
Forbes 2004, p. 608). Henderson et al. (2008, p. 1825) also found that 
forest fragmentation effects northern long-eared bats at different 
scales based on sex; females require a larger unfragmented area with a 
large number of suitable roost trees to support a colony, whereas males 
are able to use smaller areas (more fragmented). Henderson and Broders 
(2008, pp. 959-960) examined how female northern long-eared bats use 
the forest-agricultural landscape on Prince Edward Island, Canada, and 
found that bats were limited in their mobility and activities are 
constrained where suitable forest is limited. However, they also found 
that bats in relatively fragmented areas used a building for colony 
roosting, which suggests an alternative for a colony to persist in an 
area with fewer available roost trees. Although we are still learning 
about the effect of forest removal on northern long-eared

[[Page 61061]]

bats and their associated summer habitat, studies to date have found 
that the northern long-eared bat shows a varied degree of sensitivity 
to timber harvesting practices and the amount of forest removal 
occurring varies by State.
    Natural gas development from shale is expanding across the United 
States, particularly throughout the range of the northern long-eared 
and eastern small-footed bat. Natural gas extraction involves 
fracturing rock formations and uses highly pressurized fluids 
consisting of water and various chemicals to do so (Hein 2012, p. 1). 
Natural gas extraction, particularly across the Marcellus Shale region, 
which includes large portions of New York, Pennsylvania, Ohio, and West 
Virginia, is expected to expand over the coming years. In Pennsylvania, 
for example, nearly 2,000 Marcellus natural gas wells have already been 
drilled or permitted, and as many as 60,000 more could be built by 
2030, if development trends continue (Johnson 2010, pp. 8, 13). Habitat 
loss and degradation due to this practice could occur in the form of 
forest clearing for well pads and associated infrastructure (e.g., 
roads, pipelines, and water impoundments), which would decrease the 
amount of suitable interior forest habitat available to northern long-
eared and eastern small-footed bats for establishing maternity colonies 
and for foraging, in addition to further isolating populations and, 
therefore, potentially decreasing genetic diversity (Johnson 2010, p. 
10; Hein 2012, p. 6). Since northern long-eared bats and eastern small-
footed bats have philopatric tendencies, loss or alteration of forest 
habitat for natural gas development may also put additional stress on 
females when returning to summer roost or foraging areas after 
hibernation if females were forced to find new roosting or foraging 
areas (expend additional energy) (Hein 2012, pp. 11-12).
Conservation Efforts To Reduce Habitat Destruction, Modification, or 
Curtailment of Its Range
    Although there are various forms of habitat destruction and 
disturbance that present potential adverse effects to the northern 
long-eared bat, this is not considered the predominant threat to the 
species. Even if all habitat-related stressors were eliminated or 
minimized, the significant effects of WNS on the northern long-eared 
bat would still be present. Therefore, below we present a few examples, 
but not a comprehensive list, of conservation efforts that have been 
undertaken to lessen effects from habitat destruction or disturbance to 
northern long-eared and eastern small-footed bats. One of the threats 
to bats in Michigan is the closure of unsafe mines in such a way that 
bats are trapped within or excluded; however, there have been efforts 
by the Michigan Department of Natural Resources and others to work with 
landowners who have open mines to encourage them to install bat-
friendly gates to close mines to humans, but allow access to bats 
(Hoving 2011, unpublished data). The NPS has proactively taken efforts 
to minimize effects to bat habitat resulting from vandalism, 
recreational activities, and abandoned mine closures (Plumb and Budde 
2011, unpublished data). In addition, the NPS is properly gating, using 
a ``bat-friendly design, abandoned coal mine entrances as funding 
permits (Graham 2011, unpublished data). All known hibernacula within 
national grasslands and forestlands of the Rocky Mountain Region of the 
U.S. Forest Service are closed during the winter hibernation period, 
primarily due to the threat of white-nose syndrome, although this will 
reduce disturbance to bats in general inhabiting these hibernacula 
(U.S. Forest Service 2013, unpaginated). Concern over the importance of 
bat roosts, including hibernacula, fueled efforts by the American 
Society of Mammalogists to develop guidelines for protection of roosts, 
many of which have been adopted by government agencies and special 
interest groups (Sheffield et al. 1992, p. 707).
Summary of the Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range
    We have identified several activities, such as constructing 
physical barriers at cave accesses, mining, flooding, vandalism, 
development, and timber harvest, that may modify or destroy habitat for 
the eastern small-footed bat and northern long-eared bat. Although such 
activities occur, these activities alone do not have significant, 
population-level effects on either species.

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    There are very few records of either species being collected 
specifically for commercial, recreational, scientific, or educational 
purposes, and thus we do not consider such collection activities to 
pose a threat to either species. Disturbance of hibernating bats as a 
result of recreational use and scientific research activities in 
hibernacula is discussed under Factor A.

Factor C. Disease or Predation

Disease
White-Nose Syndrome
    White-nose syndrome is an emerging infectious disease responsible 
for unprecedented mortality in some hibernating insectivorous bats of 
the northeastern United States (Blehert et al. 2009, p. 227), and poses 
a considerable threat to several hibernating bat species throughout 
North America (Service 2010, p. 1). Since its first documented 
appearance in New York in 2006, WNS has spread rapidly throughout the 
Northeast and is expanding through the Midwest. As of August 2013, WNS 
has been confirmed in 22 States (Alabama, Connecticut, Delaware, 
Georgia, Illinois, Indiana, Kentucky, Maine, Maryland, Massachusetts, 
Missouri, New Hampshire, New Jersey, New York, North Carolina, Ohio, 
Pennsylvania, South Carolina, Tennessee, Vermont, Virginia, and West 
Virginia) and 5 Canadian provinces (New Brunswick, Nova Scotia, 
Ontario, Prince Edward Island, and Quebec). Four additional States 
(Arkansas, Iowa, Minnesota, and Oklahoma) are considered suspect for 
WNS based on the detection of the causative fungus on bats within those 
States, but with no associated disease to date. Service biologists and 
partners estimate that at least 5.7 million to 6.7 million bats of 
several species have now died from WNS (Service 2012, p. 1). Dzal et 
al. (2011, p. 393) documented a 78-percent decline in the summer 
activity of little brown bats in New York State, coinciding with the 
arrival and spread of WNS, suggesting large-scale population effects. 
Turner et al. (2011, p. 22) reported an 88-percent decline in the 
number of hibernating bats at 42 sites from the States of New York, 
Pennsylvania, Vermont, Virginia, and West Virginia. Furthermore, Frick 
et al. (2010, p. 681) predicted that the little brown bat, formerly the 
most common bat in the northeastern United States, will likely become 
extinct in the region by 2026 (potential loss of some 6.5 million bats) 
if current trends continue. Similarly, Thogmartin et al. (2013, p. 171) 
predicted that WNS is likely to extirpate the federally endangered 
Indiana bat over large parts of its range. These predicted trends in 
little brown bats and Indiana bats may or may not also be indicative of 
population trends in other bat species like the eastern small-footed 
and northern long-eared bats.
    The first evidence of WNS was documented in a photograph taken from 
Howes Cavern, 52 km (32 mi) west of

[[Page 61062]]

Albany, New York, on February16, 2006 (Blehert et al. 2009, p. 227). 
Prior to the arrival of WNS, surveys of six species of hibernating bats 
in New York State revealed that populations had been stable or 
increasing in recent decades (Service 2010, p. 1). Decreases in some 
species of bats at WNS-infected hibernacula have ranged from 30 to 99 
percent (Frick et al. 2010, p. 680).
    The pattern of spread has generally followed predictable 
trajectories along recognized migratory pathways and overlapping summer 
ranges of hibernating bat species. Therefore, Kunz and Reichard (2010, 
p. 12) assert that WNS is spread mainly through bat-to-bat contact; 
however, evidence suggests that fungal spores can be transmitted by 
humans (United States Geologic Survey (USGS) National Wildlife Health 
Center, Wildlife Health Bulletin 2011-05), and bats can also become 
infected by coming into contact with contaminated cave substrate 
(Darling 2012, pers. comm.). Six North American hibernating bat species 
(little brown bat, Indiana bat, northern long-eared bat, eastern small-
footed bat, big brown bat, and tri-colored bat), are known to be 
affected by WNS; however, the effect of WNS varies by species. The 
fungus that causes WNS has been detected on three additional species; 
the southeastern bat (Myotis austroriparius), and gray bat (Myotis 
grisescens), and cave bat (Myotis velifer). White-nose syndrome is 
caused by the recently described psychrophilic (cold-loving) fungus, 
currently known as Geomyces destructans. Geomyces destructans may be 
nonnative to North America, and only recently arrived on the continent 
(Puechmaille et al. 2011, p. 8). The fungus grows on and within exposed 
tissues of hibernating bats (Lorch et al. 2011, p. 376; Gargas et al. 
2009, pp. 147-154)), and the diagnostic feature is the white fungal 
growth on muzzles, ears, or wing membranes of affected bats, along with 
epidermal (skin) erosions that are filled with fungal hyphae 
(branching, filamentous structures of fungi) (Blehert et al. 2009, p. 
227; Meteyer 2009, p. 412). Geomyces destructans grows optimally at 
temperatures from 5 to 10 [deg]C (41 to 50 [deg]F), the same 
temperatures at which bats typically hibernate (Blehert et al. 2009, p. 
227). Temperatures in WNS-affected hibernacula seasonally range from 2 
to 14 [deg]C (36 to 57 [deg]F), permitting year-round growth, and may 
act as a reservoir maintaining the fungus (Blehert et al. 2009, p. 
227). Growth is slow, and no growth occurs at temperatures above 24 
[deg]C (75 [deg]F) (Gargas et al. 2009, p. 152). Bats that are found in 
more humid regions of hibernacula may be more susceptible to WNS, but 
further research is needed to confirm this hypothesis. Declines in 
Indiana bats have been greater under more humid conditions, suggesting 
that growth of the fungus and either intensity or prevalence of 
infections are higher in more humid conditions (Langwig et al. 2012a, 
p. 1055). Although G. destructans has been isolated from five bat 
species from Europe, research suggests that bat species in Europe may 
be immunologically or behaviorally resistant, having coevolved with the 
fungus (Wibbelt et al. 2010, p. 1241). Pikula et al. (2012, p. 210), 
however, confirmed that bats found dead in the Czech Republic exhibited 
lesions consistent with WNS infection.
    In addition to the presence of the white fungus, initial 
observations showed that bats affected by WNS were characterized by 
some or all of the following: (1) Depleted fat reserves by mid-winter; 
(2) a general unresponsiveness to human disturbance; (3) an apparent 
lack of immune response during hibernation; (4) ulcerated, necrotic, 
and scarred wing membranes; and (5) aberrant behaviors, including 
shifts of large numbers of bats in hibernacula to roosts near the 
entrances or unusually cold areas, large numbers of bats dispersing 
during the day from hibernacula during mid-winter, and large numbers of 
fatalities, either inside the hibernacula, near the entrance, or in the 
immediate vicinity of the entrance (WNS Science Strategy Report 2008, 
p. 2; Service 2010, p. 2). Although the exact process by which WNS 
leads to death remains undetermined, it is likely that the immune 
function during torpor compromises the ability of hibernating bats to 
combat the infection (Bouma et al. 2010, p. 623; Moore et al. 2011, p. 
10).
    Early hypotheses suggested that WNS may affect bats before the 
hibernation season begins, causing bats to arrive at hibernacula with 
insufficient fat to survive the winter. Alternatively, a second 
hypothesis suggests that bats arrive at hibernacula unaffected and 
enter hibernation with sufficient fat stores, but then become affected 
and use fat stores too quickly as a result of disruption to hibernation 
physiology (WNS Science Strategy Group 2008, p. 7). More recent 
observations, however, suggest that bats are arriving to hibernacula 
with sufficient or only slightly lower fat stores (Turner 2011, pers. 
comm.), and that although body weights of WNS-infected bats were 
consistently at the lower end of the normal range, in one study 12 of 
14 bats (10 little brown bats, 1 big-brown bat, and 1 tri-colored bat) 
had an appreciable degree of fat stores (Courtin et al. 2010, p. 4).
    Boyles and Willis (2010, pp. 92-98) hypothesized that infection by 
Geomyces destructans alters the normal arousal cycles of hibernating 
bats, particularly by increasing arousal frequency, duration, or both. 
In fact, Reeder et al. (2012, p. 5) and Warnecke et al. (2012, p. 2) 
did observe an increase in arousal frequency in laboratory studies of 
hibernating bats infected with G. destructans. A disruption of this 
torpor-arousal cycle could easily cause bats to metabolize fat reserves 
too quickly, thereby leading to starvation. For example, skin 
irritation from the fungus might cause bats to remain out of torpor for 
longer than normal to groom, thereby exhausting their fat reserves 
prematurely (Boyles and Willis 2010, p. 93).
    Due to the unique physiological importance of wings to hibernating 
bats in relation to the damage caused by Geomyces destructans, Cryan et 
al. (2010, pp. 1-8) suggests that mortality may be caused by 
catastrophic disruption of wing-dependent physiological functions. The 
authors hypothesize that G. destructans may cause unsustainable 
dehydration in water-dependent bats, trigger thirst-associated 
arousals, cause significant circulatory and thermoregulatory 
disturbance, disrupt respiratory gas exchange, and destroy wing 
structures necessary for flight control (Cryan et al. 2010, p. 7). The 
wings of winter-collected WNS-affected bats often reveal signs of 
infection, whereby the degree of damage observed suggests functional 
impairment. Emaciation is a common finding in bats that have died from 
WNS (Cryan et al. 2010, p. 3). Cryan et al. (2010, p. 3) hypothesized 
that disruption of physiological homeostasis, potentially caused by G. 
destructans infection, may be sufficient to result in emaciation and 
mortality. The authors hypothesized that wing damage caused by G. 
destructans infections could sufficiently disrupt water balance to 
trigger frequent thirst-associated arousals with excessive winter 
flight, and subsequent premature depletion of fat stores. In related 
research, Cryan et al. (2013, p. 398) found, after analyzing blood from 
hibernating bats infected with WNS, that electrolytes, sodium and 
chloride, tended to decrease as wing damage increased in severity. 
Proper concentrations of electrolytes are necessary for maintaining 
physiologic homeostasis, and any imbalance could be life-threatening 
(Cryan et al. 2013, p. 398). Although the exact mechanism by which WNS 
affects bats is still in

[[Page 61063]]

question, the effect it has on many hibernating bat species is well 
documented as well as the high levels of mortality it causes in some 
susceptible bat species.
Effects of White-Nose Syndrome on the Eastern Small-Footed Bat
    Eastern small-footed bats are known to be susceptible to WNS. As of 
2011, of the 283 documented eastern small-footed bat hibernacula, 86 
(31 percent) were WNS-positive (Service 2011, unpublished data). Only 
three eastern small-footed bats have been collected, tested, and 
confirmed positive for WNS by histology: One bat collected and 
euthanized from New York in 2009, one bat found dead in Pennsylvania in 
2011, and one bat found dead from South Carolina in 2013 (Ballmann 
2011, pers. comm.; Last 2013a, pers. comm.). An additional eastern 
small-footed bat collected in winter 2011-2012 from the Mammoth Cave 
Visitor Center in Kentucky, was submitted to the Southeastern 
Cooperative Wildlife Disease Study; however, this bat tested negative 
for WNS. Biologists also observed approximately five dead eastern 
small-footed bats with obvious signs of fungal infection in Virginia 
(Reynolds 2011, pers. comm.).
    To determine whether WNS is causing a population-level effect to 
eastern small-footed bats, the Service began by reviewing winter 
hibernacula survey data. By comparing the most recent pre-WNS count to 
the most recent post-WNS count, Turner et al. (2011, p. 22) reported a 
12-percent decline in the number of hibernating eastern small-footed 
bats at 25 hibernacula in New York, Pennsylvania, Vermont, Virginia, 
and West Virginia. Data analyzed in this study were limited to sites 
with confirmed WNS mortality for at least 2 years and sites with 
comparable survey effort across pre- and post-WNS years. Based on a 
review of pre-WNS hibernacula count data over multiple years at 12 of 
these sites, the number of eastern small-footed bats fluctuated between 
years.
    When we compared the most recent post-WNS eastern small-footed bat 
count to pre-WNS observations, we found that post-WNS counts were 
within the normal observed range at nine sites (75 percent), higher at 
two sites (17 percent), and lower at only one site (8 percent). In 
addition, although Langwig et al. (2012a, p. 1052) reported a 
significantly lower population growth rate compared to pre-WNS 
population growth rates for eastern small-footed bat, they found that 
the species was not declining significantly at hibernacula in New York, 
Vermont, Connecticut, and Massachusetts. Langwig et al. (2012b, p. 15) 
also observed lower prevalence of Geomyces destructans on eastern 
small-footed bat wing and muzzle tissue during late hibernation, 
compared to other bat species (e.g., little brown bats). Lastly, 
biologists did not observe fungal growth (although the fungus may not 
be visible after the first couple of years) on eastern small-footed 
bats during 2013 hibernacula surveys in New York, Pennsylvania, and 
North Carolina, even though it was observed on other bat species (e.g., 
little brown bats) within the same sites (although a few, not all, 
eastern small-footed bats viewed under ultraviolet light did show signs 
of mild infections), nor did they observe reduced numbers of eastern 
small-footed bats compared to pre-WNS years (Graeter 2013, pers. comm.; 
Herzog 2013, pers. comm.; Turner 2013, unpublished data). In fact, 
biologists in New York observed the largest number of hibernating 
eastern small-footed bats ever reported (2,383) during surveys 
conducted in 2013, up from 1,727 reported in 1993 using roughly 
comparable survey effort (Herzog 2013, pers. comm.). In summary, WNS 
does not appear to have caused a significant population decline in 
hibernating eastern small-footed bats.
    Summer survey data are limited for the eastern small-footed bat. We 
know of only three studies that have attempted to quantify changes in 
the number of non-hibernating eastern small-footed bats since the 
spread of WNS (Francl et al. 2012; Nagel and Gates 2012; Moosman et al. 
in press). At one study location, Surry Mountain Reservoir, New 
Hampshire, bats were mist-netted over multiple years before and after 
the emergence of WNS (Moosman et al. in press). Researchers observed a 
significant decline in the relative abundance of eastern small-footed 
bats between 2005 and 2011, based on reductions in capture rates. 
However, they found that the probability of capturing greater than or 
equal to one eastern small-footed bat on any given visit during the 7 
years of study was similar across years, although the probability of 
capturing other species (e.g., northern long-eared and little brown 
bats) declined over time. Moosman et al. (unpublished data) also noted 
that the observed decline in relative abundance of eastern small-footed 
bats at their site should not be solely attributed to WNS because of 
the potential for bats to become trap-shy due to repeated sampling 
efforts.
    Eastern small-footed bats are noted for their ability to detect and 
avoid mist-nets, perhaps more so than other bat species within their 
range (Tyburec 2012, unpaginated). In addition, Francl et al. (2012, p. 
34) compared bat mist-net data collected from 31 counties in West 
Virginia prior to the detection of WNS (1997 to 2008) to 8 West 
Virginia and 1 extreme southwestern Pennsylvania counties surveyed in 
2010. Researchers reported a 16-percent decline in the post-WNS capture 
rate for eastern small-footed bats, although they acknowledge the small 
sample size may have inherently higher variation and bias compared to 
more common species that showed consistently negative trends (e.g., 
northern long-eared, little brown, and tri-colored bats) (Francl et al. 
2012, p. 40). Lastly, during acoustic surveys for bats, Nagel and Gates 
(2012, p. 5) reported a 63-percent increase in the number of eastern 
small-footed bat passes during acoustic surveys from 2010 to 2012 in 
western Maryland, although large declines in bat passes were observed 
for other species (e.g., northern long-eared, little brown/Indiana, and 
tri-colored bats).
    Several factors may influence why eastern small-footed bats are 
potentially less susceptible to WNS than other Myotis bats. First, 
during mild winters, eastern small-footed bats may not enter caves and 
mines or, if they do, may leave during mild periods. Although there are 
few winter observations of this species outside of cave and mine 
habitat, it was first speculated in 1945 as a possibility. In trying to 
explain why so many bats banded in the summer were unaccounted for 
during winter hibernacula surveys, Griffin (1945, p. 22) suggested that 
bats may be using alternate hibernacula such as small, deep crevices in 
rocks, which he suggested would provide a bat with adequate protection 
from freezing. Neubaum et al. (2006, p. 476) observed many big brown 
bats choosing hibernation sites in rock crevices and speculated that 
this pattern of roost selection could be common for other species. Time 
spent outside of cave and mine habitat by eastern small-footed bats 
means less time for the fungus to grow because environmental conditions 
(e.g., temperature and humidity) are suboptimal for fungus growth.
    A second factor that may influence lower susceptibility of eastern 
small-footed bats to WNS is that this bat species tends to enter cave 
or mine habitat later (mid-November) and leave earlier (mid-March) 
compared to other Myotis bats, again providing less time for the fungus 
to grow, and less energy expenditure than other species that hibernate 
longer. Third, when eastern small-footed bats are present at caves and 
mines, they are most frequently observed at the entrances, where

[[Page 61064]]

humidity is low and temperature fluctuations are high, which 
consequently does not provide ideal environmental conditions for fungal 
growth. Cryan et al. (2010, p. 4) suggest that eastern small-footed 
bats may be less susceptible to evaporative water loss, since they 
often select drier areas of hibernacula, and therefore may be less 
susceptible to succumbing to WNS. Big brown bats also tend to select 
drier, more ventilated areas for hibernation, and consequently, Blehert 
et al. (2009, p. 227) and Courtin et al. (2010, p. 4) did not observe 
the fungus in big brown bat specimens. Lastly, unlike some other 
gregarious bats (e.g., little brown bats), eastern small-footed bats 
frequently roost solitarily or deep within cracks, possibly further 
reducing their exposure to the fungus.
    Fenton (1972, p. 5) never observed eastern small-footed bats close 
to or in contact with little brown or Indiana bats, both highly 
gregarious species experiencing severe population declines. Solitary 
hibernating habits have also been suggested as one of the reasons why 
big brown bats appear to have been only moderately affected by WNS 
(Ford et al. 2011, p. 130). Laboratory studies conducted by Blehert et 
al. (2011) further support this hypothesis. In their study, only 
healthy bats that came into direct contact with infected bats or were 
inoculated with pure cultures of Geomyces destructans developed lesions 
consistent with WNS. Healthy bats housed with infected bats in such a 
way as to prohibit animal-to-animal contact but still allow for 
potential aerosols to be transmitted from sick bats did not develop any 
detectable signs of WNS.
    In conclusion, there are several factors that may explain why 
eastern small-footed bats appear to be less susceptible to WNS than 
other cave bat species. These factors include hibernacula selection 
(cave versus non-cave), total time spent hibernating in hibernacula, 
location within the hibernacula (areas with lower humidity and higher 
temperature fluctuation), and solitary roosting behavior.
Effects of White-Nose Syndrome on the Northern Long-Eared Bat
    The northern long-eared bat is known to be susceptible to WNS, and 
mortalities due to the disease have been confirmed. The USGS National 
Wildlife Health Center in Madison, Wisconsin, received 79 northern 
long-eared bat submissions since 2007, of which 65 were tested for WNS. 
Twenty-eight of the 65 northern long-eared bats tested were confirmed 
as positive for WNS by histopathology and another 10 were suspect 
(Ballmann 2013, pers. comm.). In addition, 9 of 14 northern long-eared 
bats in 2012-2013 were positive, and 1 was suspect (Last 2013b, pers. 
comm.); all the WNS-positive submissions were from Tennessee, Kentucky, 
and Ohio. The New York Department of Environmental Conservation has 
confirmed 29 northern long-eared bats submitted with signs of WNS, at 
minimum (there are still bat carcasses that have not been analyzed 
yet), since 2007 in New York (Okonieski 2012, pers. comm.).
    Due to WNS, the northern long-eared bat has experienced a sharp 
decline in the northeastern part of its range, as evidenced in 
hibernacula surveys. The northeastern United States is very close to 
saturation (WNS found in majority of hibernacula) for the disease, with 
the northern long-eared bat being one of the species most severely 
affected by the disease (Herzog and Reynolds 2012, p. 10). Turner et 
al. (2011, p. 22) compared the most recent pre-WNS count to the most 
recent post-WNS count for 6 cave bat species; they reported a 98-
percent decline between pre- and post-WNS in the number of hibernating 
northern long-eared bats at 30 hibernacula in New York, Pennsylvania, 
Vermont, Virginia, and West Virginia. Data analyzed in this study were 
limited to sites with confirmed WNS mortality for at least 2 years and 
sites with comparable survey effort across pre and post-WNS years. In 
addition to the Turner et al. (2011) data, the Service conducted an 
additional analysis that included data from Connecticut (n=3), 
Massachusetts (n=4), and New Hampshire (n=4), and added one additional 
site to the previous Vermont data. We used a similar protocol for 
analyses as used in Turner et al. (2011); our analysis was limited to 
sites where WNS has been present for at least 2 years. The combined 
overall rate of decline seen in hibernacula count data for the 8 States 
is approximately 99 percent.
    In hibernacula surveys in New York, Vermont, Connecticut, and 
Massachusetts, hibernacula with larger populations of northern long-
eared bats experienced greater declines, suggesting a density-dependent 
decline due to WNS (Langwig et al. 2012a, p. 1053). Also, although some 
species' populations (e.g., tri-colored bat, Indiana bat) stabilized at 
drastically reduced levels compared to pre-WNS, each of the 14 
populations of northern long-eared bats became locally extinct within 2 
years due to disease, and no population was remaining 5 years post-WNS 
(Langwig et al. 2012, p. 1054). During 2013 hibernacula surveys at 34 
sites where northern long-eared bats were also observed prior to WNS in 
Pennsylvania, researchers found a 99-percent decline (from 637 to 5 
bats) (Turner 2013, unpublished data).
    Due to favoring small cracks or crevices in cave ceilings, making 
them more challenging to locate during hibernacula surveys, data in 
some States (particularly those with a greater number of caves with 
more cracks or crevices) may not give an entirely clear picture of the 
level of decline the species is experiencing (Turner et al. 2011, p. 
21). When dramatic declines due to WNS occur, the overall rate of 
decline appears to vary by site; some sites experience the progression 
from the detection of a few bats with visible fungus to widespread 
mortality after a few weeks, while at other sites this may take a year 
or more (Turner et al. 2011, pp. 20-21). For example, in Massachusetts, 
WNS was first confirmed in February of 2008, and by 2009, ``the 
population (northern long-eared bat) was knocked down, and the second 
year the population was finished'' (French 2012, pers. comm.). Further, 
in Virginia, Reynolds (2012, pers. comm.) reported that ``not all sites 
are on the same `WNS time frame,' but it appears the effects will be 
similar, suggesting that all hibernacula in the mountains of Virginia 
will succumb to WNS at one time or another.'' We have not yet seen the 
same level of decline in the Midwestern and southern parts of the 
species' range, although we expect similar rates of decline once the 
disease arrives or becomes more established.
    Although the disease has not yet spread throughout the species' 
entire range (WNS is currently found in 22 of 39 States where the 
northern long-eared bat occurs), it continues to spread, and we have no 
reason not to expect that where it spreads, it will have the same 
impact to the affected species (Coleman 2013, pers. comm.). The current 
rate of spread has been rapid, spreading from the first documented 
occurrence in New York in February 2006, to 22 states and 5 Canadian 
provinces by July 2013. There is some uncertainty as to the timeframe 
when the disease will spread throughout the species' range and when 
resulting mortalities as witnessed in the currently affected area will 
occur in the rest of the range. Researchers have suggested that there 
may be a `slow down' in the spread of the disease in the Great Plains 
(Frick and Kilpatrick 2013, pers. comm.); however, this is on the 
western edge of the northern long-eared bat's range where the species 
is naturally less common and, therefore, offers little respite to the 
species. A few models have attempted to project the

[[Page 61065]]

spread of Geomyces destructans and WNS, and although they have differed 
in the timing of the disease spreading throughout the continental 
United States, all were in agreement that WNS will indeed spread 
throughout the United States (Hallam et al. 2011, p. 8; Maher et al. 
2012, pp. 4-5). One of these models suggests that there may be a 
temperature-dependent boundary in southern latitudes that may offer 
refuge to WNS-susceptible bats. However, this would likely provide 
little relief to the northern long-eared bat, since the species' range 
only slightly enters these southern states (Hallam et al. 2011, pp. 9-
11). In addition, human transmission could introduce the spread of the 
fungus to new locations that are far removed from the current known 
locations (e.g., spread the fungus farther than an infected bat could 
transmit it within their natural movement patterns) (Coleman 2013, 
pers. comm.).
    Long-term (including pre- and post-WNS) summer data for the 
northern long-eared bat are somewhat limited; however, the available 
data parallel the population decline exhibited in hibernacula surveys. 
Summer data can corroborate and confirm the decline to the species seen 
in hibernacula data. Summer surveys from 2005-2011 near Surry Mountain 
Lake in New Hampshire showed a 99-percent decline in capture success of 
northern long-eared bats post-WNS, which is similar to the hibernacula 
data for the State (a 95-percent decline) (Brunkhurst 2012, unpublished 
data).
    The northern long-eared bat is becoming less common on the Vermont 
landscape as well. Pre-WNS, the species was the second most common bat 
species in the State; however, it is now one of the least likely to be 
encountered, with the change in effort to capture one bat increasing by 
nearly 13 times, and approximately a 94-percent overall reduction in 
captures in mist-net surveys (Darling and Smith 2011, unpublished 
data). In eastern New York, captures of northern long-eared bats have 
declined dramatically, approximately 93 percent, for the species from 
pre-WNS (Herzog 2012, unpublished data). Prior to discovery of WNS in 
West Virginia, northern long-eared bat mist-net captures comprised 41 
percent of all captures and 24 percent post-WNS (2010) and at a rate of 
23 percent of historical rates (Francl et al. 2012, pp. 35-36). In 
addition, pregnancy peaked more than 2 weeks earlier post-WNS than pre-
WNS (May 20 versus June 7, respectively) and the proportion of 
juveniles declined by more than half in mid-August; it is unclear if 
this change will have population-level effects on the species at this 
time (Francl et al. 2012, p. 36). Ford et al. (2011, p. 127) conducted 
summer acoustic surveys on Fort Drum, New York, from 2003-2010, 
including pre-WNS (2003-2008) and post-WNS (2008-2010). Although 
activity still rose from early summer to late summer for northern long-
eared bats, the overall activity levels for the species declined from 
pre- to post-WNS (Ford et al. 2011, pp. 129-130). Similarly, Nagel and 
Gates (2012, p. 5) reported a 78-percent decrease in northern long-
eared bat passes (as compared to a 63-percent increase in the number of 
eastern small-footed bats mentioned above) during acoustic surveys 
between 2010 and 2012 in western Maryland. ``Due to the greatest 
recorded decline in regional hibernacula counts (Turner et al. 2011), 
the northern long-eared bat is of particular concern (to researchers in 
Pennsylvania)'' (Turner 2013, unpublished data). Therefore, researchers 
in Pennsylvania selected two sites to study in 2010 and 2011, where 
pre-WNS swarm trapping had previously been conducted. The capture rates 
at the first site declined by 95 percent and at the second site by 97 
percent, which corroborates documented interior hibernacula declines 
(Turner 2013 unpublished data; Turner et al. 2011, p. 18).
    Although northern long-eared bats are known to awaken from a state 
of torpor sporadically throughout the winter and move between 
hibernacula (Griffin 1940, p. 185; Whitaker and Rissler 1992b, p. 131; 
Caceres and Barclay 2000 pp. 2-3), they have not been observed roosting 
regularly outside of caves and mines during the winter, as species that 
are less susceptible to WNS (e.g., big brown bat) have. Northern long-
eared bats may be more susceptible to evaporative water loss (and 
therefore more susceptible to WNS) due to their propensity to roost in 
the most humid parts of the hibernacula (Cryan et al. 2010, p. 4). As 
described in the Hibernation section above, northern long-eared bats 
roost in areas within hibernacula that have higher humidity, possibly 
leading to higher rates of infection, as Langwig et al. (2012a, p. 
1055) found with Indiana bats. Also, northern long-eared bats prefer 
cooler temperatures within hibernacula: 0 to 9 [deg]C (32 to 48 [deg]F) 
(Raesly and Gates 1987, p. 18; Caceres and Pybus 1997, p. 2; Brack 
2007, p. 744), which are within the optimal growth limits of Gyomyces 
destructans (5 to 10 [deg]C (41 to 50 [deg]F)) (Blehert et al. 2009, p. 
227).
    The northern long-eared bat may also spend more time in hibernacula 
than other species that are less susceptible (e.g., eastern small-
footed bat (see Effects of White-nose Syndrome on the Eastern Small-
footed Bat section, above)), which allows more time for the fungus to 
infect bats and grow; northern long-eared bats enter the cave or mine 
in October or November (although they may enter as early as August) and 
leave the hibernaculum in March or April (Caire et al. 1979, p. 405; 
Whitaker and Hamilton 1998, p. 100; Amelon and Burhans 2006, p. 72). 
Furthermore, the northern long-eared bat occasionally roosts in 
clusters or in the same hibernacula as other bat species that are also 
susceptible to WNS (see Hibernation section, above); therefore, 
northern long-eared bats may have increased susceptibility to bat-to-
bat transmission of WNS.
    Given the observed dramatic population declines attributed to WNS, 
as described above, we are greatly concerned about this species' 
persistence where WNS has already spread. The area currently affected 
by WNS constitutes the core of the northern long-eared bat's range, 
where the species was most common prior to WNS; the species is less 
common in the southern and western parts of its range and is considered 
to be rare in the northwestern part of its range (Caceres and Barclay 
2000, p. 2; Harvey 1992, p. 35), the areas where WNS has not yet been 
detected. Furthermore, the rate at which WNS has spread has been rapid; 
it was first detected in New York in 2006, and has spread west at least 
as far as Illinois and Missouri, south as far as Georgia and South 
Carolina, and north as far as southern Quebec and Ontario as of 2013. 
Although this spread rate may slow or have reduced effects in the more 
southern and western parts of the species' range (Frick and Kilpatrick 
2013, pers. comm.), general agreement is that WNS will indeed spread 
throughout the United States (Hallam et al. 2011, p. 8; Maher et al. 
2012, pp. 4-5). WNS has already had a substantial effect on northern 
long-eared bats in the core of its range and is likely to spread 
throughout the species' entire range within a short time; thus we 
consider it to be the predominant threat to the species rangewide.
Other Diseases
    Infectious diseases observed in North American bat populations 
include rabies, histoplasmosis, St. Louis encephalitis, and Venezuelan 
equine encephalitis (Burek 2001, p. 519; Rupprecht et al. 2001, p. 14; 
Yuill and Seymour 2001, pp. 100, 108). Rabies is the most studied 
disease of bats, and can lead to mortality, although antibody evidence 
suggests that some bats may

[[Page 61066]]

recover from the disease (Messenger et al. 2003, p. 645) and retain 
immunological memory to respond to subsequent exposures (Turmelle et 
al. 2010, p. 2364). Bats are hosts of rabies in North America 
(Rupprecht et al. 2001, p. 14), accounting for 24 percent of all wild 
animal cases reported during 2009 (Centers for Disease Control and 
Prevention 2011). Although rabies is detected in up to 25 percent of 
bats submitted to diagnostic labs for testing, less than 1 percent of 
bats sampled randomly from wild populations test positive for the virus 
(Messenger et al. 2002, p. 741). Eastern small-footed and northern 
long-eared bats are among the species reported positive for rabies 
virus infection (Constantine 1979, p. 347; Burnett 1989, p. 12; Main 
1979, p. 458); however, rabies is not known to have appreciable effects 
to either species.
    Histoplasmosis has not been associated with eastern small-footed 
bats or northern long-eared bats and may be limited in these species 
compared to other bats that form larger aggregations with greater 
exposure to guano-rich substrate (Hoff and Bigler 1981, p. 192). St. 
Louis encephalitis antibody and high concentrations of Venezuelan 
equine encephalitis virus have been observed in big brown bats and 
little brown bats (Yuill and Seymour 2001, pp. 100, 108), although data 
are lacking on the prevalence of these viruses in eastern small-footed 
bats. Eastern equine encephalitis has been detected in northern long-
eared bats (Main 1979, p. 459), although no known population declines 
have been found due to presence of the virus. Northern long-eared bats 
are also known to carry a variety of pests including chiggers, mites, 
bat bugs, and internal helminthes (Caceres and Barclay 2000, p. 3). 
None of these diseases or pests, however, has caused the record level 
of bat mortality like that observed since the emergence of WNS.
Predation
    Typically, animals such as owls, hawks, raccoons, skunks, and 
snakes prey upon bats, although a limited number of animals consume 
bats as a regular part of their diet (Harvey et al. 1999, p. 13). 
Eastern small-footed and northern long-eared bats experience a very 
small amount of predation; therefore, predation does not appear to be a 
major cause of mortality (Caceres and Pybus 1997, p. 4; Whitaker and 
Hamilton 1998, p. 101).
    Predation has been observed at a limited number of hibernacula 
within the range of the northern long-eared and eastern small-footed 
bats. Of the State and Federal agency responses received pertaining to 
eastern small-footed bat hibernacula and the threat of predation, only 
8 out of 80 responses (10 percent) reported hibernacula as being prone 
to predation. For northern long-eared bats, 1 hibernacula in Maine, 3 
in Maryland (2 of which were due to feral cats), 1 in Minnesota, and 10 
in Vermont were reported as being prone to predation. In one instance, 
domestic cats were observed killing bats at a hibernaculum used by 
northern long-eared bat and eastern small-footed bat in Maryland, 
although the species of bat killed was not identified (Feller 2011, 
unpublished data). Turner (1999, personal observation) observed a snake 
(species unknown) capture an emerging Virginia big-eared bat 
(Corynorhinus townsendii virginianus) in West Virginia. The bat was 
captured in flight while the snake was perched along the top of a bat 
gate at the cave's entrance. Tuttle (1979, p. 11) observed (eastern) 
screech owls (Otus asio) capturing emerging gray bats.
    Northern long-eared bats are known to be affected to a small degree 
by predators at summer roosts. Avian predators, such as owls and 
magpies, are known to successfully take individual bats as they roost 
in more open sites, although this most likely does not have an effect 
on the overall population size (Caceres and Pybus 1997, p. 4). In 
addition, Perry and Thill (2007, p. 224) observed a black rat snake 
(Elaphe obsoleta obsoleta) descending from a known maternity colony 
snag in the Ouachita Mountains of Arkansas. In summary, since bats are 
not a primary prey source for any known natural predators, it is 
unlikely that predation has substantial effects on either species at 
this time.
Conservation Efforts To Reduce Disease or Predation
    As mentioned above, WNS is a disease that is responsible for 
unprecedented mortality in some hibernating bats in the northeast, like 
the northern long-eared bat, and it continues to spread throughout the 
range of the northern long-eared bat and eastern small-footed bat. 
Although conservation efforts have been undertaken to help reduce the 
spread of the disease through human-aided transmission, these efforts 
have only been in place for a few years and it is too early to 
determine how effective they are in decreasing the rate of spread. In 
2008, the Service, along with several other State and Federal agencies, 
initiated a national plan (A National Plan for Assisting States, 
Federal Agencies, and Tribes in Managing White-Nose Syndrome in Bats 
(WNS National Plan, https://static.whitenosesyndrome.org/sites/default/files/white-nose_syndrome_national_plan_may_2011.pdf)) that 
details the elements critical to investigating and managing WNS, along 
with identifying actions and roles for agencies and entities involved 
with the effort (Service 2011, p. 1). In addition to bat-to-bat 
transmission of the disease, fungal spores can be transmitted by humans 
(USGS National Wildlife Health Center, Wildlife Health Bulletin 2011-
05). Therefore, the WNS Decontamination Team (a sub-group under the WNS 
National Plan), created a decontamination protocol (Service 2012, p. 2) 
that provides specific procedures to ensure human transmission risk to 
bats is minimized.
    The Service also issued an advisory calling for a voluntary 
moratorium on all caving activity in States known to have hibernacula 
affected by WNS, and all adjoining States, unless conducted as part of 
an agency-sanctioned research or monitoring project (Service 2009). The 
Western Bat Working Group has also developed a White-nose Syndrome 
Action Plan, a comprehensive strategy to prevent the spread of WNS, 
that covers States currently outside the range of WNS (Western Bat 
Working Group 2010, p. 1-11). Although the majority of State and 
Federal agencies and tribes within the northern long-eared bat's and 
eastern small-footed bat's ranges have adopted the recommendations and 
protocols in the WNS National Plan, these are not mandatory or 
required. For example, in Virginia, the decontamination procedures are 
recommended for cavers; however, although the Virginia Department of 
Game and Inland Fisheries currently has closed the caves on the 
agencies' properties, they are reviewing this policy in light of the 
extensive spread of WNS throughout the State.
    The NPS is currently updating their cave management plans (for 
parks with caves) to include actions to minimize the risk of WNS 
spreading to uninfected caves. These actions include WNS education, 
screening visitors for disinfection, and closure of caves if necessary 
(NPS 2013, https://www.nature.nps.gov/biology/WNS). In April 2009, all 
caves and mines on U.S. Forest Service lands in the Eastern Region were 
closed on an emergency basis in response to the spread of WNS. Eight 
National Forests in the Eastern Region contain caves or mines that are 
used by bats; caves and mines on seven of these National Forests 
(Allegheny, Hoosier, Ottawa, Mark Twain, Mononqahela, Shawnee, and 
Wayne) are currently closed, and no closure is

[[Page 61067]]

needed for the one mine on the eighth National Forest (Green Mountain) 
because it is already gated with a bat-friendly structure. Forest 
supervisors continue to evaluate the most recent information on WNS to 
inform decisions regarding extending cave and mine closures for the 
purpose of limiting the spread of WNS (U.S. Forest Service 2013, https://www.fs.fed.us/r9/wildlife/wildlife/bats.php). Caves and mines on U.S. 
Forest Service lands in the Rocky Mountain Region were closed on an 
emergency basis in 2010, in response to WNS, but since then have been 
reopened, with some exceptions (U.S. Forest Service 2013, https://www.fs.usda.gov/detail/r2/home/?cid=stelprdb5319926). In place of the 
emergency closures, the Rocky Mountain Region will implement an 
adaptive management strategy that will require registration to access 
an open cave, prohibit use of clothing or equipment used in areas where 
WNS is found, require decontamination procedures prior to entering any 
and all caves, and close all known cave hibernacula during the winter 
hibernation period. Although the above mentioned WNS-related 
conservation measures may help reduce or slow the spread of the 
disease, these efforts are not currently enough to ameliorate the 
population-level effect to the northern long-eared bat.
Summary of Disease and Predation
    In summary, while populations of several species of hibernating 
bats (e.g., little brown bat, Indiana bat, northern long-eared bat, 
tri-colored bat) have experienced mass mortality due to WNS, 
populations of the eastern small-footed bat appear to be stable, and if 
they are in decline, the level of impact is not discernible at this 
time. Summer monitoring data are scarce, and the little data we have 
are inconclusive. However, based on the best available scientific 
information, we conclude that disease does not have an appreciable 
effect on the eastern small-footed bat.
    Unlike the eastern small-footed bat, the northern long-eared bat 
has experienced a sharp decline, estimated at approximately 99 percent 
(from hibernacula data), in the northeastern portion of its range, due 
to the emergence of WNS. Summer survey data have confirmed rates of 
decline observed in northern long-eared bat hibernacula data post-WNS. 
The species is highly susceptible to WNS where the disease currently 
occurs in the East, and there is no reason to expect that western 
populations will be resistant to the disease. Thus, we expect that 
similar declines as seen in the East will be experienced in the future 
throughout the majority of the species' range. This is currently viewed 
as the predominant threat to the species, and if WNS had not emerged or 
was not affecting northern long-eared bat populations to the level that 
it has, we presume the species would not be declining to the degree 
observed.
    As bats are not a primary prey source for any known natural 
predators, it is unlikely that predation is significantly affecting 
either species at this time.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    Under this factor, we examine whether existing regulatory 
mechanisms are inadequate to address the threats to the species 
discussed under the other factors. Section 4(b)(1)(A) of the Act 
requires the Service to take into account ``those efforts, if any, 
being made by any State or foreign nation, or any political subdivision 
of a State or foreign nation, to protect such species. . . .'' In 
relation to Factor D under the Act, we interpret this language to 
require the Service to consider relevant Federal, State, and tribal 
laws, regulations, and other such mechanisms that may minimize any of 
the threats we describe in threat analyses under the other four 
factors, or otherwise enhance conservation of the species. We give 
strongest weight to statutes and their implementing regulations and to 
management direction that stems from those laws and regulations. An 
example would be State governmental actions enforced under a State 
statute or constitution, or Federal action under statute.
    Having evaluated the significance of the threat as mitigated by any 
such conservation efforts, we analyze under Factor D the extent to 
which existing regulatory mechanisms are inadequate to address the 
specific threats to the species. Regulatory mechanisms, if they exist, 
may reduce or eliminate the effects from one or more identified 
threats. In this section, we review existing State, Federal, and local 
regulatory mechanisms to determine whether they effectively reduce or 
remove threats to the eastern small-footed bat or northern long-eared 
bat.
    No existing regulatory mechanisms have been designed to protect the 
species against WNS, the primary threat to the northern long-eared bat; 
thus, despite regulatory mechanisms that are currently in place, the 
species is still at risk. There are, however, some mechanisms in place 
to provide some protection from other factors that may act cumulatively 
with WNS. As such, the discussion below provides a few examples of such 
existing regulatory mechanisms, but is not a comprehensive list.
Federal
    Several laws and regulations help Federal agencies protect bats on 
their lands, such as the Federal Cave Resources Protection Act (16 
U.S.C. 4301 et seq.) that protects caves on Federal lands and National 
Environmental Policy Act (42 U.S.C. 4321 et seq.) review, which serves 
to mitigate effects to bats due to construction activities on federally 
owned lands. The NPS has additional laws, policies, and regulations 
that protect bats on NPS units, including the NPS Organic Act od 1916 
(16 U.S.C. 1 et seq.), NPS management policies (related to exotic 
species and protection of native species), and NPS policies related to 
caves and karst systems (provides guidance on placement of gates on 
caves not only to address human safety concerns but also for the 
preservation of sensitive bat habitat) (Plumb and Budde 2011, 
unpublished data). Even if a bat species is not listed under the 
Endangered Species Act, the NPS works to minimize effects to the 
species. In addition, the NPS Research Permitting and Reporting System 
tracks research permit applications and investigator annual reports, 
and NPS Management Policies require non-NPS studies conducted in parks 
to conform to NPS policies and guidelines regarding the collection of 
bat data (Plumb and Budde 2011, unpublished data).
    The northern long-eared bat is considered a ``sensitive species'' 
throughout U.S. Forest Service's Eastern Region (USDA Forest Service 
2012). As such, the northern long-eared bat must receive, ``special 
management emphasis to ensure its viability and to preclude trends 
toward endangerment that would result in the need for Federal listing. 
There must be no effects to sensitive species without an analysis of 
the significance of adverse effects on the populations, its habitat, 
and on the viability of the species as a whole. It is essential to 
establish population viability objectives when making decisions that 
would significantly reduce sensitive species numbers'' (Forest Service 
Manual (FSM) 2672.1).
State
    The eastern small-footed bat is State-listed as endangered in 
Maryland and New Hampshire; State-listed as threatened in Kentucky, 
Pennsylvania, South Carolina, and Vermont; and considered as a species 
of special concern in Connecticut, Delaware,

[[Page 61068]]

Georgia, Indiana, Massachusetts, Missouri, New Jersey, New York, North 
Carolina, Ohio, Oklahoma, Tennessee, Virginia, and West Virginia. The 
level of protection provided under these laws varies by State, but most 
prohibit take, possession, or transport of listed species. For example, 
in Maryland, a person may not take, possess, transport, export, 
process, sell, offer for sale, or ship nongame wildlife (MD Code, 
Natural Resources, sec. 10-2A-01-09); however, effects to summer 
roosting habitat and direct mortality from wind energy development 
projects under 70 Megawatts (MW) are currently exempted from 
protections offered to the eastern small-footed bat (Feller 2011, 
unpublished data). In Pennsylvania, however, a House Bill proposed in 
the General Assembly, if passed, would not allow any ``commonwealth 
agency to take action to classify or consider wildlife, flora or fauna 
as threatened or endangered unless the wildlife, flora or fauna is 
protected under the Endangered Species Act of 1973'' (General Assembly 
of Pennsylvania 2013, p. 2).
    The northern long-eared bat is listed in very few of the States 
within the species' range. The northern long-eared bat is listed as 
endangered under the Massachusetts endangered species act, under which 
all listed species are, ``protected from killing, collecting, 
possessing, or sale and from activities that would destroy habitat and 
thus directly or indirectly cause mortality or disrupt critical 
behaviors.'' In addition, listed animals are specifically protected 
from activities that disrupt nesting, breeding, feeding, or migration 
(Massachusetts Division of Fisheries and Wildlife 2012, unpublished 
document). In Wisconsin, all cave bats, including the northern long-
eared bat, were listed as threatened in the State in 2011, due to 
previously existing threats and the impending threat of WNS (Redell 
2011, pers. comm.). Certain development projects (e.g., wind energy), 
however, are excluded from regulations in place to protect the species 
in Wisconsin (Wisconsin Department of Natural Resources, unpublished 
document, 2011, p. 4). The northern long-eared bat is considered as 
some form of species of concern in 17 States: ``Species of Greatest 
Concern'' in Alabama and Rhode Island; ``Species of Greatest 
Conservation Need'' in Delaware, Iowa, and Vermont; ``Species of 
Concern'' in Ohio and Wyoming; ``Rare Species of Concern'' in South 
Carolina; ``Imperiled'' in Oklahoma; ``Critically Imperiled'' in 
Louisiana; and ``Species of Special Concern'' in Indiana, Maine, 
Minnesota, New Hampshire, North Carolina, Pennsylvania, and South 
Carolina.
    In the following States, there is either no State protection law or 
the northern long-eared bat is not protected under the existing law: 
Arkansas, Connecticut, Florida, Georgia, Illinois, Kansas, Kentucky, 
Maryland, Mississippi, Missouri, Montana, Nebraska, New Jersey, New 
York, North Dakota, Tennessee, Virginia, and West Virginia. In 
Kentucky, although the northern long-eared bat does not have a State 
listing status, it is considered protected from take under Kentucky 
State law; however, since greater than 95 percent of hibernacula in 
Kentucky are privately owned, cave closures are not often possible to 
enforce (Hemberger 2011, unpublished data).
    Wind energy development regulation varies by State within the 
northern long-eared bat's and eastern small-footed bat's ranges. For 
example, in Virginia, although there are not currently any wind energy 
developments in the State, new legislation requires mitigation for bats 
with the objective of reducing fatalities. As part of the regulation, 
operators are required to ``measure the efficacy'' of mitigation 
(Reynolds 2011 unpublished data). In Vermont, all wind projects are 
required to conduct bat mortality surveys, and at least 2 of the 3 
currently permitted projects in the State include application of 
operational adjustments (curtailment) to reduce bat fatalities (Smith 
2011, unpublished data).
Summary of Inadequacy of Existing Regulatory Mechanisms
    No existing regulatory mechanisms have been designed to protect the 
species against WNS, the primary threat to the northern long-eared bat. 
Therefore, despite regulatory mechanisms that are currently in place 
for the northern long-eared bat, the species is still at risk, 
primarily due to WNS, as discussed under Factor C.

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence

Wind Energy Development
    In general, bats are killed in significant numbers by utility-scale 
(greater than or equal to 0.66 megawatt (MW)) wind turbines along 
forested ridge tops in the eastern United States (Johnson 2005, p. 46; 
Arnett et al. 2008, p. 63). The majority of bats killed include 
migratory foliage-roosting species: the hoary bat (Lasiurus cinereus) 
and eastern red bat (Lasiurus borealis); migratory tree and cavity-
roosting silver-haired bats (Lasionycteris noctivagans); and tri-
colored bats (Arnett et al. 2008, p. 64).
    Three effects may explain proximate causes of bat fatalities at 
wind turbines: (1) Bats collide with turbine towers, (2) bats collide 
with moving blades, or (3) bats suffer internal injuries (barotrauma) 
after being exposed to rapid pressure changes near the trailing edges 
and tips of moving blades (Cryan and Barclay 2009, p. 1331). It appears 
that barotrauma may be responsible for some deaths observed at wind-
energy development sites. For example, nearly half of the 1,033 bat 
carcasses discovered over a 2-year study by Klug and Baerwald (2010, p. 
15) had no fatal external injuries, and over 90 percent of those 
necropsied had internal injuries consistent with barotrauma (Baerwald 
et al. 2008, pp. 695-696). However, another study found that bone 
fractures from direct collision with turbine blades contributed to 74 
percent of bat deaths, and therefore suggest that skeletal damage from 
direct collision with turbine blades is a major cause of fatalities for 
bats killed by wind turbines (Grodsky et al. 2011, p. 920). The authors 
suggest that these injuries can lead to an underestimation of bat 
mortality at wind energy facilities due to delayed lethal effects 
(Grodsky et al. 2011, p. 924). Lastly, the authors also note that the 
surface and core pressure drops behind the spinning turbine blades are 
high enough (equivalent to sound levels that are 10,000 times higher in 
energy density than the threshold of pain in humans (Cmiel et al. 
2004)) to cause significant ear damage to bats flying near wind 
turbines (Grodsky et al. 2011, p. 924). Bats crippled by ear damage 
would have a difficult time navigating and foraging, since both of 
these functions depend on the bats' ability to echolocate (Grodsky et 
al. 2011, p. 924).
    Wind projects have been constructed in areas within a large portion 
of the ranges of eastern small-footed bats and northern long-eared 
bats, suggesting these species may be exposed to the risk of turbine-
related mortality. However, as of 2011, only two eastern small-footed 
bat and 13 northern long-eared bat fatalities were recorded from North 
American wind-energy facilities, representing less than 0.1 percent and 
0.2 percent of the total bat mortality, respectively (American Wind 
Energy Association 2011, p. 18). Because eastern small-footed bats fly 
slowly and close to the ground (Davis et al. 1965, p. 683), they may be 
less susceptible to mortality caused by the operation of wind turbines.

[[Page 61069]]

    The threat level posed by wind development to northern long-eared 
and eastern small-footed bats throughout their ranges varies. For 
example, in Illinois, wind energy development is viewed as a large 
threat to northern long-eared bats, especially during migration. 
Although the species is not considered a long-distance migrant, even 
limited migration distances between summer and winter habitats pose a 
risk to the northern long-eared bat in Illinois, due to the 
increasingly large line of wind farms across most of the central 
portion of the State (Kath 2012, pers. comm.). In 2012, 7 to 10 wind 
farms were in operation, and at least as many are planned. Further, 
northern long-eared bats have been found in pre-construction surveys 
for many of the wind farms (both planned and operational) (Kath 2012, 
pers. comm.). In Minnesota, wind energy development is moving at a 
rapid pace, and is one of the reasons State wildlife agency officials 
are concerned about the species' status in the State (Baker 2011, pers. 
comm.). In many States, such as Maryland, New Hampshire, South 
Carolina, and Vermont, wind energy projects have just recently been 
completed or are in the process of being installed; therefore, the 
level of mortality to northern long-eared bats and eastern small-footed 
bats has yet to be seen (Brunkhurst 2012, pers. comm.; Bunch 
2011,unpublished data; Feller 2011, unpublished data; Smith 2011, 
unpublished data). Vermont currently has three permitted wind energy 
facilities in the State (the first of which is currently under 
construction), from which State officials see limited potential that 
northern long-eared bat fatalities will occur (Smith 2011, unpublished 
data), likely due to the current low population of the species in the 
State. We conclude that there may be adverse effects posed by wind 
energy development to northern long-eared bats and eastern small-footed 
bats; however, there is no evidence suggesting effects from wind energy 
development in itself have led to population declines in either 
species.
Climate Change
    Our analyses under the Act include consideration of ongoing and 
projected changes in climate. The terms ``climate'' and ``climate 
change'' are defined by the Intergovernmental Panel on Climate Change 
(IPCC). The term ``climate'' refers to the mean and variability of 
different types of weather conditions over time, with 30 years being a 
typical period for such measurements, although shorter or longer 
periods also may be used (IPCC 2007a, p. 78). The term ``climate 
change'' thus refers to a change in the mean or variability of one or 
more measures of climate (e.g., temperature or precipitation) that 
persists for an extended period, typically decades or longer, whether 
the change is due to natural variability, human activity, or both (IPCC 
2007a, p. 78).
    Scientific measurements spanning several decades demonstrate that 
changes in climate are occurring, and that the rate of change has been 
faster since the 1950s. Examples include warming of the global climate 
system, and substantial increases in precipitation in some regions of 
the world and decreases in other regions. (For these and other 
examples, see IPCC 2007a, p. 30; Solomon et al. 2007, pp. 35-54, 82-
85). Results of scientific analyses presented by the IPCC show that 
most of the observed increase in global average temperature since the 
mid-20th century cannot be explained by natural variability in climate, 
and is ``very likely'' (defined by the IPCC as 90 percent or higher 
probability) due to the observed increase in greenhouse gas (GHG) 
concentrations in the atmosphere as a result of human activities, 
particularly carbon dioxide emissions from use of fossil fuels (IPCC 
2007a, pp. 5-6 and figures SPM.3 and SPM.4; Solomon et al. 2007, pp. 
21-35). Further confirmation of the role of GHGs comes from analyses by 
Huber and Knutti (2011, p. 4), who concluded it is extremely likely 
that approximately 75 percent of global warming since 1950 has been 
caused by human activities.
    Scientists use a variety of climate models, which include 
consideration of natural processes and variability, as well as various 
scenarios of potential levels and timing of GHG emissions, to evaluate 
the causes of changes already observed and to project future changes in 
temperature and other climate conditions (e.g., Meehl et al. 2007, 
entire; Ganguly et al. 2009, pp. 11555, 15558; Prinn et al. 2011, pp. 
527, 529). All combinations of models and emissions scenarios yield 
very similar projections of increases in the most common measure of 
climate change, average global surface temperature (commonly known as 
global warming), until about 2030. Although projections of the 
magnitude and rate of warming differ after about 2030, the overall 
trajectory of all the projections is one of increased global warming 
through the end of this century, even for the projections based on 
scenarios that assume that GHG emissions will stabilize or decline. 
Thus, there is strong scientific support for projections that warming 
will continue through the 21st century, and that the magnitude and rate 
of change will be influenced substantially by the extent of GHG 
emissions (IPCC 2007a, pp. 44-45; Meehl et al. 2007, pp. 760-764 and 
797-811; Ganguly et al. 2009, pp. 15555-15558; Prinn et al. 2011, pp. 
527, 529). (See IPCC 2007b, p. 8, for a summary of other global 
projections of climate-related changes, such as frequency of heat waves 
and changes in precipitation. Also see IPCC 2011 (entire) for a summary 
of observations and projections of extreme climate events.)
    Various changes in climate may have direct or indirect effects on 
species. These effects may be positive, neutral, or negative, and they 
may change over time, depending on the species and other relevant 
considerations, such as interactions of climate with other variables 
(e.g., habitat fragmentation) (IPCC 2007, pp. 8-14, 18-19). Identifying 
likely effects often involves aspects of climate change vulnerability 
analysis. Vulnerability refers to the degree to which a species (or 
system) is susceptible to, and unable to cope with, adverse effects of 
climate change, including climate variability and extremes. 
Vulnerability is a function of the type, magnitude, and rate of climate 
change and variation to which a species is exposed, its sensitivity, 
and its adaptive capacity (IPCC 2007a, p. 89; see also Glick et al. 
2011, pp. 19-22). There is no single method for conducting such 
analyses that applies to all situations (Glick et al. 2011, p. 3). We 
use our expert judgment and appropriate analytical approaches to weigh 
relevant information, including uncertainty, in our consideration of 
various aspects of climate change.
    As is the case with all stressors that we assess, even if we 
conclude that a species is currently affected or is likely to be 
affected in a negative way by one or more climate-related effects, it 
does not necessarily follow that the species meets the definition of an 
``endangered species'' or a ``threatened species'' under the Act. If a 
species is listed as endangered or threatened, knowledge regarding the 
vulnerability of the species to, and known or anticipated impacts from, 
climate-associated changes in environmental conditions can be used to 
help devise appropriate strategies for its recovery.
    The unique natural history traits of bats and their susceptibility 
to local temperature, humidity, and precipitation patterns make them an 
early warning system for effects of climate change in regional 
ecosystems (Adams and Hayes 2008, p. 1120). Climate change is expected 
to alter seasonal ambient temperatures and

[[Page 61070]]

precipitation patterns across regions (Adams and Hayes 2008, p. 1115). 
The ability of successful reproductive effort in female insectivorous 
bats is related directly to roost temperatures and water availability 
(Adams and Hayes 2008, p. 1116). Adams and Hayes (2008, p. 1120) 
predict an overall decline in bat populations in the western United 
States from reduced regional water storage caused by climate warming. 
In comparison, the northeast United States is projected to see a steady 
increase in annual winter precipitation, although a much greater 
proportion is expected to fall as rain rather than as snow. Overall, 
little change in summer rainfall is expected, although projections are 
highly variable (Frumhoff et al. 2007, p. 8). Based on this model, 
water availability should not be a limiting factor to bats in the 
northeast United States.
    Climate change may result in warmer winters, which could lead to a 
reduced period of hibernation, increased winter activity, and reduced 
reliance on the relatively stable temperatures of underground 
hibernation sites (Jones et al. 2009, p. 99). Hibernation sites chosen 
by eastern small-footed bats (e.g., under rocks) may be even more 
susceptible to temperature fluctuations, which may lead to energy 
depletion that reduces winter survival (Rodenhouse et al. 2009, p. 
251). An earlier spring would presumably result in a shorter 
hibernation period and the earlier appearance of foraging bats (Jones 
et al. 2009, p. 99). An earlier emergence from hibernation may have no 
detrimental effect on population size if sufficient food is available 
(Jones et al. 2009, p. 99); however, predicting future insect 
population dynamics and distributions is complex (Bale et al. 2002, p. 
6). Alterations in precipitation, stream flow, and soil moisture could 
influence insect populations in such a way as to potentially alter food 
availability for bats (Rodenhouse et al. 2009, p. 250).
    Warmer winter temperatures may also disrupt bat reproductive 
physiology. Both eastern small-footed bats and northern long-eared bats 
breed in the fall, and spermatozoa are stored in the uterus of 
hibernating females until spring ovulation. If bats experience warm 
conditions they may arouse from hibernation prematurely, ovulate, and 
become pregnant (Jones et al. 2009, p. 99). Given this dependence on 
external temperatures, climate change is likely to affect the timing of 
reproductive cycles (Jones et al. 2009, p. 99), but whether these 
effects would be to the detriment of the species is largely unknown. A 
shorter hibernation period and warmer winter temperatures may lead to 
less exposure and slower spread of WNS or persistence of the fungus, 
which would likely benefit both species. However, the rapid rate at 
which WNS is affecting the species is on a much quicker time scale than 
are the changes associated with climate change. Thus, longer-term 
effects of climate change are unlikely to have an impact on the short-
term effects of WNS. Although we do have information that suggests that 
climate change may impact both the northern long-eared bat and eastern 
small-footed bat and bats in general, we do not have any evidence 
suggesting that climate change in itself has led to population declines 
in either species.
Contaminants
    Effects to bats from contaminant exposure have likely occurred and 
gone, for the most part, unnoticed among bat populations (Clark and 
Shore 2001, p. 204). Contaminants of concern to insectivorous bats like 
the eastern small-footed and northern long-eared bats include 
organochlorine pesticides, organophosphate, carbamate and neonicotinoid 
insecticides, polychlorinated biphenyls and polybrominated diphenyl 
ethers (PBDEs), pyrethroid insecticides, and inorganic contaminants 
such as mercury (Clark and Shore 2001, pp. 159-214).
    Organochlorine pesticides (e.g., DDT, chlordane) persist in the 
environment due to lipophilic (fat-loving) properties, and therefore 
readily accumulate within the fat tissue of bats. Because insectivorous 
bats have high metabolic rates, associated with flight and small size, 
their food intake increases the amount of organochlorines available for 
concentration in the fat (Clark and Shore 2001, p. 166). Because bats 
are long-lived, the potential for bioaccumulation is great, and effects 
on reproduction and populations have been documented (Clark and Shore 
2001, pp. 181-190). In maternity colonies, young bats appear to be at 
the greatest risk of mortality. This is because organochlorines become 
concentrated in the fat of the mother's milk and these chemicals 
continually and rapidly accumulate in the young as they nurse (Clark 
1988, pp. 410-411).
    In addition to indirect effects of contaminants on bats via prey 
consumption, documented cases of population-level effects involve 
direct application of pesticides to bats or their roosts. For example, 
when a mixture of DDT and chlordane was applied to little brown bats 
and their roost site, mortality from exposure was observed (Kunz et al. 
1977, p. 478). Most organochlorine pesticides have been banned in the 
United States and have largely been replaced by organophosphate 
insecticides, which are generally short-lived in the environment and do 
not accumulate in food chains; however, risk of exposure is still 
possible from direct exposure from spraying or ingesting insects that 
have recently been sprayed but have not died, or both (Clark 1988, p. 
411). Organophospahate and carbamate insecticides are acutely toxic to 
mammals. Also, some organophosphates may be stored in fat tissue and 
contribute to ``organophosphate-induced delayed neuropathy'' in humans 
(USEPA 2013, p. 44).
    Bats are less sensitive to organophosphate insecticides than birds 
in regards to acute toxicity, but many bats lose their motor 
coordination from direct application and are unlikely to survive in the 
wild in an incapacitated state lasting over 24 hours (Plumb and Budde 
2011, unpublished data). Bats may be exposed to organophosphate and 
carbamate insecticides in regions where methyl parathion is applied in 
cotton fields and where malathion is used for mosquito control (Plumb 
and Budde 2011, unpublished data). The organophosphate, chlorpyrifos, 
has high fat solubility and is commonly used on crops such as corn, 
soybeans (van Beelen 2000, p. 34 of Appendix 2; https://water.usgs.gov/nawqa/pnsp/usage/maps/show_map.php?year=2009&map=CHLORPYRIFOS&hilo=L).
    The neonicotinoids have been found to cause oxidative stress, 
neurological damage and possible liver damage in rats and immune 
suppression in mice (https://www.sciencedirect.com/science/article/pii/S0048357512001617 Badgujar et al. 2013, p. 408; Duzguner 2012, p. 58; 
Kimura-Kuroda et al. 2011, p. 381), Due to information indicating that 
there is a link between neonicotinoids used in agriculture and a 
decline in bee numbers, the European Union proposed a two year ban on 
the use of the neonocotinoids, thiamethoxam, imidacloprid and 
clothianidin on crops attractive to honeybees, beginning in December of 
2013 (https://www.lawbc.com/regulatory-developments/entry/proposal-for-restriction-of-neonicotinoid-products-in-the-eu/).
    The more recently developed ``third generation'' of pyrethroids 
have acute oral toxicities rivaling the toxicity of organophosphate, 
carbamate and organochlorine pesticides. These pyrethroids include 
esfenvalerate, deltamethrin, bifenthrin, tefluthrin, flucythrinate, 
cyhalothrin and fenpropathrin (Mueller-Beilschmidt 1990, p. 32). 
Pyrethroids are

[[Page 61071]]

increasingly used in the United States, and some of these compounds 
have very high fat solubility (e.g., bifenthrin, cypermethrin) (van 
Beelen 2000, p. 34 of Appendix 2).
    Like the organochlorine pesticides, PCBs and PBDEs are highly 
lipophilic and therefore readily accumulate in insectivorous bats. 
Outside of laboratory experiments, there is no conclusive evidence that 
bats have been killed by PCBs, although effects on reproduction have 
been observed (Clark and Shore 2001, pp. 192-194).
    In New Hampshire, to limit the amount of plant material growing on 
the rock slope of the Surry Mountain Reservoir, the U.S. Army Corps of 
Engineers spray the rock slope with herbicide; this site is an eastern 
small-footed bat summer roosting site (Veilleux and Reynolds 2006, p. 
331). It is unknown whether the direct application of herbicide on the 
roost area reduces the roost quality or causes mortality of adult bats, 
young bats, or both.
    Eastern small-footed bats and northern long-eared bats forage on 
emergent insects and can be characterized as occasionally foraging over 
water (Yates and Evers 2006, p. 5), and therefore are at risk of 
exposure to bioaccumulation of inorganic contaminants (e.g., cadmium, 
lead, mercury) from contaminated water bodies. Bats tend to accumulate 
inorganic contaminants due to their diet and slow means of elimination 
of these compounds (Plumb and Budde 2011, unpublished data). In 
Virginia, for example, the North Fork Holston River is a water body 
that was highly contaminated by a waterborne point source of mercury 
through contamination by a chlor-alkali plant. Based on findings from a 
pilot study for bats in 2005 (Yates and Evers 2006), there is 
sufficient information to conclude that bats from near-downstream areas 
of the North Fork Holston River have potentially harmful body burdens 
of mercury, although the effect on bats is unknown. Fur samples taken 
from eastern small-footed bats have also yielded detectable amounts of 
mercury and zinc (Hickey et al. 2001, p. 703). Hickey et al. (2001, p. 
705) suggest that the concentrations of mercury reported may be 
sufficient to cause sublethal biological effects to bats. Divoll et al. 
(in prep) found that eastern small-footed bats and northern long-eared 
bats showed consistently higher mercury levels than little brown bats 
or eastern red bats sampled in Maine, which may be correlated with 
gleaning behavior and the consumption of spiders by these two bat 
species. Eastern small-footed bats exhibited the highest mercury levels 
of all species. Bats recaptured during the study 1 or 2 years after 
their original capture maintained similar levels of mercury in fur 
year-to-year. Biologists suggest that individual bats accumulate body 
burdens of mercury that cannot be reduced once elevated to a certain 
threshold.
    Exposure to holding ponds containing flow-back and produced water 
associated with hydraulic fracturing operations may also expose bats to 
toxins, radioactive material, and other contaminants (Hein 2012, p. 8). 
Cadmium, mercury, and lead are contaminants reported in hydraulic 
fracturing operations. Whether bats drink directly from holding ponds 
or contaminants are introduced from these operations into aquatic 
ecosystems, bats will presumably accumulate these substances and 
potentially suffer adverse effects (Hein 2012, p. 9). In summary, the 
best available data indicate that contaminant exposure can pose an 
adverse effect to individual northern long-eared and eastern small-
footed bats, although it is not an immediate and significant risk in 
itself at a population level.
Prescribed Burning
    Eastern forest-dwelling bat species, such as the eastern small-
footed and northern long-eared bats, likely evolved with fire 
management of mixed-oak ecosystems (Perry 2012, p. 182). A recent 
review of prescribed fire and its effects on bats (U.S. Forest Service 
2012, p. 182) generally found that fire had beneficial effects on bat 
habitat. Fire may create snags for roosting and creates more open 
forests conducive to foraging on flying insects (Perry 2012, pp. 177-
179), although gleaners such as northern long-eared bats may readily 
use cluttered understories for foraging (Owen et al. 2003, p. 355). 
Cavity and bark roosting bats, such as the eastern small-footed and 
northern long-eared, use previously burned areas for both foraging and 
roosting (Johnson et al. 2009, p. 239; Johnson et al. 2010, p. 118). In 
Kentucky, the abundance of prey items for northern long-eared bats 
increased after burning (Lacki et al. 2009, p. 1170), and more roosts 
were found in post-burn areas (Lacki et al. 2009, p. 1169). Burning may 
create more suitable snags for roosting through exfoliation of bark 
(Johnson et al. 2009, p. 240), mimicking trees in the appropriate decay 
stage for roosting bats. In contrast, a prescribed burn in Kentucky 
caused a roost tree used by a radio-tagged female northern long-eared 
bat to prematurely fall after its base was weakened by smoldering 
combustion (Dickinson et al. 2009, p. 56). Low-intensity burns may not 
kill taller trees directly but may create snags of smaller trees and 
larger trees may be injured, resulting in vulnerability (of the tree) 
to pathogens that cause hollowing of the trunk, which provides roosting 
habitat (Perry 2012, p. 177). Prescribed burning also opens the tree 
canopy, providing more canopy light penetration (Boyles and Aubrey 
2006, p. 112; Johnson et al. 2009, p. 240), which may facilitate faster 
development of juvenile bats (Sedgeley 2001, p. 434). Although Johnson 
et al. (2009, p. 240) found the amount of roost switching did not 
differ between burned and unburned areas, the rate of switching in 
burned areas of every 1.35 days was greater than that found in other 
studies of every 2-3 days (Foster and Kurta 1999, p. 665; Owen et al. 
2002, p. 2; Carter and Feldhamer 2005, p. 261; Timpone et al. 2010, p. 
119).
    Direct effects of fire on bats likely differ among species and 
seasons (Perry 2012, p. 172). Northern long-eared bats have been seen 
flushing from tree roosts shortly after ignition of prescribed fire 
during the growing season (Dickinson et al. 2009, p. 60). Fires of 
reduced intensity that proceed slowly allow sufficient time for 
roosting bats to arouse from sleep or torpor and escape the fire 
(Dickinson et al. 2010, p. 2200), although extra arousals from fire 
smoke could cause increased energy loss (Dickinson et al. 2009, p. 52). 
During prescribed burns, bats are potentially exposed to heat and 
gases; the roosting behavior of these two species, however, may reduce 
their vulnerability to toxic gases. When trees are dormant, the bats 
are roosting in caves or mines (hibernacula can be protected from toxic 
gases through appropriate burn plans), and during the growing season, 
northern long-eared bats roost in tree cavities or under bark above the 
understory, above the area with the highest concentration of gases in a 
low-intensity prescribed burn (Dickinson et al. 2010, pp. 2196, 2200). 
Carbon monoxide levels did not reach critical thresholds that could 
harm bats in low-intensity burns at the typical roosting height for the 
eastern small-footed and northern long-eared bats (Dickinson et al. 
2010, p. 2196); thus heat effects from prescribed fire are of greater 
concern than gas effects on bats. Direct heat could cause injury to the 
thin tissue of bat ears and is more likely to occur than exposure to 
toxic gas levels during prescribed burns (Dickinson et al. 2010, p. 
2196). In addition, fires of reduced intensity with shorter flame 
height could lessen the effect of heat to bats roosting higher in trees 
(Dickinson et al. 2010, p. 2196).

[[Page 61072]]

Winter, early spring, and late fall generally contain less intense fire 
conditions than during other seasons and coincide with time periods 
when bats are less affected by prescribed fire due to low activity in 
forested areas. Furthermore, no young are present during these times, 
which reduces the likelihood of heat injury and exposure of vulnerable 
young to fire (Dickinson et al. 2010, p. 2200). Prescribed fire 
objectives, such as fires with high intensity and rapid ignition in 
order to meet vegetation goals, must be balanced with the exposure of 
bats to the effects of fire (Dickinson et al. 2010, p. 2201). 
Currently, the Service and U.S. Forest Service strongly recommend not 
burning in the central hardwoods from mid- to late April through summer 
to avoid periods when bats are active in forests (Dickinson et al. 
2010, p. 2200).
    Bats that occur in forests are likely equipped with evolutionary 
characteristics that allow them to exist in environments with 
prescribed fire. Periodic burning can benefit habitat through snag 
creation and forest canopy gap creation, but frequency and timing need 
to be considered to avoid direct and indirect adverse effects to bats 
when using prescribed burns as a management tool. We conclude that 
there may be adverse effects posed by prescribed burning to individual 
northern long-eared bats and eastern small-footed bats; however, there 
is no evidence suggesting effects from prescribed burning itself have 
led to population declines in either species.
Conservation Efforts To Reduce Other Natural or Manmade Factors 
Affecting Its Continued Existence
    In the Midwest, rapid wind development is a concern with regards to 
the effect to bats (Baker 2011, pers. comm.; Kath 2012, pers. comm.). 
Due to the known impact from wind energy development, in particular to 
listed (and species currently being evaluated to determine if listing 
is warranted) bird and bat species in the Midwest, the Service, State 
natural resource agencies, and wind energy industry representatives are 
developing the Midwest Wind Energy Multi-Species Habitat Conservation 
Plan (MSHCP). The planning area includes the Midwest Region of the 
Service, which includes all or portions of the following States: 
Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, and 
Wisconsin. The MSHCP would allow permit holders to proceed with wind 
energy development, which may result in ``incidental'' taking of a 
listed species under section 10 of the Act, through issuance of an 
incidental take permit (77 FR 52754; August 30, 2012). Currently, both 
the northern long-eared bat and eastern small-footed bat are being 
considered for inclusion as covered species under the MSHCP. The MSHCP 
will address protection of covered species through avoidance, 
minimization of take, and mitigation to offset effect of ``take'' 
(e.g., habitat preservation, habitat restoration, habitat enhancement) 
to help ameliorate the effect of wind development (77 FR 52754; August 
30, 2012). In some cases, the U.S. Forest Service has agreed to limit 
or restrict burning in the central hardwoods from mid- to late April 
through summer to avoid periods when bats are active in forests 
(Dickinson et al. 2010, p. 2200).
Summary of Factor E
    We have identified a number of factors (e.g., wind energy 
development, climate change, contaminants, prescribed burning) that may 
have direct or indirect effects on eastern small-footed bats and 
northern long-eared bats. Although such activities occur, there is no 
evidence that these activities alone have significant effects on either 
species, because their effects are often localized and not widespread 
throughout the species' ranges. However, these factors may have a 
cumulative effect on the northern long-eared bat when added to white-
nose syndrome, because the disease had led to dramatic population 
declines in that species (discussed under Factor C).
Cumulative Effects From Factors A Through E
    None of the factors discussed above under Factors A, B, C, or E, 
alone or in combination, is affecting the eastern small-footed bat at a 
population level. Conversely, WNS (Factor C) alone has led to dramatic 
and rapid population-level effects on the northern long-eared bat. 
White-nose syndrome is the most significant threat to the northern 
long-eared bat, and the species would likely not be imperiled were it 
not for this disease. However, although the effects on the northern 
long-eared bat from Factors A, B, and E individually or in combination 
do not have significant effects on the species, when combined with the 
significant population reductions due to white-nose syndrome (Factor 
C), the resulting cumulative effect may further adversely impact the 
species.

Finding

Eastern Small-Footed Bat

    As required by the Act, we considered the five factors in assessing 
whether the eastern small-footed bat is endangered or threatened 
throughout all of its range. We examined the best scientific and 
commercial information available regarding the past, present, and 
future threats faced by the eastern small-footed bat. We reviewed the 
petition, information available in our files, and other available 
published and unpublished information, and we consulted with recognized 
bat experts and other Federal and State agencies. Threats previously 
identified for the eastern small-footed bat include modification or 
destruction of winter and summer habitat, disturbance of hibernating 
bats from commercial and/or recreational activities in caves and mines, 
disease, wind energy development, climate change, and contaminants. The 
primary threat previously identified was WNS. While other species of 
hibernating bats have experienced mass mortality due to WNS, there is 
no indication of a population-level decline in eastern small-footed bat 
based on winter survey data. A review of pre-WNS and post-WNS 
hibernacula count data over multiple years finds that post-WNS counts 
were within the normal observed range at the majority of sites 
analyzed. Several life-history traits may reduce the susceptibility of 
this bat to WNS, which include their comparatively late arrival and 
early departure from hibernacula, departure from hibernacula during 
mild winter periods, solitary roosting habits, and selection of drier 
microhabitats (e.g., cave and mine entrances). We will continue to 
closely monitor the spread of WNS and its effects on eastern small-
footed bats. As for the other above-mentioned threats, although there 
is risk of exposure and individual mortality in isolated incidences, no 
declines in eastern small-footed bat populations have been documented.
    Our review of the best available scientific and commercial 
information indicates that the eastern small-footed bat is not in 
danger of extinction (endangered) nor likely to become endangered 
within the foreseeable future (threatened), throughout all of its 
range.
Distinct Vertebrate Population Segment
    After assessing whether the species is endangered or threatened 
throughout its range, we next consider whether a distinct vertebrate 
population segment (DPS) of the eastern small-footed bat meets the 
definition of an endangered or threatened species.
    Under the Service's Policy Regarding the Recognition of Distinct 
Vertebrate Population Segments Under the Endangered Species Act (61 FR 
4722;

[[Page 61073]]

February 7, 1996 (DPS Policy)), three elements are considered in the 
decision concerning the establishment and classification of a possible 
DPS. These are applied similarly for additions to or removal from the 
Federal List of Endangered and Threatened Wildlife. These elements 
include:
    (1) The discreteness of a population in relation to the remainder 
of the species to which it belongs;
    (2) The significance of the population segment to the species to 
which it belongs; and
    (3) The population segment's conservation status in relation to the 
Act's standards for listing, delisting, or reclassification (i.e., is 
the population segment endangered or threatened).

Discreteness

    Under the DPS policy, a population segment of a vertebrate taxon 
may be considered discrete if it satisfies either one of the following 
conditions:
    (1) It is markedly separated from other populations of the same 
taxon as a consequence of physical, physiological, ecological, or 
behavioral factors. Quantitative measures of genetic or morphological 
discontinuity may provide evidence of this separation; or
    (2) It is delimited by international governmental boundaries within 
which differences in control of exploitation, management of habitat, 
conservation status, or regulatory mechanisms exist that are 
significant in light of section 4(a)(1)(D) of the Act.
    There are no characteristics of the eastern small-footed bat's 
taxonomy, distribution or abundance, habitat, or biology (see the 
Species Information section, above) that suggest the species may be 
segmented into discrete populations. Throughout its range, the eastern 
small-footed bat has similar morphology and, as far as we know, 
genetics; uses similar roosting and foraging habitat; and exhibits 
similar roosting, foraging, and reproductive behavior. Therefore, the 
best available information indicates there is no evidence of markedly 
separated eastern small-footed bat populations.
    There are no characteristics of the eastern small-footed bat's 
management that suggest the species may be segmented into discrete 
populations. The eastern small-footed bat occurs in the Canadian 
provinces of Ontario and Quebec, as well as in the United States. 
However, the species is not listed under Canada's Species At Risk Act. 
In addition, we have no information to suggest that the species, its 
habitat, or the potential threats evaluated above in the five factor 
analysis are managed differently in the Canadian versus U.S. portions 
of the eastern small-footed bat's range. Therefore, the best available 
information indicates that there is no evidence that the eastern small-
footed bat is delimited by international governmental boundaries within 
which differences in control of exploitation, management of habitat, 
conservation status, or regulatory mechanisms exist that are 
significant in light of section 4(a)(1)(D) of the Act.
    We determine, based on a review of the best available information, 
that no population of the eastern small-footed bat meets the 
discreteness conditions of the 1996 DPS policy. Therefore, no eastern 
small-footed bat population qualifies as a DPS under our policy, and no 
population is a listable entity under the Act.
    The DPS policy is clear that significance is analyzed only when a 
population segment has been identified as discrete. Since we found that 
no population segment meets the discreteness element and, therefore, 
does not qualify as a DPS under the Service's DPS policy, we will not 
conduct an evaluation of significance.
Significant Portion of the Range
    Under the Act and our implementing regulations, a species may 
warrant listing if it is endangered or threatened throughout all or a 
significant portion of its range. The Act defines ``endangered 
species'' as any species which is ``in danger of extinction throughout 
all or a significant portion of its range,'' and ``threatened species'' 
as any species which is ``likely to become an endangered species within 
the foreseeable future throughout all or a significant portion of its 
range.'' The definition of ``species'' is also relevant to this 
discussion. The Act defines ``species'' as follows: ``The term 
`species' includes any subspecies of fish or wildlife or plants, and 
any distinct population segment [DPS] of any species of vertebrate fish 
or wildlife which interbreeds when mature.'' The phrase ``significant 
portion of its range'' (SPR) is not defined by the statute, and we have 
never addressed in our regulations: (1) The consequences of a 
determination that a species is either endangered or likely to become 
so throughout a significant portion of its range, but not throughout 
all of its range; or (2) what qualifies a portion of a range as 
``significant.''
    Two recent district court decisions have addressed whether the SPR 
language allows the Service to list or protect less than all members of 
a defined ``species'': Defenders of Wildlife v. Salazar, 729 F. Supp. 
2d 1207 (D. Mont. 2010), concerning the Service's delisting of the 
Northern Rocky Mountain gray wolf (74 FR 15123; April 2, 2009); and 
WildEarth Guardians v. Salazar, 2010 U.S. Dist. LEXIS 105253 (D. Ariz. 
September 30, 2010), concerning the Service's 2008 finding on a 
petition to list the Gunnison's prairie dog (73 FR 6660; February 5, 
2008). The Service had asserted in both of these determinations that it 
had authority, in effect, to protect only some members of a 
``species,'' as defined by the Act (i.e., species, subspecies, or DPS), 
under the Act. Both courts ruled that the determinations were arbitrary 
and capricious on the grounds that this approach violated the plain and 
unambiguous language of the Act. The courts concluded that reading the 
SPR language to allow protecting only a portion of a species' range is 
inconsistent with the Act's definition of ``species.'' The courts 
concluded that once a determination is made that a species (i.e., 
species, subspecies, or DPS) meets the definition of ``endangered 
species'' or ``threatened species,'' it must be placed on the list in 
its entirety and the Act's protections applied consistently to all 
members of that species (subject to modification of protections through 
special rules under sections 4(d) and 10(j) of the Act).
    Consistent with that interpretation, and for the purposes of this 
finding, we interpret the phrase ``significant portion of its range'' 
in the Act's definitions of ``endangered species'' and ``threatened 
species'' to provide an independent basis for listing; thus there are 
two situations (or factual bases) under which a species would qualify 
for listing: A species may be endangered or threatened throughout all 
of its range; or a species may be endangered or threatened in only a 
significant portion of its range. If a species is in danger of 
extinction throughout a significant portion of its range, the species 
is an ``endangered species.'' The same analysis applies to ``threatened 
species.'' Based on this interpretation and supported by existing case 
law, the consequence of finding that a species is endangered or 
threatened in only a significant portion of its range is that the 
entire species shall be listed as endangered or threatened, 
respectively, and the Act's protections shall be applied across the 
species' entire range.
    We conclude, for the purposes of this finding, that interpreting 
the significant portion of its range phrase as providing an independent 
basis for listing is the best interpretation of the Act because it is 
consistent with the purposes and the plain meaning of the key 
definitions of the Act; it does not conflict with established past 
agency practice (i.e.,

[[Page 61074]]

prior to the 2007 Solicitor's Opinion), as no consistent, long-term 
agency practice has been established; and it is consistent with the 
judicial opinions that have most closely examined this issue. Having 
concluded that the phrase ``significant portion of its range'' provides 
an independent basis for listing and protecting the entire species, we 
next turn to the meaning of ``significant'' to determine the threshold 
for when such an independent basis for listing exists.
    Although there are potentially many ways to determine whether a 
portion of a species' range is ``significant,'' we conclude, for the 
purposes of this finding, that the significance of the portion of the 
range should be determined based on its biological contribution to the 
conservation of the species. For this reason, we describe the threshold 
for ``significant'' in terms of an increase in the risk of extinction 
for the species. We conclude that a biologically based definition of 
``significant'' best conforms to the purposes of the Act, is consistent 
with judicial interpretations, and best ensures species' conservation. 
Thus, for the purposes of this finding, and as explained further below, 
a portion of the range of a species is ``significant'' if its 
contribution to the viability of the species is so important that 
without that portion, the species would be in danger of extinction.
    We evaluate biological significance based on the principles of 
conservation biology using the concepts of redundancy, resiliency, and 
representation. Resiliency describes the characteristics of a species 
and its habitat that allow it to recover from periodic disturbance. 
Redundancy (having multiple populations distributed across the 
landscape) may be needed to provide a margin of safety for the species 
to withstand catastrophic events. Representation (the range of 
variation found in a species) ensures that the species' adaptive 
capabilities are conserved. Redundancy, resiliency, and representation 
are not independent of each other, and some characteristic of a species 
or area may contribute to all three. For example, distribution across a 
wide variety of habitat types is an indicator of representation, but it 
may also indicate a broad geographic distribution contributing to 
redundancy (decreasing the chance that any one event affects the entire 
species), and the likelihood that some habitat types are less 
susceptible to certain threats, contributing to resiliency (the ability 
of the species to recover from disturbance). None of these concepts is 
intended to be mutually exclusive, and a portion of a species' range 
may be determined to be ``significant'' due to its contributions under 
any one or more of these concepts.
    For the purposes of this finding, we determine if a portion's 
biological contribution is so important that the portion qualifies as 
``significant'' by asking whether without that portion, the 
representation, redundancy, or resiliency of the species would be so 
impaired that the species would have an increased vulnerability to 
threats to the point that the overall species would be in danger of 
extinction (i.e., would be ``endangered''). Conversely, we would not 
consider the portion of the range at issue to be ``significant'' if 
there is sufficient resiliency, redundancy, and representation 
elsewhere in the species' range that the species would not be in danger 
of extinction throughout its range if the population in that portion of 
the range in question became extirpated (extinct locally).
    We recognize that this definition of ``significant'' (a portion of 
the range of a species is ``significant'' if its contribution to the 
viability of the species is so important that without that portion, the 
species would be in danger of extinction) establishes a threshold that 
is relatively high. On the one hand, given that the consequences of 
finding a species to be endangered or threatened in a significant 
portion of its range would be listing the species throughout its entire 
range, it is important to use a threshold for ``significant'' that is 
robust. It would not be meaningful or appropriate to establish a very 
low threshold whereby a portion of the range can be considered 
``significant'' even if only a negligible increase in extinction risk 
would result from its loss. Because nearly any portion of a species' 
range can be said to contribute some increment to a species' viability, 
use of such a low threshold would require us to impose restrictions and 
expend conservation resources disproportionately to conservation 
benefit: Listing would be rangewide, even if only a portion of the 
range of minor conservation importance to the species is imperiled. On 
the other hand, it would be inappropriate to establish a threshold for 
``significant'' that is too high. This would be the case if the 
standard were, for example, that a portion of the range can be 
considered ``significant'' only if threats in that portion result in 
the entire species' being currently endangered or threatened. Such a 
high bar would not give the significant portion of its range phrase 
independent meaning, as the Ninth Circuit held in Defenders of Wildlife 
v. Norton, 258 F.3d 1136 (9th Cir. 2001).
    The definition of ``significant'' used in this finding carefully 
balances these concerns. By setting a relatively high threshold, we 
minimize the degree to which restrictions will be imposed or resources 
expended that do not contribute substantially to species conservation. 
But we have not set the threshold so high that the phrase ``in a 
significant portion of its range'' loses independent meaning. 
Specifically, we have not set the threshold as high as it was under the 
interpretation presented by the Service in the Defenders litigation. 
Under that interpretation, the portion of the range would have to be so 
important that current imperilment there would mean that the species 
would be currently imperiled everywhere. Under the definition of 
``significant'' used in this finding, the portion of the range need not 
rise to such an exceptionally high level of biological significance. 
(We recognize that if the species is imperiled in a portion that rises 
to that level of biological significance, then we should conclude that 
the species is in fact imperiled throughout all of its range, and that 
we would not need to rely on the significant portion of its range 
language for such a listing.) Rather, under this interpretation we ask 
whether the species would be endangered everywhere without that 
portion, i.e., if that portion were completely extirpated. In other 
words, the portion of the range need not be so important that even the 
species being in danger of extinction in that portion would be 
sufficient to cause the species in the remainder of the range to be 
endangered; rather, the complete extirpation (in a hypothetical future) 
of the species in that portion would be required to cause the species 
in the remainder of the range to be endangered.
    The range of a species can theoretically be divided into portions 
in an infinite number of ways. However, there is no purpose to 
analyzing portions of the range that have no reasonable potential to be 
significant or to analyzing portions of the range in which there is no 
reasonable potential for the species to be endangered or threatened. To 
identify only those portions that warrant further consideration, we 
determine whether there is substantial information indicating that: (1) 
The portions may be ``significant,'' and (2) the species may be in 
danger of extinction there or likely to become so within the 
foreseeable future. Depending on the biology of the species, its range, 
and the threats it faces, it

[[Page 61075]]

might be more efficient for us to address the significance question 
first or the status question first. Thus, if we determine that a 
portion of the range is not ``significant,'' we do not need to 
determine whether the species is endangered or threatened there; if we 
determine that the species is not endangered or threatened in a portion 
of its range, we do not need to determine if that portion is 
``significant.'' In practice, a key part of the determination that a 
species is in danger of extinction in a significant portion of its 
range is whether the threats are geographically concentrated in some 
way. If the threats to the species are essentially uniform throughout 
its range, no portion is likely to warrant further consideration. 
Moreover, if any concentration of threats to the species occurs only in 
portions of the species' range that clearly would not meet the 
biologically based definition of ``significant,'' such portions will 
not warrant further consideration.
    We evaluated the current range of the eastern small-footed bat to 
determine if there is any apparent geographic concentration of 
potential threats for the species. We examined potential habitat 
threats from modification of cave and mine openings, mine reclamation, 
vandalism, wind energy development, and timber harvesting (Factor A); 
disturbance from cave recreation and research-related activities 
(Factor B); WNS and predation (Factor C); the inadequacy of existing 
regulatory mechanisms (Factor D); and collisions from wind energy 
development projects, climate change, contaminants, and prescribed 
burning (Factor E). We found no concentration of threats that suggests 
that the eastern small-footed bat may be in danger of extinction in a 
portion of its range. We found no portions of its range where potential 
threats are significantly concentrated or substantially greater than in 
other portions of its range. Therefore, we find that factors affecting 
the eastern small-footed bat are essentially uniform throughout its 
range, indicating no portion of the range warrants further 
consideration of possible endangered or threatened status under the 
Act. There is no available information indicating that there has been a 
range contraction for the species, and therefore we find that lost 
historical range does not constitute a significant portion of the range 
for the eastern small-footed bat. Our review of the best available 
scientific and commercial information indicates that the eastern small-
footed bat is not in danger of extinction (endangered) nor likely to 
become endangered within the foreseeable future (threatened), 
throughout all of its range or in a significant portion of its range. 
Therefore, we find that listing the eastern small-footed bat as an 
endangered or threatened species under the Act is not warranted at this 
time.
    We request that you submit any new information concerning the 
status of, or threats to, the eastern small-footed bat to our 
Pennsylvania Field Office, 315 South Allen Street, Suite 322, State 
College, PA 16801, whenever it becomes available. New information will 
help us monitor the eastern small-footed bat and encourage its 
conservation. If an emergency situation develops for the eastern small-
footed bat, we will act to provide immediate protection.

Northern Long-Eared Bat

    As required by the Act, we considered the five factors in assessing 
whether the northern long-eared bat is an endangered or threatened 
species, as cited in the petition, throughout all of its range. We 
examined the best scientific and commercial information available 
regarding the past, present, and future threats faced by the northern 
long-eared bat. We reviewed the petition, information available in our 
files, and other available published and unpublished information, and 
we consulted with recognized bat and disease experts and other Federal 
and State agencies.
    This status review identifies that the primary threat to the 
northern long-eared bat is attributable to WNS (Factor C), a disease 
caused by the fungus Geomyces destructans that is known to kill bats. 
The disease has led to dramatic and rapid population declines in 
northern long-eared bats of up to 99 percent from pre-WNS levels in 
some areas. White-nose syndrome has spread rapidly throughout the East 
and is currently spreading through the Midwest. We have no information 
to indicate that there are areas within the species' range that will 
not be impacted by the disease or that similar rates of decline (to 
what has been observed in the East, where the disease has been present 
for at most 8 years) will not occur throughout the species' range. 
Other sources of mortality to the species include wind-energy 
development, habitat modification, destruction and disturbance (e.g., 
vandalism to hibernacula, roost tree removal), effects of climate 
change, and contaminants. Although no significant decline due to these 
factors has been observed, they may have cumulative effects to the 
species in addition to WNS.
    On the basis of the best scientific and commercial information 
available, we find that the petitioned action to list the northern 
long-eared bat as an endangered or threatened species is warranted. A 
determination on the status of the species as an endangered or 
threatened species is presented below in the proposed listing 
determination.
Proposed Determination for Northern Long-Eared Bat
    Section 4 of the Act (16 U.S.C. 1533), and its implementing 
regulations at 50 CFR part 424, set forth the procedures for adding 
species to the Federal Lists of Endangered and Threatened Wildlife and 
Plants. Under section 4(a)(1) of the Act, we may list a species based 
on (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence. Listing actions may be warranted based on any of 
the above threat factors, singly or in combination.
    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
to the northern long-eared bat. There are several factors that affect 
the northern long-eared bat; however, we have found that no other 
threat is as severe and immediate to the species persistence as WNS 
(Factor C). Predominantly due to the emergence of WNS, the northern 
long-eared bat has experienced a severe and rapid decline in the 
Northeast, estimated at approximately 99 percent (from hibernacula 
data) since the disease was first discovered there in 2007. Summer 
survey data in the Northeast have confirmed rates of decline observed 
in northern long-eared bat hibernacula data post-WNS, with rates of 
decline ranging from 93 to 98 percent. This disease is considered the 
prevailing threat to the species, as there is currently no known cure. 
As mentioned under Factor C, although at the current time the disease 
has not spread throughout the species' entire range (WNS is currently 
found in 22 of 39 States where the northern long-eared bat occurs), it 
continues to spread, and we have no reason not to expect that where it 
spreads, it will have the same impact to the affected species (Coleman 
2013, pers. comm.). Although there is some uncertainty as far as when 
the disease will spread throughout the northern long-eared bat's range, 
all models that have attempted to project the spread of WNS (presented 
in Factor C) were in agreement that WNS will indeed spread

[[Page 61076]]

across the United States. In addition, human transmission could 
introduce the spread of the fungus to new locations that are far 
removed from the current known locations (Coleman 2013, pers. comm.). 
This threat is ongoing, is expected to increase in the future, and is 
significant because it continues to extirpate northern long-eared bat 
populations as it spreads and is expected to continue to spread 
throughout the species' range. Other threats to the northern long-eared 
bat include wind-energy development, winter and summer habitat 
modification, destruction and disturbance (e.g., vandalism to 
hibernacula, roost tree removal), climate change, and contaminants. 
Although these threats (prior to WNS) have not in and of themselves had 
significant impacts at the species level, they may increase the overall 
impacts to the species when considered cumulatively with WNS.
    The Act defines an endangered species as any species that is ``in 
danger of extinction throughout all or a significant portion of its 
range'' and a threatened species as any species ``that is likely to 
become endangered throughout all or a significant portion of its range 
within the foreseeable future.'' We find that the northern long-eared 
bat is presently in danger of extinction throughout its entire range 
based on the severity and immediacy of threats currently affecting the 
species. The overall range has been significantly impacted because a 
large portion of populations in the eastern part of the range have been 
extirpated due to WNS. White-nose syndrome is currently or is expected 
in the near future to impact the remaining populations. In addition 
other factors are acting in combination with WNS to reduce the overall 
viability of the species. The risk of extinction is high because the 
species is considered less common to rare in the areas not yet, but 
anticipated to soon be, affected by WNS, and significant rates of 
decline have been observed over the last 6 years in the core of the 
species' range, which is currently affected by WNS; these rates of 
decline are especially high in the eastern part of the species' range, 
where rates of decline have been as high as 99 percent in hibernating 
populations of the species. Therefore, on the basis of the best 
available scientific and commercial information, we propose listing the 
northern long-eared bat as endangered in accordance with sections 3(6) 
and 4(a)(1) of the Act. We find that a threatened species status is not 
appropriate for the northern long-eared bat because the threat of WNS 
has significant effects where it has occurred and is expected to spread 
rangewide in a short timeframe.
    Under the Act and our implementing regulations, a species may 
warrant listing if it is endangered or threatened throughout all or a 
significant portion of its range. The threats to the survival of the 
species occur throughout the species' range and are not restricted to 
any particular significant portion of that range. Accordingly, our 
assessment and proposed determination applies to the species throughout 
its entire range.
Available Conservation Measures
    Conservation measures provided to species listed as endangered or 
threatened under the Act include recognition, recovery actions, 
requirements for Federal protection, and prohibitions against certain 
practices. Recognition through listing results in public awareness, and 
conservation by Federal, State, Tribal, and local agencies; private 
organizations; and individuals. The Act encourages cooperation with the 
States and requires that recovery actions be carried out for all listed 
species. The protection required by Federal agencies and the 
prohibitions against certain activities are discussed, in part, below.
    The primary purpose of the Act is the conservation of endangered 
and threatened species and the ecosystems upon which they depend. The 
ultimate goal of such conservation efforts is the recovery of these 
listed species, so that they no longer need the protective measures of 
the Act. Subsection 4(f) of the Act requires the Service to develop and 
implement recovery plans for the conservation of endangered and 
threatened species. The recovery planning process involves the 
identification of actions that are necessary to halt or reverse the 
species' decline by addressing the threats to its survival and 
recovery. The goal of this process is to restore listed species to a 
point where they are secure, self-sustaining, and functioning 
components of their ecosystems.
    Recovery planning includes the development of a recovery outline 
shortly after a species is listed and preparation of a draft and final 
recovery plan. The recovery outline guides the immediate implementation 
of urgent recovery actions and describes the process to be used to 
develop a recovery plan. Revisions of the plan may be done to address 
continuing or new threats to the species, as new substantive 
information becomes available. The recovery plan identifies site-
specific management actions that set a trigger for review of the five 
factors that control whether a species remains endangered or may be 
downlisted or delisted, and methods for monitoring recovery progress. 
Recovery plans also establish a framework for agencies to coordinate 
their recovery efforts and provide estimates of the cost of 
implementing recovery tasks. Recovery teams (composed of species 
experts, Federal and State agencies, nongovernmental organizations, and 
stakeholders) are often established to develop recovery plans. When 
completed, the recovery outline, draft recovery plan, and the final 
recovery plan will be available on our Web site (https://www.fws.gov/endangered), or from our Green Bay, Wisconsin, Field Office (see FOR 
FURTHER INFORMATION CONTACT).
    Implementation of recovery actions generally requires the 
participation of a broad range of partners, including other Federal 
agencies, States, Tribal, nongovernmental organizations, businesses, 
and private landowners. Examples of recovery actions include habitat 
protection, habitat restoration (e.g., restoration of native 
vegetation) and management, research, captive propagation and 
reintroduction, and outreach and education. The recovery of many listed 
species cannot be accomplished solely on Federal lands because their 
range may occur primarily or solely on non-Federal lands. To achieve 
recovery of these species requires cooperative conservation efforts on 
private, State, and Tribal lands.
    If this species is listed, funding for recovery actions will be 
available from a variety of sources, including Federal budgets, State 
programs, and cost-share grants for non-Federal landowners, the 
academic community, and nongovernmental organizations. In addition, 
under section 6 of the Act, the State(s) of Alabama, Arkansas, 
Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Iowa, 
Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, 
Minnesota, Mississippi, Missouri, Montana, Nebraska, New Hampshire, New 
Jersey, New York, North Carolina, North Dakota, Ohio, Oklahoma, 
Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, 
Vermont, Virginia, West Virginia, Wisconsin, and Wyoming, and the 
District of Columbia, would be eligible for Federal funds to implement 
management actions that promote the protection or recovery of the 
northern long-eared bat. Information on our grant programs that are 
available to aid species recovery can be found at: https://www.fws.gov/grants.
    Although the northern long-eared bat is only proposed for listing 
under the Act at this time, please let us know if

[[Page 61077]]

you are interested in participating in recovery efforts for this 
species. Additionally, we invite you to submit any new information on 
this species whenever it becomes available and any information you may 
have for recovery planning purposes (see FOR FURTHER INFORMATION 
CONTACT).
    Section 7(a) of the Act requires Federal agencies to evaluate their 
actions with respect to any species that is proposed or listed as an 
endangered or threatened species and with respect to its critical 
habitat, if any is designated. Regulations implementing this 
interagency cooperation provision of the Act are codified at 50 CFR 
part 402. Section 7(a)(4) of the Act requires Federal agencies to 
confer with the Service on any action that is likely to jeopardize the 
continued existence of a species proposed for listing or result in 
destruction or adverse modification of proposed critical habitat. If a 
species is listed subsequently, section 7(a)(2) of the Act requires 
Federal agencies to ensure that activities they authorize, fund, or 
carry out are not likely to jeopardize the continued existence of the 
species or destroy or adversely modify its critical habitat. If a 
Federal action may affect a listed species or its critical habitat, the 
responsible Federal agency must enter into consultation with the 
Service.
    Federal agency actions within the species' habitat that may require 
conference or consultation or both as described in the preceding 
paragraph include management and any other landscape-altering 
activities on Federal lands administered by the U.S. Fish and Wildlife 
Service, U.S. Forest Service, NPS, and other Federal agencies; issuance 
of section 404 Clean Water Act (33 U.S.C. 1251 et seq.) permits by the 
U.S. Army Corps of Engineers; and construction and maintenance of roads 
or highways by the Federal Highway Administration.
    The Act and its implementing regulations set forth a series of 
general prohibitions and exceptions that apply to all endangered and 
threatened wildlife. The prohibitions of section 9(a)(2) of the Act, 
codified at 50 CFR 17.21 for endangered wildlife, in part, make it 
illegal for any person subject to the jurisdiction of the United States 
to take (includes harass, harm, pursue, hunt, shoot, wound, kill, trap, 
capture, or collect; or to attempt any of these), import, export, ship 
in interstate commerce in the course of commercial activity, or sell or 
offer for sale in interstate or foreign commerce any listed species. 
Under the Lacey Act (18 U.S.C. 42-43; 16 U.S.C. 3371-3378), it is also 
illegal to possess, sell, deliver, carry, transport, or ship any such 
wildlife that has been taken illegally. Certain exceptions apply to 
agents of the Service and State conservation agencies.
    We may issue permits to carry out otherwise prohibited activities 
involving endangered and threatened wildlife species under certain 
circumstances. Regulations governing permits are codified at 50 CFR 
17.22 for endangered species, and at Sec.  17.32 for threatened 
species. With regard to endangered wildlife, a permit must be issued 
for the following purposes: For scientific purposes, to enhance the 
propagation or survival of the species, and for incidental take in 
connection with otherwise lawful activities.
    It is our policy, as published in the Federal Register on July 1, 
1994 (59 FR 34272), to identify to the maximum extent practicable at 
the time a species is listed, those activities that would or would not 
constitute a violation of section 9 of the Act. The intent of this 
policy is to increase public awareness of the effect of a proposed 
listing on proposed and ongoing activities within the range of species 
proposed for listing. The following activities could potentially result 
in a violation of section 9 of the Act; this list is not comprehensive:
    (1) Unauthorized collecting, handling, possessing, selling, 
delivering, carrying, or transporting of the species, including import 
or export across State lines and international boundaries, except for 
properly documented antique specimens of these taxa at least 100 years 
old, as defined by section 10(h)(1) of the Act.
    (2) Incidental take of the species without authorization pursuant 
to section 7 or section 10(a)(1)(B) of the Act.
    (3) Disturbance or destruction of known hibernacula due to 
commercial or recreational activities during known periods of 
hibernation.
    (4) Unauthorized destruction or modification of summer habitat 
(including unauthorized grading, leveling, burning, herbicide spraying, 
or other destruction or modification of habitat) in ways that kills or 
injures individuals by significantly impairing the species' essential 
breeding, foraging, sheltering, or other essential life functions.
    (5) Unauthorized removal or destruction of trees and other natural 
and manmade structures being utilized as roosts by the northern long-
eared bat that results in take of the species.
    (6) Unauthorized release of biological control agents that attack 
any life stage of this taxon.
    (7) Unauthorized removal or exclusion from buildings or artificial 
structures being used as roost sites by the species, resulting in take 
of the species.
    (8) Unauthorized building and operation of wind energy facilities 
within areas used by the species, which results in take of the species.
    (9) Unauthorized discharge of chemicals, fill, or other materials 
into sinkholes which may lead to contamination of known northern long-
eared bat hibernacula.
    Questions regarding whether specific activities would constitute a 
violation of section 9 of the Act should be directed to the Green Bay, 
Wisconsin Ecological Services Field Office (see FOR FURTHER INFORMATION 
CONTACT).

Critical Habitat for Northern Long-Eared Bat

Background

    Critical habitat is defined in section 3 of the Act as:
    (1) The specific areas within the geographical area occupied by the 
species, at the time it is listed in accordance with the Act, on which 
are found those physical or biological features
    (a) Essential to the conservation of the species, and
    (b) Which may require special management considerations or 
protection; and
    (2) Specific areas outside the geographical area occupied by the 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    Conservation, as defined under section 3 of the Act, means to use 
and the use of all methods and procedures that are necessary to bring 
an endangered or threatened species to the point at which the measures 
provided pursuant to the Act are no longer necessary. Such methods and 
procedures include, but are not limited to, all activities associated 
with scientific resources management such as research, census, law 
enforcement, habitat acquisition and maintenance, propagation, live 
trapping, and transplantation, and, in the extraordinary case where 
population pressures within a given ecosystem cannot be otherwise 
relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the requirement that Federal agencies ensure, in consultation 
with the Service, that any action they authorize, fund, or carry out is 
not likely to result in the

[[Page 61078]]

destruction or adverse modification of critical habitat. The 
designation of critical habitat does not affect land ownership or 
establish a refuge, wilderness, reserve, preserve, or other 
conservation area. Such designation does not allow the government or 
public to access private lands. Such designation does not require 
implementation of restoration, recovery, or enhancement measures by 
non-Federal landowners. Where a landowner requests Federal agency 
funding or authorization for an action that may affect a listed species 
or critical habitat, the consultation requirements of section 7(a)(2) 
of the Act would apply, but even in the event of a destruction or 
adverse modification finding, the obligation of the Federal action 
agency and the landowner is not to restore or recover the species, but 
to implement reasonable and prudent alternatives to avoid destruction 
or adverse modification of critical habitat.
    Under the first prong of the Act's definition of critical habitat, 
areas within the geographical area occupied by the species at the time 
it was listed are included in a critical habitat designation if they 
contain physical or biological features (1) which are essential to the 
conservation of the species and (2) which may require special 
management considerations or protection. For these areas, critical 
habitat designations identify, to the extent known using the best 
scientific and commercial data available, those physical or biological 
features that are essential to the conservation of the species (such as 
space, food, cover, and protected habitat). In identifying those 
physical and biological features within an area, we focus on the 
principal biological or physical constituent elements (primary 
constituent elements such as roost sites, nesting grounds, seasonal 
wetlands, water quality, tide, soil type) that are essential to the 
conservation of the species. Primary constituent elements are those 
specific elements of the physical or biological features that provide 
for a species' life-history processes and are essential to the 
conservation of the species.
    Under the second prong of the Act's definition of critical habitat, 
we can designate critical habitat in areas outside the geographical 
area occupied by the species at the time it is listed, upon a 
determination that such areas are essential for the conservation of the 
species. For example, an area currently occupied by the species but 
that was not occupied at the time of listing may be essential to the 
conservation of the species and may be included in the critical habitat 
designation. We designate critical habitat in areas outside the 
geographical area occupied by a species only when a designation limited 
to its range would be inadequate to ensure the conservation of the 
species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific data available. Further, our Policy on 
Information Standards Under the Endangered Species Act (published in 
the Federal Register on July 1, 1994 (59 FR 34271)), the Information 
Quality Act (section 515 of the Treasury and General Government 
Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658)), 
and our associated Information Quality Guidelines, provide criteria, 
establish procedures, and provide guidance to ensure that our decisions 
are based on the best scientific data available. They require our 
biologists, to the extent consistent with the Act and with the use of 
the best scientific data available, to use primary and original sources 
of information as the basis for recommendations to designate critical 
habitat.
    When we are determining which areas should be designated as 
critical habitat, our primary source of information is generally the 
information developed during the listing process for the species. 
Additional information sources may include the recovery plan for the 
species, articles in peer-reviewed journals, conservation plans 
developed by States and counties, scientific status surveys and 
studies, biological assessments, other unpublished materials, or 
experts' opinions or personal knowledge.
    Habitat is dynamic, and species may move from one area to another 
over time. We recognize that critical habitat designated at a 
particular point in time may not include all of the habitat areas that 
we may later determine are necessary for the recovery of the species. 
For these reasons, a critical habitat designation does not signal that 
habitat outside the designated area is unimportant or may not be needed 
for recovery of the species. Areas that are important to the 
conservation of listed species, both inside and outside the critical 
habitat designation, continue to be subject to: (1) Conservation 
actions implemented under section 7(a)(1) of the Act, (2) regulatory 
protections afforded by the requirement in section 7(a)(2) of the Act 
for Federal agencies to ensure their actions are not likely to 
jeopardize the continued existence of any endangered or threatened 
species, and (3) section 9 of the Act's prohibitions on taking any 
individual of the species, including taking caused by actions that 
affect habitat. Federally funded or permitted projects affecting listed 
species outside their designated critical habitat areas may still 
result in jeopardy findings in some cases. These protections and 
conservation tools will continue to contribute to recovery of this 
species. Similarly, critical habitat designations made on the basis of 
the best available information at the time of designation will not 
control the direction and substance of future recovery plans, habitat 
conservation plans (HCPs), or other species conservation planning 
efforts if new information available at the time of these planning 
efforts calls for a different outcome.

Prudency Determination

    Section 4(a)(3) of the Act, as amended, and implementing 
regulations (50 CFR 424.12), require that, to the maximum extent 
prudent and determinable, the Secretary designate critical habitat at 
the time the species is determined to be endangered or threatened. Our 
regulations (50 CFR 424.12(a)(1)) state that the designation of 
critical habitat is not prudent when one or both of the following 
situations exist: (1) The species is threatened by taking or other 
human activity, and identification of critical habitat can be expected 
to increase the degree of threat to the species, or (2) such 
designation of critical habitat would not be beneficial to the species.
    There is currently no imminent threat of take attributed to 
collection or vandalism under Factor B for the northern long-eared bat, 
and identification and mapping of critical habitat is not expected to 
initiate any such threat. In the absence of finding that the 
designation of critical habitat would increase threats to a species, if 
there are any benefits to a critical habitat designation, then a 
prudent finding is warranted. The potential benefits of designation 
include: (1) Triggering consultation under section 7 of the Act, in new 
areas for actions in which there may be a Federal nexus where it would 
not otherwise occur because, for example, it is or has become 
unoccupied or the occupancy is in question; (2) focusing conservation 
activities on the most essential features and areas; (3) providing 
educational benefits to State or county governments or private 
entities; and (4) preventing people from causing inadvertent harm to 
the species. Therefore, because we have determined that the designation 
of critical habitat will not likely increase the degree of threat to 
the species and may provide some measure of benefit, we find that 
designation of critical

[[Page 61079]]

habitat is prudent for the northern long-eared bat.

Critical Habitat Determinability

    Having determined that designation is prudent, under section 
4(a)(3) of the Act we must find whether critical habitat for the 
species is determinable. Our regulations at 50 CFR 424.12(a)(2) state 
that critical habitat is not determinable when one or both of the 
following situations exist: (i) Information sufficient to perform 
required analyses of the impacts of the designation is lacking, or (ii) 
The biological needs of the species are not sufficiently well known to 
permit identification of an area as critical habitat.
    We reviewed the available information pertaining to the biological 
needs of the species and habitat characteristics where this species is 
located. Since information regarding the biological needs of the 
species is not sufficiently well known to permit identification of 
areas as critical habitat, we conclude that the designation of critical 
habitat is not determinable for the northern long-eared bat at this 
time.
    There are many uncertainties in designating hibernacula as critical 
habitat for the northern long-eared bat. First, we are not able to 
establish which of the large number of known hibernacula the species is 
known to inhabit are essential to the conservation of the species. This 
is due to the species typically being found in small numbers (often 
fewer than 10 individuals per hibernaculum). Also, those hibernacula 
with historically greater numbers (greater than 100) are often now 
infected with WNS, where the northern long-eared bat has been 
extirpated or close to extirpated. In addition, we lack sufficient 
information to define the physical and biological features or primary 
constituent elements with enough specificity; we are not able to 
determine how habitats affected by WNS (where populations previously 
thrived and are now extirpated) may contribute to the recovery of the 
species or whether those areas may still contain essential physical and 
biological features. Finally, for several States (e.g., Alabama, Iowa, 
Kansas, Montana, Nebraska, North Dakota, Oklahoma) within the species' 
range it is unknown if hibernacula occur within parts of the State, due 
to either the lack of survey effort or (especially the case in the 
western part of the range) the species being sparsely populated over a 
large landscape, making locating potential hibernacula challenging. 
Therefore, we currently lack the information necessary to propose 
critical habitat for the species.
    There are also uncertainties with potential designation of summer 
habitat, specifically maternity colony habitat. Although research has 
given us indication of some key summer roost requirements, the northern 
long-eared bat appears to be somewhat opportunistic in roost selection, 
selecting varying roost tree species and types of roosts throughout the 
range. Thus, it is not clear whether certain summer habitats are 
essential for the recovery of the species, or whether summer habitat is 
not a limiting factor for the species. Although research has shown some 
consistency in female summer roost habitat (e.g., selection of mix of 
live trees and snags as roosts, roosting in cavities, roosting beneath 
bark, and roosting in trees associated with closed canopy), the species 
and diameter of the tree (when tree roost is used) selected by northern 
long-eared bats for roosts vary widely depending on availability. 
Therefore, we are currently unable to determine whether specific summer 
habitat features are essential to the conservation of the species, and 
find that critical habitat is not determinable for the northern long-
eared bat at this time. We will seek more information regarding the 
specific winter and summer habitat features and requirements for the 
northern long-eared bat and make a determination on critical habitat no 
later than 1 year following any final listing.

Peer Review

    In accordance with our joint policy published in the Federal 
Register on July 1, 1994 (59 FR 34270), we will seek the expert 
opinions of at least three appropriate and independent specialists 
regarding this proposed rule. The purpose of peer review is to ensure 
that our listing determination for this species is based on 
scientifically sound data, assumptions, and analyses. We will invite 
these peer reviewers to comment during the public comment period.
    We will consider all comments and information we receive during the 
comment period on this proposed rule during preparation of a final 
rulemaking. Accordingly, the final decision may differ from this 
proposal.

Public Hearings

    The Act provides for one or more public hearings on this proposal, 
if requested. Requests must be received within 45 days after the date 
of publication of this proposal in the Federal Register. Such requests 
must be sent to the address shown in the FOR FURTHER INFORMATION 
CONTACT section. We will schedule public hearing on this proposal, if 
any are requested, and announce the dates, times, and places of those 
hearings, as well as how to obtain reasonable accommodations, in the 
Federal Register and local newspapers at least 15 days before the 
hearing.
    Persons needing reasonable accommodations to attend and participate 
in a public hearing should contact the Green Bay, Wisconsin, Field 
Office at 920-866-1717, as soon as possible. To allow sufficient time 
to process requests, please call no later than 1week before the hearing 
date. Information regarding this proposed rule is available in 
alternative formats upon request.

Required Determinations

Clarity of the Rule

    We are required by Executive Orders 12866 and 12988 and by the 
Presidential Memorandum of June 1, 1998, to write all rules in plain 
language. This means that each rule we publish must:
    (1) Be logically organized;
    (2) Use the active voice to address readers directly;
    (3) Use clear language rather than jargon;
    (4) Be divided into short sections and sentences; and
    (5) Use lists and tables wherever possible.
    If you feel that we have not met these requirements, send us 
comments by one of the methods listed in the ADDRESSES section. To 
better help us revise the rule, your comments should be as specific as 
possible. For example, you should tell us the numbers of the sections 
or paragraphs that are unclearly written, which sections or sentences 
are too long, the sections where you feel lists or tables would be 
useful, etc.

National Environmental Policy Act (42 U.S.C. 4321 et seq.)

    We have determined that environmental assessments and environmental 
impact statements, as defined under the authority of the National 
Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), need not be 
prepared in connection with listing a species as an endangered or 
threatened species under the Endangered Species Act. We published a 
notice outlining our reasons for this determination in the Federal 
Register on October 25, 1983 (48 FR 49244).

References Cited

    A complete list of references cited in this rulemaking is available 
on the Internet at https://www.regulations.gov and upon request from the 
Green Bay, Wisconsin, Field Office (see FOR FURTHER INFORMATION 
CONTACT).

[[Page 61080]]

Authors

    The primary authors of this proposed rule are the staff members of 
the Green Bay, Wisconsin, Field Office and the State College, 
Pennsylvania, Ecological Services Field Office.

List of Subjects in 50 CFR Part 17

    Endangered and threatened species, Exports, Imports, Reporting and 
recordkeeping requirements, Transportation.

Proposed Regulation Promulgation

    Accordingly, we propose to amend part 17, subchapter B of chapter 
I, title 50 of the Code of Federal Regulations, as set forth below:

PART 17--[AMENDED]

0
1. The authority citation for part 17 continues to read as follows:

    Authority: 16 U.S.C. 1361-1407; 1531-1544; 4201-4245, unless 
otherwise noted.

0
2. Amend Sec.  17.11(h) by adding an entry for ``Bat, northern long-
eared'' in alphabetical order under MAMMALS to the List of Endangered 
and Threatened Wildlife to read as follows:


Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------
                   Species                                         Vertebrate
----------------------------------------------                  population where
                                                Historic range    endangered or        Status          When listed    Critical habitat    Special rules
         Common name          Scientific name                      threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
           Mammals
 
                                                                      * * * * * * *
Bat, northern long-eared....  Myotis           U.S.A. (AL, AR,  Entire..........  E...............                    NA..............  NA
                               septentrionali   CT, DE, DC,
                               s.               FL, GA, IL,
                                                IN, IA, KS,
                                                KY, LA, ME,
                                                MD, MA, MI,
                                                MN, MS, MO,
                                                MT, NE, NH,
                                                NJ, NY, NC,
                                                ND, OH, OK,
                                                PA, RI, SC,
                                                SD, TN, VT,
                                                VA, WV, WI,
                                                WY); Canada
                                                (AB, BC, LB,
                                                MB, NB, NF,
                                                NS, NT, ON,
                                                PE, QC, SK,
                                                YT).
 
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------


    Dated: September 10, 2013.
 Stephen Guertin,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2013-23753 Filed 10-1-13; 8:45 am]
BILLING CODE 4310-55-P