November 28, 2007

Mr. Jose Sepulveda

Division Administrator

Federal Highway Administration

330 West Broadway

Frankfort, Kentucky 40601

Subject: FWS #07-B-1102; Final Biological Opinion on the Reconstruction
of US 119 from Partridge to Oven Fork in Letcher County, Kentucky and
its effects on the Indiana bat;

KYTC Item Numbers: 12-311.34, 12-311.35, 12-311.36, 12-311.73, and
12-311.77

Dear Mr. Sepulveda:

This document sends the U.S. Fish and Wildlife Service's (Service)
biological opinion based on our review of the Federal Highway
Administration's (FHWA) proposed reconstruction of US 119 from Partridge
to Oven Fork in Letcher County, Kentucky, and its effects on the Indiana
bat (*Myotis sodalis*) under section 7 of the Endangered Species Act
(Act) of 1973, as amended (16 U.S.C. 1531 *et seq*.). Your July 16, 2007
request for formal consultation was received on July 16, 2007.

This biological opinion is based on information provided in the FHWA's
July 10, 2007 biological assessment (BA), meetings (see consultation
history), other available literature, personal communications with
experts on the federally listed species considered in this biological
opinion, and other sources of information available to us and/or in our
files. A complete administrative record of this consultation is on file
at the Service's Kentucky Field Office in Frankfort, Kentucky.

The Service has reviewed the BA for the proposed reconstruction of US
119 and all of the above-referenced supporting information. The BA
evaluated the potential and likely effects of the proposed highway
construction project on three federally listed species. We concurred
with the FHWA's effects determination of "not likely to adversely
affect" for two of the three federally listed species (*Myotis
grisescens* and *Phoxinus cumberlandensis*) addressed by the BA. Our
concurrence was provided in a separate letter dated November 26, 2007 to
the FHWA. This document, therefore, represents our biological opinion on
the effects of the subject action on the endangered Indiana bat pursuant
to section 7 of the Act. The Indiana bat was the only species for which
the FHWA made a "may affect -- likely to adversely affect" determination
in the BA relative to the reconstruction of US 119.

**Consultation History**

June 1, 2005, the Service provides the Kentucky Transportation Cabinet
(KYTC) with a county species list of federally listed species that may
occur within the county and/or the proposed project area.

Between July 2005 and May 2007, several informal conversations occurred
between the Service and KYTC, to discuss the development of the BA, gray
bat avoidance and minimization measures, and the potential need for
formal consultation on the Indiana bat.

March 8, 2007, the Service receives a draft BA from KYTC dated February
2, 2007, for review and comment.

May 22, 2007, a meeting was held between the Service and KYTC to discuss
the draft BA. The Service provided verbal comments regarding the draft
BA's project description and effects analysis on the Indiana bat.

June 14, 2007, the Service received draft conservation measures from
KYTC via e-mail and provided verbal comments.

July 16, 2007, the Service receives a request from the FHWA, dated July
16, 2007, to initiate formal consultation on the proposed project. The
FHWA's request includes the final BA dated July 10, 2007.

August 16, 2007, the Service sent a letter to the FHWA acknowledging
that the FHWA's July 16, 2007, request for initiation of formal
consultation was received, that the information contained in the final
BA was complete, and that formal consultation had been initiated.

October 15, 2007, a meeting was held between the Service, FHWA, and KYTC
to discuss the proposed minimization measures within the BA. The Service
provided verbal comments recommending more suitable measures to minimize
the projects effect on the Indiana bat. Both the FHWA and KYTC agreed to
the recommended measures.

November 26, 2007, the Service sent a Draft Biological Opinion (BO) to
the FHWA and KYTC for review via electronic mail.

November 27, 2007, The Service received comments regarding the draft BO
from the FHWA, and KYTC.

November 28, 2007, the Service provided the FHWA with the Final
Biological Opinion on the proposed project.

**BIOLOGICAL OPINION**

#### **DESCRIPTION OF THE PROPOSED ACTION**

As defined in the Service's section 7 regulations (50 CFR 402.02),
"action" means "all activities or programs of any kind authorized,
funded, or carried out, in whole or in part, by Federal agencies in the
United States or upon the high seas." The "action area" is defined as
"all areas to be affected directly or indirectly by the Federal action
and not merely the immediate area involved in the action." The direct
and indirect effects of the actions and activities must be considered in
conjunction with the effects of other past and present Federal, State,
or private activities, as well as the cumulative effects of reasonably
certain future State or private activities within the action area.

The proposed action is the reconstruction of a section of US 119 located
near Pine Mountain. The proposed reconstruction would run from Partridge
to Oven Fork beginning at Andy Branch, 0.2 miles (mi) east of Partridge
and extending to 0.4 mi west of the US 119 intersection with KY 806, a
distance of approximately 7 mi. The purpose of the project is to improve
safety conditions and service on a route that accommodates both local
and regional traffic, as well as coal and timber trucks. This
construction section would link to an updated section of US 119 near
Cumberland and would eventually connect to the proposed US 119 tunnel
through Pine Mountain.

The reconstructed roadway would have two 12-foot (ft) driving lanes with
12-ft shoulders that would be increased by another 2 feet where a
guardrail is necessary. The design speed is 60 miles-per-hour with
partial access control. The proposed project requires four areas to
manage excess waste (i.e., earth and rock) removed during construction
of the roadway. Each of the waste areas is located to the southeast of
existing US 119. Waste area 1 will be located between Colliers Creek and
Maggard Branch; waste area 2 will be located in the upstream reaches of
Roberts Branch; waste area 3 will be located within the Joe Day Branch
watershed; and waste area 4 will be located along Brown Branch. The KYTC
estimates that the project, including waste areas, would encompass 623
total acres described as residential, agricultural land, coal mine land,
railroad right-of-way, and forestland. Of this acreage, a total of 456
acres of forestland (also described as potential summer roosting habitat
for the Indiana bat in the assessment) will be cleared. Specifically,
the removal of forested areas includes 319 acres of the 413 total acres
within the alignment's right-of-way, 24 of the 26 total acres in waste
area 1, 47 of the 63 total acres in waste area 2, 26 of the 55 total
acres in waste area 3, and 40 of the 66 total acres in waste area 4.

This biological opinion addresses only those actions for which the
Service believes adverse effects may occur. In the BA, the FHWA outlined
those activities in the proposed reconstruction of US 119 that are
expected to result in adverse effects on the Indiana bat. This
biological opinion addresses whether the reconstruction of the US 119
alternative is likely to jeopardize the continued existence of the
Indiana bat.

**Project Description**

The proposed project is the construction of the selected alternate that
begins at Andy Branch at Station (STA) 42+900 and travels through a
residential area along existing US 119 until it crosses Poor Fork at STA
43+580. The alignment crosses the Poor Fork floodplain, including a 1.2
acre forested wetland dominated by river birch at STA 43+820. Within the
floodplain, a bridge from STA 44+137 to STA 44+716 would span Poor Fork
three times, including the residential area along Colliers Creek. From
STA 44+716 to STA 45+800, there would be a series of cuts into forested
hillsides that will be up to 180 ft deep. At STA 45+800, the road
crosses the faceup (i.e., the outside entrance and staging area) of an
active underground mine along with a detention pond. From STA 45+800 to
STA 47+450, there is another series of cuts into forested hillsides up
to 180 ft deep. At STA 46+800 and STA 47+125, the roadway crosses major
mine access roads, and, at STA 47+122, a tie to existing US 119 would
require the construction of a bridge over Poor Fork. A utility easement
is crossed at STA 47+450. The alignment travels through a 3.9-acre
series of emergent and scrub-shrub wetlands from STA 47+450 to 47+850.
From STA 47+850 to STA 48+900 near Joe Day Branch, the roadway would cut
into forested hillsides up to 192 ft deep and cross recently reclaimed
surface mine and two sediment ponds. At STA 48+900, the alignment
crosses Joe Day Branch and logging roads. A series of cuts into forested
hillsides up to 174 ft deep extends from STA 48+900 to STA 50+000. This
roadway section also includes one sediment pond and a gas pipeline
crossing. An old slurry disposal area occurs from STA 50+000 to STA
50+360 and includes a Poor Fork and railroad bridge crossing at STA
50+075 and a Poor Fork crossing at STA 50+340. STA 50+360 to STA 51+040
would predominately consist of fill material up to 33 feet high. This
section currently includes a serpentine-shaped sediment
pond/water-treatment area, three other sediment ponds, and an open
reclaimed area on Cumberland River Coal property. At STA 50+600, there
will be a proposed approach tie to existing US 119 that incorporates a
Poor Fork crossing. The roadway crosses Brown Branch at STA 51+050. From
STA 51+050 to 51+800, there is a commercial property at 51+100, followed
by a 148-feet deep cut into forested hillsides. The alignment then
crosses Poor Fork at STA 51+515, travels through a residential area, and
crosses Poor Fork again at STA 51+705. From STA 51+750 to STA 26+100,
the alignment cuts into forested hillsides up to 207 ft deep and then
crosses Poor Fork at STA 25+930 before ending at existing US 119.

#### **Action Area**

The "action area" is defined by regulation as all areas to be affected
directly or indirectly by the Federal action and not merely the
immediate area involved in the action \[50 CFR §402.02\]. The action
area is not limited to the "footprint" of the action, nor is it limited
by authority of the federal agency. The US 119 project is a long, linear
project that cuts across mostly forested land in addition to waterways,
agricultural land, residential areas, and mine land. Indiana bats are
known to occur within and adjacent to the project's boundaries located
in Pine Mountain. Surveys conducted for the proposed project resulted in
the capture of a juvenile male Indiana bat prior to the time when
juvenile male bats are thought to migrate away from the maternity
colony. Therefore, the assessment, and subsequently the Service, based
the assumption of a maternity colony being present in the region and/or
project area. In total, there are approximately 20 Indiana bat capture
records and three known Indiana bat hibernacula (Crystal Cave, Line Fork
Cave, and Green Cave) within Pine Mountain and adjacent to the project
area. Two of these hibernacula (Crystal Cave and Line Fork Cave) are
within 5 miles of the proposed project and Green Cave is approximately
10 miles from the proposed project. Survey efforts in the area of Pine
Mountain, not associated with the proposed action, captured an
individual male Indiana bat in the summer of 2006 from underneath a
bridge on US 119 just a few miles southwest of the project area. This
bat was banded the night of capture and, in February 2007, the banded
bat was recovered in Green Cave. This suggests that some Indiana bats
utilize both summer roosting habitat and the hibernacula within the Pine
Mountain area.

Much of the roadway alignment and associated waste areas contains
forested land that is potentially suitable as Indiana bat maternity
foraging and roosting habitat. The disturbances occurring within the
action area may overlap maternity colony foraging and roosting habitat
that is centered up to 2.5 miles away on either side of the proposed
roadway and extending from each terminus. In addition, the proposed
project is within and/or near the 10-mile radius around three known
hibernacula. As a consequence, potential Indiana bat maternity, summer
roosting, spring staging and migration, fall swarming, and fall foraging
and roosting habitat could be affected through direct loss, alteration,
fragmentation, or displacement induced by the new roadway, and
subsequent traffic use.

In order to ensure the consideration of all potential direct, indirect,
and cumulative effects of the proposed action on the Indiana bat, the
action area under consideration in this Biological Opinion will include
those areas within the right-of-way disturbance limits for the entire
project length, the described waste areas associated with the project,
and an area approximately 10 miles on either side of the pinnacle of
Pine Mountain within Letcher and Harlan Counties, Kentucky (see project
location and action area map, Appendix A). The Service has described the
action area in this way for the reasons identified above and explained
and discussed later in the "EFFECTS OF THE ACTION" section of this
consultation.

**Description of the Action Area**

The proposed section of US 119 is situated in the mountainous region of
southeastern Kentucky in Letcher County and directly adjacent to Harlan
County. Letcher and Harlan Counties are located within the Eastern
Kentucky Coal Field with topography consisting of mountains and valleys.
Pine Mountain, where the project is located, and Black Mountain are the
most conspicuous topographic features in the area. Elevations along the
crest of Pine Mountain range from 2,600 to 2,900 feet, with the highest
peak at an elevation of 3,273 feet. Topography of the action area ranges
from floodplain to mountainous which give rise to numerous miles of
ephemeral to perennial streams within the action area. Named streams
located within the project corridor include Poor Fork of the Cumberland
River, Colliers Creek, Maggard Branch, Roberts Branch, Joe Day Branch,
and Brown Branch.

Second and third growth forest composed of mixed mesophytic forest
communities dominate the region. Mesic sites are dominated by beech,
yellow-poplar, sugar maple, and white oak with associates consisting of
ash, black walnut, buckeye, basswood, and northern red oak. White oak
and hickory dominate drier slopes. Pines grow in sandy soils on steep
sandstone slopes. Coves are composed of hemlock and magnolia with a
rhododendron understory. Reclaimed mine lands are planted in tall
fescue, black locust, and exotic shrubs. Land uses within the area
include timber harvesting, underground and surface coal mining, gas
production, residential development, and agricultural crop and
pastureland.

The project area is predominantly underlain by the Hance Formation of
Pennsylvanian age, which consists of siltstone, sandstone, shale, and
coal. Thickness of the Hance Formation is approximately 1,500 feet.
Significant coal mining, both surface and underground, has and continues
to occur on Black Mountain, and within the action area. Active
underground mines are located within the project corridor, and there are
six underground mines designated as closed, which are located to the
south of the project alignment.

#### **STATUS OF THE SPECIES/CRITICAL HABITAT**

### 

**Species/critical habitat description**

**Listing status**

The Indiana bat (*Myotis sodalis*) is a temperate, insectivorous,
migratory bat that hibernates in mines and caves in the winter and
summers in wooded areas. The species was originally listed as being in
danger of extinction under the Endangered Species Preservation Act of
1966 (32 FR 4001, March 11, 1967), and is currently listed as endangered
under the Act of 1973, as amended. Critical habitat for the Indiana bat
was designated on September 24, 1976; it consisted of 11 caves and two
mines in six states (September 24, 1976). The original recovery plan for
the species was published in 1983 (Service 1983). An agency draft of a
revised plan was published in 1999 but was never finalized. The Recovery
Priority of the Indiana Bat is 8, which means that the species has a
moderate degree of threat and high recovery potential.

### Critical Habitat 

Critical habitat was designated for the species on 24 September 1976
(Service 1976). Eleven caves and two mines in six states were listed as
critical habitat:

> Illinois - Blackball Mine (LaSalle Co.);
>
> Indiana - Big Wyandotte Cave (Crawford Co.), Ray's Cave (Greene Co.);
>
> Kentucky - Bat Cave (Carter Co.), Coach Cave (Edmonson Co.);
>
> Missouri - Cave 021 (Crawford Co.), Caves 009 and 017 (Franklin Co.),
> Pilot Knob Mine
>
> (Iron Co.), Bat Cave (Shannon Co.), Cave 029 (Washington Co.);
>
> Tennessee - White Oak Blowhole Cave (Blount Co.); and

West Virginia - Hellhole Cave (Pendleton Co.).

Under section 7(a)(2) of the Act, Federal agencies must take such action
as necessary to insure that actions authorized, funded, or carried out
by them do not result in the destruction or modification of these
critical habitat areas.

**Species Description**

The Indiana bat is a medium-sized bat in the genus *Myotis*. Its forearm
length is 1^3^/8­-1^5^/8 in), and the head and body length ranges from
15/8­-17/8 in. This species closely resembles the little brown bat (*M.
lucifugus*) and the northern long-eared bat (*M. septentrionalis*)
(Barbour and Davis 1969). The northern long-eared bat is separated
easily from the other two species by its long, pointed, symmetrical
tragus (see figs. 15 and 34 in Barbour and Davis 1969). The Indiana bat
usually has a distinctly keeled calcar (spur-like projection on wing),
whereas the little brown bat does not (see Figure 42 in Barbour and
Davis 1969). The hind feet of an Indiana bat tend to be small and
delicate, with fewer, shorter hairs (i.e., the hairs do not extend
beyond the claws) than its congeners (see Figure 14 in Barbour and Davis
1969). The ears and wing membranes have a dull appearance and flat
coloration that does not contrast with the fur, and the fur lacks luster
compared with that of little brown bats (Barbour and Davis 1969, Hall
1981). The nose of an Indiana bat is lighter in color than that of a
little brown bat. The skull of an Indiana bat has a small sagittal crest
(boney ridge on top of skull), and the braincase tends to be smaller,
lower, and narrower than that of the little brown bat (Barbour and Davis
1969, Hall 1981).

**Taxonomy**

The Indiana bat was first described as a species by Miller and Allen
(1928), based on museum specimens collected in 1904 from Wyandotte Cave
in Crawford County, Indiana. Before that time, specimens of the Indiana
bat often were confused with those of other *Myotis*, especially the
little brown bat. "That *Myotis sodalis* has been so long overlooked is
due no doubt to the general resemblance the animal bears to *Myotis
lucifugus*, with which species the specimens of it in museums have
generally been confused; when its characteristics are recognized,
however, there is no doubt as to its identity" (Miller and Allen 1928).
The Indiana bat is monotypic, indicating there are no recognized
subspecies. Alternative common names for the species are Indiana myotis,
social bat, pink bat, and little sooty bat (Bailey 1933, Osgood 1938,
Nason 1948, Mumford and Whitaker 1982).

**Population Distribution and Abundance**

[Prehistoric Distribution and Abundance]{.underline}

Our understanding of the Indiana bat's prehistoric distribution and
abundance is primarily limited to extrapolations from early historical
accounts and the study of paleontological remains in caverns in the
eastern United States because there does not appear to be a fossil
record for *Myotis sodalis* (Thomson 1982). Researchers have identified
several important prehistoric (and historic) Indiana bat hibernacula by
analyzing bat bones, mummified bodies, guano deposits, stains and claw
marks on cave ceilings and walls, and raccoon (*Procyon lotor*) scat
containing *Myotis* bones and hair. For example, Tuttle (1997), using
historical accounts and an analysis of staining (i.e., discolored areas
of the wall or ceiling due to consistent and prolonged roosting by
bats), concluded that Mammoth Cave, Kentucky, once housed one of the
largest hibernating colonies of bats yet identified, with an estimated
9-13 million bats (primarily *M. sodalis* and *M. grisescens*). Even
though Toomey et al. (2002) readily acknowledged difficulties in
analyzing and limitations in interpreting cave roost stains, when taken
together their historic and paleontological analysis in Mammoth Cave's
Historic Entrance area supported the idea that Mammoth Cave once held a
large number of Indiana bats.

Similarly, Munson and Keith's (1984) previous historic research and
paleontological analysis of prehistoric raccoon scat in Wyandotte Cave,
Indiana, suggested that a large hibernating population of *Myotis*
roosted near the entrance of this extensive cave system throughout the
last 1,500 years. Assuming their results were from a representative
sample of the raccoon activity areas in Wyandotte Cave, they
conservatively estimated that the cave contained 676,900 fecal segments,
which collectively would contain remains of an estimated 1,713,000
individual bats (presumably *M. sodalis* was the predominant species
present and preyed upon).

Other paleontological evidence indicating that prehistoric (or historic)
Indiana bat numbers were once much higher has been documented in Bat
Cave, Kentucky, where an analysis of bone deposits revealed an estimated
300,000 Indiana bats had died during a single flood event at some
previous point in time (Hall 1962). It is uncertain whether this
catastrophic population loss occurred during prehistoric times or
perhaps as recently as "The Great Flood of 1937," which devastated much
of the Ohio River valley (Hall 1962).

As a whole, existing paleontological evidence suggests that prehistoric
abundance of Indiana bats may have exceeded most historic accounts and
our current total population estimate by an order of magnitude. However,
our degree of confidence in the accuracy of most prehistoric and
historic population estimates remains relatively low because these
estimates often depend on assumptions that cannot be readily tested, and
confounding issues are common. For example, even conservative population
estimates of Indiana bats based on stained areas on cave ceilings should
be viewed with caution. Unfortunately, researchers currently have no
means of empirically determining what percentage of the stained roosting
areas found in caves today are attributable to the different *Myotis*
species or over what period of time the stains were actually deposited
(e.g., decades, centuries). Logically, in prehistoric or pre-settlement
times, other *Myotis* species, such as the little brown bat and gray
bat, may have been more abundant as well. However, because they
typically do not aggregate on cave ceilings as tightly packed as do
Indiana bats, population estimates made from their stains may not only
be falsely attributed to *M. sodalis*, but would be overestimated as
well.

[Historic Winter Distribution]{.underline}

Historically, the Indiana bat had a winter range restricted to areas of
cavernous limestone in the karst regions of the east-central United
States (Miller and Allen 1928, Hall 1962, Thomson 1982, Figure 1). Prior
to and during much of the European settlement of the eastern United
States, winter populations of Indiana bats likely occurred in karst
regions of what would eventually become Alabama, Arkansas, Georgia,
Illinois, Indiana, Iowa, Kentucky, Maryland, Massachusetts, Missouri,
New Jersey, New York, North Carolina, Oklahoma, Pennsylvania, Tennessee,
Vermont, Virginia, and West Virginia. Based on early accounts and other
indirect evidence (Silliman et al. 1851, Blatchley 1897, Tuttle 1997,
Tuttle 1999), some researchers have suggested that vast numbers,
presumably the majority, of Indiana bats historically converged at a
relatively small number of large complex cave systems to hibernate
(e.g., Wyandotte Cave in Indiana; Bat, Coach, and Mammoth caves in
Kentucky; Great Scott Cave in Missouri; and Rocky Hollow Cave in
Virginia) and used other caves to a lesser extent (Olson 1996, Tuttle
1997, Tuttle 1999, Toomey et al. 2002, Whitaker et al. 2003).

When Miller and Allen first described *Myotis sodalis* in 1928, they had
examined museum specimens originating from ten states including Alabama,
Arkansas, Illinois, Indiana, Kentucky, Michigan, North Carolina,
Pennsylvania, Tennessee, and Vermont (Miller and Allen 1928). Based on
these records, they described the species' distribution as the "eastern
United States from the central Mississippi Valley and northern Alabama
to the western part of New England" (Figure 2). Because the majority of
the specimens they had studied were collected from wintering localities,
Miller and Allen (1928) noted that the species' summer distribution
likely covered a more considerable area, which decades later proved to
be true. By 1960, winter populations of Indiana bats had been reported
from about 74 different hibernacula in 18 states (Service, unpublished
data, 2006).

![](media/image1.png){width="2.1381944444444443in"
height="2.2666666666666666in"}

![](media/image2.wmf){width="1.9645833333333333in"
height="2.2444444444444445in"}

**Figure 1.** Cavern areas of the eastern United States (from Davies
1970) (on left).

**Figure 2.** Known distribution of *Myotis sodalis* in 1928 (from
Miller and Allen 1928) (on right).

[Historic Summer Distribution]{.underline}

The historic summer distribution and range for this species is poorly
documented. The first maternity colony was not discovered until the
summer of 1971 in east-central Indiana (Cope et al. 1974). Nonetheless,
based on our knowledge of Indiana bat seasonal migration patterns and
limits, and locations of historic and potential hibernacula, it is
reasonable to assume that the species' historic summer distribution was
more or less similar to its summer distribution (Figure 3).

The historic summer range included areas where the bats have now been
locally extirpated due to extensive loss and fragmentation of summer
habitat (e.g., forests, woodlands, wetlands). This loss of habitat
resulted from land-use changes that began with pioneer settlements, and
continue to the present in some areas from ongoing development,
agriculture, and coal and mineral extraction. Habitat within the
historic summer range sustained millions of Indiana bats during the
pre-settlement and early settlement period, which may no longer be
feasible today. Gardner and Cook (2002) provided a historical summary of
the literature on the Indiana bat, especially that pertaining to summer
distribution of reproductive individuals.

[Historic Abundance]{.underline}

With the arrival of European settlers in the central portion of the
Indiana bat's range in the late 1700s and early 1800s, land conditions
and natural resource usage began to change dramatically (Parker and
Ruffner 2004) and undoubtedly affected the species local and presumably
regional abundance. For example, abundance of hibernating bat
populations almost certainly declined after settlers discovered large
deposits of nitrates or saltpeter, essential for making gunpowder, and
began year-round mining operations within some of the major hibernacula.
Saltpeter mining operations at Mammoth Cave, Kentucky, Wyandotte Cave,
Indiana, and other Indiana bat hibernacula peaked during the War of 1812
and generally ended shortly after the war. Most historic accounts about
winter bat populations in caves during this period are anecdotal and
only offer an idea of the species' relative abundance. By the 1820s,
tourism had become lucrative at several major hibernacula and increased
rapidly over the next 100 years. In October 1850, biologist Benjamin
Silliman, Jr. of Yale University visited Mammoth Cave, made detailed
observations, and reported that \"bats are numerous in the avenues
within a mile or two of the mouth of the cave. We found countless groups
of them on the ceilings\" (Silliman et al. 1851, Tuttle 1997). Mammoth
Cave, alone, still held "millions" of bats in 1850 (it has been assumed
many were Indiana bats) after being subjected to severe winter
disturbance from saltpeter mining, tourism, and adverse impacts
associated with cave entrance alterations and restricted airflow (Tuttle
1997).

[Categorization of Hibernacula]{.underline}[^1]

In the Indiana Bat Recovery Plan (Service 1983), Indiana bat hibernacula
are assigned priority numbers based on the number of Indiana bats they
contain. Originally a Priority 1 (P1) hibernaculum is a site that has
contained 30,000 or more Indiana bats since 1960. During a meeting
between the Service and the members of the Indiana bat Recovery Team in
November 2005, a decision was made to revise the existing hibernacula
priority definitions in the forth-coming revised Indiana Bat Recovery
Plan. Although not yet in effect, the hibernacula priority definitions
that will be proposed will have the goal of achieving a wider and more
even distribution of essential hibernation sites across the species'
range. Until proposed, however, the current hibernacula categories will
remain in-effect and are used in this biological opinion.

The P1 population criterion will be lowered from 30,000 bats to 10,000
and the "since 1960" part of all the hibernacula definitions will be
omitted. These changes will effectively increase the number of P1
hibernacula from 11 sites in four states to 23 sites in seven states.
Likewise, the population criteria will also be changed for Priority 2,
3, and 4 hibernacula. On a case-by-case basis, the Service may consider
elevating a particularly important (i.e., "essential") Priority 2 (P2)
hibernaculum (e.g., one that holds a key geographic
location/distribution within the range or very high regional importance)
to P1 status, even though it may not meet the P1 population criteria at
that time. As of October 2006, no P2 hibernacula had been elevated to P1
status in this manner. The revised hibernacula priority numbers and
other new subcategories are defined below. The Service expects to
publish these categories in the revised recovery plan soon.

[Priority 1 (P1)]{.underline}: P1 hibernacula are essential to recovery
and long-term conservation of *M. sodalis*. P1 hibernacula typically
have (1) a current and/or historically observed winter population
greater than or equal to 10,000 Indiana bats and (2) currently have
suitable and stable microclimates (e.g., they are not considered
"ecological traps" as defined below). Priority 1 hibernacula are further
divided into one of two subcategories, "A" or "B," depending on their
recent population sizes. Priority 1A (P1A) hibernacula are those that
have held 5,000 or more Indiana bats during one or more winter surveys
conducted during the past 10 years. In contrast, Priority 1B (P1B)
hibernacula are those that have sheltered ≥ 10,000 Indiana bats at some
point in their past, but have consistently contained fewer than 5,000
bats over the past 10 years.

![](media/image3.jpeg){width="6.491666666666666in"
height="8.225694444444445in"}

**Figure 3.** Distribution of counties with known summer and winter
records of the Indiana bat.

[Priority 2 (P2)]{.underline}: P2 hibernacula contribute to recovery and
long-term conservation of *M. sodalis*. Priority 2 hibernacula have a
current or observed historic population of 1,000 or greater but fewer
than 10,000 and an appropriate microclimate.

[Priority 3 (P3)]{.underline}: P3 hibernacula contribute less to
recovery and long-term conservation of *M. sodalis*. Priority 3
hibernacula have current or observed historic populations of 50-1,000
bats.

[Priority 4 (P4)]{.underline}: P4 hibernacula are least important to
recovery and long-term conservation of *M. sodalis*. Priority 4
hibernacula typically have current or observed historic populations of
fewer than 50 bats.

[High Potential (HP)]{.underline}: HP is a special designation given to
P2, P3, or P4 hibernacula that are deemed capable of supporting 10,000
or more Indiana bats in the future if (1) an appropriate microclimate is
restored (or created, as in the case of some mines) and/or (2) the site
is protected from disturbance. These sites typically have no recorded
direct observations of significant numbers of *M. sodalis* (i.e., at
least none that can be readily confirmed, so they differ from a P1B site
in this respect). Instead most "high-potential" hibernacula have one or
more forms of indirect evidence indicating previous use by large numbers
of *Myotis* and/or *M. sodalis* (e.g., anecdotal historic accounts
and/or paleontological evidence such as bones, mummified remains,
ceiling staining, etc.). As of October 2006, two caves had been
designated as HP: Mammoth Cave in Kentucky and Rocky Hollow Cave in
Virginia.

[Ecological Trap (ET)]{.underline}: An ET is a hibernaculum having a
history of repeated flooding or severe freezing events that have
resulted in the mortality of most hibernating *M. sodalis*. Hibernacula
with other environmental conditions that pose a severe and/or imminent
threat to the majority of hibernating bats may also be designated as
"ecological traps" (e.g., threat of catastrophic collapse). As of
October 2006, three caves had been preliminarily designated as ETs: Bat
Cave (Shannon Co.) in Missouri (freezing), Haile's Cave in New York
(flooding), and Clyfty Cave in Indiana (flooding). These preliminary
designations were made based on the recommendations of Indiana bat
experts familiar with these caves, and on the history of known Indiana
bat mortality in these caves. The designations will be reevaluated when
procedures for evaluation and designation of hibernacula as ETs are
developed.

[Current Winter Distribution]{.underline}

As of November 2006, the Service has winter records of extant (existing)
winter populations (i.e., positive winter occurrence since 1995) of the
Indiana bat at about 281 different hibernacula located in 19 states
(Service, unpublished data, 2006) (Table 1, Figures 3 and 4). Likewise,
based on the 2005 winter surveys, there were 23 Priority 1 hibernacula
in seven states: Illinois (n=1), Indiana (n=7), Kentucky (n=5), Missouri
(n=6), New York (n=2), Tennessee (n =1), and West Virginia (n=1) (Table
1, Table 2, Figure 4). Fifty-three Priority 2 hibernacula are known from
the aforementioned states, as well as Arkansas, Ohio, Pennsylvania, and
Virginia (Table 1, Figure 4). One hundred fifty (150) Priority 3
hibernacula have been reported in 16 states (Table 1, Figure 4). Two
hundred thirteen (213) Priority 4 hibernacula have been reported in 23
states (Table 1, Figure 4). Some records from the periphery of the range
likely represent occasional occupations rather than viable winter
populations (Service 1983). For example, only a single winter record of
a single Indiana bat has been recorded in Florida and Wisconsin despite
multiple winter surveys conducted over several decades (Service,
unpublished data, 2006).

**Table 1.** Distribution and priority numbers of Indiana bat
hibernacula by state.

  --------------- ------------- -------- --------- --------- ------- ---------------- ---------------
                  **Number of                                        **Total Number   **Total Number
                  Hibernacula                                        of**             of
                  by Priority                                                         Hibernacula**
                  Number^1^\                                                          
                  **(Number                                                           
                  with positive                                                       
                  occurrence                                                          
                  since 1995)                                                         

  **\             **\           **\      **\       **\       **\     **Hibernacula\   **with
  \               \             \        \         \         \       with Any         "Extant"\
  State**         P1**          P2**     P3**      P4**      ET**    Previous\        Winter
                                                                     Winter Record**  Populations\
                                                                                      **(≥1 bat since
                                                                                      1995)

  Alabama         \-            \-       2 (1)     8 (4)     \-      10               5

  Arkansas        \-            4 (3)    12 (9)    18 (2)    \-      34               14

  Connecticut     \-            \-       1 (0)     1 (1)     \-      2                1

  Florida         \-            \-       \-        1 (0)     \-      1                0

  Georgia         \-            \-       \-        2 (0)     \-      2                0

  Illinois        1 (1)         6 (6)    7 (6)     8 (3)     \-      22               16

  Indiana         7 (7)         1 (1)    16 (16)   12 (9)    1 (1)   37               34

  Iowa            \-            \-       \-        2 (0)     \-      2                0

  Kentucky        5 (5)         15 (15)  39 (34)   50 (20)   \-      109              74

  Maryland        \-            \-       \-        4 (3)     \-      4                3

  Massachusetts   \-            \-       1 (0)     \-        \-      1                0

  Michigan        \-            \-       \-        1 (1)     \-      1                1

  Missouri        6 (6)         10 (7)   24 (18)   26 (8)    1 (1)   67               40

  New Jersey      \-            \-       2 (2)     1 (0)     \-      3                2

  New York        2 (2)         4 (4)    3 (3)     5 (2)     1 (1)   15               12

  North Carolina  \-            \-       \-        3 (1)     \-      3                1

  Ohio            \-            1 (1)    1 (1)     5 (0)     \-      7                2

  Oklahoma        \-            \-       \-        3 (2)     \-      3                2

  Pennsylvania    \-            2 (1)    5 (3)     18 (7)    \-      25               11

  Tennessee       1 (1)         6 (3)    16 (13)   11 (4)    \-      34               21

  Vermont         \-            \-       5 (3)     1 (0)     \-      6                3

  Virginia        \-            3 (3)    5 (5)     8 (4)     \-      16               12

  West Virginia   1 (1)         1 (1)    11 (11)   24 (14)   \-      37               27

  Wisconsin       \-            \-       \-        1 (0)     \-      1                0

  Total           **23**        **53**   **150**   **213**   **3**   **442**          **281**
  --------------- ------------- -------- --------- --------- ------- ---------------- ---------------

^1^ P1: ≥10,000 bats. P2: 1,000-9,999 bats. P3: 50-999 bats. P4: 1-49
bats. ET: Ecological Trap.

Even though hibernating Indiana bats were dispersed across 16 states in
2005, over 90 percent of the estimated range-wide population hibernated
in five states: Indiana (45.2%), Missouri (14.2%), Kentucky (13.6%),
Illinois (9.7%), and New York (9.1%) (Service, unpublished data, 2006).
In 2005, 81.9 percent (374,653 bats) of the range-wide winter population
hibernated in P1 hibernacula (n=23), while P2 (n=53), P3 (n=150), and P4
(n=213) sheltered 14.4%, 3.3% and 0.4% of the total population,
respectively (Service, unpublished data, 2006). The ten most populous
hibernacula in 2005 collectively held 71.6 percent of the range-wide
total with Wyandotte Cave in southern Indiana leading the list with
54,913 bats (12.0% of total) (Service, unpublished data, 2006) (Table
2).

**Table 2.** Winter population estimates through time for P1A (n=16) and
P1B (n=7) Indiana bat hibernacula. All P1 hibernacula (n=23) have at
some point in the recorded past had ≥10,000 hibernating Indiana bats and
currently provide suitable winter habitat. P1A hibernacula have
maintained a minimum of 5,000 Indiana bats during the last 10 years,
whereas P1B hibernacula have not met this criterion in the last 10+
years.

+---+--------+------------------+---+-------+-------+-------+-------+
| * | **Co   | **Hibernaculum   | > | *     | *     | *     | *     |
| * | unty** | Name**           |   | *Max. | *Max. | *Max. | *Curr |
| S |        |                  | * | Pop.\ | Pop.\ | Pop.\ | ent/\ |
| t |        |                  | * | Esti  | Esti  | Esti  | 2005  |
| a |        |                  | P | mate\ | mate\ | mate\ | Pop.  |
| t |        |                  | r | Since | Since | Since | Estim |
| e |        |                  | i | 1     | 1     | 1     | ate** |
| * |        |                  | o | 960** | 980** | 995** |       |
| * |        |                  | r |       |       |       |       |
|   |        |                  | i |       |       |       |       |
|   |        |                  | t |       |       |       |       |
|   |        |                  | y |       |       |       |       |
|   |        |                  | * |       |       |       |       |
|   |        |                  | * |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| I | Ale    | Magazine Mine    | P | 3     | 3     | 3     | 3     |
| L | xander |                  | 1 | 3,500 | 3,500 | 3,500 | 3,500 |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| I | Cr     | Batwing Cave     | P | 5     | 2     | 1     | 6,850 |
| N | awford |                  | 1 | 0,000 | 9,960 | 0,125 |       |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| I | Cr     | Wyandotte Cave   | P | 5     | 5     | 5     | 5     |
| N | awford |                  | 1 | 4,913 | 4,913 | 4,913 | 4,913 |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| I | Greene | Ray\'s Cave      | P | 6     | 6     | 6     | 5     |
| N |        |                  | 1 | 2,464 | 2,464 | 2,464 | 4,325 |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| I | Ha     | Jug Hole Cave    | P | 2     | 2     | 2     | 2     |
| N | rrison |                  | 1 | 9,430 | 9,430 | 9,430 | 9,430 |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| I | Ha     | Twin Domes Cave  | P | 10    | 9     | 7     | 3     |
| N | rrison |                  | 1 | 0,000 | 8,250 | 8,875 | 6,800 |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| I | Monroe | Coon Cave        | P | 1     | 1     | 1     | 9,270 |
| N |        |                  | 1 | 0,675 | 0,675 | 0,675 |       |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| I | Monroe | Grotto Cave      | P | 1     | 1     | 1     | 9,875 |
| N |        |                  | 1 | 0,338 | 0,338 | 0,338 |       |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| K | Carter | Bat Cave         | P | 10    | 5     | 3     | 2     |
| Y |        |                  | 1 | 0,000 | 1,500 | 1,400 | 9,500 |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| K | Ed     | Dixon Cave       | P | 1     | 1     | 7,200 | 3,100 |
| Y | monson |                  | 1 | 6,550 | 6,550 |       |       |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| M | Iron   | Pilot Knob Mine  | P | 13    | 9     | 5     | 5     |
| O |        |                  | 1 | 9,000 | 4,775 | 0,550 | 0,550 |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| M | Wash   | Great Scott Cave | P | 8     | 8     | 1     | 6,450 |
| O | ington |                  | 1 | 5,700 | 5,700 | 4,850 |       |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| N | Ulster | Walter Wm. Pres. | P | 1     | 1     | 1     | 1     |
| Y |        | Mine             | 1 | 1,394 | 1,394 | 1,394 | 1,394 |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| N | Ulster | Williams Hotel   | P | 1     | 1     | 1     | 1     |
| Y |        | Mine             | 1 | 5,438 | 5,438 | 5,438 | 5,438 |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| T | Blount | White Oak        | P | 1     | 1     | 7,861 | 7,861 |
| N |        | Blowhole Cave    | 1 | 2,500 | 2,500 |       |       |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| W | Pen    | Hellhole Cave    | P | 1     | 1     | 1     | 1     |
| V | dleton |                  | 1 | 1,890 | 1,890 | 1,890 | 1,890 |
|   |        |                  | A |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| K | Ed     | Coach Cave       | P | 10    | 600   | 101   | 0     |
| Y | monson |                  | 1 | 0,000 |       |       |       |
|   |        |                  | B |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| K | Ed     | Long Cave        | P | 7,600 | 7,527 | 1,153 | 1,153 |
| Y | monson |                  | 1 |       |       |       |       |
|   |        |                  | B |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| K | L      | Line Fork Cave   | P | 1     | 8,379 | 1,863 | 1,844 |
| Y | etcher |                  | 1 | 0,000 |       |       |       |
|   |        |                  | B |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| M | Cr     | Onyx Cave        | P | 1     | 8,994 | 380   | 180   |
| O | awford |                  | 1 | 2,850 |       |       |       |
|   |        |                  | B |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| M | Fr     | Copper Hollow    | P | 2     | 9,295 | 250   | 250   |
| O | anklin | Sink Cave        | 1 | 1,000 |       |       |       |
|   |        |                  | B |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| M | P      | Brooks Cave      | P | 1     | 1     | 750   | 70    |
| O | ulaski |                  | 1 | 9,461 | 1,850 |       |       |
|   |        |                  | B |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+
| M | P      | Ryden Cave       | P | 1     | 5,800 | 40    | 10    |
| O | ulaski |                  | 1 | 0,539 |       |       |       |
|   |        |                  | B |       |       |       |       |
+---+--------+------------------+---+-------+-------+-------+-------+

![](media/image4.png){width="6.488194444444445in"
height="8.240277777777777in"}

**Figure 4.** Distribution of counties with known Indiana bat
hibernacula records and their current priority numbers. Note: For
counties with multiple hibernacula with different priority numbers, only
the color of the highest priority hibernacula is shown.

In the 1960s and 1970s, 75% of the known range-wide population
hibernated in the southern portion of the species' winter range (i.e.,
Kentucky and Missouri) (Clawson 2002). However, by 2001 and through
2005, 60% of remaining Indiana bats occupied hibernacula in the (more or
less) northern portion of the winter range (Table 3). Few specific
drivers of this apparent population shift have been rigorously explored
or identified, but inappropriate hibernacula temperatures (see Tuttle
and Kennedy 2002) and regional climate change are either known or
generally suspected in having had a role. We have an incomplete
understanding of the links among *M. sodalis*' hibernation energetics,
its biogeographical distribution, and climate change. However, the
predictive modeling approach recently used by Humphries et al. (2002)
for *M. lucifugus* could provide some insight into *M. sodalis*'
potential winter distribution as global climate change occurs.

In at least three known cases, the species has expanded its winter range
beyond its historic winter limits because of occupying man-made
hibernacula (e.g., mines, tunnels, a dam) in relatively recent times.
Some occupied man-made structures are relatively far removed from
natural cave areas (e.g., Black Ball Mine in northern Illinois,
Lewisburg Limestone Mine in west central Ohio, Tippy Dam near the
eastern border of Lake Michigan in Michigan). Of the 33 mines with
extant winter populations (i.e., one or more positive records since
1995), some have served as hibernacula for Indiana bats for nearly a
century or more (e.g., Pilot Knob Mine in Missouri) (Clawson 2002).
Others, where mining activities have been abandoned more recently, have
only supported significant winter populations within the past decade,
such as the Magazine Mine in southern Illinois (Kath 2002). These
findings suggest that Indiana bats are capable of expanding their winter
distribution by colonizing suitable hibernacula as they become available
within and near their traditional winter range. In 2005, about 30
percent (136,410 bats) of the range-wide population of Indiana bats
hibernated in man-made hibernacula (24 mines, one dam, and one tunnel)
and the other 70 percent (320,964 bats) hibernated in natural caves
(Service, unpublished data, 2006). In addition, it appears in some
instances that Indiana bats may redistribute themselves over several
years as evidenced by population declines in some hibernacula that
coincided with population increases at others nearby (e.g., Twin Domes
and Wyandotte caves in Indiana) (Service, unpublished data, 2006). Such
rapid increases cannot be attributed to reproduction alone and are due,
at least in part, to immigration.

Emigration and immigration of bats between regional hibernacula occurs,
but a detailed characterization or quantification of these movements has
not been made. Initial observations of local and regional winter
population dynamics suggest Indiana bat winter populations likely follow
some form of a metapopulation model (Hanski 1998, Cronin 2003). While
records of short and long-distance movements of banded bats between
caves have been known (Hall 1962), only recently has genetic analysis
been used to determine the relative degree of gene flow occurring among
and between winter populations.

[Current Winter Population Groups]{.underline}

Vonhof and McCracken's statistical analysis of genetic samples (mtDNA
extracted from wing membrane punches) (Vonhof, pers. comm., 2006)
collected from hibernating Indiana bats from widely dispersed
hibernacula suggested that genetic variance among samples was best
explained by dividing sampled hibernacula (n=13) into four separately
defined population groups, as follows:

**Table 3.** Size and distribution of hibernating populations of the
Indiana bat by region and state, based upon estimates nearest to the
year indicated.^1^

+---+----------------+-------+-------+-------+-------+-------+-------+
|   | **State**      | **1   | **1   | **1   | **2   | **2   | **2   |
|   |                | 965** | 980** | 990** | 001** | 003** | 005** |
+---+----------------+-------+-------+-------+-------+-------+-------+
| > | Alabama        | 350   | 350   | 350   | 250   | 317   | 296   |
|   |                |       |       |       |       |       |       |
| * |                |       |       |       |       |       |       |
| S |                |       |       |       |       |       |       |
| o |                |       |       |       |       |       |       |
| u |                |       |       |       |       |       |       |
| t |                |       |       |       |       |       |       |
| h |                |       |       |       |       |       |       |
| e |                |       |       |       |       |       |       |
| r |                |       |       |       |       |       |       |
| n |                |       |       |       |       |       |       |
| > |                |       |       |       |       |       |       |
|   |                |       |       |       |       |       |       |
| R |                |       |       |       |       |       |       |
| e |                |       |       |       |       |       |       |
| g |                |       |       |       |       |       |       |
| i |                |       |       |       |       |       |       |
| o |                |       |       |       |       |       |       |
| n |                |       |       |       |       |       |       |
| * |                |       |       |       |       |       |       |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Arkansas       | 1     | 1     | 4,500 | 2,476 | 2,124 | 2,067 |
|   |                | 5,000 | 5,000 |       |       |       |       |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Illinois       | 1     | 1     | 1     | 1     | 3     | 4     |
|   | (southern)     | 4,700 | 4,700 | 4,500 | 9,491 | 2,330 | 2,539 |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Kentucky       | 24    | 10    | 7     | 5     | 4     | 6     |
|   |                | 8,100 | 2,200 | 8,700 | 0,047 | 7,876 | 2,380 |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Missouri       | 39    | 34    | 15    | 7     | 6     | 6     |
|   |                | 9,000 | 2,000 | 0,100 | 2,983 | 6,805 | 5,104 |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Oklahoma       | 0     | 0     | 0     | 0     | 5     | 5     |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Tennessee      | 2     | 2     | 1     | 1     | 8,900 | 9,971 |
|   |                | 0,100 | 0,100 | 6,400 | 0,172 |       |       |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Virginia       | 3,100 | 2,500 | 1,900 | 833   | 1,090 | 735   |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Subtotal       | 70    | 49    | 26    | 15    | 15    | 18    |
|   |                | 0,350 | 6,850 | 6,450 | 6,252 | 9,447 | 3,097 |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | \% of          | 79.3% | 73.2% | 56.3% | 41.0% | 40.0% | 40.0% |
|   | Rangewide      |       |       |       |       |       |       |
|   | Total          |       |       |       |       |       |       |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   |                |       |       |       |       |       |       |
+---+----------------+-------+-------+-------+-------+-------+-------+
| > | Illinois       | 100   | 100   | 400   | 1562  | 1648  | 1804  |
|   | (Blackball     |       |       |       |       |       |       |
| * | Mine)          |       |       |       |       |       |       |
| N |                |       |       |       |       |       |       |
| o |                |       |       |       |       |       |       |
| r |                |       |       |       |       |       |       |
| t |                |       |       |       |       |       |       |
| h |                |       |       |       |       |       |       |
| e |                |       |       |       |       |       |       |
| r |                |       |       |       |       |       |       |
| n |                |       |       |       |       |       |       |
| > |                |       |       |       |       |       |       |
|   |                |       |       |       |       |       |       |
| R |                |       |       |       |       |       |       |
| e |                |       |       |       |       |       |       |
| g |                |       |       |       |       |       |       |
| i |                |       |       |       |       |       |       |
| o |                |       |       |       |       |       |       |
| n |                |       |       |       |       |       |       |
| * |                |       |       |       |       |       |       |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Indiana        | 16    | 15    | 16    | 17    | 18    | 20    |
|   |                | 0,300 | 5,200 | 3,500 | 3,076 | 3,332 | 6,610 |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Michigan       | 0     | 0     | 0     | 20    | 20    | 20    |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | New Jersey     | 0     | 0     | 0     | 107   | 644   | 652   |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | New York       | 2     | 2     | 2     | 2     | 3     | 4     |
|   |                | 0,200 | 1,100 | 6,800 | 9,746 | 2,924 | 1,702 |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Ohio           | 150   | 3,600 | 9,500 | 9,788 | 9,436 | 9,769 |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Pennsylvania   | 700   | 700   | 400   | 702   | 853   | 746   |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Vermont        | 0     | 0     | 0     | 159   | 175   | 297   |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | West Virginia  | 1,500 | 1,200 | 6,500 | 9,744 | 9,741 | 1     |
|   |                |       |       |       |       |       | 2,677 |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Subtotal       | 18    | 18    | 20    | 22    | 23    | 27    |
|   |                | 2,950 | 1,900 | 7,100 | 4,904 | 8,773 | 4,277 |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | \% of          | 20.7% | 26.8% | 43.7% | 59.0% | 60.0% | 60.0% |
|   | Rangewide      |       |       |       |       |       |       |
|   | Total          |       |       |       |       |       |       |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   |                |       |       |       |       |       |       |
+---+----------------+-------+-------+-------+-------+-------+-------+
|   | Grand Total    | 88    | 67    | 47    | 38    | 39    | 45    |
|   |                | 3,300 | 8,750 | 3,550 | 1,156 | 8,220 | 7,374 |
+---+----------------+-------+-------+-------+-------+-------+-------+

> ^1^Not all surveys occurred exactly as portrayed in the table.
> Population estimates for a particular period were based on the survey
> nearest to the year indicated, either prior to or subsequent to that
> year, so that all caves are represented in each period.

-   Midwest, included sampled populations in AR, MO, IN, KY, OH,
    Cumberland Gap Saltpeter Cave in southwestern VA, and Jamesville
    Quarry Cave in Onondaga Co., NY,

-   Appalachia, included White Oak Blowhole Cave in east TN, and
    Hellhole Cave in WV,

-   Northeast 1 (NE1), included Barton Hill Mine and Glen Park Caves in
    northern NY (Essex and Jefferson counties, respectively), and

-   Northeast 2 (NE2), included Walter Williams Preserve Mine in Ulster
    Co., NY.

Vonhof and McCracken's other findings and conclusions included:

-   Most winter populations had a high haplotype and nucleotide
    diversity,

-   Low genetic diversity in 3 of the 4 winter populations sampled in
    NY,

-   Some level of male- and/or female-mediated gene flow was occurring
    among 3 of the 4 defined groups (Midwest, Appalachia, and NE2), but
    apparently there was no gene flow for either sex between the NE1
    group and the other groups.

-   The low levels of genetic diversity in NE1 and NE2 (i.e., a severe
    genetic "bottleneck"), are indicative of relatively recent
    colonization of the Northeast within historical times (e.g.,
    estimated at 153 years before present for NE1) by a small number of
    individuals.

Interestingly, these recent findings also agree with Hall's (1962)
taxonomic studies of over 1,000 museum specimens collected from
throughout the Indiana bat's range. Hall noticed that Vermont specimens
tended to have more distinct banding of the fur, longer hairs on the
feet, and that their skulls had significantly narrower nasal breadth
than those in other parts of the range. He stated "if the establishment
of populational ranges has acted as an isolating mechanism, it has not
produced any noticeable variation, except in the case of the northeast
population." Hall concluded that "the establishment of populational
ranges restricts gene flow within the species" and that "this apparently
has not been in effect long enough to allow race differentiation to
occur."

[Current Summer Distribution]{.underline}

*Maternity Colonies*

The first Indiana bat maternity colony was not discovered until 1971 (in
east-central Indiana, Cope et al. 1974). As of October 2006, we have
records of 269 maternity colonies in 16 states that are considered
locally extant (Table 4). Of the 269 colonies, 54 percent (n=146) have
been found (mostly during mist-netting surveys) within the past 10 years
(i.e., since 1997) (Table 4, Figure 5). Because maternity colonies are
widely dispersed during the summer and difficult to locate, it is
presumed that all the combined summer survey efforts have found only a
fraction of the maternity colonies based on the range-wide population
estimates derived from winter hibernacula surveys. For example, based on
the 2005 range-wide population estimate of 457,374 bats, and assuming a
50:50 sex ratio and an average maternity colony size of 50 to 80 adult
females (Whitaker and Brack 2002), then the 269 maternity colonies in
Table 4 may only represent 6 to 9 percent of the 2,859 to 4,574
maternity colonies we would assume exist. Regardless of reasonable
disagreements on the average colony size, the geographic locations of
the majority of Indiana bat maternity colonies remain unknown.

**Table 4.** States and counties with recorded Indiana bat maternity
colonies**.**^1,2,3^ These colonies are considered likely to be locally
extant (within limits of data noted in footnote 3).

+-----------+--------+-------------------------------------------------+
| **\       | **No.  | **\                                             |
| \         | of     | \                                               |
| \         | Re     | Counties with Recorded Maternity Colonies**     |
| State**   | corded |                                                 |
|           | Mat    | (if multiple colonies, then \# is shown)        |
|           | ernity |                                                 |
|           | Colo   |                                                 |
|           | nies** |                                                 |
+-----------+--------+-------------------------------------------------+
| Arkansas  | 1      | Clay                                            |
+-----------+--------+-------------------------------------------------+
| Illinois  | 28     | Adams (2), Alexander, Bond, Cass, Ford,         |
|           |        | Henderson, Jackson (3), Jersey, Macoupin,       |
|           |        | Monroe (4), Pike (2), Pulaski, Randolf, Saline, |
|           |        | Schuyler, Scott, St. Clair, Union, Vermilion,   |
|           |        | and Washington (2)                              |
+-----------+--------+-------------------------------------------------+
| Indiana   | 83     | Bartholomew (3), Clinton (2), Crawford, Davies  |
|           |        | (2), Dearborn, Gibson (2), Greene (3),          |
|           |        | Hendricks (2), Henry, Howard, Huntington,       |
|           |        | Jackson (3), Jasper, Jay, Jefferson (2),        |
|           |        | Jennings (2), Johnson (3), Knox, Koskiusko,     |
|           |        | LaPorte (2), Marion, Martin, Monroe (2),        |
|           |        | Montgomery (3), Morgan (4), Newton, Parke (2),  |
|           |        | Perry (2), Pike (2), Posey, Pulaski (2), Putnam |
|           |        | (2), Randolph (3), Ripley (2), Rush, Shelby     |
|           |        | (2), Spencer, St. Joseph, Steuben, Tippecanoe   |
|           |        | (4), Vermillion, Vigo, Wabash (2), Warren (2),  |
|           |        | Warrick (2), Wayne, and Wells                   |
+-----------+--------+-------------------------------------------------+
| Iowa      | 27     | Appanoose (2), Davis, Decatur (2), Des Moines   |
|           |        | (2), Iowa, Jasper, Keokuk, Lucas (2), Madison   |
|           |        | (2), Marion (7), Monroe, Ringgold, Van Buren,   |
|           |        | Wapello, and Washington (2)                     |
+-----------+--------+-------------------------------------------------+
| Kentucky  | 32     | Ballard, Ballard/Carlisle, Bath (3),            |
|           |        | Breckinridge, Bullitt (4), Daviess, Edmonson    |
|           |        | (3), Floyd, Harlan (3), Henderson (2), Hickman  |
|           |        | (2), Jefferson (3), Logan, McCracken (2),       |
|           |        | Pulaski, Rowan, Spencer, and Union              |
+-----------+--------+-------------------------------------------------+
| Maryland  | 2      | Carroll (2)                                     |
+-----------+--------+-------------------------------------------------+
| Michigan  | 11     | Calhoun, Cass, Eaton, Hillsdale, Jackson,       |
|           |        | Lenawee (2), Livingston, St. Joseph (2), and    |
|           |        | Van Buren                                       |
+-----------+--------+-------------------------------------------------+
| Missouri  | 20     | Chariton, Gasconade, Iron, Jefferson, Knox (2), |
|           |        | Lewis, Linn, Macon, Madison, Marion, Mercer,    |
|           |        | Monroe, Nodaway, Pulaski, Scotland, St.         |
|           |        | Francois, St. Genevieve, Sullivan, and Wayne    |
+-----------+--------+-------------------------------------------------+
| New       | 7      | Morris (5), Somerset, and Sussex                |
| Jersey    |        |                                                 |
+-----------+--------+-------------------------------------------------+
| New York  | 31     | Cayuga, Dutchess (5), Essex, Jefferson (9),     |
|           |        | Onondaga (4), Orange (8), and Oswego (3)        |
+-----------+--------+-------------------------------------------------+
| Ohio      | 11     | Ashtabula, Butler, Clermont, Cuyahoga, Greene,  |
|           |        | Hocking, Lawrence, Paulding, Pickaway, Summit,  |
|           |        | and Wayne                                       |
+-----------+--------+-------------------------------------------------+
| Pen       | 2      | Berks and Blair                                 |
| nsylvania |        |                                                 |
+-----------+--------+-------------------------------------------------+
| Tennessee | 3      | Blount (2) and Monroe                           |
+-----------+--------+-------------------------------------------------+
| Vermont   | 7      | Addison (6) and Chittenden                      |
+-----------+--------+-------------------------------------------------+
| Virginia  | 1      | Lee                                             |
+-----------+--------+-------------------------------------------------+
| West      | 3      | Boone (2) and Tucker                            |
| Virginia  |        |                                                 |
+-----------+--------+-------------------------------------------------+
| **Total** | *      |                                                 |
|           | *269** |                                                 |
+-----------+--------+-------------------------------------------------+

^1^ Unpublished data obtained in response to a data request sent to
Service Field Offices in February 2006.

^2^ Most maternity colony records were based upon the capture of
reproductively active females and/or juveniles between 15 May and 15
August.

^3^ This table includes records of maternity colonies considered to be
locally extant (even though records may not have been verified in recent
years). Although some additional records exist, we did not include them
if subsequent surveys failed to detect their presence (i.e., the colony
may have disbanded, relocated, was extirpated, or was present but not
found). Records were also not included if suitable habitat no longer
exists at a previously occupied site.

![](media/image5.png){width="6.472222222222222in"
height="8.208333333333334in"}

**Figure 5.** Distribution of counties with known summer reproductive
records of Indiana bats (i.e., presence of reproductively active females
and/or juveniles between 15 May and 15 August). Lack of records does not
necessarily mean the species is not present.

Most capture records of reproductively active female and juvenile
Indiana bats (i.e., evidence of a nearby maternity colony) have occurred
in glaciated portions of the upper Midwest including southern Iowa,
northern Missouri, much of Illinois, most of Indiana, southern Michigan,
and western Ohio, and in Kentucky. However, a growing number of
maternity records have been documented in New York, New Jersey, and
Vermont recently due to spring emergence studies and mist netting
efforts (Gardner and Cook 2002; Service, unpublished data, 2006) (Table
4; Figure 5). The more rugged, unglaciated portions of the Midwest
(Ozarks/southern Missouri, parts of southern Illinois, and south-central
Indiana), Kentucky, and most of the eastern and southern portions of the
species' range appear to have fewer maternity colonies per unit area of
forest than does the upper Midwest. Additional summer survey efforts and
spring emergence studies will be needed in some areas, particularly
along the periphery of the range, before conclusions may be reached on
the extent of the species' summer range. Likewise, a comprehensive
analysis of existing positive and negative summer survey data is
warranted.

Although Indiana bat maternity colonies occur throughout much of the
mid-eastern United States (e.g., West Virginia, Virginia, Pennsylvania,
New York), they appear to be relatively less abundant than in the
Midwest or more central portion of the range. This apparent regional
difference in summer distribution and relative abundance, especially of
maternity colonies, may be influenced in large part by geographic
distribution of important hibernacula and by regional differences in
climate and elevation. During the summer, higher latitudes and
elevations typically are cooler and wetter, and temperatures at higher
elevations are more variable, adding significantly to the cost of
reproduction (Brack et al. 2002). In short, our understanding of how and
to what extent distribution of hibernacula and local and regional
climate and elevation differences influence the distribution and
abundance of maternity colonies is still evolving.

*Adult Males*

Male Indiana bats are found throughout the range of the species, but in
summer are most common in areas near hibernacula (Hall 1962, Gardner and
Cook 2002, Figure 5). Please refer to the Life History and Summer
Habitat sections for additional information.

[Current Abundance]{.underline}

By compiling individual population estimates from bat surveys conducted
within 214 hibernacula during the winters of 2003-2004 and 2004-2005,
the Service has estimated that the Indiana bat's 2005 range-wide
population was approximately 457,000 bats (Service, unpublished data,
2006) (Table 3).

In 2005, 82 percent of the range-wide population hibernated within 22 of
the 23 Priority 1 hibernacula (Table 2). Thirteen of the 23 Priority 1
hibernacula have been surveyed every 2 years from 1983 to 2005. Due to
hazardous conditions within Pilot Knob Mine in Missouri, this P1
hibernaculum cannot be safely entered to conduct a standard winter
survey. Fall trapping rates at the entrance to this mine, however, have
shown that large numbers of bats continue to use it (Clawson 2002).
Although it is not feasible to confirm, bat surveyors are aware of some
hibernacula that have physically inaccessible areas. These hibernacula
range in size from small cracks and crevices to large rooms where
Indiana bats are known or believed to roost. In these situations, our
population estimates may be viewed as conservative (i.e., under
estimations).

In most winters, a few new hibernacula are discovered, but most of these
contain less than 1,000 Indiana bats (i.e., P3) and many contain less
than 50 bats (i.e., P4) (Service, unpublished data, 2006). Discovery of
new hibernacula with \>1,000 Indiana bats is uncommon, but occasionally
does occur. Of hibernacula first documented during the past 10 years,
only three have held more than 5,000 Indiana bats when initially
discovered: Magazine Mine in Illinois, Lewisburg Limestone Mine in Ohio,
and Williams Hotel Mine in New York. Over the past 25 years, no
hibernaculum has contained more than 10,000 Indiana bats when initially
discovered (Service, unpublished data, 2006).

**Population Trends in Hibernacula**

[Background]{.underline}

During the 1950s, biologists began conducting winter bat surveys at
irregular intervals and recording population estimates for about a dozen
Indiana bat hibernacula (Hall 1962; Service, unpublished data, 2006).
Since that time, hundreds of additional populations of hibernating
Indiana bats have been discovered, and our knowledge of the winter
distribution and status of the species has expanded. Many hibernating
populations have decreased in size since range-wide monitoring began
(Figure 6), especially in Kentucky and Missouri (Table 3). By the time
the status of the Indiana bat was officially recognized in 1967, it is
assumed, the remaining populations represented a portion of historical
numbers. These hibernating populations were often confined to smaller
caves, which likely had less thermal stability, fewer and less optimal
roosting options, and had a higher risk of predation than traditional
hibernacula. By 1985, more than 85 percent of the known, range-wide
population hibernated in just eight caves and one mine.

![](media/image6.wmf){width="6.497916666666667in"
height="3.3993055555555554in"}

**Figure 6.** Indiana bat rangewide population estimates (Data sources:
1965-1990, Clawson 2002; 2001-2005, Service, unpublished data, 2006).
Rangewide estimates calculated from all known hibernacula were not
attempted or data was not available for most years prior to 2001.

During the 1960s and most of the 1970s, winter surveys of the largest
Indiana bat populations known at that time were inconsistent, and many
medium-sized and large winter populations had not yet been discovered.
Since the release of the original Recovery Plan in 1983, with few
exceptions, a standardized survey approach has been used to make
biennial estimates of all known winter bat populations within the most
populous hibernacula (i.e., P1s and P2s).

[Range-wide Population Estimates]{.underline}

Nearly all of the existing range-wide population estimates for the
Indiana bat were generated by simply adding together all available
estimates from traditional winter surveys of all known hibernacula
during a specified period in time. However, if one looks at the actual
proportion of the known hibernacula that were known and/or actually
surveyed during previous decades, it is apparent that range-wide
estimates calculated for any given year prior to about 1980 should be
regarded as approximate. The uncertainty associated with these early
range-wide estimates is relatively high (compared to recent estimates)
due to large, irregular gaps of time between winter surveys, small
number of surveys conducted in any given year, and asynchrony and
non-standardization among the surveys that were conducted (Figure 6).

After standardized surveys of all known P1 hibernacula were initiated in
the 1983, the quality of the range-wide estimates improved. Clawson
(2002) made a reasonable and conservative effort to reduce the amount of
error associated with calculating range-wide estimates (especially for
decades with limited data) by forward- and/or backfilling in the missing
data cells with the same estimates for each individual hibernaculum that
had been recorded during its most recent survey. In a similar manner,
when a "new" P1 or P2 hibernaculum was discovered, Clawson used its
first post-discovery population estimate to backfill the blanks in the
data set for each of the previous time periods being calculated (see
Clawson 2002 for rationale for backward projection of estimates for
newly discovered populations). Again, while such data manipulations were
necessary and undoubtedly improved the accuracy of range-wide population
estimates, the current estimates calculated for years prior to 1980
should be considered as approximate. As an example, more than half of
the bats that were included in the calculation of the range-wide
estimate for the year "1965" in Figure 6 were attributed to hibernacula
that had not yet been discovered, but those bats were assumed to have
been present in those hibernacula prior to discovery of the hibernacula.

[Apparent Long-term Trend]{.underline}

Over the long term, from 1965 to 2001, there has been an overall decline
in Indiana bat numbers, (Figure 6, Service 1983, Kurta and Kennedy
2002). Estimated numbers consistently declined through this period. Even
with the discovery of many new, large hibernacula, the range-wide
population estimate dropped about 57 percent from 1965 to 2001. Since
the advent of systematic attempts to estimate population numbers, some
specific drivers (e.g., changes in cave air flow/temperatures, human
disturbance levels) have been linked to positive and negative trends in
some of the most important hibernacula (see Tuttle and Kennedy 2002),
but the underlying causes of population changes at other hibernacula
remain unknown or incompletely known. The Service's confidence in
apparent positive and negative population trends within individual
hibernacula and collectively in the long-term, range-wide decline
remains relatively high for the following reasons:

1)  Continuity and consistency -- with very few exceptions, the same
    small group of highly qualified biologists have been surveying the
    same caves/mines using consistent survey techniques since
    standardized surveys began in the 1983

2)  Surveyors have demonstrated high levels of attentiveness,
    thoroughness, and scientific integrity while completing the winter
    surveys through the years; and

3)  Other lines of evidence clearly point to large population changes in
    numerous hibernacula.

For example, consistently observed gradual population declines in
numerous regional hibernacula and obvious population crashes (e.g.,
\>50% declines and complete absence of Indiana bats in some cases) in
other traditionally important hibernacula in the same region of the
bat's range (e.g., Missouri, Kentucky) are compelling evidence of a true
decline, regardless of whether statistical significance can be applied
to the numbers.

[Apparent Short-term Trend]{.underline}

Range-wide estimates of species numbers over the three most recent
biennial survey periods do not show the same declining trend seen in
estimates spanning 1965-2000 (Figure 6). There was about a 16 % increase
from the 2003 estimate of 393,000 bats to the rounded estimate of
457,000 bats Service in 2005 (USFWS, unpublished data, 2006) (Table 3;
Figure 6). In spite of some changes in methodology over time and a
general lack of data on the statistical accuracy and variability of
hibernacula estimates, the Service believes that the apparent upward
trend in recent years is real because the same biologists have been
consistently conducting the winter surveys at all of the largest
hibernacula over the past 20 years. This level of surveyor consistency,
coupled with obvious, increases at some high-priority hibernacula in
Indiana, Illinois, Kentucky and New York in recent years (see Table 3),
provides us with some confidence that the long-term decline may have
halted. We anticipate that planned improvements in hibernacula survey
methodology will soon provide for a greater level of confidence in the
overall population trend.

[Apparent Trends by Cave 1965-2005: Missouri, Indiana, and
Kentucky]{.underline}

Missouri, Indiana, and Kentucky have historically had the highest
estimated numbers of hibernating bats (Figure 7); all had estimated
populations of \>100,000 bats in 1965. Over the period 1965-2005,
estimated numbers of hibernating bats in Missouri and Kentucky clearly
declined. Of Missouri hibernacula that were estimated to contain at
least 10,000 bats at least once, all had estimates that declined since
1985, although two hibernacula showed strong increases before that time
(Figure 8). Kentucky hibernacula that sheltered at least 10,000
(estimated) bats at least once had less consistent patterns (Figure 9).
The total number of Indiana bats appears to have declined but trends at
individual hibernacula is generally upward. Indiana bat hibernacula that
had at least one estimate of \>10,000 hibernating bats also showed
little consistency (Figure 10). Four of seven hibernacula seem to show
periods of increase and periods of decrease, including the three
hibernacula with the highest one-time counts. The other three
hibernacula show consistent increases, two of them reaching 10,000 in
the 2003 survey.

![](media/image7.wmf){width="3.904166666666667in"
height="3.408333333333333in"}**Figure 7.** States with the largest
numbers of Indiana bats in hibernacula. For years in which a
hibernaculum was not yet known, the first post-discovery survey results
were used (V. Meretsky, pers. comm., 2006).

![](media/image8.wmf){width="6.492361111111111in" height="3.51875in"}

**Figure 8.** Estimated numbers of Indiana bats in P1A and P1B
hibernacula in Missouri (Service, unpublished data, 2006).

![](media/image9.wmf){width="6.495138888888889in"
height="3.5659722222222223in"}

**Figure 9.** Estimated numbers of Indiana bats in P1A and P1B
hibernacula in Kentucky (Service, unpublished data, 2006).

![](media/image10.wmf){width="6.497916666666667in"
height="3.390972222222222in"}

**Figure 10.** Estimated numbers of Indiana bats in P1A hibernacula in
Indiana (Service, unpublished data, 2006).

[Population Patterns in States with \<100,000 Bats]{.underline}

Among the group of states in which aggregate hibernaculum surveys have
never reached 100,000 bats, hibernaculum surveys in Arkansas, Tennessee,
and Virginia have consistently declined from 1965 to 2000 (Figure 11).
Hibernacula surveys in Illinois, New York, Ohio, and West Virginia are
greater in 2000 than in 1965, but trends are not consistent through the
period. Thus, the southern tier of states in the species' range shows
declines in counts at hibernacula, whereas some states in the northern
tier show increasing counts (Table 3). Connecticut and other states with
very small populations were too small or too recently discovered to show
graphically, and we do not discuss them here.

[Apparent Regional Population Trends and Climate Change]{.underline}

It is nearly impossible to consider the geographic positions of states
where Indiana bat populations are declining and states where they are
stable or increasing without considering the possibility that climate
change or other environmental issue is driving some changes in Indiana
bat populations. Table 3 reveals a clear division in apparent population
trends between states in the northern portion of the Indiana bat's range
versus states in the southern portion of the range (Clawson 2002). Steep
declines in Kentucky and Missouri hibernacula have largely contributed
to the apparent decline in the southern population during the 45-year
period from 1960 through the present. In contrast, there apparently has
been an overall increase in population in northern states over the same
time period. The role of climate change and its effect on temperatures
in hibernacula need investigation. Although current data are not
sufficient to definitively determine the cause of apparent regional
disparities, it appears that both protection of hibernacula and suitable
temperature regimes may be key to understanding trends in the overall
population and recovery of the species.

![](media/image11.wmf){width="4.938194444444444in"
height="3.2090277777777776in"}

**Figure 11.** Estimated numbers of Indiana bats in states with counts
always below 100,000 bats. For years in which a cave was not yet known,
the first survey results for the cave are used. Counts for Alabama,
Massachusetts, Pennsylvania, and Vermont were too small to show at this
scale (Meretsky, pers. comm., 2006).

**Life history**

The Indiana bat is a migratory bat, hibernating in caves and mines in
the winter and migrating to summer habitat. Although some Indiana bat
bachelor colonies have been observed (Hall 1962, Carter et al. 2001),
males and non-reproductive females typically do not roost in colonies
and may stay close to their hibernaculum (Brack 1983, Whitaker and Brack
2002) or migrate long distances to their summer habitat (e.g., Kurta and
Rice 2002). Reproductive females may migrate up to 357 mi (Winhold and
Kurta 2006), to form maternity colonies to bear and raise their young.
Both males and females return to hibernacula in late summer or early
fall to mate and enter hibernation.

[Demographics]{.underline}

Births, immigration, deaths, and emigration reflect the primary
population processes responsible for changes in population size
(Williams et al. 2002). Demographics include those biologically relevant
parameters, such as total population size, age distribution,
age-specific survival, sex ratio, sex-specific survival, and fecundity
or reproductive rate, which influence population change by acting on one
or more of these processes. These parameters are key components in
understanding the extinction risk faced by the Indiana bat. Current
demographic information for this species is mostly unknown.

In temperate-zone insectivorous bats, many young females mate their
first autumn and have offspring the following year, whereas males
usually do not sexually mature until the summer after their birth
(Gustafson 1975, Schowalter et al. 1979, Racey and Entwistle 2000). The
age of reproductive maturity or first breeding is important in
determining reproductive potential (Racey and Entwistle 2003) and is
highly variable in vespertilionids, ranging from 3 to 16 months in both
sexes (Tuttle and Stevenson 1982). Guthrie (1933) reported that female
Indiana bats are sexually mature by the end of their first summer,
although there may be considerable intraspecific variation in the age of
sexual maturity (Racey 1982). Butchkoski and Turner (2006) reported that
one female Indiana bat in a Pennsylvania maternity colony, initially
captured as a juvenile in July 2001 and recaptured each of the next four
summers, did not reproduce until she was three years old. Age of
reproductive maturity likely varies with latitude (Racey and Entwistle
2003). In a review of pertinent literature, Tuttle and Stevenson (1982)
concluded that male vespertilionids rarely attain sexual maturity ahead
of females.

Female Indiana bats, like most temperate vespertilionids, give birth to
one young each year (Mumford and Calvert 1960, Humphrey et al. 1977,
Thomson 1982). Seven pregnant Indiana bats examined by Easterla and
Watkins (1969) had single embryos, supporting conclusions that most
species of bats have low reproductive rates (Herreid 1964, Racey and
Entwistle 2003, Barclay et al. 2004). The proportion of female Indiana
bats that produce young is not well documented. At a colony in Indiana,
23 of 25 female Indiana bats produced volant young during one year, and
28 females produced at least 23 young the following year (Humphrey et
al. 1977). Based on cumulative mist-netting captures over multiple
years, Kurta and Rice (2002) estimated that 89 percent of adult females
in Michigan maternity colonies were in reproductive condition (pregnant,
lactating, or post-lactating). Reproductive rates of the closely related
little brown bat often exceed 95 percent (i.e., 95 percent of females
give birth), but location and environmental factors (e.g., amount of
rainfall and temperature) can lead to lower rates (Kurta and Rice 2002,
Barclay et al. 2004). Many studies of vespertilionid bats showed that
within a species, the proportion of breeding females may vary
dramatically among populations and between years, and this variation is
typically due to climate (Racey and Entwistle 2000, Barclay et al.
2004).

The sex ratio of the Indiana bat is generally reported as equal or
nearly equal, based on early work by Hall (1962), Myers (1964), and
LaVal and LaVal (1980). Humphrey et al. (1977) observed a nearly even
sex ratio (nine females, eight males) in a sample of weaned young
Indiana bats. However, differential survival in adults has been
suggested (Humphrey and Cope 1977, LaVal and LaVal 1980).

No estimates of age structure have been made for winter populations, or
for the population as a whole, due in part to the lack of an accurate
technique for aging individuals once they are adults (Anthony 1988,
Batulevicius et al. 2001). To date, published estimates of the lifespan
of the Indiana bat are based on survival after banding, from bats
captured in winter. Using winter sampling of unknown-age bats over a
23-year period, Humphrey and Cope (1977) estimated annual survival.
Survival rates following weaning are unknown, although Humphrey and Cope
(1977) surmised that the lowest survival occurred in the first year
after marking. Those authors suspected their samples contained many
young-of-the-year, but banding was conducted during the hibernation
period when young were indistinguishable from adults.

Based on banding data, Humphrey and Cope (1977) proposed that the adult
period of life is characterized by two distinct survival phases. The
first is a high and apparently constant rate from 1 to 6 years after
marking with 76 and 70% annual rates for females and males,
respectively. The second phase is a lower constant rate after 6 years
with annual survival of 66 percent for females up to 10 years and 36%
for males. Following 10 years, the survival rate for females dropped to
only 4%. Humphrey and Cope (1977) surmised that this lower rate may
reflect an increased cost of migration and reproduction during old age,
or may be attributable to sampling error, as a very small number of
females remained alive after 10 years. However, individuals have been
noted to live much longer, with the oldest known Indiana bat captured 20
years after it was first banded (LaVal and LaVal 1980). Humphrey et al.
(1977) provided the only neonatal mortality estimate, 8 percent, based
on one of two seasons of observation of one maternity colony. More
research on differences in survival rate among life stages is needed.

In summary, the information necessary to model extinction risk and guide
recovery of the Indiana bat is incomplete at this time. As referenced
above, sex-specific survival, age structure, and age-specific survival
data would vastly improve understanding of this species' demographics.
The primary approach to gathering such information for other taxa
requires capture-recapture methodologies that have not yet been applied
to this species. Recent advances in marking and molecular genetic
techniques, in combination with more powerful capture-recapture models,
may offer the opportunity to close critical information gaps.

[Chronology]{.underline}

Depending on local weather conditions, hibernation for Indiana bats
typically lasts from October through April (Hall 1962, LaVal and LaVal
1980), although it may be extended from September to May in northern
areas including New York, Vermont, and Michigan (Kurta et al. 1997,
Hicks 2004). The nonhibernation season, which includes spring emergence,
migration, reproductive activities, and fall swarming, varies depending
upon the sex (males may enter hibernation later than females) and the
location (northern latitudes may have shortened nonhibernation seasons)
(Figure 12). The following sections describe the annual life cycle for
the Indiana bat, beginning with the fall mating season.

[Fall Swarming and Mating]{.underline}

Indiana bats arrive at their hibernacula in preparation for mating and
hibernation as early as late July; usually adult males or
nonreproductive females make up most of the early arrivals (Brack 1983).
The number of Indiana bats active at hibernacula increases through
August and peaks in September and early October (Cope and Humphrey 1977,
Hawkins and Brack 2004, Rodrigue 2004, Hawkins et al. 2005). Males may
remain active through mid-October or later, especially at southern
sites. Upon arrival at a hibernaculum, Indiana bats \"swarm,\" a
behavior in which \"large numbers of bats fly in and out of cave
entrances from dusk to dawn, while relatively few roost in the caves
during the day\" (Cope and Humphrey 1977). Swarming continues for
several weeks, and during this time mating occurs, generally in the
latter part of the period. Adult females store sperm from autumn
copulations throughout winter, and fertilization is delayed until soon
after spring emergence from hibernation (Guthrie 1933). Limited mating
activity occurs throughout winter and in spring as bats leave
hibernation (Hall 1962).

Prior to hibernating, Indiana bats must store sufficient fat to support
metabolic processes until spring. During fall swarming, fat supplies for
Indiana bats are replenished as they forage in the vicinity of the
hibernaculum. Hall (1962) studied fall weight gain in Indiana bats
returning to Coach Cave in Edmonson County, Kentucky (which at the time
harbored a hibernating

![](media/image12.wmf){width="6.714583333333334in"
height="3.9659722222222222in"}

**Figure 12.** Indiana bat annual chronology.

population of approximately 100,000 Indiana bats). He documented that
bat weights were at the lowest point in the annual cycle when they
returned to the vicinity of the hibernaculum in late August and
September. Dissection revealed no stored fat in the bats at that time.
Weight, in the form of fat, was gained rapidly in September and bats
entering hibernation were at maximum weight. LaVal and LaVal (1980) also
evaluated seasonal changes in weight, based on weights of 3,290 male and
2,180 female Indiana bats in Missouri. At Pilot Knob Mine, the largest
of the Indiana bat hibernacula studied, the number of females active at
the cave peaked in late August. Females (on average) achieved maximum
weight in early October. Compared to females, peak activity of males was
later, and maximum weight gain was achieved in late October. A similar
pattern of pre-hibernation weight gain was observed in little brown bats
in the vicinity of a hibernaculum in Vermont (Kunz et al. 1998).

Male Indiana bats may make several stops at multiple hibernacula during
the fall swarming period and remain active over a longer period of time
at cave/mine entrances than do females (Cope and Humphrey 1977, LaVal
and LaVal 1980), most likely to mate with females as they arrive (Brack
et al. 2005c). Bats traveling between hibernacula during fall swarming
may also be assessing the relative suitability of potential hibernation
sites (Parsons et al. 2003). Nightly activity is correlated with
temperature; bats and their prey become constrained by falling
temperatures as autumn progresses. During swarming, most male bats roost
in trees during the day and fly to the cave or mine at night. At
Priority 3 hibernacula in eastern Kentucky, Kiser and Elliott (1996)
found male Indiana bats roosting primarily in dead trees on upper slopes
and ridgetops within 1.5 mi of the hibernaculum, and Gumbert (2001)
found an average of 1.2 mi between roost trees and the hibernaculum for
radio-tagged Indiana bats (mostly males). Two male Indiana bats in
Michigan roosted in trees 1.4 mi and 2.1 mi from their hibernaculum
(Priority 4) during fall swarming (Kurta 2000). Brack (2006) found a
range of 0.2 to 0.9 mi between roost trees, used by male and female
Indiana bats during fall swarming, and a Priority 3 hibernaculum in
Virginia, although he could not follow bats if they left the "project
area," so the range may have been greater.

Bat movement patterns in autumn often do not follow a simple linear
pattern of migration from summer habitat to the hibernacula. Parsons et
al. (2003) discussed the transitory nature of bats at this time of year,
noting that bats may travel relatively long distances from a swarming
site during the swarming season; they observed bats roosting up to 17 mi
from swarming sites and completing the round trip between the swarming
and roosting sites in one or two nights. Humphrey and Cope (1976)
documented several little brown bats making movements up to 37 mi (away
from the hibernaculum where they were captured during swarming). Indiana
bats have also been found making relatively long trips from hibernacula
during fall swarming.

Butchkoski (pers. comm., 2006) documented a radio-tagged male Indiana
bat in Pennsylvania making two trips between the hibernaculum where it
was captured to a site 9 mi away over a period of two weeks. Hawkins et
al. (2005) documented several Indiana bats radio-tagged at Wyandotte
Cave in Indiana traveling long distances from the cave during fall
swarming, including two females that were relocated over 19 mi from the
cave. Brack (2006) suggested that competition for foraging resources may
force bats to leave the immediate vicinity of the hibernacula to find
prime foraging habitat to replenish their energy reserves, particularly
at hibernacula that support large populations of Indiana bats and/or
multiple species.

Most swarming studies have been conducted at relatively small
hibernacula (see discussion of Priority 3 and 4 hibernacula above).
During the fall of 2003 and 2004, a radiotelemetry study of Indiana bats
during fall swarming was conducted at Wyandotte Cave, a P1 hibernaculum
in Indiana. Most radio-tagged bats were never relocated; four of 18 were
relocated in 2003 (Hawkins and Brack 2004) and 10 of 32 were relocated
in 2004 (Hawkins et al. 2005). All of the relocations occurred late in
the fall swarming season. Some Indiana bats were found to leave the
hibernaculum, traveling as far as 19 mi from the cave in a single night.
Most radio-tracking was done using ground tracking techniques, but these
long distance movements were documented using aerial tracking.
Researchers concluded that many of the radio-tagged bats that were not
relocated likely moved too far from the hibernaculum to be relocated
using the ground tracking techniques that were employed during most
tracking sessions. The long distances traveled by bats radio-tagged near
Wyandotte Cave, compared to smaller hibernacula, suggest that use of
habitat near hibernacula during swarming may differ between caves that
support large versus small populations of bats (Hawkins et al. 2005).
Wyandotte Cave, which currently supports a hibernating population of
over 50,000 Indiana bats, is part of a complex of hibernacula; within an
approximately 10 mi radius there are four Priority 1 hibernacula that
collectively support 128,000 Indiana bats. If all species of bats
hibernating in these caves are considered, the population may be near
one million bats (Hawkins and Brack 2004). Additional study is needed to
determine if fall swarming behaviors are affected by the size of a
hibernating population.

[Hibernation]{.underline}

Indiana bats tend to hibernate in the same cave or mine at which they
swarm (LaVal et al. 1976), although swarming has been observed at
hibernacula other than those in which the bats hibernated (Cope and
Humphrey 1977; J. MacGregor, Kentucky Department of Fish and Wildlife
Resources, pers. comm., 2005) and at caves that do not serve as
hibernacula for the species (V. Brack, Indiana State University, pers.
comm., 2006). It is generally accepted that Indiana bats, especially
females, are philopatric; that is, they return annually to the same
hibernacula (LaVal and LaVal 1980). However, exceptions have been noted
(Hall 1962, Myers 1964). Some Indiana bats apparently also move from
traditional hibernacula to occupy man-made hibernacula, primarily mines,
as these become available (see discussion in the Population Distribution
and Abundance section).

Most Indiana bats enter hibernation by the end of November (mid-October
in northern areas) (Kurta et al. 1997), although populations of
hibernating bats may increase throughout fall and into early January at
some hibernacula (Clawson et al. 1980). Indiana bats usually hibernate
in large, dense clusters ranging from 300 bats per square foot (LaVal
and LaVal 1980) to 484 bats per square foot (Clawson et al. 1980, Hicks
and Novak 2002), although cluster densities as high as 500 bats per
square foot have been recorded (Stihler 2005). While the Indiana bat
characteristically forms large clusters, small clusters and single bats
also occur (Hall 1962, Hicks and Novak 2002).

Indiana bats often winter in the same hibernaculum with other species of
bats and are occasionally observed clustered with or adjacent to other
species, including gray bats, Virginia big-eared bats, little brown
bats, and northern long-eared bats (Myers 1964, LaVal and LaVal 1980,
Kurta and Teramino 1994). Additional habitat-specific information on
Indiana bat hibernacula is found in the Hibernation Habitat section.

During hibernation, Indiana bats arouse naturally, as do all hibernating
mammals (Thomas et al. 1990). Several researchers have observed that
Indiana bats arouse during hibernation (Hall 1962, Myers 1964, Hardin
and Hassell 1970, Henshaw 1970). Hicks and Novak (2002) noted that, in
an Indiana bat hibernaculum in New York, there were long periods of
little or no bat movement, with occasional bouts of activity. Generally,
a rhythm of approximately one arousal every 12 to 15 days for
hibernating bats is considered typical, but considerable variation has
been observed (Speakman and Thomas 2003). Hardin and Hassell (1970)
observed that the average time between movements of tagged Indiana bats
during hibernation was 13.1 days, but noted that some movements may not
have been detected. Further, some bats may arouse and not move;
therefore, movement may not be a reliable indicator of arousal (Dunbar
and Tomasi, in press).

The frequency of arousal varies during the hibernation period. During
the later stage of hibernation (i.e., spring), bats arouse more often
and may move towards the entrance of the cave. In Barton Hill mine (New
York) in early April, Indiana bat clusters shifted roost sites as the
bats moved toward a "staging area" near the entrance; numbers within
clusters also became more variable (A. Hicks, New York State Department
of Environmental Conservation, pers. comm., 2002). Clawson et al. (1980)
observed Indiana bats responding to cave wall temperatures in a study of
five hibernacula in Missouri. Indiana bats roosted in deeper cave
passages in the fall, moved to colder roosts (primary roosting areas) in
mid-winter as the rock temperatures declined, and returned to warmer
roost sites in the spring before emerging. Human disturbance can
increase the frequency of arousal in hibernating bats. Microclimate
factors in hibernacula can also influence the frequency of arousal (see
discussion in the Hibernacula Microlimate section).

[Spring Emergence]{.underline}

The timing of annual spring emergence of Indiana bats from their
hibernacula may vary across the range, depending on latitude and weather
(Hall 1962). Based on trapping conducted at the entrances of caves in
Indiana and Kentucky, Cope and Humphrey (1977) observed that peak spring
emergence of female Indiana bats was in mid-April, while most males were
still hibernating. The proportion of females active at the entrance of
hibernacula decreased through April, and by early May none remained.
Peak emergence of males occurred in early May, and few were left
hibernating by mid-May. LaVal and LaVal (1980) made similar observations
at Missouri hibernacula; females started emerging in late March to early
April, and outnumbered males active at hibernacula entrance during that
period. By the end of April, few females remained, and males dominated
the sample of bats captured at hibernacula entrances. At the Mt. Hope
mine complex in New Jersey, peak spring emergence of females was in
early April, and emergence of males peaked at the end of April (Scherer
2000). Exit counts from several hibernacula in southern Pennsylvania and
Big Springs Cave in Tucker County, West Virginia, suggest that peak
emergence is mid-April for these two areas (Butchkoski and Hassinger
2002, Rodrigue 2004). Spring surveys of the interior of Barton Hill mine
in New York documented substantial numbers of Indiana bats through April
and into mid-May; however, by the end of May, only one-tenth of the
population remained (A. Hicks, pers. comm*.*, 2005).

In spring when fat reserves and food supplies are low, migration
provides an additional stress and, consequently, mortality may be higher
immediately following emergence (Tuttle and Stevenson 1977). This
increased risk of mortality may be one reason why many males do not
migrate far from the hibernacula (Brack 1983, Gardner and Cook 2002,
Whitaker and Brack 2002). Movements of 2.5-10 miles by radio-tagged male
Indiana bats were reported in Kentucky, Missouri, and Virginia (Hobson
and Holland 1995, Rommé et al. 2002). However, other males leave the
area entirely upon emergence and have been captured throughout various
summer habitats (Kurta and Rice 2002, Whitaker and Brack 2002).

Female Indiana bats may leave immediately for summer habitat or linger
for a few days near the hibernaculum. Once en route to their summer
destination, females move quickly across the landscape. One female
released in southeastern New York moved 35 miles in about 85 minutes
(Sanders et al. 2001). Radiotelemetry studies in New York documented
females flying between 10 and 30 miles in one night after release from
their hibernaculum, arriving at their maternity sites within one night
(Sanders et al. 2001; Hicks 2004) One radiotagged female bat released
from Canoe Creek Mine in Pennsylvania traveled approximately 60 miles in
one evening (Butchkoski, pers. comm., 2005). A female Indiana bat from a
hibernaculum in Luzerne County, Pennsylvania, traveled 56 miles to her
summer habitat in Berks County, Pennsylvania, in two nights (Butchkoski
and Turner 2006).

Indiana bats can migrate hundreds of miles from their hibernacula.
Twelve female Indiana bats from maternity colonies in Michigan migrated
an average of 296 miles to their hibernacula in Indiana and Kentucky,
with a maximum migration of 357 miles (Winhold and Kurta 2006). Gardner
and Cook (2002) also reported on long-distance migrations for Indiana
bats traveling between their summer ranges and hibernacula. Shorter
migration distances are also known to occur. Indiana bats banded (during
summer) at multiple locations in Indiana have been found in hibernacula
only 34 to 50 miles from their summer range (L. Pruitt, Service, pers.
comm., 2006). Some banded female Indiana bats from maternity colonies in
Mammoth Cave National Park have been found hibernating in nearby caves
(J. MacGregor, pers. comm., 2006). Recent radiotelemetry studies of 70
spring emerging Indiana bats (primarily females) from three New York
hibernacula found that most of these bats migrated less than 40 miles to
their summer habitat (A. Hicks, pers. comm., 2005; S. von Oettingen,
Service, unpublished data, 2005).

Little information is available to determine habitat use and needs for
Indiana bats during migration. Recent spring emergence telemetry studies
in New York and Pennsylvania are beginning to document migratory routes
in the northeast (A. Hicks, pers. comm., 2005; C. Butchkoski, pers.
comm., 2005; J. Chenger, pers. comm., 2005).

[Summer Life History and Behavior]{.underline}

Reproductive females arrive at their summer habitats as early as
mid-April in Illinois, New York, and Vermont (Gardner et al. 1991a,
Britzke 2003, Hicks 2004). Humphrey et al. (1977) reported that Indiana
bats first appeared at their maternity roost sites in early May in
Indiana, with substantial numbers arriving in mid-May. However, Whitaker
et al. (2005b) counted 25 bats emerging from a primary Indiana bat
maternity roost tree (used in previous years) in central Indiana on
April 9, and smaller numbers of bats have been observed emerging from
known Indiana bat roosts on this study area as early as late March
(Whitaker et al. 2005a). Indiana bats from hibernacula in southern
Indiana and Kentucky enter southern Michigan as early as late April,
although most do not arrive until the middle or end of May (Kurta and
Rice 2002). Most Indiana bats from hibernacula in New York fly directly
to their summer range in Vermont and southeastern New York beginning in
mid-April (Britzke 2003, Hicks 2003).

Less is known about male migration patterns. Some males summer near
their hibernacula (Whitaker and Brack 2002). Some males disperse
throughout the range and roost individually or in small numbers in the
same types of trees (although males often use smaller trees and are more
likely to roost in live trees; see discussion in the Summer Habitat
section) and in the same areas as females (Kurta and Rice 2002).

Non-reproductive females may also roost individually or in small
numbers, including in the same trees as reproductive females (A. Kurta,
Eastern Michigan University, pers. comm., 2005). Relatively little is
known about the summer habits of males and non-reproductive females;
therefore, the following section is primarily focused on summer life
history of reproductive females.

[Maternity Colony Formation]{.underline}

After arriving at their summer range, female Indiana bats form maternity
colonies. Indiana bat maternity colonies can vary greatly in size. It is
difficult to enumerate colony size because colony members are dispersed
among various roosts at any given time (Kurta 2005). Most estimates of
colony size are based on counts of bats emerging from known Indiana bat
maternity roosts. Estimating colony size based on emergence counts
requires the researcher to make assumptions. First, based on the date of
the counts, researchers generally assume that emerging bats are adult
female Indiana bats (if counts occur prior to dates when young typically
become volant), or that young-of-the-year bats are included in the
count. There are documented cases of adult male bats in maternity
roosts, but it is considered unlikely that large numbers of male bats
occupy maternity roosts. Second, the assumption is made that all bats
emerging from the roost are Indiana bats, although this assumption is
generally not tested. There are documented cases of more than one
species of bats using the same maternity roost, either simultaneously,
or within the same season. Third, assumptions must be made regarding
what proportion of the colony may have been counted during emergence
counts. Counts based on multiple nights at multiple known roost sites
over the course of the maternity season provide better estimates than a
single count at a single tree. However, even a single count at a primary
maternity roost tree provides an estimate of minimum colony size.

Although most documented maternity colonies contained 100 or fewer adult
females (Harvey 2002), as many as 384 bats have been reported emerging
from one maternity roost tree in Indiana (Whitaker and Brack 2002).
Whitaker and Brack (2002) indicated that average maternity colony size
in Indiana was approximately 80 adult female bats. The mean maximum
emergence count after young began to fly (measured in 12 studies) was
approximately 119 bats (Kurta 2005), suggesting that 60 to 70 adult
females were present (assuming that most adult females successfully
raise one pup to volancy).

Barclay and Kurta (in press) suggested five potential explanations for
the establishment of maternity colonies in cavity- and bark-roosting
bats:

1)  High-quality roosts may be limiting in some areas,

2)  Foraging efficiency - members of a colony communicate regarding good
    foraging areas,

3)  Reduced predation risk,

4)  Thermoregulatory advantages - roosting in a large group may be a
    mechanism for reproductive females to reduce thermoregulatory costs
    by clustering, and

5)  Water conservation by reducing evaporative water loss (However, see
    Kerth et al. 2001 for a discussion of why foraging efficiency is
    unlikely to explain coloniality in species of bats in which members
    of the colony do not forage together).

The relative importance of these benefits of coloniality is not known,
but the thermoregulatory advantages of colonial roosting have been
clearly demonstrated. Female bats in late pregnancy and their pups are
poor thermoregulators (Speakman and Thomas 2003), and prenatal and
postnatal growth are controlled by the rate of metabolism and body
temperature (Racey 1982). Humphrey et al. (1977) demonstrated the
importance of roost temperature in the growth and development of young
Indiana bats. Barclay and Kurta (in press) concluded that "the weight of
evidence suggests that roost microclimate and its impact on
thermoregulation are the primary factors involved in roost selection by
forest-dwelling bats," although experimental tests of this hypothesis
are lacking. In addition to selecting favorable roost sites, clustering
(in maternity roosts) is another mechanism used by bats to maintain
roost temperatures favorable for prenatal and postnatal development.
Thus, colonial roosting is likely a life history strategy adopted by
Indiana bats (like many other temperate-zone bats) to improve
reproductive success (Barclay and Harder 2003).

[Maternity Roosts]{.underline}

Indiana bat maternity roosts can be described as primary or alternate
based upon the proportion of bats in a colony consistently occupying the
roost site (Kurta et al. 1996, Callahan et al. 1997, Kurta et al. 2002).
In Missouri, Callahan (1993) defined primary roost trees as those with
exit counts of more than 30 bats on more than one occasion; however,
this number may not be applicable to small-to-moderate sized maternity
colonies (Kurta et al. 1996). For smaller maternity colonies,
determining the number of "bat days" over one maternity season (one bat
day being one bat using a tree for one day) may be a better technique
for distinguishing primary from alternate roosts (Kurta et al. 1996).

Maternity colonies typically use 10 to 20 trees each year, but only one
to three of these are primary roosts used by the majority of bats for
some or all of the summer (Callahan 1993, Callahan et al. 1997). After
the young are capable of flight (volant), the composition of a colony at
a primary roost is fluid, as individual bats leave and return (Barclay
and Kurta, in press). Kurta et al. (2002) observed that certain roost
trees were occupied by a "quasi-stable number of Indiana bats for days
or weeks" at a time. However, during this time, individuals (based on
radiotelemetry observations) consistently moved into and out of the
trees.

Alternate roosts are used by individuals or a small number of bats and
may be used intermittently throughout the summer or used on only one or
a few days. All roost trees eventually become unusable - by losing bark,
falling over, or through competition with other animals - and these
events can often occur suddenly and without warning (Gardner et al.
1991a, Kurta and Foster 1995, Belwood 2002). The use of alternate roosts
may be a way of discovering new primary roosts since Indiana bats must
maintain an awareness of suitable replacements in case of an emergency
(Kurta et al. 1996, 2002). Thus, "primary" roosts are a function of bat
behavior (aggregation) and roost physical characteristics (e.g., large
size). Studies documenting roost trees used by individuals in a colony
identified a range in the number of alternate roosts. For example, based
on Callahan's (1993) definition, Watrous (unpublished data, 2005)
documented 12, 9 and 14 alternate roost trees for three colonies in the
Lake Champlain Valley of Vermont and New York.

Indiana bats appear to have a fission-fusion society as demonstrated by
frequent roost changing (Kurta et al. 2002, Kurta 2005). Barclay and
Kurta (in press) explain "that in this type of a society, members
frequently coalesce to form a group (fusion), but composition of that
group is in perpetual flux, with individuals frequently departing to be
solitary or to form smaller groups (fission) for a variable time before
returning to the main unit." It may be possible that some bats select
individuals with whom to roost and avoid roosting with others (Barclay
and Kurta, in press). Although many members of a colony may reside in
one tree at any one time, other members roost elsewhere as solitary
individuals or in small subgroups of fluctuating composition. Such a
fission-fusion society has been suggested for other species of forest
bats, as well (Kerth and König 1999, O'Donnell 2000, Kurta et al. 2002,
Willis and Brigham 2004).

On average, Indiana bats switch roosts every two to three days, although
reproductive condition of the female, roost type, and time of year
affect switching (Kurta et al. 2002, Kurta 2005). Lactating females may
change roosts less often than pregnant or post-lactating females. Bats
roosting under exfoliating bark may change more often than bats roosting
in crevices (Kurta et al. 1996, 2002; Gumbert et al. 2002; Carter 2003;
Kurta 2005). Roost switching occurs less often in the spring, most
likely due to colder night temperatures that may induce extended torpor
(Gumbert et al. 2002, Britzke et al. 2006).

[Night Roosts]{.underline}

Indiana bats use night roosts (Butchkoski and Hassinger 2002, Kiser et
al. 2002, Ormsbee et al., in press), although there is limited research
on where and why they night roost. Adults of both sexes as well as
juveniles use night roosts (Kiser et al. 2002). Indiana bats may night
roost for a variety of reasons, including (but not limited to) resting,
aiding in digestion, protection from inclement weather, and conservation
of energy (Ormsbee et al., in press). Night roosting may occur at the
bat's day roost in conjunction with nocturnal tending of its young or
during inclement weather, or, more often, at sites not generally used as
day roosts (Ormsbee et al., in press). Indiana bats night roost in trees
(Butchkoski and Hassinger 2002, Murray and Kurta 2004), bridges (Mumford
and Whitaker 1982, Kiser et al. 2002), caves (Gumbert et al. 2002), and
bat houses (Butchkoski and Hassinger 2002). We also have documentation
that Indiana bats may night roost in abandoned underground mine portals
from captures of bats entering portals during the night (P. Measel,
pers. comm., 2005).

[Reproduction]{.underline}

Females give birth to a single young in June or early July (Easterla and
Watkins 1969, Humphrey et al. 1977, Kurta and Rice 2002) while in their
maternity roosts. As previously discussed, maternity colonies reduce
thermoregulatory costs, which, in turn, increases the energy available
for birthing and raising young (Barclay and Harder 2003). There are no
documented occurrences in which a female Indiana bat has successfully
given birth and raised a pup alone without communal benefits of a
maternity colony. A study by Belwood (2002) shows asynchronous births
extending over two weeks within one colony. This asynchrony results in
great variation in size of juveniles (newborn to almost adult size
young) in the same colony.

In Indiana, lactating females have been recorded from June 10 to July 29
(Whitaker and Brack 2002). Lactation begins at birth and continues
through early volancy of young. Young Indiana bats are volant within 3-5
weeks of birth (Mumford and Cope 1958, Easterla and Watkins 1969, Cope
et al. 1974, Humphrey et al. 1977, Clark et al. 1987, Gardner et al.
1991a, Kurta and Rice 2002, Whitaker and Brack 2002). Young born in
early June may fly as early as the first week of July (Clark et al.
1987), with others flying from mid-to-late July. Once young Indiana bats
are volant, the maternity colony begins to disperse. The use of primary
maternity roosts also diminishes, although the bats may stay in the
maternity roost area until migrating to their respective hibernacula.
The bats become less gregarious and the colony uses more alternate
roosts (Kurta et al. 1996), possibly because there is no longer the need
for the adult females to cluster for thermoregulation and to nurture
their young. However, at least 69 bats were observed exiting a primary
roost tree in central Indiana in late September (D. Sparks, pers. comm.,
2006).

Although the preceding discussion provides a seasonal framework for
Indiana bat reproduction, the timing of reproductive events is somewhat
weather-dependent (Grindal et al. 1992, Lewis 1993, Racey and Entwistle
2003). Adverse weather, such as cold spells, increases energetic costs
for thermoregulation and decreases availability of insect prey (i.e.,
the available energy supply). Bats may respond to a negative energy
balance by using daily torpor, and some females may not bear a pup in
years with adverse weather conditions (Barclay et al. 2004). In females
that maintain pregnancy, low body temperatures associated with daily
torpor slow chemical reactions associated with fetal and juvenile growth
and milk production and may cause annual and individual variation in the
time when young are born and how quickly young develop.

[Site Fidelity]{.underline}

Research indicates that Indiana bats exhibit site fidelity to their
traditional summer maternity areas. Numerous studies have documented
female Indiana bats annually returning to the same home range to
establish maternity colonies (Humphrey et al. 1977; Gardner et al.
1991a, 1991b; Gardner et al. 1996; Callahan et al. 1997; Whitaker and
Sparks 2003; Whitaker et al. 2004). While use of new roosts that become
available within established home ranges has been documented, pioneering
of new maternity colonies has not been documented. We presume that the
species is capable of forming new maternity colonies, but neither the
mechanism nor circumstances under which the Indiana bat pioneers
maternity colonies has been documented.

Roost trees, although ephemeral in nature, may be occupied by a colony
for a number of years until they are no longer available or suitable.
Roost tree reoccupation of 2 to 6 years has been documented in a number
of studies (Gardner et al. 1991b; Whitaker et al. 2004; Barclay and
Kurta, in press; K. Watrous, pers. comm., 2005).

Maternity colonies of Indiana bats also appear to be faithful to their
foraging areas within and between years (Cope et al. 1974; Humphrey et
al. 1977; Gardner et al. 1991a, 1991b; Murray and Kurta 2004; Sparks et
al. 2005b). Available data also suggest that individual Indiana bats are
faithful to their foraging areas between years. Gardner et al. (1991a,
1991b) observed that individual females returned to the same foraging
areas year after year, irrespective of whether they were captured as
juveniles and recaptured and tracked as adults or captured as adults and
then followed. In Indiana, one female Indiana bat was radiotracked in
two different years and both roosting and foraging habits were found to
be remarkably consistent between years (Sparks et al. 2005b). In
Michigan, Murray and Kurta (2002, 2004) recaptured 41 percent (12 of 29)
of banded females when mist netting at the same area in subsequent
years. Further studies of this colony reported use of a wooded fenceline
as a commuting corridor for at least nine years (Kurta 2005, Winhold et
al. 2005).

[Fall Migration]{.underline}

Maternity colonies begin disbanding during the first two weeks in
August, although some large colonies may maintain a steadily declining
number of bats into mid-September (Humphrey et al. 1977, Kurta et al.
1993b). It should be noted that, in some cases, bats emerging from
documented Indiana bat roosts later in the season were determined to be
another species (A. Hicks, pers. comm., 2005). Even in northern areas,
such as Michigan, a few Indiana bats may remain into late September and
early October; these late migrants may be young-of-the-year (Kurta and
Rice 2002). Members of a maternity colony do not necessarily hibernate
in the same hibernacula, and may migrate to hibernacula that are over
300 km (190 mi) apart (Kurta and Murray 2002, Winhold and Kurta 2006).

[Food Habits]{.underline}

Indiana bats feed on flying insects, with only a very small amount of
spiders (presumably ballooning individuals) included in the diet. Four
orders of insects contribute most to the diet: Coleoptera, Diptera,
Lepidoptera, and Trichoptera (Belwood 1979, Brack 1983, Brack and LaVal
1985, Lee 1993, Kiser and Elliot 1996, Kurta and Whitaker 1998, Murray
and Kurta 2002, Whitaker 2004). Various reports differ considerably in
which of these insect orders is most important. Terrestrial-based prey
(moths and beetles) were more common in southern studies, whereas
aquatic-based insects (flies and caddisflies) dominated in the north.
Presumably, this difference indicates that southern bats foraged more in
upland habitats, and northern bats hunted more in wetlands or above
streams and ponds. These differences in diet are consistent with
observations of foraging animals in various studies. However, apparent
geographic differences are confounded by differences in survey
techniques, in sex or age of animals studied, in availability and use of
habitats, and in composition of the local bat community (i.e., presence
of potential competitors) (Murray and Kurta 2002, Brack, in press).

Hymenopterans (winged ants) also are abundant in the diet of Indiana
bats for brief, unpredictable periods corresponding with the sudden
occurrence of mating swarms. Although not as dramatic, seasonal
occurrence of Asiatic oak weevils in the diet indicates use of an
abundant resource available only for a limited part of the season (Brack
1983, Brack and Whitaker 2004). Consistent use of moths, flies, beetles,
and caddisflies throughout the year at various colonies suggests that
Indiana bats are selective predators to a certain degree, but
incorporation of ants into the diet also indicates that these bats can
be opportunistic (Murray and Kurta 2002). Hence, Brack and LaVal (1985)
and Murray and Kurta (2002) suggested that the Indiana bat may best be
described as a "selective opportunist," as are a number of other
*Myotis* species (Fenton and Morris 1976).

At individual colonies, dietary differences exist between years, within
years by week, between pregnancy and lactation, and within nights
(Murray and Kurta 2002). Although some authors ascribe various
adaptationist reasons for these differences, it is difficult to explain
why different studies are not consistent in their results. For example,
Belwood (1979) reported an increase in moth consumption during
lactation, but Kurta and Whitaker (1998) reported a decrease. Kurta and
Whitaker (1998) stated that caddisfly consumption remained constant
throughout the season, whereas Brack (1983) reported a decrease. Murray
and Kurta (2002) found a significant increase in moth consumption by one
colony during lactation in one year but not in the following year. These
inconsistencies within and among studies suggest that Indiana bat diets,
to a large degree, may reflect availability of preferred types of
insects within the foraging areas that bats happen to be using, again
suggesting that they are selective opportunists (Murray and Kurta 2002).

[Foraging Behavior]{.underline}

The Indiana bat is a nocturnal insectivore. It emerges shortly after
sunset and begins feeding on a variety of insects that are captured and
consumed while flying (Sparks et al. 2005b). At two maternity colonies -
one in Michigan and one in Illinois - Indiana bats began emerging from
the roost to forage around 19 minutes after sunset, with peak emergence
around 21 to 26 minutes after sunset (Viele et al. 2002). In western
Illinois, emergence averaged 21 minutes after sunset and peaked 30 to 45
minutes after sunset (Gardner et al.1991b). There may be considerable
variation in emergence times within a colony that is not related to
light level, ambient temperature, or number of bats residing in the
colony (Gardner et al. 1991a, Viele et al. 2002). Emergence occurs later
in relation to sunset near the summer solstice and closer to sunset in
spring and late summer (Viele et al. 2002). In Indiana, bats emerged
38-71 minutes after sunset throughout the season, but emergence was
earlier when young became volant (i.e., the time of exit was inversely
related to the number of bats exiting the roost) (Brack 1983). After
juveniles become volant, they typically leave the roost for foraging
after adults have departed (Kurta et al. 1993b). In Virginia, nightly
activity started earlier in the evening in relation to sunset as autumn
progressed (Brack 2006).

Thirteen foraging areas were identified that were used by pregnant and
lactating Indiana bats in southern Michigan: five were used only by
pregnant bats, four were used only by lactating bats, and four were used
by both pregnant and lactating bats (Murray 1999, Murray and Kurta
2004). Individual females visited one to four foraging areas each night.
When two or three bats were radiotracked simultaneously, they seldom
used the same foraging area and were found in different areas over 5 km
(3 mi) apart.

Indiana bats usually forage and fly within an air space from 6 to 100 ft
above ground level (Humphrey et al. 1977). Most Indiana bats caught in
mist nets are captured over streams and other flyways at heights greater
than 6 ft (Brack 1983, Gardner et al. 1989). In autumn, observations of
light-tagged bats suggest that Indiana bats do not typically fly close
to the ground or water (Brack 1983).

Linear distances between roosts and foraging areas for females range
from 0.3 to

5.2 miles, although most distances were less than half the maximum
distance (Murray and Kurta 2004, Sparks et al. 2005b). For example, one
individual at a colony in Indiana moved 5.2 miles between roosts and
foraging area; however, the mean distance of 41 bats from the same
colony was 1.9 miles. In Canoe Creek, Pennsylvania, an area with
significant changes in elevation, reported distances between roost and
foraging areas ranged from 1.5 to 2.8 miles with an average distance of
2.1 miles (Butchkoski and Hassinger 2002). Murray and Kurta (2004) and
Sparks et al. (2005b) speculate that the variations in distances to
foraging areas were due to differences in habitat type, inter-specific
competition, and landscape terrain.

[Home Range]{.underline}

Indiana bats occupy distinct home ranges, particularly in the summer
(Garner and Gardner 1992). However, relatively few studies have
determined the home ranges of Indiana bats, and these studies based
their calculations on a small number of individuals. Further, direct
comparison of the home range estimates between studies is difficult due
to different methodologies used in collecting the data, inconsistency in
terminology, and different methods of calculating home range size (Lacki
et al. 2006). Home range size varies between seasons, sexes, and
reproductive status of the females (Lacki et al. 2006). Standardized
methodology and terminology and additional research will be necessary to
further refine home range estimates.

Kiser and Elliot (1996) identified minimum foraging areas for 15 Indiana
bats (14 males, 1 female) at a hibernaculum in Kentucky. Their estimates
ranged from about 69 to 734 acres (excluding the cave in the estimate),
with a mean of 385 ± 249 acres. Rommé et al. (2002) calculated a mean
home range near a hibernaculum in Missouri of 1,648 ± 2456 acres for
spring and fall (based on pooled data for nine bats--male and female)
and 3,825 ± 3,518 acres for fall home range (based on three males). In
Virginia, Brack (2006) calculated average active areas for three females
and eight males near a hibernaculum as 618 ± 247 acres (n=11) using mean
convex polygons and 892 ± 640 acres (n=10) using adaptive kerneling
(core areas). Menzel et al. (2005) tracked seven female and four male
Indiana bats from May to August in Illinois. No significant differences
in home ranges between males and females were observed and home range
estimates were subsequently grouped. Menzel et al. (2005) determined the
mean summer home range size of the 11 Indiana bats to be 357 acres.
Watrous (in press) calculated a mean home range of 205 acres for 14
female Indiana bats in Vermont.

**Hibernation Habitat**

During winter, Indiana bats are restricted to suitable underground
hibernacula. The majority of these sites are caves located in karst
areas of the east-central United States; however, Indiana bats also
hibernate in other cave-like locations, including abandoned mines in
several states, a railroad tunnel in Pennsylvania, and even a
hydroelectric dam in Michigan. Hall (1962) observed that Indiana bats
find and occupy newly available hibernating sites very quickly. In some
areas, such as Illinois and New York, the largest and most rapidly
growing populations occur in abandoned mines (Hicks and Novak 2002, Kath
2002). Indiana bats occupied Pilot Knob Mine in Missouri after mining
ceased in the 1890s; by the 1950s, Pilot Knob Mine held the largest
population of Indiana bats in Missouri (\>100,000 bats) and still has
the largest population in the state (Hall 1962, Myers 1964, Clawson
2002). Rapid population growth has also occurred at caves where measures
have been implemented to restore hibernacula in cases where previous
alterations and/or disturbance made the cave unsuitable or marginally
suitable for hibernation. For example, the population at Wyandotte Cave
in Indiana grew from a low of 500 bats in 1955 to a current population
of over 50,000 bats in response to restoration efforts and measures to
eliminate disturbance of hibernating bats. At Saltpetre Cave in
Kentucky, the population grew from 475 in 1999 to over 6,000 in 2005 in
response to measures that were implemented to restore the microclimate
and protect hibernating bats from disturbance. Only a small percentage
of caves (and mines) within the range of the Indiana bat provide the
conditions required for successful hibernation (Service 1983); for
recovery, it is essential to conserve and manage those sites with
suitable microclimate, and to restore suitable microclimate to sites
that have been altered.

[Hibernacula Microclimate]{.underline}

*Ambient Temperature during Torpor*

Most Indiana bats hibernate in caves or mines where the ambient
temperature remains below 10°C (50.0°F) but infrequently drops below
freezing (Hall 1962, Myers 1964, Henshaw 1965, Humphrey 1978), and the
temperature is relatively stable (Tuttle and Kennedy 2002). Tuttle and
Kennedy (2002) compared mid-winter temperatures at major hibernacula and
reported that populations hibernating where temperatures were between 3°
and 7.2°C (37.4° and 45°F) remained stable or increased, while
populations hibernating at temperatures above or below this range were
unstable or had declined. However, Brack et al. (2005a) reported that
hibernacula temperatures below 5°C (41.0°F) are too cold because they
observed that in hibernacula in Indiana the highest concentrations of
Indiana bats were found at sites with mid-winter temperatures of 6° to
7°C (42.8° to 44.6°F).

Researchers studying hibernacula temperature have used different
temperature monitoring instruments and techniques, making it difficult
to compare results of studies. For example, among long-term (\>2 years)
datasets, Henshaw (1965) left thermometers inside hibernacula and
measured maximum and minimum temperatures once every two weeks; Brack
and his colleagues usually measured temperatures near hibernating
clusters of Indiana bats during occasional cave visits (e.g**.,** Brack
et al. 1984, Brack et al. 2003, Whitaker et al. 2003); and Tuttle and
Kennedy (2002) took near-continuous temperature readings using data
loggers left inside hibernacula. Standard (and thus comparable)
protocols for quantifying the thermal profiles of hibernacula used by
Indiana bats over ecologically meaningful periods (e.g., \>5 years) have
not been established, but continuous monitoring using data loggers is
currently the most useful approach. Any protocol for monitoring with
data loggers should be designed to maximize the likelihood that
temperature measurements are taken in all areas of a hibernaculum used
by bats during winter. Ideally, temperature measurements from data
loggers would be temporally correlated to remotely-sensed information
(e.g., images from infrared cameras) on the actual whereabouts of
individuals or colonies within the hibernaculum. The second factor
complicating the analysis of temperature data gathered by different
researchers, that work in different geographic areas, is the
relationship between temperature and the degree of gregariousness
exhibited by Indiana bats.

Several researchers have noted an inverse relationship between ambient
roost temperature and the size of hibernating clusters formed by Indiana
bats (i.e., larger clusters are typically found at colder sites, whereas
smaller clusters are found in warmer sites) (Clawson et al. 1980, Brack
et al. 1984). Thus, studies that focus on characterizing temperatures of
hibernacula with large, dense colonies of hibernating bats (e.g., P1
caves; Tuttle and Kennedy 2002) may be biased toward colder temperatures
and studies of sites with relatively smaller numbers and dispersed
clusters of Indiana bats may be biased toward warmer temperatures.
Behavioral thermoregulation, in the form of clustering, likely allows
Indiana bats to hibernate at a wider range of ambient temperatures than
would be possible for non-colonial species, but the effect of clustering
density is difficult to measure.

Discussion about the "optimum" range of temperatures for hibernation by
Indiana bats relies heavily on temperature data collected inside
hibernacula where large numbers are known (or in some cases were known)
to hibernate. Such data are correlative and should be treated
cautiously. For example, certain hibernating populations may be using
available, rather than optimal, habitat. The assumption that the largest
colonies aggregate in the most optimal conditions is likely an
oversimplification (Henshaw 1970). Furthermore, intra-specific
differences in thermal physiology between geographic regions have been
observed in vespertilionid bats during warmer months (Willis et al.
2005) and such differences may persist into the winter. Without a
clearer picture of the factors influencing the energy and water balance
of Indiana bats under different microclimate conditions, the precise
range of optimal hibernacula conditions will remain equivocal.

There are few quantitative data pertaining to energy use by Indiana bats
during hibernation. In laboratory experiments, Henshaw (1965) measured
energy expenditure by Indiana bats as a function of ambient
temperature*.* During torpor, Indiana bats consumed the least amount of
energy at 5ºC, with energy use increasing at temperatures of both -5ºC
and 10ºC (23.0ºF and 50.0ºF). However, Henshaw (1965) did not quantify
energy expenditure by Indiana bats at intermediate temperatures (i.e.,
1º to 4ºC and 6º to 9ºC (33.8º to 39.2ºF and 42.8º to 48.2ºF)). T.
Tomasi (unpublished data, 2006) collected metabolic data for Indiana
bats hibernating in a laboratory at 1^o^, 3^o^, 5^o^, 7^o^, and 9^o^C
(33.8º, 37.4º, 41.0º, 44.6º, 48.2ºF) and his preliminary analysis showed
a significant effect of temperature on the metabolic rate of individual
bats (n=13). Lowest metabolic rates were measured for bats in the 5^o^C
(41.0ºF) treatment. V. Brack (pers. comm., 2004; Brack 2005) raised
concerns regarding laboratory experiments that measure the efficiency of
hibernation at various temperatures without considering the energetic
costs and frequency of arousals. He suggested that the energy savings of
torpor at a low versus high ambient temperature (e.g., 3ºC versus 8ºC
(37.4ºF versus 46.4ºF)) may be outweighed by the increased cost of
arousal, the increased cost of maintenance of normothermic body
temperatures during arousal, and the secondary effects of metabolic
inhibition (e.g., oxidative stress, reduced immunocompetence; Geiser
2004). Patterns of energy use by hibernating Indiana bats over a range
of ambient temperatures could be quantified in the laboratory (including
the cost of arousal and maintenance of normothermic body temperatures
during arousal). Tomasi (pers. comm., 2006) proposes to collect
additional data to evaluate the energetic cost of arousal at various
temperatures (to be analyzed in conjunction with data on the metabolic
rates of Indiana bats hibernating at those temperatures). Further study
is also needed to better understand how clustering affects heat loss and
re-warming of hibernating Indiana bats. Decreased thermal conductance
(Kurta 1985) and increased radiant heat gain experienced by bats in a
cluster (Geiser and Drury 2003) may significantly decrease their energy
expenditure during arousal from low ambient temperatures.

*Water Balance and Winter Activity of Hibernating Bats*

Little is known about the water balance of hibernating Indiana bats*.*
Henshaw (1965, 1970) measured evaporative water loss by Indiana bats and
noted that, as with other species, water loss was a function of the
vapor pressure deficit of ambient air; bats lost more water as the
humidity of air decreased. Although Indiana bats apparently experience
less evaporative water loss during hibernation than little brown bats
(Henshaw 1970, Brenner 1973), extensive laboratory research on the
latter species offers insight into the importance of air moisture on
hibernation by species of *Myotis.* Thomas and Cloutier (1992) observed
that at relative humidity levels below 99.3 percent (air temperature 2º
to 4ºC), evaporative water loss rates of little brown bats exceeded
metabolic water production under laboratory conditions. The implication
of this research is that the lower the humidity in a hibernaculum, the
more frequently a bat hibernating at that site will need to arouse and
replenish water supplies.

Researchers have suggested that the need for water is a major factor
influencing the arousal frequency of hibernating bats (Speakman and
Racey 1989, Thomas and Geiser 1997, Speakman and Thomas 2003), and
Indiana bats have been observed drinking during arousals (Hall 1962,
Myers 1964). Considering that arousals account for approximately 75 to
85 percent of winter fat depletion (Thomas 1995, Speakman and Thomas
2003), humidity of the hibernacula could play a major role in both the
water and energy balance of hibernating bats. Although quantitative
field studies are limited, several early researchers noted that Indiana
bats arouse frequently during hibernation (Hall 1962, Myers 1964, Hardin
and Hassell 1970, Henshaw 1970). It is possible that arousal frequency
in Indiana bats, and thus energy use and probability of survival, is
partially a function of the humidity of the hibernacula. Laboratory
measurements of arousal frequency as a function of water vapor pressure
deficit in Indiana bats have not been made. Temperature may also play a
role in the arousal frequency of hibernating Indiana bats, but targeted
studies are lacking. Hicks and Novak (2002) observed infrequent arousals
between late January and mid-May at a cold (-1.1°C to 3.3°C) (30.0° to
37.9°F) hibernaculum occupied by 700 to 1000 Indiana bats, but similar
data from warmer sites or larger colonies are not available.

Henshaw (1965) reported air movement in most of the Indiana bat and
little brown bat hibernacula that he studied. Although air circulation
can have a dramatic influence on energy expenditure (through convective
heat loss) and water balance (through transdermal water loss; Bakken and
Kunz 1988), few quantitative data on air movement in hibernacula used by
Indiana bats are available.

[Structure of the Hibernaculum]{.underline}

Myers (1964) observed that some caves are more attractive to bats and
that larger caves invariably offer a greater variety of habitats. Caves
that historically sheltered the largest populations of Indiana bats were
those with the largest volumes and structural diversity, thus ensuring
stable internal temperatures over wide ranges of external temperatures,
with a low likelihood of freezing (Tuttle and Kennedy 2002). Caves that
meet temperature requirements for Indiana bats are rare. The specific
configurations of hibernacula determine levels of temperature and
humidity and, thus, their habitat suitability (Humphrey 1978, Tuttle and
Stevenson 1978, LaVal and LaVal 1980, Tuttle and Kennedy 2002).

In many hibernacula in the central and southern United States, roosting
sites are near an entrance but may be deeper in a cave or mine if the
deeper location is where cold air flows and is trapped (Tuttle and
Stevenson 1978; R. Clawson, pers. comm., 1996). The best hibernation
sites in the central or southern United States provide a wide range of
vertical structure and a cave configuration that provides temperatures
ranging from below freezing to 13^o^C (55.4ºF) or above. These
hibernacula tend to have large volume and often have large rooms or
vertical passages below the lowest entrance. Large volume helps buffer
the cave environment against extreme changes in outside temperature, and
complex vertical structure offers a wide range of temperatures and,
therefore, diversity of roosting sites. Low chambers allow entrapment of
cold air that is stored throughout summer, providing arriving bats with
relatively low temperatures in early fall (Tuttle and Kennedy 2002).

In central and southern portions of the winter range, the best caves for
hibernation consistently have multiple entrances that permit
"chimney-effect" airflow. In winter, due to barometric pressure, cold
outside air enters one or more lower entrances while warmer air rises
and exits the cave through entrances that are at least a few feet higher
in elevation. The chimney effect cools the cave more than a single
entrance allows (Humphrey 1978, Tuttle and Kennedy 2002). In contrast,
aboveground temperatures are lower in the north, and successful
hibernation sites in northern hibernacula typically are further back
from entrances and not in areas with strong chimney effect airflow,
which may lead to subfreezing temperatures in areas between the
entrances in small caves (M. Tuttle, pers. comm., 1999).

[Fall and Spring Roosts near Hibernacula]{.underline}

Limited work has been done on roosting habitats of Indiana bats in
spring and fall, and most data are associated with areas near
hibernacula on the Daniel Boone National Forest in Kentucky (Kiser and
Elliot 1996, Gumbert et al. 2002). These studies show that Indiana bats
use roosting sites in the spring and fall that are similar to sites
selected during summer (i.e., bats typically roost under exfoliating
bark, with occasional use of vertical crevices in trees). Species of
trees used for these roosts also are similar to summer sites, although
various pines (*Pinus* spp.) commonly are occupied in spring and fall.
During this time, Indiana bats tend to roost more often as individuals
than in summer. Roost switching occurs every two to three days and
Indiana bats show fidelity to individual trees and roosting areas,
within and among years. Various trees used by the same individual tend
to be clustered in the environment, and roost trees most often are in
sunny openings in the forest created by human or natural disturbance.

During autumn, when Indiana bats swarm and mate at hibernacula, male
bats roost in nearby trees during the day and fly to the cave at night.
In Kentucky, Kiser and Elliott (1996) found male Indiana bats roosting
primarily in dead trees on upper slopes and ridge tops within 2.4 km

(1.5 mi) of their hibernaculum. During September, male Indiana bats in
West Virginia roosted within 5.6 km (3.5 mi) of their cave in trees near
ridge tops and often switched roost trees from day to day (C. Stihler,
pers. comm., 1996). One Indiana bat in Michigan roosted 2.2 km (1.4 mi)
away from the hibernaculum during fall swarming, and another chose trees
at a distance of 3.4 km (2.1 mi) (Kurta 2000).

**Summer Habitat**

[Microhabitat]{.underline}

*Bark or Crevice*

In summer, female Indiana bats usually roost under slabs of exfoliating
bark, and they occasionally use narrow cracks within trees (Callahan
1993; Kurta et al. 1993a, 1993b, 2002; Carter 2003; Britzke et al.
2006). For example, longitudinal crevices that formed when trees were
snapped by a tornado were used as primary roosts in Michigan (Kurta et
al. 2002). Although other species of bats frequently occupy tree hollows
that were created by rot or woodpeckers (Barclay and Kurta, in press),
such cavities are rarely used by maternity colonies of Indiana bats.
Even a "hollow" sycamore (*Platanus occidentalis*) that was used by
Indiana bats in Illinois (Kurta et al. 1993b) was a crevice in the bole
and not a rot-related or woodpecker-induced cavity (A. Kurta, pers.
comm., 2006).

*Species of Tree*

At least 33 species of trees have supplied roosts for female Indiana
bats and their young (Table 5), and 87 percent of the species used are
various ash (*Fraxinus*; 13 percent), elm (*Ulmus*; 13 percent), hickory
(*Carya*; 22 percent), maple (*Acer*; 15 percent), poplar (*Populus*; 9
percent), and oak (*Quercus*; 15 percent). At one time, it appeared that
oak and hickory were used more commonly at southern sites (Callahan et
al. 1997, Gardner et al. 1991b), whereas elm, ash, maple, and cottonwood
were occupied more often in northern areas (Kurta et al. 1996, 2002;
Whitaker and Brack 2002). Recent work, however, shows Indiana bats
occupying ash and elm in southern Illinois (Carter 2003) and hickories
in Vermont (Palm 2003), so type of tree seems related more to local
availability of trees with suitable structure than to broad regional
preferences for particular species of trees. Nonetheless, some common
trees, such as American beech (*Fagus grandifolia*), basswood (*Tilia
americana*), black cherry (*Prunus serotinus*), box elder (*A.
negundo*), and willows (*Salix* spp.) have rarely or never been used,
suggesting that they typically are not suitable, especially as primary
roosts.

Most (97 percent) roost trees of female Indiana bats at maternity sites
are deciduous species, except for a few coniferous trees recently
discovered in the Great Smoky Mountains (Harvey 2002, Britzke et al.
2003) and in New England (Palm 2003). Although this may indicate a
preference for deciduous trees, it more likely reflects availability.
Many other species of bats roost in conifers (Barclay and Kurta, in
press), and Indiana bats consistently use coniferous trees at some sites
during autumn swarming (Gumbert et al. 2002).

Many species of tree apparently make suitable roosts (Table 5), but some
species are preferred under certain circumstances. Kurta et al. (1996),
for example, demonstrated a preference by Indiana bats for green ash
(*F. pennsylvanica*) over silver maple (*A. saccharinum*) in Michigan,
and Carter (2003) showed that Indiana bats chose green ash and pin oak
(*Q. palustris*) more often than expected based on availability in
Illinois. Both studies occurred at sites with very high snag densities.
However, if suitable trees are less abundant, other factors that
influence roost selection (e.g., canopy cover, exposure to wind,
distance to foraging sites) may mask preferences displayed by bats in
areas of superabundant roosts.

*Living or Dead Trees*

Most trees occupied by female Indiana bats in summer are dead or nearly
so. Indiana bats sometimes are found under bark on large dead branches
within a living tree or on a dead trunk of a living tree with multiple
trunks. Indiana bats also occasionally roost under the naturally peeling
bark of living trees, most often shagbark (*C. ovata*) and shellbark
hickories (*C. lacinosa*) and occasionally white oak (*Q. alba*)
(Callahan et al. 1997, Sparks 2003, Brack et al. 2004). These trees may
be used especially as alternate roosts during exceptionally warm or wet
weather (Humphrey et al. 1977, Callahan et al. 1997). Carter (2003),
however, suggests that living trees are used as alternates only when
suitable dead trees are not available.

**Table 5.** Species of tree and type of roosting site used by Indiana
bats, based on studies conducted through 2004 (from Kurta 2005).

  ----------------- -------------- ------------- ----------- ------------ ----------- ------------ ----------------
  ***Scientific     ***Common      ***Type of    ***Number   ***Percent   ***Number   ***Percent   ***References*
  Name***           Name***        Roost**^a^*   of trees    of trees     of trees    of trees     *^b^***
                                                 used by     used by      used by     used by      
                                                 adult       adult        adult       adult        
                                                 females and females and  males***    males***     
                                                 young***    young***                              

  *Acer rubrum*     Red maple      B, C          7           1.8          13          5.4          2, 4, 9, 12, 13,
                                                                                                   16, 17

  *Acer             Silver maple   B             25          6.4          1           0.4          5, 6, 8, 13, 18,
  saccharinum*                                                                                     19

  *Acer saccharum*  Sugar maple    B, C          18          4.6          2           0.8          1, 2, 8, 16-20

  *Acer* sp*.*      Unidentified   B             9           2.3          0           0.0          13
                    maple                                                                          

  *Betula           Yellow birch   ?             2           0.5          0           0.0          2, 16
  alleghaniensis*                                                                                  

  *Betula lenta*    Sweet birch    B             1           0.3          0           0.0          3

  *Carya            Bitternut      B             3           0.8          1           0.4          8, 11, 18, 19
  cordiformis*      hickory                                                                        

  *Carya glabra*    Pignut hickory B             0           0.0          3           1.3          12, 17

  *Carya lacinosa*  Shellbark      B             4           1.0          0           0.0          18, 19
                    hickory                                                                        

  *Carya ovata*     Shagbark       B             78          19.8         22          9.2          2, 5, 6, 8-13,
                    hickory                                                                        16-21

  *Carya tomentosa* Mockernut      ?             0           0.0          7           2.9          9
                    hickory                                                                        

  *Celtis           Northern       B             1           0.3          0           0.0          18, 19
  occidentalis*     hackberry                                                                      

  *Cornus florida*  Flowering      ?             0           0.0          4           1.7          9
                    dogwood                                                                        

  *Fagus            American beech ?             1           0.3          0           0.0          2
  grandifolia*                                                                                     

  *Fraxinus         White ash      C             1           0.3          0           0.0          5
  americana*                                                                                       

  *Fraxinus nigra*  Black ash      B             4           1.0          3           1.3          13

  *Fraxinus         Green ash      B, C          46          11.7         4           1.7          2, 6, 13, 18, 19
  pennsylvanica*                                                                                   

  *Gleditsia        Honeylocust    B             2           0.5          0           0.0          7
  triacanthos*                                                                                     

  *Juglans cinerea* Butternut      B             1           0.3          0           0.0          20

  *Juglans nigra*   Black walnut   B             1           0.3          0           0.0          18, 19

  *Liriodendron     Tulip tree     B             1           0.3          6           2.5          9, 15
  tulipifera*                                                                                      

  *Ostrya virgiana* Hophornbeam    B             1           0.3          0           0.0          20

  *Oxydendrum       Sourwood       ?             0           0.0          9           3.8          9, 12
  arboreum*                                                                                        

  *Pinus echinata*  Shortleaf pine B             2           0.5          70          29.3         3, 9

  *Pinus rigida*    Pitch pine     B             1           0.3          6           2.5          3, 9

  *Pinus* sp.       Unidentified   B             1           0.3          4           1.7          3, 10, 21
                    pine                                                                           

  *Pinus strobus*   White pine     B, C          8           2.0          0           0.0          16, 20

  *Pinus            Virginia pine  ?             0           0.0          15          6.3          9, 12
  virginiana*                                                                                      

  *Platanus         Sycamore       C             2           0.5          0           0.0          14, 18, 19
  occidentalis*                                                                                    

  *Populus          Cottonwood     B, C          25          6.4          0           0.0          5, 6, 8, 13, 18,
  deltoides*                                                                                       19, 21

  *Populus* sp.     Unidentified   B             5           1.3          0           0.0          20
                    poplar                                                                         

  *Populus          Trembling      B             5           1.3          0           0.0          2, 16
  tremuloides*      aspen                                                                          

  *Quercus alba*    White oak      B             15          3.8          18          7.5          5, 8, 9, 17, 21

  *Quercus          Scarlet oak    ?             0           0.0          5           2.1          9, 12
  coccinea*                                                                                        

  *Quercus falcata* Spanish oak    ?             0           0.0          1           0.4          9

  *Quercus          Shingle oak    B             0           0.0          1           0.4          8
  imbricaria*                                                                                      

  *Quercus          Pin oak        B             8           2.0          0           0.0          6
  palustris*                                                                                       

  *Quercus prinus*  Chestnut oak   ?             0           0.0          6           2.5          9

  *Quercus rubra*   Red oak        B             30          7.6          9           3.8          3, 4, 5, 8-10,
                                                                                                   12, 13, 21

  *Quercus* sp.     Unidentified   B             3           0.8          0           0.0          20
                    oak                                                                            

  *Quercus          Post oak       B             3           0.8          2           0.8          8
  stellata*                                                                                        

  *Quercus          Black oak      B             0           0.0          2           0.8          9, 17
  velutina*                                                                                        

  *Robinia          Black locust   B, C          12          3.1          0           0.0          2, 20
  pseudoacacia*                                                                                    

  *Sassafras        Sassafras      B, Ca         0           0.0          2           0.8          8
  albidium*                                                                                        

  *Tilia americana* Basswood       B             1           0.3          0           0.0          20

  *Tsuga            Eastern        B             3           0.8          0           0.0          2, 3, 20
  canadensis*       hemlock                                                                        

  *Ulmus americana* American elm   B             35          8.9          14          5.9          2, 4, 8, 9, 13,
                                                                                                   16-22

  *Ulmus rubra*     Slippery elm   B, C          9           2.3          9           3.8          4, 7, 8, 9, 13,
                                                                                                   21

  *Ulmus* sp.       Unidentified   B             8           2.0          0           0.0          6
                    elm                                                                            

  Unidentified                     B             11          2.8          0           0.0          2, 6, 13

  **Total**                                      393         100.0        239         100.0        
  ----------------- -------------- ------------- ----------- ------------ ----------- ------------ ----------------

^a^ Type of roost: B = under bark; C = in crevice; and Ca = in cavity.
Not all references indicated specifically which species of tree provided
a bark vs. a crevice roost.

^b^ References are: 1, Belwood 2002; 2, Britzke 2003; 3, Britzke et al.
2003; 4, Butchkoski and Hassinger 2002; 5, Callahan 1993; 6, Carter
2003; 7, Chenger 2003; 8, Gardner et al. 1991b; 9, Gumbert 2001; 10,
Harvey 2002; 11, Humphrey and Cope 1977; 12, Kiser and Elliott 1996; 13,
Kurta and Rice 2002; 14, Kurta et al. 1993b; 15, A. Kurta, pers. comm.,
2004; 16, Palm 2003; 17, Schultes 2002; 18, Sparks 2003; 19, D. Sparks
Indiana State University, pers. comm., 2004.; 20, K. Watrous, pers.
comm., 2004; 21, Whitaker and Brack 2002; and 22, L. Winhold, Eastern
Michigan University, pers. comm., 2004.

###### Size of Tree 

Roost trees vary in size (Tables 6 and 7). Although minimum diameter
reported so far is 6.4 cm

(2.5 in) for a tree used by males (Gumbert 2001) and 11 cm (4.3 in) for
one occupied by females (Britzke 2003), such small trees have not been
documented as primary roosts. Average diameter of roost trees (primary
and alternate) is 62, 55, and 41 cm (24, 22, and 16 in) for Indiana,
Missouri, and Michigan, respectively (Callahan et al. 1997, Kurta and
Rice 2002, Whitaker and Brack 2002). Differences in average diameter
among states likely reflect differences in species of tree contained in
each sample - the Indiana sample is dominated by cottonwood; Missouri,
by oak and hickory; and Michigan, by ash. The smallest mean diameter in
Table 6 (28 cm or 11 in) is for five trees in Pennsylvania; however, the
primary roost for this colony was a building, and no tree sheltered more
than four bats (Butchkoski and Hassinger 2002).

Larger-diameter trees presumably provide thermal advantages and more
spaces for more bats to roost. As with most tree-roosting bats (Hayes
2003, Barclay and Kurta, in press), female Indiana bats probably select
trees, especially primary roosts, that are larger in diameter than
nearby, apparently suitable, but unoccupied trees (Kurta et al. 1996,
2002; Britzke et al. 2003; Palm 2003; Sparks 2003). Nevertheless,
whether a statistical difference in diameter is detected between roost
and randomly selected trees is partly dependent on the definition of a
"suitable" or "available" tree. Differences between roosts and random
trees have been found when the minimum diameter of available trees is
set at 4.5, 10, or 15 cm (2, 4, or 6 in) (Kurta et al. 1996, 2002; Palm
2003; Sparks 2003) but not at 18.5 or 25 cm (7 or 10 in) (Callahan et
al. 1997, Carter 2003). Inclusion of small trees in the pool of randomly
selected trees seems justified, because there are numerous instances of
one or more Indiana bats using them; hence, they are "available" to the
bats.

Average heights of roost trees range from 16 to 26 m (52 to 85 ft)
(Tables 6 and 7). Variation in height among studies likely reflects
species differences in the sample of roost trees but also in the manner
in which the trees died. For example, roost trees at one site in
Michigan were killed slowly by inundation and had an average height of
25 m (82 ft), whereas roosts at a second site were broken in a windstorm
and averaged only 18 m (59 ft) (Kurta et al. 1996, 2002). Minimum tree
heights are 3 m (10 ft) for an alternate roost (Carter 2003) and 3.7 m
(12 ft) for a primary roost (Callahan 1993). Absolute height of the
roost tree probably is less important than height relative to
surrounding trees, because relative height can affect the amount of
solar radiation impinging on the tree (e.g., Kurta and Rice 2002), ease
of finding the tree, and ease of safely approaching the roost in flight
(Barclay and Kurta, in press, Hayes 2003).

Among 16 studies, mean height of the exit, which also is assumed to be
the height of the roosting area, was 5 to 16 m (16 to 52 ft), although
the mean more commonly ranged from 7 to 10 m (23 to 33 ft) (Table 6).
Nevertheless, minimum exit height for a primary roost is 1.8 m (6 ft);
for an alternate roost it is only 0.6 m (2 ft) (Callahan 1993). Height
of the exit is correlated with height of the tree (Kurta et al. 2002).

**Table 6.** Means or ranges (n) for roost parameters of adult female
and/or young Indiana bats in various studies conducted through 2004
(from Kurta 2005). All means were rounded to the nearest whole number to
facilitate comparison. Means were taken from the indicated references or
calculated based on tabulated data contained in each reference.

+-----------+-----+-----+-----+------+-----+-------------------------+
| ***Loc    | **  | *** | *** | ***  | *** | ***Reference***         |
| ation/par | *Di | Hei | Hei | Bark | Can |                         |
| ameter*** | ame | ght | ght | r    | opy |                         |
|           | ter | of  | of  | emai | co  |                         |
|           | of  | t   | e   | ning | ver |                         |
|           | t   | ree | xit | (    | (%) |                         |
|           | ree | (m) | or  | %)** | *** |                         |
|           | (   | *** | *** | ^a^* |     |                         |
|           | cm) |     |     |      |     |                         |
|           | *** |     | **  |      |     |                         |
|           |     |     | *ro |      |     |                         |
|           |     |     | ost |      |     |                         |
|           |     |     | ing |      |     |                         |
|           |     |     | a   |      |     |                         |
|           |     |     | rea |      |     |                         |
|           |     |     | (m) |      |     |                         |
|           |     |     | *** |      |     |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Illinois  | 39  | 18  | 10  | 47   | 36  | Carter, 2003            |
|           | (   | (   | (   | (47) | (   |                         |
|           | 47) | 47) | 47) |      | 47) |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Illinois  | 37  |     |     |      |     | Gardner et al., 1991b   |
|           | (   |     |     |      |     |                         |
|           | 48) |     |     |      |     |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Illinois  | 56  | 16  | 5   |      |     | Kurta et al., 1993b     |
|           | (1) | (1) | (1) |      |     |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Indiana   |     |     |     |      |     | Humphrey et al., 1977   |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Indiana   | 47  | 23  | 9   |      |     | Sparks, 2003            |
|           | (   | (   | (   |      |     |                         |
|           | 27) | 27) | 25) |      |     |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Indiana   | 62  |     |     |      |     | Whitaker and Brack,     |
|           | (   |     |     |      |     | 2002                    |
|           | 17) |     |     |      |     |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Michigan  | 41  | 25  | 10  |      | 0   | Foster and Kurta, 1999; |
|           | (   | (   | (   |      | -20 | Kurta et al. 1996       |
|           | 23) | 23) | 23) |      | (   |                         |
|           |     |     |     |      | 23) |                         |
|           |     |     |     |      | ^b^ |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Michigan  | 42  | 18  | 10  |      | 31  | Kurta et al. 2002; A.   |
|           | (   | (   | (   |      | (   | Kurta, pers. comm.,     |
|           | 38) | 38) | 34) |      | 35) | 2004                    |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Michigan  | 43  | 26  | 16  | 60   | 54  | L. Winhold, pers.       |
|           | (3) | (3) | (3) | (3)  | (3) | comm., 2004             |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Missouri  | 54  |     |     | 73   | 67  | Callahan, 1993;         |
|           | (   |     |     | (21) | (   | Callahan et al., 1997   |
|           | 38) |     |     |      | 38) |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| New York, | 46  | 19  |     |      |     | Britzke, 2003           |
|           | (   | (   |     |      |     |                         |
| V         | 31) | 34) |     |      |     |                         |
| ermont^c^ |     |     |     |      |     |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| New York, | 48  | 21  | 7   |      |     | K. Watrous, pers. comm. |
| Vermont   | (   | (   | (   |      |     | 2004                    |
|           | 50) | 50) | 18) |      |     |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Pen       | 28  | 20  | 8   | 51   |     | Butchkoski and          |
| nsylvania | (5) | (5) | (5) | (5)  |     | Hassinger, 2002         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| North     | 46  | 18  |     | 46   |     | Britzke et al., 2003    |
| Carolina, | (8) | (8) |     | (18) |     |                         |
|           |     |     |     |      |     |                         |
| Tennessee |     |     |     |      |     |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Ohio      | 38  | 21  |     |      |     | Belwood, 2002           |
|           | (2) | (1) |     |      |     |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| Vermont   | 50  |     |     | 77   | 88  | Palm, 2003              |
|           | (   |     |     | (13) | (   |                         |
|           | 20) |     |     |      | 20) |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| **Average | 45  | 20  | 9 ± | 59 ± | 50  |                         |
| ± SE**^d^ | ± 2 | ± 1 | 1   | 5    | ±   |                         |
|           |     |     |     |      | 10  |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| **Number  | 15  | 11  | 8   | 6    | 6   |                         |
| of        |     |     |     |      |     |                         |
| studies** |     |     |     |      |     |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+
| **Number  | 359 | 231 | 141 | 88   | 128 |                         |
| of        |     |     |     |      |     |                         |
| trees**   |     |     |     |      |     |                         |
+-----------+-----+-----+-----+------+-----+-------------------------+

^a^ Total bark on tree, not just loose and peeling.

^b^ A liberal value of 20% was used when calculating the overall mean.

^c^ Trees were located primarily in April and early May; all other
studies were mid-May to mid-August.

^d^ Calculations of overall average and SE used the unweighted means
from the various studies. Weighting each study, based on the number of
trees, gave very similar results.

**Table 7.** Means (n) for roost parameters and roosting behavior of
adult male Indiana bats in various studies conducted through 2004 (from
Kurta 2005). All means were rounded to the nearest whole number to
facilitate comparison. Means were taken from the indicated references or
calculated based on tabulated data in each reference.

+-----------+-----+-----+-----+-----+-----+------------------------+
| ***Loc    | **  | *** | *** | *   | *** | ***Reference***        |
| ation/*** | *Di | Hei | Hei | **B | Can |                        |
|           | ame | ght | ght | ark | opy |                        |
| ***par    | ter | of  | of  | rem | co  |                        |
| ameter*** | of  | t   | e   | ain | ver |                        |
|           | t   | ree | xit | ing | (%) |                        |
|           | ree | (m) | or  | (%) | *** |                        |
|           | (   | *** | *** | **^ |     |                        |
|           | cm) |     |     | a^* |     |                        |
|           | *** |     | **  |     |     |                        |
|           |     |     | *ro |     |     |                        |
|           |     |     | ost |     |     |                        |
|           |     |     | ing |     |     |                        |
|           |     |     | a   |     |     |                        |
|           |     |     | rea |     |     |                        |
|           |     |     | (m) |     |     |                        |
|           |     |     | *** |     |     |                        |
+-----------+-----+-----+-----+-----+-----+------------------------+
| Illinois  | 32  |     |     |     |     | Gardner et al., 1991b  |
|           | (   |     |     |     |     |                        |
|           | 18) |     |     |     |     |                        |
+-----------+-----+-----+-----+-----+-----+------------------------+
| Indiana   | 38  | 25  |     | 25  | 49  | Brack et al., 2004;    |
|           | (   | (1) |     | (   | (   | Whitaker and Brack,    |
|           | 12) |     |     | 12) | 12) | 2002                   |
|           |     |     |     | ^b^ |     |                        |
+-----------+-----+-----+-----+-----+-----+------------------------+
| Iowa      | 43  | 20  | 13  |     |     | Chenger, 2003          |
|           | (1) | (1) | (1) |     |     |                        |
+-----------+-----+-----+-----+-----+-----+------------------------+
| Kentucky  | 31  | 15  |     |     | 58  | Gumbert, 2001; Gumbert |
| ^c^       | (1  | (1  |     |     | (1  | et al., 2002           |
|           | 69) | 69) |     |     | 69) |                        |
+-----------+-----+-----+-----+-----+-----+------------------------+
| Kentucky  | 31  |     |     | 61  |     | Kiser and Elliot, 1996 |
|           | (8) |     |     | (8) |     |                        |
+-----------+-----+-----+-----+-----+-----+------------------------+
| Michigan  | 37  | 21  | 9   |     |     | Kurta and Rice, 2002   |
|           | (9) | (9) | (9) |     |     |                        |
+-----------+-----+-----+-----+-----+-----+------------------------+
| Ohio      | 32  | 16  |     | 56  | 81  | Schultes, 2002         |
|           | (   | (   |     | (   | (   |                        |
|           | 14) | 14) |     | 14) | 14) |                        |
+-----------+-----+-----+-----+-----+-----+------------------------+
| Pen       | 20  | 18  | 9   | 53  |     | Butchkoski and         |
| nsylvania | (2) | (2) | (2) | (2) |     | Hassinger, 2002        |
+-----------+-----+-----+-----+-----+-----+------------------------+
| **Average | 33  | 18  | 10  | 57  | 63  |                        |
| ± SE**^d^ | ± 2 | ± 1 | ± 1 | ± 1 | ±   |                        |
|           |     |     |     |     | 10  |                        |
+-----------+-----+-----+-----+-----+-----+------------------------+
| **Number  | 8   | 5   | 3   | 3   | 3   |                        |
| of        |     |     |     |     |     |                        |
| studies** |     |     |     |     |     |                        |
+-----------+-----+-----+-----+-----+-----+------------------------+
| **Number  | 219 | 189 | 12  | 25  | 128 |                        |
| of        |     |     |     |     |     |                        |
| trees**   |     |     |     |     |     |                        |
+-----------+-----+-----+-----+-----+-----+------------------------+

^a^ Total bark on tree, not just exfoliating, unless otherwise noted.

^b^ Amount of exfoliating bark; not used in calculation of mean.

^c^ Data collected from April through October; all others apparently
were mid-May to mid-August. Data from Gumbert (2001) are confounded
slightly with trees used by adult females (7.6% of bats located were
female) and by multiple counting of trees (9.2%) used in more than one
season (spring, summer, autumn).

^d^ Calculations of overall average and SE used the unweighted means
from the various studies. Weighting each study, based on the number of
trees, gave very similar results.

*Other Factors Affecting Access and Sunlight*

In addition to height, other factors influence the amount of sunlight
striking a roost tree and simultaneously impact the ease and safety of
access for a flying bat (Barclay and Kurta, in press). For example,
roosts of the Indiana bat, especially primary roosts, typically are
found in open situations, although definitions of "open" vary (Gardner
et al. 1991b; Kurta et al. 1993b, 1996, 2002; Callahan et al. 1997;
Carter 2003; Palm 2003; Sparks 2003). The immediate vicinity of a roost,
especially a primary roost, often is open forest, or roosts may occur
along the edge of a woodlot, in gaps within a forest, in a copse of dead
trees, as part of a wooded fenceline, in grazed woodlands, or in
pastures with scattered trees. When present in denser forests, primary
roost trees often extend above the surrounding canopy (e.g., Callahan et
al. 1997). Roosts occasionally occur in low-density residential areas
with mature trees (e.g., Belwood 2002).

Mean values of canopy cover are highly variable among studies, ranging
from \<20 to 88 percent (Tables 6 and 7). Reports of roost trees in
closed-canopy forests (e.g., Gardner et al. 1991b reported that 32 of 48
roost trees examined in Illinois occurred within forests with 80 percent
to 100 percent canopy closure) may appear to conflict with statements
that primary roosts are generally located in areas with high solar
exposure. There are several points to consider in evaluating this
apparent discrepancy. First, some variation undoubtedly is related to
differences in methodology, because virtually every study measures
canopy cover in a different way. Second, roosts found in closed-canopy
forests, particularly primary roosts, are often associated with natural
or man-made gaps (e.g., openings created when nearby trees fall,
riparian edges, trail or forest road edges). Although the forest may be
accurately described as closed canopy, the canopy in the immediate
vicinity of the roost tree may have an opening that allows for solar
radiation to reach the roost. Indiana bat roosts have been created by
the death of a single large-canopy tree (A. King, pers. comm., 2005).

Regional differences in roost characteristics also account for some of
the variability in canopy cover in the vicinity of Indiana bat roost
sites. For example, average values for canopy cover may be higher in
areas where many living shagbark hickories are used as alternate roosts
(e.g., Palm 2003), compared with sites where most roost trees are dead
and leafless (e.g., Kurta et al. 1996, 2002). In addition, Indiana bats
may use sites that are more shaded during warm weather (e.g., Callahan
et al. 1997). Sites in northern areas (e.g., Kurta et al. 1996) or at
high altitudes (e.g., Britzke et al. 2003) are exposed to cooler
temperatures, so use of highly shaded roosts probably is less common in
these areas and may be restricted to periods of unusually warm weather,
which may not occur every year. For example, a colony of 30 Indiana bats
in Michigan used a tree with 58 percent canopy cover and an open
southern exposure, but all bats shifted to a nearby tree with 90 percent
canopy cover after a prolonged period of abnormally high ambient
temperature (\>32°C or 89.6°F) (L. Winhold, pers. comm., 2005). In a
typical year, however, Indiana bats generally do not use such highly
shaded sites in Michigan (Kurta et al. 1996, 2002).

Access by a flying bat and amount of sunlight striking the roost could
be affected negatively by presence on the trunk of living or dead vines,
such as wild grape (*Vitis* spp.) or Virginia creeper (*Parthenocissus
quinquefolia*). In Michigan, all roost trees (n = 76) lacked vines at or
above the roosting area, although no comparison was made with randomly
selected trees (Kurta and Rice 2002; A. Kurta, pers. comm., 2005). A
roost shaded by poison ivy (*Rhus radicans*) was observed in New York
(V. Brack, pers. comm., 2006).

*Amount of Bark Remaining*

Amount of bark remaining on a tree is another parameter that often is
measured, although not always in the same way. Some biologists record
the total amount of bark remaining on a tree, whether the bark is
suitable for roosting or not (e.g., Callahan et al. 1997), whereas other
researchers record only the amount of exfoliating bark under which a bat
might roost (e.g., Gardner et al. 1991b; Kurta et al. 1996, 2002). The
two techniques must be distinguished because they mean different things;
total bark indicates stage of decay, whereas exfoliating bark indexes
roosting opportunities. Consequently, the two methods can yield
different results. For example, a randomly selected tree that recently
died may be covered totally by bark and yield a value of 100 percent;
however, the same tree would be totally unsuitable for roosting, because
all bark is still tight to the trunk. Although there is potential for
confusion, neither the amount of total bark nor the amount of
exfoliating bark is useful as a predictor of current occupancy by
Indiana bats (Kurta et al. 1996, 2002; Callahan et al. 1997; Gumbert
2001; Britzke et al. 2003; Carter 2003; Palm 2003).

*Primary vs. Alternate Roosts*

Despite the number of studies of Indiana bats, few reports have
statistically compared the attributes of primary roosts and alternate
trees. In Missouri, primary trees were more likely to be in open
situations, as opposed to the interior of the woods, and more likely to
be dead trees, rather than living shagbark hickories; alternate roosts,
in contrast, were more variable and could be either interior or open
trees (Callahan et al. 1997). No other statistical differences were
found between primary and alternate trees (Callahan et al. 1997). In
Michigan, both primary and alternate roosts typically were in open
sites, and there was no statistical difference between primary and
alternate roosts in tree height, exit height, canopy cover, solar
exposure, or amount of bark (Kurta et al. 1996, 2002). In addition, mean
diameter did not differ, although diameter of primary trees was less
variable than that of alternate roosts in Michigan (Kurta et al. 2002).

One proposed function of frequent roost switching by tree-living bats is
that individuals are evaluating new trees for future use (Barclay and
Kurta, in press). Hence, primary roosts likely were alternate roosts
initially, although most alternate roosts never become primary roosts.
If so, an inability to detect statistical differences between primary
and alternate roosts is understandable, because primary roosts represent
a small subset of all sites that were evaluated by the bats. Alternate
roosts probably are more variable in most parameters than are primary
roosts (Callahan et al. 1997; Kurta et al. 2002), although most reports
do not address the degree of variation.

*A Summary of Characteristics of a Typical Primary Roost*

Individual Indiana bats have been found roosting in a large number of
types of trees and situations, but it is possible to summarize the
essential characteristics of a typical primary roost.

A typical primary roost is located under exfoliating bark of a dead ash,
elm, hickory, maple, oak, or poplar, although any tree that retains
large, thick slabs of peeling bark probably is suitable. Average
diameter of maternity roost trees is 45 cm (18 in) (Table 6) and average
diameter of roosts used by adult males is 33 cm (13 in) (Table 7).
Height of the tree (snag) is greater than 3 m (10 ft), but height of the
roosting tree is not as important as height relative to surrounding
trees and the position of the snag relative to other trees, because
relative height and position affect the amount of solar exposure.
Primary roosts usually receive direct sunlight for more than half the
day. Access to the roost site is unimpeded by vines or small branches.
The tree is typically within canopy gaps in a forest, in a fenceline, or
along a wooded edge. Primary roosts usually are not found in the middle
of extensive open fields but often are within 15 m (50 ft) of a forest
edge. Primary roosts usually are in trees that are in early-to-mid
stages of decay.

*Roosts during Spring*

Most studies of roosting preferences by adult females have occurred
during the summer maternity season, which is typically defined as 15 May
to 15 August. However, Indiana bats first arrive at their summer
locations as early as April or early May (Humphrey et al. 1977, Kurta
and Rice 2002). During this mid-spring period, adult females occupy
trees that are similar to those used in summer in terms of species,
size, and structure (Britzke 2003, Butchkoski and Turner 2005, Britzke
et al. 2006).

*Sexual Differences in Habitat Use*

Adult males of most species of bats probably enter torpor in summer more
frequently than reproductive females, and hence, males probably can use
a wider range of roosting situations than females (Barclay and Kurta, in
press). Some adult male Indiana bats form colonies in caves in summer
(Hall 1962), but most are solitary and roost in trees. Adult males have
been radiotracked to at least 239 trees of 26 species in eight states
(Table 5). Males occasionally roost with reproductive females in the
same tree, and males have been tracked to trees up to 95 cm (37 in) in
diameter (Kurta and Rice 2002). However, males accept small trees more
often than do females, and, consequently, mean diameter of trees used by
females and young (18 in or 45 cm; n=359) is 36 percent greater than the
average for males (13 in or 33 cm; n = 219) (Tables 6 and 7). Males also
may be more tolerant of shaded sites.

Like female Indiana bats, adult males roost primarily under bark and
less often in narrow crevices, but two males have been tracked to small
cavities in trees (Gardner et al. 1991b, Gumbert 2001). Tree species
used by males generally are similar to those chosen by females, although
males have been found more frequently in pines (Table 5). The large
number of conifers used by males, however, likely reflects the abundance
of these trees in the forest surrounding certain caves in Kentucky,
where the most intensive studies of male roosting have occurred (Kiser
and Elliott 1996, Gumbert 2001).

*Artificial Roosts*

During summer, female and juvenile Indiana bats roost almost always in
trees, as do adult males. Adult females, however, apparently used a
crevice in a utility pole in Indiana (Ritzi et al. 2005), and adult
males were found under metal brackets on utility poles in Arkansas
(Harvey 2002). There also are a few instances of adult male and juvenile
Indiana bats day-roosting under concrete bridges in Indiana (reviewed in
Kiser et al. 2002). Although a few Indiana bats have been captured in
buildings during migration before 15 May or after 15 August (Belwood,
2002), only four maternity colonies have been located in buildings.
These include an abandoned church in Pennsylvania (Butchkoski and
Hassinger, 2002), two houses in New York (A. Hicks, pers. comm., 2004;
V. Brack, pers comm., 2005), and a barn in Iowa (Chenger 2003).
Nevertheless, there are almost 400 roost trees for female Indiana bats
indicated in Table 5, suggesting that use of buildings by maternity
colonies is uncommon.

Similarly, Indiana bats rarely occupy bat houses. Reproductive females
from the church in Pennsylvania also used a large free-standing bat
house as an alternate roost, as well as a smaller bat house wrapped in
aluminum sheeting (Butchkoski and Hassinger 2002, Butchkoski and Turner
2005). Before 2003, the only other published records of Indiana bats
using bat houses were two solitary juvenile males using different
bird-house-style bat boxes and a group of females in a rocket box after
the reproductive period (Carter et al. 2001, Ritzi et al. 2005).
However, Ritzi et al. (2005) recently found groups of reproductive
females using two bird­house-style bat boxes for prolonged periods in
Indiana. Use of these artificial structures coincided with destruction
of two primary roost trees, and the authors speculated that portions of
the colony were using the boxes as temporary replacements. The boxes had
been in place for 11 years before being occupied and were two of 3,204
artificial structures of various styles constructed.

[Landscape Structure and Macrohabitat]{.underline}

*Distance to Environmental Features*

Distances from roosts to nearby environmental features have rarely been
measured. Trees used by a colony in Illinois were closer to unpaved than
paved roads and closer to intermittent streams than to perennial
streams, although no comparison was made with randomly selected points
(Gardner et al. 1991b). In Michigan, roost trees were closer to
perennial streams than random locations, but there was no difference
between roosts and random points in distance to roads of any type or to
lakes/ponds (Kurta et al. 2002).

Insectivorous bats typically obtain 20 to 26 percent of their daily
water from drinking (Kurta et al. 1989, 1990), and one might think that
roost trees should be closer to water sources than random points. In
upland areas lacking streams or lakes, Indiana bats, especially adult
males, have been captured while flying over wildlife ponds and at
water-filled road ruts (e.g., Wilhide et al. 1998), suggesting that the
bats might be attracted to these artificial sources of water. However,
water sources are ubiquitous in most areas where Indiana bat maternity
roosts have been found. At one maternity site in Michigan, for example,
average distance from a random point to a perennial stream is only 910 m
(2,986 ft) and to a lake or pond, 541 m (1,775 ft ) (Kurta et al. 2002).
Such distances are energetically insignificant to a flying mammal
(Barclay and Kurta, in press), and distance to water likely does not
impact selection of individual trees, at least in those areas of the
continent where most maternity colonies of Indiana bats have been
located. Although distance to water probably is not a factor in
day-to-day roost selection, accessible sources of water might affect
location of the home range of a colony on a broader landscape, i.e.,
colonies may locate in areas of more abundant, accessible sources of
water (Carter et al. 2002).

*Commuting Corridors*

Many species of bats, including the Indiana bat, consistently follow
tree-lined paths rather than crossing large open areas (Gardner et al.
1991b, Verboom and Huitema 1997, Carter 2003, Chenger 2003, Murray and
Kurta 2004, Winhold et al. 2005). Therefore, suitable patches of forest
may not be available to Indiana bats unless a wooded corridor connects
the patches (i.e., a component of suitable habitat may be the
connectedness of different forest patches). Unfortunately, biologists do
not know how large an open area must be before Indiana bats hesitate or
refuse to cross. There are observations of Indiana bats crossing
interstate highways (Brack and Whitaker 2004) and open fields (Brack
1983). V. Brack (pers. comm., 2006) noted that he has observed Indiana
bats following linear features not associated with tree cover, such as a
treeless channelized ditch. Murray and Kurta (2004), however, showed
that Indiana bats increased commuting distance by 55 percent to follow
tree-lined paths, rather than flying over large agricultural fields,
some of which were at least 1-km (0.6 mi) wide (Winhold et al. 2005).

*Surrounding Habitats*

At one time, the Indiana bat was considered a riparian specialist
(Humphrey et al. 1977), but further study demonstrated that this
categorization is not valid. Maternity roosts of some colonies have been
found primarily in riparian zones (Humphrey et al. 1977), bottomland and
floodplain habitats (Carter 2003), upland communities (Gardner et al.
1991b, Palm 2003), or in a mix of riparian and upland habitat (Callahan
1993). Indiana bats in Michigan (Kurta et al. 2002), in contrast,
preferred roosting in wooded wetlands; although some roosts were in the
floodplain of a major river, most were in low areas not associated with
the river. Differences among studies probably reflect, at least partly,
the varying location of intact woods in different agricultural
landscapes (Murray and Kurta 2002, 2004).

Although the presence of female Indiana bats (i.e., maternity colonies)
generally is not correlated with high forest cover, several studies
suggest a correlation with the density of suitable roost trees. Miller
et al. (2002) compared landscape and macrohabitat features surrounding
sites where female Indiana bats were caught (i.e., maternity colonies)
to sites where they were not caught in Missouri. While the study found
that landscape features (e.g., forest cover) were too variable to
accurately show differences between occupied and unoccupied sites, the
occupied sites contained a higher density of large-diameter trees.
Similarly, after analyzing a model for predicting habitat suitability,
Farmer et al. (2002) concluded that the amount of land in forest, number
of different habitats available, and area of water were not useful for
predicting presence of Indiana bats. However, they reported that the
utility of the model was based on a single component - density of
suitable roost trees - and Indiana bats were more likely to occur in
areas with a high density of potential roost trees (see also Clark et
al. 1987).

Composition of the landscape surrounding a colony's home range was
determined for a few maternity colonies. In Illinois, 67 percent of the
land near one colony was agricultural, 33 percent was forested, and 0.1
percent consisted of farm ponds (Gardner et al. 1991b). In Michigan,
land cover consisted of 55 percent agricultural land, 19 percent
wetlands (including lowland hardwood forest), 17 percent other forests,
6 percent urban development, and 3 percent lakes/ponds/rivers (Kurta et
al. 2002). Land within 4 km (2.5 mi) of primary roosts in Indiana
contained an average of 37 percent deciduous forest cover, although
forest cover varied from 10 to 80 percent (L. Pruitt, pers. comm.,
2005).

Using GIS, Carter et al. (2002) compared habitats in circles that were 2
km (1.2 mi) in diameter surrounding all roost trees known in Illinois
with habitat surrounding randomly selected locations. Areas around
roosts had fewer and smaller urban patches and more and larger patches
of closed-canopy deciduous forest compared with random sites. Area and
number of patches of coniferous forest did not differ between roosting
and random locations, but roosting areas had more patches of water
(e.g., ponds, lakes) than random sites. Finally, while roosts typically
occurred in highly fragmented forests, roosting areas contained more
patches of bottomland forest and agriculture than randomly chosen
circles. Even though roosting areas contained more agriculture patches
than randomly chosen circles, the overall area of agriculture was less
for roosting areas. With regard to bottomland forests, the mean patch
size of bottomland forest around known roost trees was 35.9 ha (88.7 ac)
and the total area was 82.7 ha (204.4 ac), as compared to a mean patch
size of bottomland forest around the randomly chosen circles of 1.5 ha

(3.7 ac) and 2.7 ha (6.7 ac) for total area.

A Missouri study found that Indiana bats selected maternity roost sites
based upon tree size, tree species, and surrounding canopy cover
(Callahan 1993). In his study, the amount of forest within a 3-km (1.9
mi) radius of four maternity sites varied from 19 to 30 percent, while
the amount of forest within a "minimum roost tree range" (i.e., the
minimum-sized circle that would encompass all roost trees used by a
colony) around the same four colonies ranged from 23 to 53 percent; the
amount of agricultural land within the larger radius ranged from 58 to
81 percent, while the amount of agricultural land within the smaller
radius ranged from 47 to 77 percent (Callahan 1993). Callahan suggested
that the potential preference of Indiana bat maternity colonies for
larger forested tracts would increase the chances that a suitable range
of roost trees would be available for the colonies.

On a much larger scale, Gardner and Cook (2002) examined land cover in
132 counties in the United States for which there was evidence of
reproduction by Indiana bats. Non-forested habitats, consisting
primarily agricultural land, made up 75.7 percent of the total land area
in those counties. Deciduous forest covered 20.5 percent of the land,
whereas coniferous forests and mixed coniferous/deciduous woodland
occupied 3.4 percent.

Most Indiana bat maternity colonies have been found in agricultural
areas with fragmented forests. Most females from the major hibernacula
in Indiana, Kentucky, and Missouri migrate north for summer, into
agricultural landscapes of the Midwest (Gardner and Cook 2002, Whitaker
and Brack 2002). Similarly, recently discovered colonies in Vermont and
New York also occur in agricultural regions and other areas with
fragmented forests. Bats from hibernacula in New York were followed with
aircraft as they left hibernation and migrated to agricultural areas of
the Lake Champlain Valley and southern New York (Britzke 2003; A. Hicks,
pers. comm., 2004, 2005). However, maternity colonies of Indiana bats
have also been found in large forested blocks, even in predominantly
agricultural states such as Indiana. For example, at least five
maternity colonies are known on the Big Oaks National Wildlife Refuge,
where 88 percent of the land is classified as forest or forested
grassland (L. Pruitt, pers. comm., 2006).

Although most focus to date has been on the extent of wooded areas that
Indiana bats require, there are additional and possibly interrelated
factors that may contribute to where Indiana bats typically reproduce on
the continent. Climate likely plays an important role (Clark et al.
1987, Brack et al. 2002). As noted by Brack et al. (2002): "Areas of
higher latitudes and elevations typically are cooler and wetter, and
higher elevations experience greater seasonal variability, all of which
can reduce the food supply, increase thermoregulatory demands, and
reduce reproductive success of bats." Brack et al. (2002) suggested
climate as a potential explanation for why forest cover is generally not
predictive of the presence of Indiana bats, and why the species is more
abundant in portions of its range where forest cover is lower, at a
landscape scale. They noted: "The geographic association of good (i.e.,
warm) summer and good (i.e., cold) winter habitat is limiting for the
Indiana bat (*Myotis sodalis*)." They further explained that during
summer, the Indiana bat is most common in an area of the Midwest,
comprised of most of Indiana and Illinois, southern Iowa, southern
Michigan, the northern half of Missouri, and western Ohio. This area
accounts for more than 80 percent of known maternity colonies
(Service2004a). This portion of the species range is warmer in summer
than more heavily forested parts of the species range to the east and
northeast, where relatively higher latitudes and elevations typically
are cooler and wetter, and temperatures at higher elevations are more
variable, adding significantly to the cost of reproduction. Maternity
colonies in this portion of the range are more likely to be found at
lower elevations, where temperatures are more conducive to reproduction.
For example, the recently discovered colonies in the Lake Champlain
Valley occur in an area of fragmented forests relative to extensively
forested and higher elevation areas nearby in the Adirondack Mountains.
Harvey (2002) and Britzke et al. (2003) reported on the first documented
maternity colony in western North Carolina on the Nantahala National
Forest at an elevation of 1,158 m, the highest elevation reported for a
maternity colony of Indiana bats (Britzke et al. 2003). The colony was
originally located in 1999, and surveys at the site in 2000 failed to
document the presence of the bats. Maternity colonies were located the
same year in adjoining counties in eastern Tennessee in the Great Smoky
Mountains National Park (Harvey 2002, Britzke et al. 2003). These
colonies were found at elevations of 610 m and 670 m, and were
subsequently relocated in both 2000 and 2001.

Other potential factors that likely affect where Indiana bats reproduce
include distance from suitable hibernacula, competition for food with
other species of bats, and competition with other bats or birds for
roosting sites (Clark et al. 1987, Kurta and Foster 1995, Foster and
Kurta 1999, Murray and Kurta 2002, Sparks 2003).

In summary, most maternity colonies of Indiana bats that are known exist
in fragmented landscapes with low-to-moderate forest cover. However, it
is not clear whether the distribution of known colonies reflects a
preference for fragmented forests, a need for specific climates that
happen to occur where forests have been fragmented by humans, degree of
survey effort by biologists in different areas of the range, or some
other factor. Maternity colonies of Indiana bats have been found in
environments that vary considerably in amount of forest cover, and
further study is needed to determine whether survival or productivity
varies, positively or negatively, with the amount and type of forest
available and the degree of fragmentation that is present.

*Foraging Habitat*

Observations of light-tagged animals and bats marked with reflective
bands indicate that Indiana bats typically forage in closed to semi-open
forested habitats and forest edges (Humphrey et al. 1977, LaVal et al.
1977, Brack 1983). Radiotracking studies of adult males, adult females,
and juveniles consistently indicate that foraging occurs preferentially
in wooded areas, although type of forest varies with individual studies;
Indiana bats have been detected through telemetry using floodplain,
riparian, lowland, and upland forest (Garner and Gardner 1992; Hobson
and Holland 1995; Menzel et al. 2001; Butchkoski and Hassinger 2002;
Chenger 2003; Sparks 2003; Murray and Kurta 2004; Sparks et al. 2005a,
2005b). Indiana bats hunt primarily around, not within, the canopy of
trees, but they occasionally descend to subcanopy and shrub layers. In
riparian areas, Indiana bats primarily forage around and near riparian
and floodplain trees, as well as solitary trees and forest edges on the
floodplain (Cope et al. 1974, Humphrey et al. 1977, Belwood 1979, Clark
et al. 1987). Within floodplain forests where Indiana bats forage,
canopy closures range from 30 to 100 percent (Gardner et al. 1991a).

Nevertheless, Indiana bats have been caught, observed, and radiotracked
foraging in open habitats (Humphrey et al. 1977; Brack 1983; Clark et
al. 1987; Hobson and Holland 1995; Gumbert 2001; Sparks et al. 2005a,
2005b). In Indiana, individuals foraged most in habitats with large
foliage surfaces, including woodland edges and crowns of individual
trees (Brack 1983). Many woodland bat species forage most along edges,
an intermediate amount in openings, and least within forest interiors
(Grindal 1996).

Analyses of habitats used by radiotracked adult females while foraging
versus those habitats available for foraging have been performed in two
states. In Illinois, floodplain forest was the most preferred habitat,
followed by ponds, old fields, row crops, upland woods, and pastures
(Gardner et al. 1991b, Garner and Gardner 1992). In Indiana, woodlands
were used more often than areas of agriculture, low-density residential
housing, and open water, and this latter group of habitats was used more
than pastures, parkland, and heavily urbanized sites (Sparks 2003;
Sparks et al. 2005a, 2005b). Old fields and agricultural areas seemed
important in both studies, but bats likely were foraging most often
along forest-field edges, rather than in the interior of fields,
although errors inherent in determining the position of a rapidly moving
animal through telemetry made it impossible to verify this (Sparks et
al. 2005b). Nevertheless, visual observations suggest that foraging over
open fields or bodies of water, more than 50 m (150 ft) from a forest
edge, does occur, although less commonly than in forested sites or along
edges (Brack 1983, Menzel et al. 2001).

In autumn, Brack (2006) found that Indiana bats in Virginia were active
in nine habitats, and used open deciduous forests more than available,
and developed lands, closed deciduous habitats, and mixed
deciduous-evergreen habitats less than available. Agricultural lands,
intermediate deciduous forests, old fields, and water were used in
proportion to availability. Wooded pastures (agricultural) and recently
logged areas (open woodland) also provided foraging habitat. As the
autumn progressed, these bats included less agricultural habitat and
more deciduous forests (combined open, intermediate, and closed canopy)
in their activity areas. Relative abundance of insect prey in open,
exposed agricultural lands decreases with cooling temperatures and crop
harvest.

*Habitat Suitability Index Models*

Two habitat suitability index (HSI) models are available for maternity
sites of the Indiana bat in the Midwest, but neither has been
sufficiently validated. The model of Rommé et al. (1995) uses nine
variables, including two with sub-variables. The model provides output
to independently evaluate the quality of roosting and foraging habitat,
and provides an evaluation of overall summer habitat quality as affected
by two landscape-scale attributes.

The model of Farmer et al. (2002) distilled the model of Rommé et al.
(1995) down to only three variables, including number of habitat types
that contributed more than 10 percent of the surrounding area, density
of suitable roost trees, and percent of land in forest. Based on
mist-netting data previously gathered in Missouri by Miller (1996),
Farmer et al. (2002) concluded that only the density of suitable roost
trees was potentially useful in predicting whether Indiana bats were
present in a particular area. Farmer et al. (2002) were careful to point
out that sound empirical support was lacking for various components of
their model.

Carter (2005) recently used data collected in Illinois in a post-hoc
test of both models. Although he believed his study area should be
considered well above average (HSI of 0.8 to 0.9) in terms of quality of
habitat, the model of Rommé et al. (1995) resulted in a value of only
0.42. The model of Farmer et al. (2002), in contrast, indicated an HSI
of up to 0.8, suggesting that it might be more useful. Although such a
post-hoc test is suggestive, the value of these HSI models will remain
in doubt until they are validated through field studies that are
designed and implemented specifically to test the predictions of the
models at multiple sites. Carter (2005) noted that the HSI models assume
a circular home range, although bats frequently use linear landscape
elements (e.g., streams).

**Species Recovery**

The existing recovery program for the Indiana bat focuses on protection
of hibernacula (Service 1983). However, the Service is currently
revising the recovery plan for the species, and, based on the species'
population trends, threats, biological constraints, ongoing conservation
measures, and information needs, the future recovery program for this
species is anticipated to include four broad components: 1) rangewide
population monitoring at the hibernacula with improvements in census
techniques, 2) conservation and management of habitat (hibernacula,
swarming, and, to a degree, summer), 3) further research into the
requirements of and threats to the species, and 4) public education and
outreach. This anticipated approach may increase the focus on summer
(i.e., non-hibernation) habitat and proposes the use of Recovery Units.
This potential increased focus on summer habitat will likely be based on
the principles of conservation biology and research on the importance of
addressing both core and peripheral populations in conservation
strategies for rare species.

**Previous Incidental Take Authorizations**

Prior formal consultations involving the Indiana bat have involved a
variety of action agencies and project types. These have included:

(a) The Forest Service for activities implemented under various Land and
    Resource Management Plans on National Forests in the eastern United
    States;

(b) The Federal Highway Administration for various transportation
    projects;

(c) The U.S. Army Corps of Engineers (Corps), Tennessee Valley Authority
    (TVA) and West Virginia Department of Environmental Protection for
    various water-related and coal mining projects;

(d) The Department of Defense for operations at several different
    military installations; and

(e) The National Park Service for vegetation management and prescribed
    burn activities.

Additionally, an incidental take permit has been issued under section 10
of the ESA to an Interagency Taskforce for expansion and related
development at the Indianapolis Airport in conjunction with the
implementation of a Habitat Conservation Plan (i.e., Six Points Road
Interchange HCP).

A summary of the formal consultations completed over the past 10 years
is discussed below and provided in Appendix B. Formal consultations on
the Indiana bat completed prior to 1997 were omitted from this analysis.
This was done, because the incidental take provided prior to 1997 would
not be expected to affect the current environmental baseline for the
proposed action. This is due to several reasons, including:

> \(a\) The effects of the take occurred in the past and current
> population and other data are available that give us a better estimate
> of the environmental baseline;
>
> \(b\) The authorized take in many biological opinions has been
> superceded by new biological opinions; and
>
> \(c\) The relationship of the take in these older biological opinions
> and the applicability of such take to this biological opinion is
> tenuous, at best, because of the difficulty in drawing meaningful
> comparisons and conclusions for projects that may be geographically
> separated and not similar in their effects on the Indiana bat.

[]{.mark}

In conducting many of these consultations, Indiana bat presence/absence
survey information was unavailable, so the Service often relied on a
variety of factors to assist the action agency in determining if Indiana
bats could be present. For example, if survey information indicated that
Indiana bats were present in nearby areas, the action agency often
assumed that Indiana bats were present in the action area and could be
subject to incidental take. Further, if the best scientific and
commercial data available indicated that an Indiana bat maternity colony
could be present, a maternity colony was generally assumed to be present
within the action area. This type of conservative approach is generally
protective of Indiana bats because it tends to over-estimate the
incidental take that may occur. In most such cases, including the
proposed action, the Service analyzes the effect of the worst case for
incidental take on the proposed action but acknowledges that the worst
case is unlikely to occur. The fact that the worst case is unlikely to
occur is primarily due to implementation of project-related conservation
measures and other actions by the action agency to avoid and/or minimize
incidental take.

[]{.mark}

Previous consultations have addressed impacts to hibernating or swarming
bats, known maternity areas, or summer habitat that was assumed
occupied. Due to the various life stages affected, the types of
conservative assumptions made (as discussed above), and the difficultly
in documenting actual take to Indiana bats (as more fully described in
each biological opinion and the Incidental Take Statement section of
this biological opinion), different methods have been used to estimate
the amount of potential take. Depending on the consultation, take has
been measured either by estimating numbers of affected roost trees,
individual bats or maternity colonies, or acres of potentially suitable
and/or occupied habitat. However, the Service typically has determined
the incidental take measure that was used based on the most accurate and
reasonable means available for each site-specific analysis. For example,
Appendix B shows that biological opinions have exempted take of Indiana
bats on about 916,500 acres of potentially occupied habitat. However,
new information that became available after the issuance of some of the
biological opinions resulted in subsequent "not likely to adversely
affect" determinations for activities on about 517,600 acres of that
total acreage. Thus, only 398,900 acres of the original take acreage
exempted by these biological opinions remains authorized today.

[]{.mark}

In addition, over 81,000 acres of this 398,900-acre total has been
superceded by new biological opinions, which further reduces the total
take acreage to 317,900 acres range-wide (i.e., a very small proportion
of the species' range) and would result in potential double counting of
the affected acres if those acres were not subtracted from the total. A
good example of this relationship exists for the biological opinion for
the Northeast Research Station, where forest stands are harvested
multiple times over many years, with each entry being counted as a
separate acre of annual take (Service 2005c). Therefore, it is
difficult, for the reasons discussed previously in this section, to
measure the effects of previously authorized take without knowing the
details of each biological opinion and closely evaluating the outcome of
each consultation. Furthermore, even when we have the details of a
biological opinion and are able to evaluate the outcome, we may not be
able to draw realistic conclusions regarding the short- and/or long-term
effect of any incidental take that has occurred due to the difficulty in
monitoring and estimating incidental take of Indiana bats. []{.mark}

[]{.mark}

For example, several National Forests and one Forest Service Research
Station within the range of the Indiana bat have recently completed
consultation at the programmatic level. Consultation under section 7 of
the ESA is necessary to ensure Federal agency actions are not likely to
jeopardize the continued existence of listed species or result in the
destruction or modification of critical habitat of such species. The
Service concluded that the proposed Forest Plans were unlikely to
jeopardize the continued existence of the Indiana bat and issued
biological opinions with associated incidental take statements. Although
these incidental take statements anticipated the potential take of
reproductive females, we have not confirmed the loss of any maternity
colonies on a National Forest (NF).

[]{.mark}

The reasons for the lack of confirmed take of an Indiana bat maternity
colony are likely two-fold. First, notwithstanding the conservative
assumption that a maternity colony existed in the action area, to date,
only fourteen maternity colonies have been actually confirmed to exist
on the affected National Forests \[i.e., the Daniel Boone NF (7),
Hoosier NF (2), Mark Twain NF (1), Monongahela NF (1), Nantahala NF (1),
and Shawnee NF (2)\]. Surveys to identify and confirm other maternity
colonies on the DBNF and other National Forests are ongoing but are not
systematic. The National Forests covered by these biological opinions
generally conduct some form of Indiana bat population monitoring,
including mist net surveys, acoustical monitoring, and hibernacula
surveys, as appropriate. These surveys have served to document either:
the continued presence of Indiana bats on the forests; the discovery of
new maternity colonies on the subject forest; or the continued lack of
presence of Indiana bats even though the conservative assumption of
potential presence was made. Second, each Forest Plan includes
conservation measures (i.e., standards and guidelines) that are
protective of Indiana bats and their habitat and the reasonable and
prudent measures required by each biological opinion that are applicable
to each proposed action. These conservation measures and reasonable and
prudent measures are designed to protect all known or newly discovered
maternity colonies and to ensure an abundance of suitable Indiana bat
habitat on the National Forests.

Incidental take exempted on National Forests is typically monitored and
reported by acres of habitat lost, altered, or otherwise affected by a
covered project. Based on the anticipated levels of take provided in the
biological opinions for National Forest LRMPs, over 95 percent of these
acres are affected by varying degrees of temporary loss as a result of
timber management activities or prescribed burns (Service 2005a).
However, much of this incidental take is take that is assumed to occur
and based on a conservative assumption of take. Recording of actual
incidental take is difficult, if not impossible, in most situations due
to the difficulties in knowing if Indiana bats are actually present
within an affected area and whether they are actually harmed, harassed,
or killed. The Service or a federal action agency seldom has complete
information when initiating a proposed project that could adversely
affect Indiana bats and even more seldom is able to document that an
actual take has occurred (e.g., a dead Indiana bat is found after
implementation of the project).

[]{.mark}

In order to ensure that the anticipated level of take is not exceeded,
however, each National Forest provides annual reports of the actual
level of take that has been implemented. Although reported levels have
not been compiled for all the Forests, the actual incidental take used
has been less than the level exempted in the biological opinions for
many Forests. If incidental take is exceeded, re-initiation of
consultation is necessary.

A number of incidental take statements have also been issued to other
Federal agencies conducting activities that were determined not likely
to jeopardize the Indiana bat. Unlike the incidental take statements
issued for the National Forest Land and Resource Management Plans, some
of these other Federal agency actions were certain to impact known,
occupied habitat for Indiana bats. To minimize the effect of these
projects, the Federal action agencies agreed to implement various
conservation measures and to implement the reasonable and prudent
measures (if any) contained in the respective biological opinions for
those projects. Some of the measures implemented in these proposed
actions included: seasonal clearing restrictions to avoid disturbing
female Indiana bats and young; protection of all known primary and
alternate roost trees with appropriate buffers; retention of adequate
roosting and foraging habitat to sustain the maternity colony into the
future; and permanent protection of areas and habitat enhancement or
creation measures to provide future roosting and foraging habitat
opportunities.

With the exception of three (Fort Knox, Great Smoky Mountains National
Park, and Laxare East and Black Contour Coal Mining projects), none of
the biological opinions and associated incidental take statements issued
for non-Forest Plan activities anticipated the loss of a maternity
colony. The Fort Knox biological opinion \[1999\] exempted the take of
two potential maternity colonies and individual Indiana bats. However,
the biological opinion did not specify whether the \"take\" consisted of
loss of the colonies or take in the form of harm and harassment. Surveys
in 2004 and 2006 in the immediate area where the take was provided on
Fort Knox have shown that at least one maternity colony (and possibly
two) exists (M. Gumbert, Personal Communication, 2007). A concerted
effort is planned for 2007 to determine if the colony(ies) are indeed
the same colony(ies) known to use the area in 1999 by capturing females
banded in 1999. We have no data that tracks the take of maternity
colonies for the GSMNP biological opinion, but additional monitoring of
the maternity colony following the completion of the 2004 BO for the
Laxare East and Black Castle Contour projects, documented a colony much
larger than previously anticipated. Additional project modifications
subsequent to that discovery resulted in the retention of all known
roost trees and protection of some potential foraging areas.
Reinitiation of that consultation in 2006 concluded that while the
colony would experience adverse effects, the colony should be able to
persist through the life of the project.

Required monitoring for three additional consultations (Camp Atterbury,
Newport Military Installation, and Indianapolis Airport) has confirmed
that the affected colonies persisted through the life of the project and
continue to exist today. We recognize that given the philopatric nature
of Indiana bats and the long lifespan, the full extent of the
anticipated impacts may not yet have occurred. Nonetheless, these
monitoring results, and the lack of data to suggest otherwise, indicate
that the conservation measures to avoid and minimize the impacts of
Federal projects appear to be effective.

In summary, we believe the take exempted to date via section 7
consultation has resulted in temporary effects to Indiana bat habitat
and, in limited circumstances, Indiana bat maternity colonies. As many
of these consultations necessarily made conservative assumptions about
Indiana bat presence, we believe that the number of Indiana bats
actually exposed to the environmental impacts of the Federal actions is
less than anticipated. Furthermore, pre- and post-project implementation
monitoring of several maternity colonies preliminarily suggests that
proposed conservation measures, when employed in concert, appear to be
effective in minimizing adverse effects on the affected Indiana bats,
including maternity colonies, although this information cannot be
considered definitive.

For reasons stated above, and not withstanding that range-wide survey
results on a two-year interval indicate that the overall population of
Indiana bats is increasing, the Service concludes that the aggregate
effects of the activities and incidental take covered in previous
biological opinions on the Indiana bat have not degraded the overall
conservation status (i.e., environmental baseline) of the Indiana bat.

### 

### Analysis of the species/critical habitat to be affected

The Service has reviewed the BA and supporting information for the
proposed reconstruction of US 119. The BA evaluated the potential and
likely effects of the proposed highway construction project on the
Indiana bat, gray bat, and blackside dace. We concurred with the FHWA's
effects determination of "not likely to adversely affect" for two of the
three federally listed species (gray bat and blackside dace) addressed
by the BA. Our concurrence was provided in a separate letter dated
November 26, 2007 to the FHWA. These concurrences were based on: 1)
survey results determined that blackside dace did not occur in the
project area and majority of habitat proposed to be impacted are not
suitable to blackside dace, and 2) conservation measures would be
implemented to avoid and minimize significant impacts to occupied gray
bat foraging habitat. Critical habitat has not been designated for these
two species and, therefore, was not assessed. Thus, these two species
will not be considered further in this biological opinion

Based on FHWA's need to remove suitable Indiana bat forested habitat
throughout the spring staging and migration, summer roosting, maternity,
fall migration, and/or fall swarming periods of the Indiana bat, the
Service concurs with the FHWA's determination that the proposed project
may adversely affect the Indiana bat. Our concurrence is based on the
fact that construction of the proposed project during the aforementioned
periods could result in the harm, harassment, and/or mortality of
Indiana bats during construction activities and due to the direct loss,
alteration, fragmentation, or displacement of the Indiana bat's forested
habitat. Critical habitat has been designated for the Indiana bat, but
none of those critical habitat areas occur within the project area.
Therefore, the proposed project is not likely to adversely modify
critical habitat for the species, and the Indiana bat is the only
species that will be considered further in the remaining sections of
this biological opinion.

**ENVIRONMENTAL BASELINE**

Under section 7(a)(2) of the Act, when considering the "effects of the
action" on federally listed species, the Service is required to take
into consideration the environmental baseline. The environmental
baseline includes past and ongoing natural factors and the past and
present impacts of all Federal, State, or private actions and other
activities in the action area (50 CFR 402.02), including Federal actions
in the area that have already undergone section 7 consultation, and the
impacts of State or private actions that are contemporaneous with the
consultation in process. As such, the environmental baseline is "an
analysis of the effects of past and ongoing human and natural factors
leading to the current status of the species, its habitat (including
critical habitat), and ecosystem, within the action area (Service 1998,
page 4-22)." The environmental baseline is, therefore, a "snapshot" of
the species' health at a given point in time, but it does not include
the effects of the proposed action.

**Status of the species within the action area**

According to the known and suspected range of the Indiana bat (Service
1983), the Indiana bat ranges over an area of about 580,550 square miles
in the eastern one-half of the United States. The action area's surface
land area is approximately 420 square miles, which represents less than
one-tenth of one percent of the total range of the species. However, the
occupied range of the species within both the known range and the action
area is unknown but is likely to be considerably smaller than the known
range and action area, respectively, due to the presence of unsuitable
habitats within both of those areas and the lack of a uniform
distribution for the species. According to our records, the Indiana bat
is known from a number of locations within the action area, with
approximately 20 known capture locations focused primarily within the
area of Pine Mountain in Harlan and Letcher Counties. Some of the
records are from caves, which harbor Indiana bats each winter, but most
are summer records. Suitable roosting, foraging, and potential maternity
habitat for the Indiana bat occur throughout the action area. These
habitats likely support spring staging and migration, summer roosting,
maternity, fall migration, and/or fall swarming periods of Indiana bats
within the action area.

Although the action area does not contain any designated critical
habitat or any Priority I hibernacula (defined as harboring 30,000 or
more Indiana bats since 1960), it does contain 3 Priority II hibernacula
(harboring 500 to 30,000 bats). All three of the Priority II caves
(Crystal Cave, Line Fork Cave, and Green Cave) located within the action
area are on privately- or state-owned tracts of land on the north side
of Pine Mountain. Two of these hibernacula (Crystal Cave and Line Fork
Cave) are within 5 miles of the proposed project and Green Cave is
approximately 10 miles from the proposed project. No designated critical
habitat for the Indiana bat is located within the action area.

We have little specific information on the numbers of Indiana bats that
migrate outside of the action area, because few Indiana bats from the
entire range-wide population are captured, banded, or radiotracked each
year. However, survey efforts in the area of Pine Mountain, not
associated with the proposed action, captured an individual male Indiana
bat in the summer of 2006 from underneath a bridge on US 119 just a few
miles southwest of the project area. This bat was banded the night of
capture and in February 2007 the banded bat was recovered in Green Cave.
This recent occurrence and several other records of male Indiana bats
that were captured during summer near Pine Mountain hibernating in
hibernacula on Pine Mountain suggests that some individual bats remain
close to their hibernacula during the summer months. As a result, we
believe that it is reasonable to assume that other Indiana bats may use
summer habitats near their hibernacula that lie within the action area.
Therefore, we expect that other Indiana bats may remain within the
action area year-round utilizing both summer roosting habitat, swarming
habitat, and hibernacula within the Pine Mountain area.

Surveys conducted for the proposed project resulted in the capture of a
juvenile male Indiana bat prior to the time when juvenile male bats are
thought to migrate away from the maternity colony. Due to this capture,
it is reasonable to expect that at least one maternity colony is likely
to be utilizing the area surrounding the proposed project as both
roosting and foraging habitat where suitable habitat exists. However,
the exact number of individuals within this colony or the specific home
range of the colony was not determined by FHWA. If telemetry data had
been taken that identified the maternity and secondary roost trees of
this maternity colony and its foraging habitat, we would likely have
been able to eliminate a number of adverse effects. However, this data
was not available; therefore, we could not discount the potential
effects of the proposed action in this biological opinion. Further, we
do not believe that any maternity colonies will be lost due to the
proposed action based on information we have from a number of areas
showing that maternity colonies tend to persist in the face of even
significant disturbances (e.g., see Fort Knox biological opinion).

A number of land use and management activities occur within the action
area that may affect the Indiana bat. The most likely activities to
occur within this area include:

\(a\) timber harvest;

\(b\) off-highway vehicle (i.e., ATV) recreational use;

\(c\) recreational use of caves (i.e., potential adverse effect on
hibernacula);

\(d\) underground and surface mining; and

> \(e\) development associated with road, residential, industrial, and
> agricultural construction and related activities.

Long-term land use and demographic trends may also play a key role in
any effects that may occur to the Indiana bat if these trends result in
destruction and/or modification of Indiana bat habitat. Overall, we have
determined that the effects of these past and ongoing human and natural
factors leading to the status of the Indiana bat, its habitat, and
ecosystem, within the action area are both qualitative and quantitative
in nature and will be discussed further in the paragraphs that follow.

### Factors affecting the species' environment within the action area

In order to ensure the consideration of all potential direct, indirect,
and cumulative effects of the proposed action on the Indiana bat, the
Service determined that the action area under consideration will include
those areas within the right-of-way disturbance limits for the entire
project length, the described waste areas associated with the project,
and an area approximately 10 miles on either side of the pinnacle of
Pine Mountain within Letcher and Harlan Counties, Kentucky. Additional
description of the action area is provided in the "Description of the
Action Area" section above.

Numerous land use activities that affect the Indiana bat and that likely
occur within the action area including: timber harvest, ATV recreational
use, recreational use of caves, underground and surface coal mining, gas
production, and development associated with road, residential,
industrial, and agricultural development and related activities. These
private actions are likely to occur within the action area, but the
Service is unaware of any quantifiable information relating to the
extent of private timber harvests within the action area, the amount of
use of off-highway vehicles within the action area, or the amount of
recreational use of caves within the action area. Similarly, the Service
does not have any information on the amount or types of residential,
industrial, or agricultural development that have or will occur within
the action area. Therefore, the Service is unable to make any
determinations or conduct any meaningful analysis of how these actions
may or may not adversely and/or beneficially affect the Indiana bat. All
we can say is that it is possible that these activities, when they
occur, may have direct, indirect, and/or cumulative effects on Indiana
bats and their habitat in certain situations (e.g., A private timber
harvest during summer months within an unknown maternity colony may
cause adverse effects to that maternity colony.). In stating this,
however, we can only speculate as to the extent or severity of those
effects, if any.

The Service does, however, have information regarding the extent of
state and federal highway development projects (does not include county
or local government road projects) and underground and surface coal
mining within the action area. For highway projects, approximately fewer
than 5 minor highway projects have been proposed and/or implemented
within the action area since October 2002. KYTC either assumed that
suitable Indiana bat summer habitat existed in the project area or
conducted a separate BA documenting the absence of the bat within the
project areas for those projects. For the projects where BA's were not
conducted, we do not believe that adverse effects to Indiana bats
occurred on each project, because, in many cases, the habitat was
removed during the winter months when Indiana bats were not present.

It is anticipated that approximately twice as many projects could lie
wholly or partially within the action area and may be implemented over
the next six years. Most of these projects would be expected to result
in some removal of potential Indiana bat summer habitat. It is difficult
to determine the extent of summer habitat to be removed as most of these
future projects have not completed the design phase yet. However, this
does not take into account any avoidance or minimization measures that
may be implemented or any surveys that will be done to determine
presence/absence of the species. These factors would likely reduce or
may eliminate the probability of adverse effects occurring because of
these projects. This also does not take into account the fact that these
projects typically undergo an independent section 7 review and separate
informal or formal consultation, if necessary.

We are also unable to determine the acreage of any past or future
habitat losses from the road projects described above, because KYTC does
not keep such records. However, most of these projects are subject to
separate, independent section 7 consultations, because they typically
have a federal nexus (e.g., FHWA funding or a Clean Water Act section
404 permit from the U.S. Army Corps of Engineers). As a result, it is
unlikely that any adverse effects would result from these projects
without first undergoing the Service's review and consultation.

Surface and subsurface coal mining is evident within the action area and
particularly within and adjacent to the project area. Significant mining
has occurred on Black Mountain near the project corridor. Underground
mining, which would have only minor (i.e., typically less than 20 acres
per permit) surface impacts and may or may not involve the removal of
potential Indiana bat summer habitat, has and continues to occur within
and adjacent to the action area. There are several active underground
mines within or adjacent to the project corridor, and at least six
underground mines, designated as closed located to the south of the
project alignment. Surface (strip) coal mining would involve much larger
surface disturbances, which again may or may not involve the removal of
potential Indiana bat summer habitat. Several of the closed underground
mines near the project area have since been surfaced mined. The project
will run through the bases of two mining properties with mining
scheduled to occur in at least one section of the alignment before the
road is constructed.

The Service is provided an opportunity to review all Kentucky Department
of Natural Resources mining permit applications, and all such
applications and issued permits are subject to the 1996 Programmatic
Biological Opinion for Surface Coal Mining Regulatory Programs Under the
Surface Mining Control and Reclamation Act of 1977 (Public Law 95-87).
Therefore, any potential adverse effects that may result from coal
mining activities within the action area have been accounted for through
a separate formal consultation with the Service and, if adverse effects
are likely to occur, the subsequent implementation of an Indiana bat
protection and enhancement plan by the mining permittee to avoid and
minimize impacts to Indiana bats as required by the 1996 biological
opinion.

**EFFECTS OF THE ACTION**

This section includes an analysis of the direct and indirect effects of
the proposed action on the species and/or critical habitat and its
interrelated and interdependent activities. While analyzing direct and
indirect effects of the proposed action, the Service considered the
following factors:

[Proximity of the action]{.underline}: As stated in the environmental
baseline, the capture of a juvenile male Indiana bat prior to the time
when juvenile male bats are thought to migrate away from the maternity
colony provides the assumption that at least one maternity colony may
exist within or in close proximity to the proposed project. Life history
characteristics of the species show that maternity colonies typically
consist of more than one female and Indiana bats will occupy the
available foraging and roosting habitat surrounding the colony's primary
roost tree(s). Therefore, it is reasonable to assume that additional
females utilize the habitat within this maternity colony's home range
and that other primary and secondary roost trees are present with the
colony's home range.

The capture site for the juvenile male was situated within or directly
adjacent to the project right-of-way. Maternity roosts and foraging
ranges were not determined by the FHWA for this maternity colony.
However, research indicates recorded travel of up to 5.2 kilometers
(3.23 miles) between successive maternity roosts (Kurta et al., 2002)
and foraging ranges from roost trees have been recorded up to 8.37
kilometers (5.20 miles) (Sparks et al., in press), with the average
foraging ranges reported by Sparks et al. being 3.02 kilometers (1.88
miles). Based upon this data, we have determined that Indiana bats
associated with the maternity colony will utilize the proposed project
area within an average of a 2.5-mile radius from the project center line
and terminus.

Three of the Indiana bat hibernacula (Crystal Cave, Line Fork Cave, and
Green Cave) are located within the action area on the north side of Pine
Mountain. Two of these hibernacula (Crystal Cave and Line Fork Cave) are
within 3-5 miles of the proposed project and Green Cave is approximately
10 miles from the proposed project. No designated critical habitat for
the Indiana bat is located within the action area.

Suitable roosting, foraging, and potential maternity habitat for the
Indiana bat occur within and adjacent to the project area. These
habitats likely support spring staging and migration, summer roosting,
maternity, fall migration, and/or fall swarming periods of Indiana bats
within the project area. Indiana bats have been shown to utilize a
10-mile radius surrounding hibernacula for foraging and mating prior to
hibernating. Thus, the project area lies within the foraging distance
for three hibernacula and much of the potential habitat within this area
would likely serve as swarming habitat for these hibernacula.

[Distribution]{.underline}: The project will have direct effects on the
species within the construction disturbance limits including associated
waste areas. Indirect effects on the species may also occur as a result
of the project throughout all or some of the remainder of the action
area defined previously due to fragmentation, alteration of maternity,
foraging, and swarming habitats, alterations to individual bat behavior
patterns, and modifications of population dynamics in the action area.

[Timing]{.underline}: Removal or destruction of habitat during the
spring staging and migration, summer roosting, maternity, fall
migration, and/or fall swarming periods of the Indiana bat would cause
the removal of habitat during a time that the species need and/or use
the habitat. Potential direct adverse affects could be minimized if all
or some of this habitat is removed during time periods when the species
is not likely present (i.e., hibernation). However, Indiana bats have
been shown to show some site affinity to their roosting trees, so, if
these trees are removed while the bats are not present, this is
anticipated to cause a modification in the behavior of any bats that
return to those areas. This could also cause those bats to use
additional energy to locate a new roost, which may affect reproductive
success.

[Nature of the effect]{.underline}: It is likely that the proposed
project will have a variety of effects on individual Indiana bats and
the associated maternity colony. In particular, the proposed project
activities are expected to (a) eliminate occupied and potential foraging
and roosting habitat through removal and/or conversion of that habitat
(e.g., removal of maternity roost trees, summer roost trees, and
foraging habitat); (b) alteration of habitat (e.g., fragmentation of
foraging habitat, modification of travel corridors; (c) alteration
and/or modification of normal Indiana bat behaviors (e.g., reproduction
effects, foraging effects, and sheltering behaviors); and (d)
potentially cause the mortality and/or injury of individual bats.

[Duration]{.underline}: The proposed action will cause the permanent
destruction, alteration, and fragmentation of the available habitat for
Indiana bats utilizing these forested areas throughout various needed
times of the year.

[Disturbance frequency]{.underline}: The disturbance will be a one-time
disturbance that will likely be sustained over one to three spring
staging and migration, summer roosting, maternity, fall migration,
and/or fall swarming periods while the proposed project is being
constructed. After completion of the construction, the disturbance will
be continuous, because the habitat will be lost permanently and the US
119 corridor will be under constant use, which may cause Indiana bats to
modify their normal behavior patterns.

[Disturbance intensity]{.underline}: The intensity of the disturbance is
difficult to estimate, because we do not know how much of the habitat
being removed is occupied and the density of Indiana bats utilizing
these areas. However, a majority of the area adjacent to and surrounding
the project area is forested and maintains similar characteristics of
the habitat being removed. While the proposed project will result in
some incidental take of Indiana bats, previous discussions indicate the
likelihood that bats will adjust to construction activities and habitat
removal and occupy similar habitats within the action area without
significant reductions in population size.

[Disturbance severity]{.underline}: The species' resiliency to natural
and anthropogenic disturbances has been demonstrated through monitoring
(See Previous Incidental Take Authorizations and Status of the Species
in the Action Area sections above). While the proposed project will
result in some incidental take of Indiana bats, previous discussions
indicate the likelihood that bats will adjust to construction activities
and habitat removal and occupy similar habitats within the action area
without appreciably reducing the species ability to recover. Also, the
severity will vary based on the timing of the disturbances and whether
or not Indiana bats occupy the habitat at the time the disturbance
occurs.

**Analyses for effects of the action**

[Beneficial effects]{.underline}

Beneficial effects are those effects of an action that are wholly
positive, without any adverse effect, on a listed species or designated
critical habitat. The only beneficial effect that we can determine is
the probable creation of an unknown number of potential roost trees that
would result from construction activities near the periphery of the
construction limits for the proposed project. However, this effect is
not wholly positive (i.e., it will be the by-product of disturbances
that may cause adverse effects).

[Direct Effects]{.underline}:

Regardless of time period (spring staging and migration, summer
roosting, maternity, fall migration, and/or fall swarming periods) when
the project construction is being conducted, it is likely that the
project will have a variety of effects on individual Indiana bats and
the associated maternity colony. Due to the nature of the project,
effects are not solely limited to the period of construction, but become
permanent and ongoing with operation of the road. The extent of take
will depend on the location and timing of impacts to foraging and
roosting habitat in relation to the distribution and density of Indiana
bats occupying these habitats at any given time.

During the summer roosting (i.e., non-hibernation) season Indiana bats
often roost in live, damaged, and/or dead trees with or without
naturally exfoliating bark. The presence of these trees, especially
those of high quality (e.g., large with exfoliating bark), within a
maternity colony's home range is important, because females group
together to give birth and rear their young until the juveniles become
volant (i.e., capable of flying) in these trees. The removal of
approximately 456 acres of potential Indiana bat foraging and/or
roosting habitat has the potential to cause direct adverse effects on
Indiana bats by altering their necessary summer habitat characteristics.
These clearing activities may involve the removal of occupied roost
trees and/or the modification of occupied foraging habitat where
proposed harvests and summer home ranges of Indiana bats within the
action area overlap. These effects will be permanent when it is
converted to roadway pavement and associated cut and fill slopes. We
expect that this conversion will directly affect Indiana bats and result
in take of bats in the form of harm or harassment for all Indiana bats
that had depended upon this habitat for use as spring staging and
migration, summer roosting, maternity, fall migration, and/or fall
swarming periods.

Blasting and construction activities are not anticipated to have any
direct effects on Indiana bats hibernating and/or the hibernacula within
the action area due to the fact that the closest point of the project is
at least three miles from the closest hibernacula, and all three
hibernacula are on the opposite side of Pine Mountain from the project.
However, these activities during the non-hibernation season could
directly affect Indiana bats and may kill bats roosting in proximity to
the disturbance, but we believe that this is unlikely because other
disturbances prior to blasting (e.g., removal of forested habitat prior
to blasting) will result in adverse effects first. Blasting may cause
sufficient disturbance to force any roosting bats, including any
maternity colony present, to find an alternate roost, and may force the
bats to abandon a roost in the area. Relocation to less suitable habitat
may be a repeated occurrence on subsequent nights until that stage of
construction is complete. This is expected to harm and harass all
Indiana bats roosting near blasting and construction, potentially
resulting in lower reproductive success, reduced vigor, and reduced
individual survival.

Another direct effect that may occur is the disturbance of a roosting
bat that causes the bat to flush from the roost tree during daylight or
otherwise modify its normal behavior. This type of adverse effect could
result from any of the activities mentioned previously. The noise and
vibration generated from construction activities and equipment will
likely occur during daylight hours and at variable distances from
occupied roost trees. The novelty and intensity of these perturbations
will likely dictate the range of Indiana bat responses to them. For
instance, Indiana bats roosting at some distance from the construction
may initially be startled by unusual noises in the distance but may
habituate to the noises if they are of low volume and a distance is
maintained between the roost and the disturbance. At closer distances
and increasing noise or vibration levels, Indiana bats may be startled
to the point of fleeing from their roosts, which may increase the risks
of injury, mortality, predation, abandonment of non-volant young, and
other adverse effects. Non-volant young that are abandoned permanently
are unlikely to survive.

Alternatively, Indiana bats that roost within or close to construction
areas will likely be subjected to increased levels of disturbance
frequency and intensity. As a result, Indiana bats displaced by
construction activities may be forced to use different roost trees.
These roost trees may be more or less suitable (e.g., easily accessed by
predators) than the roosts they were displaced from. Habitat conditions
surrounding the disturbance area will likely determine the quality of
any alternative roosts that are used.

We also anticipate that Indiana bats may change roosting areas by
temporarily or permanently abandoning their current roosts and seeking
roosts that are further away from the active disturbance area. This has
been supported by a few accounts in the literature. For example,
Callahan (1993) noted that the likely cause of the bats in his study
area abandoning a primary roost tree was disturbance from a bulldozer
clearing brush adjacent to the tree, and female bats in Illinois used
roosts at least 1640 ft (500 m) from paved roadways (Garner and Gardener
1992). While we do not know if Indiana bats will return to roosting
areas subjected to construction activities after the construction is
completed, research of other project action areas suggests that they
have done so in the past when appropriate measures where applied.

Conversely, some literature has reported that Indiana bats used roosts
close to significant disturbance. In one study near I-70 and the
Indianapolis Airport, a primary maternity roost was located 1,970 ft
(0.6 km) south of I-70. This primary maternity roost was not abandoned
despite constant noise from the Interstate and airport runways. However,
the roost's proximity to I-70 may be related to a general lack of
suitable roosting habitat in the vicinity and due to the fact that the
noise levels from the airport were not novel to the bats (i.e., the bats
had apparently habituated to the noise) (Service 2002). Therefore, we
cannot say definitively that Indiana bats will shift or abandon their
roosts as a result of the proposed construction actions.

We do not anticipate that construction activities will affect the
long-term availability of alternative roosting, foraging and/or fall
swarming habitat, because there is a surplus of potentially suitable
habitat within the action area. This surplus is based on the facts that
(a) forests cover the majority of the action area and (b) Indiana bats
do not occupy all available habitats within these areas. However, we
expect that these habitats surrounding the project area will be
modified. These modifications may temporarily degrade the available
foraging, and/or fall swarming habitat in situations where the project
is adjacent to habitat that is optimum, but this is expected to be a
minor, short-term effect.

So, even though potential adverse effects to Indiana bats during the
spring staging and migration, summer roosting, maternity, fall
migration, and/or fall swarming periods may occur when proposed
construction activities occur, the overall potential adverse effects
resulting from the project are reduced significantly because: (a) The
proposed action will not cause adverse effects in every situation.
Indiana bats do not roost in every potential roost tree within the
action area, so the removal of unoccupied trees and trees in unoccupied
habitat will be inconsequential. The available survey and life history
information for the species show that Indiana bats do not use all
potential roost trees within their home ranges. Therefore, Indiana bats
will use only a small proportion of the potential roost trees that would
be lost, which means that potential adverse effects will be limited; (b)
All but one of the approximate 20 known sites for the Indiana bat within
the action area and all three hibernacula records occur outside of the
disturbance limits of the project. In addition, summer site records are
well distributed across the Pine Mountain/ action area, which suggests
that potential adverse effects will be localized to only those bats
utilizing forested areas within the limits of the proposed project.

#### Interrelated and Interdependent Effects

#### An interrelated activity is an activity that is part of the proposed action and depends on the proposed action for its justification (Service and National Marine Fisheries Service \[NMFS\] 1998). An interdependent activity is an activity that has no independent utility apart from the action under consultation (Service and NMFS 1998). A determination of whether other activities are interrelated to, or interdependent with, the proposed action under consultation is made by applying a "but for" test. That is, it must be determined that the other activity under question would not occur "but for" the proposed action under consultation (Service and NMFS 1998). For example, private timber-harvesting or coal mining activities that occur outside the project area but within the action area would only be considered as interrelated or interdependent if a determination was made that these activities would not occur but for implementation of the proposed project. There is no justification for claiming that these actions would not occur "but for" the reconstruction of US 119 since both activities (timber and mining) have and continue to occur prior to the new road; and the new road is not designed to specifically service either action directly. Therefore, these actions outside the boundaries of the proposed project cannot be considered as an interrelated or interdependent action that should be considered in this biological opinion. Further, any unforeseen activity that may occur because of the proposed reconstruction of US 119 (e.g., additional access roads) would receive a project-specific analysis and subsequent section 7 consultation with the Service through the BA process.

###### [Indirect Effects]{.underline}

We had difficulty identifying indirect effects due to the nature of the
project and the fact that most effects of the action on the species
occur within and during occupied Indiana bat areas during construction
of the project. We would expect indirect effects on the Indiana bat to
occur when construction activities conducted during the (hibernating
period), resulted in the loss of suitable forested habitat areas
utilized by Indiana bats. Bats could be harmed or harassed due to the
removal of suitable roost trees and foraging habitat while the bats are
hibernating. This could lead to unexpected energy expenditures to find
new, suitable roosting areas when females return to maternity areas in
the early summer. In addition, placement of a new highway through
occupied Indiana bat habitat could result in harm of individuals that
attempt to cross the highway. However, it is unlikely that vehicle
collisions with bats could be monitored and/or documented accordingly to
determine what, if any, significance this potential effect may have on
the Indiana bat. However, these effects would likely occur after
construction of the proposed project.

**Species' response to a proposed action**

[Numbers of individuals/populations in the action area
affected]{.underline}

According to our records, the Indiana bat is known from a number of
locations within the action area, with approximately 20 known capture
locations within the action area. Three of the records are from caves,
which harbor anywhere from several hundred to several thousand Indiana
bats each winter. Approximately 19 known sites for the Indiana bat
within the action area and all three hibernacula records occur outside
of the disturbance limits of the project's construction actions that
were previously determined to have direct adverse affects on the Indiana
bat. In addition, these 19 summer site records are well distributed
across the Pine Mountain / action area, which suggests that potential
adverse effects will be localized to only those bats utilizing forested
areas within the limits of the proposed project (i.e., those bats
associated with one known capture record and an undetermined number of
migrating or fall swarming bats). Given the fact that the potential
adverse affects from the proposed action would be localized, we do not
expect the affects of the proposed action to impact a large number of
individuals. This is due to many reasons including, but not limited to,
(a) a surplus of potentially suitable habitat within the action area
because similar forested habitat covers a majority of the action area,
and (b) Indiana bats do not occupy all available habitats within these
impacted areas. Modifications may temporarily degrade the available
foraging, and/or fall swarming habitat in situations where the project
is adjacent to habitat that is optimum, but this is expected to be a
minor, short-term effect.

[Sensitivity to Change]{.underline} -- The Indiana bat does not appear
to be particularly sensitive to change within its summer and swarming
habitats (See Previous Incidental Take Authorizations and Status of the
Species in the Action Area sections above). Most Indiana bat maternity
colonies occur in disturbed landscapes and forest habitat areas of low
to moderate canopy cover, and a preponderance of the data on summer
roosting and foraging habitat show that Indiana bats appear to select
roost trees based on proximity to natural or anthropogenic disturbances.
Some examples of this include, among others, (a) the selection of
primary roost trees that are in canopy openings that will provide solar
exposure and radiant heat for maternity colonies, (b) the preferential
use of roost trees within various types of timber harvests in many
areas, and (c) the use of edges and tree corridors for travel and
foraging.

This is not true, however, for winter hibernation habitat. Indiana bats
appear to be particularly sensitive to changes in microclimatic
conditions within hibernacula and to disturbances during hibernation
(See Historic Abundance, Ecological Trap, and Hibernation Habitat
sections above), which are the primary reasons cited for the species'
historic population losses. There are no anticipated effects to any of
the hibernacula within the action area.

[Resilience]{.underline} - For the proposed action, the loss and
disturbances associated with the project's construction activities will
be relatively small and localized compared to the action area and the
species' range. The species' resiliency to natural and anthropogenic
disturbances has been demonstrated in a variety of contexts (See
Previous Incidental Take Authorizations and Status of the Species in the
Action Area sections above). In most cases of which we are aware,
Indiana bat maternity colonies have persisted after minor or significant
disturbances occurred, and the species (both males and females) have
shown a natural tendency to routinely shift roost trees and to take
advantage of new roosting and foraging opportunities (See above sections
that discuss summer roosting habitat). We do not believe that types of
disturbances associated with the proposed action (i.e., a relatively
small, linear, and localized impact compared to the action area and the
species' range) will significantly affect the species even though it has
a relatively low reproductive rate.

[Recovery Rate]{.underline} -- We expect the time required for
individual Indiana bats, the Indiana bat population with the action
area, and the affected Indiana bat habitat to return to equilibrium
after implementation of the proposed action to be negligible. Most
adverse effects associated with the proposed action are of temporary
and/or of short duration as discussed elsewhere in the Analyses for
Effects of the Action section. Longer-term effects tend to be localized
(i.e., within the construction/clearing zone) within the action area,
thus having an effect on a smaller percentage of bats known to occur
within the action area.

**CUMULATIVE EFFECTS**

Cumulative effects include the combined effects of any future State,
local, or private actions that are reasonably certain to occur within
the action area covered in this biological opinion. Future Federal
actions that are unrelated to the proposed action are not considered in
this section because they require separate consultation under section 7
of the Act. For example, many of the large-scale activities that could
occur in the action area, such as future highway development and mining,
would have a federal nexus that would require an independent
consultation under section 7 of the Act. As such, they would not be
included in this cumulative analysis.

The BA addresses a number of developments that currently exist along US
119 and the potential for cumulative impacts. Of the 7-mile project,
almost four miles of the length is bridges as high as 65 feet or rock
cuts as deep as 200 feet. While it is always possible that improvements
to infrastructure may allow for new growth, it is likely that design
elements of the new roadway in conjunction with topography would limit
access to land suitable for development. Given these factors and the
limited scale of anticipated development, it is unlikely that other
development associated with the reconstruction segment of US 119 would
have a significant adverse impact on the Indiana bat.

There is evidence that previous forestry-related activities have
occurred within the action area and may continue to occur. It is likely
that some of these forestry-related activities were associated with
other actions (e.g., previous road construction or mining operations) in
order to construct the project and would have had a federal nexus
requiring an independent consultation under section 7 of the Act.
However, the Service does not know of any specific forestry-related
actions in the action area that are reasonably certain to occur. The
action area is primarily forested, except for residences at the base of
Pine Mountain, existing infrastructure, and resource development. We do
not anticipate a significant change in forestry trends within Pine
Mountain and believe that much of the action area is expected to remain
forested, which will likely benefit the Indiana bat by retaining and/or
providing suitable habitat.

Because the Service is not aware of any future State, local, or private
actions that are reasonably certain to occur within the action area,
cumulative effects, as defined by the Act, will not occur and will not
be addressed further in this biological opinion.

**CONCLUSION**

After reviewing the current status of the Indiana bat; the environmental
baseline for the action area; the effects of the proposed reconstructed
of US 119; and cumulative effects of the proposed action, it is the
Service's biological opinion that implementation of the proposed action
and associated construction activities are not likely to jeopardize the
continued existence of the Indiana bat. Critical habitat for the Indiana
bat has been designated at a number of locations throughout its range;
however, this action does not affect any of those designated critical
habitat areas and no destruction or adverse modification of that
critical habitat is expected.

Because of our analysis, we do not believe that the proposed action
"would be expected, directly or indirectly, to reduce appreciably the
likelihood of both the survival and recovery of the Indiana bat by
reducing the reproduction, numbers, or distribution of the Indiana bat
(50 CFR 402)." For the proposed action to "reduce appreciably" the
Indiana bat's recovery, the proposed action would have to impede or stop
the process by which the Indiana bat's ecosystems are restored and/or
threats to Indiana bat are removed so that self-sustaining and
self-regulating populations can be supported as persistent members of
native biotic communities (Service and NMFS 1998, page 4-35). We do not
believe the proposed project impedes or stops the recovery process for
the Indiana bat because:

The species' resiliency to natural and anthropogenic disturbances has
been demonstrated (See Previous Incidental Take Authorizations). We
believe that the proposed roadway construction, while potentially
resulting in the incidental take of some individuals, are not a
significant threat to the species as a whole and, therefore, do not rise
to the level of jeopardy. No component of the proposed action is
expected to result in harm, harassment, or mortality at a level that
would reduce appreciably the reproduction, numbers, or distribution of
the Indiana bat.

The primary threats to the Indiana bat's recovery (Service 1983) are
destruction and alteration of species' winter hibernation habitat and
disturbance of Indiana bats while they occupy that winter habitat. The
proposed action does not result in any significant adverse effects on
Indiana bat hibernacula within the action area. Further, surveys were
conducted as part of the BA documenting the absence of and/or
discounting the suitability of other potential winter habitat within and
adjacent to the project corridor. The BA concluded that the proposed
project would not adversely affect any unclassified hibernacula.

For the proposed action to "reduce appreciably" the Indiana bat's
survival, the proposed action would have to impede or stop the condition
in which a species continues to exist into the future while retaining
the potential for recovery (Service and NMFS 1998, page 4-35). We do not
believe the proposed project impedes or stops the condition in which the
Indiana bat continues to exist while retaining the potential for
recovery, because any incidental take that may occur is typically not a
significant loss of individuals or a loss of habitat. For the proposed
action, the loss and disturbances associated with the project's
construction activities will be relatively small and localized compared
to the action area and the species' range. In most cases of which we are
aware, Indiana bat maternity colonies have persisted after minor or
significant disturbances occurred, and the species (both males and
females) have shown a natural tendency to routinely shift roost trees
and to take advantage of new roosting and foraging opportunities (See
above sections that discuss summer roosting habitat). We do not believe
that types of disturbances associated with the proposed action (i.e.,
relatively small and localized compared to the action area and the
species' range) will significantly affect the species.

For the reasons listed above and due to the fact that the species'
range-wide population numbers are increasing in spite of (a) the
previous incidental take that has been allowed and (b) an environmental
baseline that includes numerous activities that could result in adverse
effects to Indiana bats, we believe that neither the Indiana bat's
recovery nor its survival will be reduced appreciably by the adverse
affects associated with reconstruction of US 119. Where adverse effects
will actually occur, the species' ability to persist in the face of
these effects is well-documented.

##### 

##### INCIDENTAL TAKE STATEMENT

Section 9 of the Act and Federal regulations under section 4(d) of the
Act prohibit the taking of endangered and threatened species,
respectively, without special exemption. Take is defined as to harass,
harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or
attempt to engage in any such conduct. Harm is further defined by the
Service to include significant habitat modification or degradation that
results in death or injury to listed species by significantly impairing
essential behavioral patterns such as breeding, feeding, or sheltering.
Harass is defined by the Service as intentional or negligent actions
that create the likelihood of injury to listed species to such an extent
as to significantly disrupt normal behavior patterns that include, but
are not limited to, breeding, feeding, or sheltering. Incidental take is
defined as take that is incidental to, and not the purpose of, the
carrying out of an otherwise lawful activity. Under the terms of section
7(b)(4) and section 7(o)(2), taking that is incidental to and not
intended as part of the agency action is not considered to be prohibited
under the Act, provided that such taking is in compliance with the terms
and conditions of this Incidental Take Statement.

The measures described below are non-discretionary, and must be
undertaken by the FHWA so that they become binding conditions to the
KYTC, for the exemption in section 7(o)(2) to apply. The FHWA has a
continuing duty to regulate the activity covered by this Incidental Take
Statement. If the FHWA (A) fails to assume and implement the terms and
conditions or (B) fails to require the KYTC to adhere to the terms and
conditions of the Incidental Take Statement through enforceable
conditions, the protective coverage of section 7(o)(2) may lapse. In
order to monitor the impact of incidental take, the FHWA and/or KYTC
must report the progress of the action and its impact on the species to
the Service as specified in the Incidental Take Statement. 50 CFR
402.14(i)(3)

#### 

#### **AMOUNT OR EXTENT OF TAKE ANTICIPATED**

The Service anticipates incidental take of the Indiana bat will be
difficult to detect for the following reasons:

1.  The individuals are small and occupy summer habitats where they are
    difficult to find;

2.  Indiana bats form small (i.e., 25-100 individuals), widely dispersed
    maternity colonies under loose bark or in the cavities of trees, and
    males and non-reproductive females may roost individually which
    makes finding the species or occupied habitats difficult;

3.  Finding dead or injured specimens during or following project
    implementation is unlikely;

4.  The extent and density of the species within its summer habitat in
    the action area is unknown;

5.  Most incidental take will be non-lethal and undetectable.

However, incidental take of Indiana bats can be expected due to:

1.  Loss and alteration of occupied habitat associated with spring
    staging and migration, maternity, fall migration, summer foraging,
    and/or fall swarming periods (a direct effect);

2.  Loss and alteration of occupied travel corridor habitat (a direct
    effect);

3.  Harm and harassment of Indiana bats resulting from activities
    associated with the proposed project that will be conducted within
    and/or adjacent to occupied Indiana bat habitat between April 1 to
    October 15 (an indirect effect);

4.  Harm, harassment, or mortality associated with the loss,
    modification, and/or alteration of occupied habitat associated with
    spring staging and migration, maternity, fall migration, summer
    foraging, and/or fall swarming periods, and occupied travel corridor
    habitat resulting from the proposed project (a direct effect).

5.  Mortality associated with future traffic collisions (an indirect
    effect).

The level of take identified below may result, because the FHWA
anticipates that 456 acres of occupied and/or potential bat habitat
would be removed as a result of project implementation. Because of the
difficulty in determining a level of take based on the number of Indiana
bats that will be adversely affected, the Service has decided that it is
appropriate to base the level of authorized incidental take on the known
presence of Indiana bats in the vicinity and habitat acreage that will
be affected by the proposed project. Therefore, the level of take
authorized in this biological opinion is the 456 wooded acres of
occupied and/or potentially occupied Indiana bat habitat within the
construction limits of the proposed project, including the four waste
areas, as identified in the BA.

Incidental take of Indiana bats is expected to be in the form of harm
and harassment and is expected to occur as a result of construction
activities associated with the proposed project. "Harm", as defined
within the definition of "take" in the Act, means an act that actually
kills or injures wildlife. Such acts may include significant habitat
loss and/or alteration where the act actually kills or injures wildlife
by significantly impairing essential behavioral patterns, including
breeding, feeding or sheltering. "Harass", as defined within the
definition of "take" in the Act, means an intentional or negligent act
or omission which creates the likelihood of injury to wildlife by
annoying it to such an extent as to significantly disrupt normal
behavior patterns which include, but are not limited to, breeding,
feeding, or sheltering. Although mortality is the least likely form of
take to occur, adult or juvenile Indiana bats may be killed as a result
of removal of roosts trees and foraging habitat impairing natural
breeding, feeding or sheltering activities. Harm may also occur through
the habitat alterations that are anticipated to occur as a result of the
action which include, but are not limited to, removal of potential
summer roost trees, fragmentation and alteration of foraging and travel
corridor habitat, and removal of habitat utilized by Indiana bats during
spring staging and migration, maternity, fall migration, and/or fall
swarming periods. Harassment may also occur as a result of the indirect
effects outlined in previous sections of this biological opinion.
However, likely sources of harassment to Indiana bats include, but are
not limited to, noise and other disruptions (e.g., operations of
personnel and equipment) within occupied habitat.

#### **EFFECT OF THE TAKE** 

In the accompanying biological opinion, the Service determined that this
level of expected take is not likely to result in jeopardy to the
Indiana bat or destruction or adverse modification of critical habitat.

#### **REASONABLE AND PRUDENT MEASURES**

The Service believes the following reasonable and prudent measure(s) are
necessary and proper to minimize impacts of incidental take of the
Indiana bat:

1.  The FHWA will ensure that the proposed project components (e.g.,
    location and extent of the selected alternative and waste areas)
    will occur as planned and documented in the BA.

2.  The FHWA will ensure the preservation of suitable Indiana bat
    habitat and/or contribute to the Indiana Bat Conservation Fund
    (IBCF) to minimize the effect of the loss of occupied habitat on the
    Indiana bat.

3.  The FHWA must monitor its activities associated with the proposed
    project to determine if the Terms and Conditions of this biological
    opinion are being implemented adequately in order to ensure that
    take is minimized and provide an annual report of those activities
    to the Service.

### TERMS AND CONDITIONS

In order to be exempt from the prohibitions of section 9 of the Act, the
FHWA must comply with the following Terms and Conditions, which carry
out the Reasonable and Prudent Measures described above and outline
required reporting/monitoring requirements. These Terms and Conditions
are non-discretionary.

1.  The FHWA shall ensure that the location and extent of the proposed
    road alignment and associated waste areas is accomplished according
    to the plans reviewed under this biological opinion to minimize the
    amount of forest impacts. This Term and Condition is associated with
    Reasonable and Prudent Measure 1.

2.  The FHWA shall ensure that one or a combination (as stated within
    each option of this Term and Condition) of the following options is
    met within one year of the completion date of this biological
    opinion in order to minimize the effect of the loss of 456 acres of
    Indiana bat habitat. This Term and Condition is associated with
    Reasonable and Prudent Measure 2.

    a.  Option 1 - The FHWA shall protect one or both of known Indiana
        bat hibernacula (Green Cave and/or Crystal Cave) within the
        action area described within the "Action Area" section of this
        biological opinion. Protection of the cave(s) and cave
        entrance(s) shall also include a buffer of at least, but not
        limited to, 50 acres of surrounding forested habitat per cave
        that is directly adjacent and contiguous with the protected
        cave(s) entrance(s), unless otherwise agreed to by the Service
        in writing. If at least one hibernaculum is protected and a
        buffer totaling at least 456 acres of forested habitat is
        protected, then no further obligation under Term and Condition
        (TC) 2 is required. However, if one or both of the cave(s) are
        protected and a total of 456 acres of habitat cannot be
        protected as a forested buffer for the cave(s), then FHWA shall
        ensure that TC 2(b) (Option 2) or TC 2(c) (Option 3) is
        accomplished in combination with TC 2(a) (Option 1) for the
        difference of forested habitat protected. If TC 2(a) (Option 1)
        is not feasible, then FHWA shall ensure that TC 2(c) (Option 3)
        or TC 2(d) (Option 4) or combinations of each are met.

    b.  Option 2 - If the requirements of TC 2(a) (Option 1) are met but
        result in the protection of less than 456 acres of forested
        Indiana bat habitat as a buffer, then the FWHA shall make a
        contribution to the Indiana Bat Conservation Fund to make up the
        difference. To determine the amount of the contribution, the
        FHWA shall calculate the number of acres remaining by taking the
        difference of 456 acres and the acres of Indiana bat habitat
        protected through implementation of TC 2(a) (Option 1) and then
        multiply that number by 0.2 and the median agricultural land
        cost in Kentucky when this biological opinion was completed
        (currently \$2, 850 per acre). For example, if 100 acres remain,
        FHWA will use this formula: 100(0.2)(\$2850) = \$57,000 IBCF
        Contribution. This option may only be implemented in combination
        with TC 2(a) (Option 1).

    c.  Option 3 - If the requirements of TC 2(a) (Option 1) are not
        feasible or if the requirements of TC 2(a) (Option 1) and TC
        2(b) (Option 2) results in the protection of less than 456 acres
        of Indiana bat habitat, then the FHWA shall protect the
        equivalent of 456 acres of forested habitat within the action
        area. Habitat protected shall be (1) of equivalent or better
        quality than the forested habitat impacted; (2) no smaller than
        100 acre parcels unless agreed to by the Service in writing;
        and (3) contiguous with other existing potential Indiana bat
        forested habitat. Upon identification of such site(s), the FHWA
        will notify the Service for written approval of the site prior
        to protection. This option may be implemented solely or in
        combination with TC 2(a) (Option 1), TC 2(a) and (b) (Option 1
        and 2), or TC 2(d) (Option 4) for the difference of forested
        habitat protected.

    d.  Option 4 - If option TC 2(c) (Option 3) is not feasible or
        implemented in its entirety, then the FWHA shall contribute to
        the IBCF for all or the remainder of 456 acres of forested
        habitat not protected at a ratio of 1:1. To determine the amount
        of the contribution, the FHWA shall multiply the number of acres
        remaining by the median agricultural land cost in Kentucky when
        this biological opinion was completed (currently \$2, 850 per
        acre).

3.  The FHWA will submit no less than one summary report within nine
    months from the completion date of this biological opinion for the
    Service's review that describes the implementation or progress in
    meeting the requirements outlined in term and condition 2. The FHWA
    may request an extension, for the Service's consideration, to the
    time limitations in meeting the requirements outlined in term and
    condition 2. An extension request shall be provided to the Service
    in writing within one year from the completion date of this
    biological opinion and clearly identify the additional timeframe
    needed. This Term and Condition is associated with Reasonable and
    Prudent Measure 2.

4.  The FHWA will monitor the amount of wooded habitat removed each year
    of construction and cumulatively at the end of construction in order
    to ensure conformance to project plans and determine if the level of
    take afforded under this biological opinion (456 acres of habitat)
    is exceeded. The annual report shall include the table provided
    below. This Term and Condition is associated with Reasonable and
    Prudent Measure 3.

**Table X. Estimate of Indiana bat incidental take that occurred during
\[Insert Year Monitoring Was Conducted\] as a result of the
implementation of the \[Insert Name of Project\]**

[]{.mark}

+------------------------------------+----------------+----------------+
| ### Species                        | ### Habitat    |                |
+------------------------------------+----------------+----------------+
|                                    | Authorized     | Actual Level   |
|                                    | Level of       | of Habitat     |
|                                    | Habitat        | Alteration     |
|                                    | Alteration     |                |
+------------------------------------+----------------+----------------+
| Indiana bat -- Removal of Forest   | 456 acres      | \# of acres    |
| Habitat                            |                |                |
+------------------------------------+----------------+----------------+

The FHWA, KYTC, and/or its contractors must take care when handling dead
or injured Indiana bats or any other federally listed species that are
found in order to preserve biological material in the best possible
state and to protect the handler from exposure to diseases, such as
rabies. In conjunction with the preservation of any dead specimens, the
FHWA, KYTC, and/or its contractors have the responsibility to ensure
that evidence intrinsic to determining the cause of death or injury is
not unnecessarily disturbed. The reporting of dead or injured specimens
is required in all cases to enable the Service to determine if the level
of incidental take authorized by this biological opinion has been
reached or exceeded and to make sure that the terms and conditions are
appropriate and effective. Upon locating a dead, injured, or sick
specimen of any endangered or threatened species, prompt notification
must be made to the Service's Division of Law Enforcement at 1875
Century Blvd., Suite 380, Atlanta, Georgia 30345 (Telephone:
404/679-7057). Additional notification must be made to the Service's
Kentucky Ecological Services Field Office at 330 West Broadway, Room
265, Frankfort, Kentucky 40601 (Telephone: 502/695-0468).

The Reasonable and Prudent Measures, with their Terms and Conditions,
are designed to minimize the impact of incidental take that might
otherwise result from the proposed action. The Service believes that an
indeterminate number of Indiana bats will be incidentally taken as a
result of the proposed action with incidental take occurring on no more
than 456 acres of wooded habitat within the project area construction
limits including four waste areas. If, during the course of the action,
this level of incidental take is exceeded, such incidental take
represents new information requiring re-initiation of consultation and
review of the Reasonable and Prudent Measures provided. The FHWA must
immediately provide an explanation of the causes of the taking and
review with the Service the need for possible modification of the
Reasonable and Prudent Measures.

##### CONSERVATION RECOMMENDATIONS

Section 7(a)(1) of the Act directs Federal agencies to use their
authorities to further the purposes of the Act by carrying out
conservation programs for the benefit of endangered and threatened
species. The following conservation recommendations are discretionary
agency activities to minimize or avoid adverse effects of a proposed
action on listed species or critical habitat, to help carry out recovery
plans, or to develop information.

The Service provides the following Conservation Recommendations to the
FHWA:

> 1\. The FHWA should undertake or fund additional research, inventory,
> and monitoring work that is necessary to better understand the ecology
> of the Indiana bat. In particular, project areas should be selected
> and monitored for Indiana bat maternity roosting, foraging, and travel
> corridor habitat use, which will provide information to compare and
> evaluate the effects of future transportation activities on Indiana
> bat habitat.

2.  The demolition or removal of manmade structures (e.g. bridges) that
    harbor bats should occur while bats are hibernating elsewhere. If
    public safety is threatened and the structure must be removed while
    bats are present, a bat expert should examine the structure to
    determine if Indiana bats are present. Consultation with the Service
    should be initiated if Indiana bats are found.

In order for the Service to be kept informed of actions minimizing or
avoiding adverse effects or benefiting listed species or their habitats,
the Service requests notification of the conservation recommendations
carried out.

##### 

##### 

##### 

##### 

##### REINITIATION NOTICE

This concludes formal consultation on the reconstruction of US 119 from
Partridge to Oven Fork in Letcher County, Kentucky, and its effects on
the Indiana bat, as outlined in the July 16, 2007 FHWA request for
formal consultation. As stated in 50 CFR 402.16, re-initiation of formal
consultation is required where discretionary FHWA involvement or control
over the action has been retained (or is authorized by law) and if: (A)
the amount or extent of incidental take is exceeded, (B) new information
reveals effects of the FHWA's action that may affect listed species or
critical habitat in a manner or to an extent not considered in this
consultation (e.g., range-wide monitoring shows, over a five-year
period, a decline in hibernating Indiana bats), (C) the FHWA's action is
later modified in a manner that causes an effect to the listed species
or critical habitat not considered in this consultation, or (D) a new
species is listed or critical habitat is designated that may be affected
by the action. In instances where the amount or extent of incidental
take is exceeded, any operations causing such take must cease until
re-initiation.

For this biological opinion, the authorized incidental take would be
exceeded when the take exceeds 456 acres of occupied and/or potential
Indiana bat forest habitat, as described in this document, which is the
amount of take that has been exempted from the prohibitions of section 9
of the Act by this biological opinion.

The Service appreciates the cooperation of the FHWA and KYTC during this
consultation. For further coordination, please contact Mr. Phil DeGarmo
of this office at the address listed above or at (502) 695-0468 x110.
This consultation was assigned Project No. FWS 2007-B-1102; please refer
to this number in any correspondence concerning this consultation.

Sincerely,

Virgil Lee Andrews, Jr.

Field Supervisor

cc: Mr. Anthony Goodman, FHWA, Frankfort, KY

Mr. David Waldner, KYTC, Frankfort, KY

Regional Director, FWS, Atlanta, GA (Mr. Ken Graham)

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APPENDIX A

[]{.mark}

**Project Location and Action Area Map**

######## ![](media/image13.jpeg){width="5.580555555555556in" height="7.295833333333333in"} 

######## APPENDIX B

Indiana bat biological opinions including amount and form of incidental
take exempted.

+--------------------+--------------+------------+-------------------+
| **PROJECTS**       | **SERVICE    | **         | **TAKE EXEMPTED   |
|                    | OFFICE AND   | INCIDENTAL | or SURROGATE      |
|                    | DATE BO      | TAKE (IT)  | MEASURE TO        |
|                    | ISSUED**     | FORM**     | MONITOR**         |
+====================+==============+============+===================+
| 1996 Programmatic  | Washington   | IT by      | Unquantifiable    |
| Biological Opinion | DC           | harm,      |                   |
| for Surface Coal   |              | h          |                   |
| Mining Regulatory  | October 1996 | arassment, |                   |
| Programs Under the |              | and        |                   |
| Surface Mining     |              | killing of |                   |
| Control and        |              | all        |                   |
| Reclamation Act of |              | current    |                   |
| 1977 (Public Law   |              | and future |                   |
| 95-87)             |              | listed     |                   |
|                    |              | species    |                   |
+--------------------+--------------+------------+-------------------+
| Cherokee National  | Tennessee FO | IT by      | 1,300 acres       |
| Forest LRMP; Note: |              | killing    |                   |
| As a result of new | January 1997 | harming or |                   |
| information, this  |              | harassing  |                   |
| Forest is now      |              |            |                   |
| operating under a  |              |            |                   |
| "not likely to     |              |            |                   |
| adversely affect"  |              |            |                   |
| determination, and |              |            |                   |
| this BO is no      |              |            |                   |
| longer in effect.  |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Relocation of US   | Missouri FO  | IT by      | 56 hibernating    |
| Army Chemical      |              | harming,   | bats from fog oil |
| School & US        |              | harassing, | and TPA smoke     |
| Military Police    |              | or killing | pots; summer bats |
| School to Fort     |              |            | difficult to      |
| Leonard Wood,      |              |            | determine         |
| Missouri           |              |            | sub­lethal take    |
+--------------------+--------------+------------+-------------------+
| Daniel Boone       | Tennessee FO | IT by      | 4,500 acres       |
| National Forest    |              | killing,   |                   |
| LRMP; Note: This   | April 1997   | harming,   |                   |
| BO has been        |              | or         |                   |
| superceded by a    |              | harassing  |                   |
| March 2004 BO.     |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Ozark-St. Francis  | Arkansas FO  | IT by      | Annually 8,000    |
| National Forest    |              | killing,   | acres of timber   |
| LRMP; Note: As a   | June 25,     | harming or | harvest in        |
| result of new      | 1998         | harassing  | hardwoods, 11,000 |
| information, this  |              |            | acres harvest of  |
| Forest is now      |              |            | pine and          |
| operating under a  |              |            | pine/hardwoods;   |
| "not likely to     |              |            | 30,000 acres of   |
| adversely affect"  |              |            | prescribed        |
| determination, and |              |            | burning           |
| this BO is no      |              |            |                   |
| longer in effect.  |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Construction of    | Tennessee FO | IT by      | 2,000 acres       |
| New Training       |              | killing,   |                   |
| Facilities at Fort | October 1998 | harming or |                   |
| Knox, KY           |              | harassing  |                   |
+--------------------+--------------+------------+-------------------+
| Construction of a  | Tennessee FO | IT by      | 80 acres          |
| Qualification      |              | killing,   |                   |
| Training Range at  | October 1998 | harming or |                   |
| Fort Knox, KY      |              | harassing  |                   |
+--------------------+--------------+------------+-------------------+
| Construction &     | Indiana FO   | IT by harm | 1 maternity       |
| operation of the   |              | through    | colony (200 bats  |
| Multi-purpose      | December 4,  | habitat    | total) and 99.7   |
| training Range at  | 1998         | loss and   | ha of forest      |
| the Camp Atterbury |              | exposure   |                   |
| Army National      |              | to toxic   |                   |
| Guard Training     |              | agents     |                   |
| Site- Edinburgh    |              |            |                   |
| Indiana            |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Disposition of     | Tennessee FO | No take    | No take provided  |
| Lands Acquired by  |              | provided   |                   |
| the Tennessee      | March 1999   |            |                   |
| Valley Authority   |              |            |                   |
| for the Columbia   |              |            |                   |
| Dam Project, Maury |              |            |                   |
| County, Tennessee  |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Proposed stream    | Tennessee FO | IT by loss | 1800 acres; 2     |
| bank stabilization |              | of summer  | maternity         |
| at Yano Range and  | April 1999   | roosting,  | colonies          |
| upgrade of the     |              | foraging,  |                   |
| Wilcox Tank Range  |              | and        |                   |
| at Fort Knox, KY   |              | maternity  |                   |
|                    |              | habitat    |                   |
+--------------------+--------------+------------+-------------------+
| Agricultural       | Indiana FO   | IT by harm | 2 maternity       |
| Pesticide          |              | through    | colonies with 74  |
| Application        | April 13,    | exposure   | bats total        |
| Practices at       | 1999         | to         |                   |
| Newport Chemical   |              | pesticides |                   |
| Depot, Newport IN  |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Ouachita National  | Arkansas FO  | IT by      | 40,000 acres      |
| Forest LRMP; Note: |              | killing,   | commercial        |
| As a result of new | April 26,    | harming or | harvest; 3,000    |
| information, this  | 1999         | harassing  | acres wildlife    |
| Forest is now      |              |            | management & road |
| operating under a  |              |            | constructio       |
| "not likely to     |              |            | n/reconstruction; |
| adversely affect"  |              |            | 24,000 acres      |
| determination, and |              |            | thinning; 200,000 |
| this BO is no      |              |            | acres prescribed  |
| longer in effect.  |              |            | burning           |
+--------------------+--------------+------------+-------------------+
| Mark Twain         | Missouri FO  | IT by      | Timber harvest -- |
| National Forest    |              | killing,   | 20,000 acres per  |
| LRMP; Note: This   | June 23,     | harming,   | year; Prescribed  |
| BO has been        | 1999         | or         | fire - 12,000     |
| superceded by the  |              | harassing  | acres/yr;         |
| September 2005 BO  |              |            | Wildlife habitat  |
|                    |              |            | improvement -2000 |
|                    |              |            | acres/yr; Timber  |
|                    |              |            | stand improvement |
|                    |              |            | -- 4000 acres/yr; |
|                    |              |            | Soil & water      |
|                    |              |            | improvement --    |
|                    |              |            | 150 acres/yr;     |
|                    |              |            | Range management  |
|                    |              |            | -- 50 acres/yr;   |
|                    |              |            | Mineral           |
|                    |              |            | exploration &     |
|                    |              |            | development -- 50 |
|                    |              |            | acres/yr;         |
|                    |              |            | Wildfire fire     |
|                    |              |            | lines -- 50       |
|                    |              |            | acres/yr; Special |
|                    |              |            | use -- 50         |
|                    |              |            | acres/yr; Road    |
|                    |              |            | construction --   |
|                    |              |            | 25 acres/yr       |
+--------------------+--------------+------------+-------------------+
| Impacts of Forest  | Pennsylvania | IT by      | Within a 5-year   |
| Management and     | FO           | killing,   | period (1999 to   |
| Other Activities   |              | harming,   | 2003), the        |
| to the Bald Eagle, | June 1999    | or         | disturbance of    |
| Indiana Bat,       |              | harassing  | 45,594 acres      |
| Clubshell and      |              |            |                   |
| Northern           |              |            |                   |
| Riffleshell on the |              |            |                   |
| Allegheny National |              |            |                   |
| Forest,            |              |            |                   |
| Pennsylvania;      |              |            |                   |
| Note: As a result  |              |            |                   |
| of new             |              |            |                   |
| information, this  |              |            |                   |
| Forest is now      |              |            |                   |
| operating under a  |              |            |                   |
| "not likely to     |              |            |                   |
| adversely affect"  |              |            |                   |
| determination, and |              |            |                   |
| this BO is no      |              |            |                   |
| longer in effect.  |              |            |                   |
+--------------------+--------------+------------+-------------------+
| National Forests   | Alabama FO   | IT by      | No more than 100  |
| in Alabama; Note:  |              | killing,   | trees             |
| As a result of new | December 10, | harming or |                   |
| information, this  | 1999         | harassing  |                   |
| Forest is now      |              |            |                   |
| operating under a  |              |            |                   |
| "not likely to     |              |            |                   |
| adversely affect"  |              |            |                   |
| determination, and |              |            |                   |
| this BO is no      |              |            |                   |
| longer in effect.  |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Supplement for     | Tennessee FO | IT by      | No more than 20%  |
| Proposed Bridges & |              | killing,   | of available      |
| Alignments         | January 2000 | harming or | suitable habitat  |
| Modifications to   |              | harassing  |                   |
| Kentucky Lock      |              |            |                   |
| Addition Project   |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Green Mountain     | New England  | IT by      | 300 acres         |
| National Forest    | FO           | harming or |                   |
| LRMP; Note: As a   |              | harassing  |                   |
| result of new      | 2000         |            |                   |
| information, this  |              |            |                   |
| Forest is now      |              |            |                   |
| operating under a  |              |            |                   |
| "not likely to     |              |            |                   |
| adversely affect"  |              |            |                   |
| determination, and |              |            |                   |
| this BO is no      |              |            |                   |
| longer in effect.  |              |            |                   |
+--------------------+--------------+------------+-------------------+
| White Mountain     | New England  | IT by      | 1,500 acres       |
| National Forest    | FO           | farming or |                   |
| LRMP; Note: As a   |              | harassing  |                   |
| result of new      | 2000         |            |                   |
| information, this  |              |            |                   |
| Forest is now      |              |            |                   |
| operating under a  |              |            |                   |
| "not likely to     |              |            |                   |
| adversely affect"  |              |            |                   |
| determination, and |              |            |                   |
| this BO is no      |              |            |                   |
| longer in effect.  |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Nantahala and      | Asheville    | IT by      | 4,574 acres per   |
| Pisgah National    | (NC) FO      | killing,   | year              |
| Forests LRMP       |              | harming,   |                   |
| Amendment #5       | 2000         | or         |                   |
|                    |              | harassing  |                   |
+--------------------+--------------+------------+-------------------+
| Daniel Boone       | Tennessee FO | No take    | No take provided  |
| National Forest    |              | provided   |                   |
| LRMP and the       | May 2000     |            |                   |
| Proposed Special   |              |            |                   |
| Habitat Needs and  |              |            |                   |
| Silviculture       |              |            |                   |
| Amendment          |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Hazard Tree        | Tennessee FO | IT by loss | No take provided  |
| Removal and        |              | of         |                   |
| Vegetation         | June 2000    | roosting   |                   |
| Management Program |              | habitat,   |                   |
| at Mammoth Cave    |              | direct     |                   |
| National Park      |              | mortality  |                   |
|                    |              | or by      |                   |
|                    |              | forcing    |                   |
|                    |              | bats to    |                   |
|                    |              | abandon    |                   |
|                    |              | tree       |                   |
+--------------------+--------------+------------+-------------------+
| Salvage Harvest    | Tennessee FO | IT by      | 3,100 acres       |
| Necessitated by    |              | killing,   |                   |
| 1998 Storm Damage  | July 2000    | harming,   |                   |
| on the Daniel      |              | or         |                   |
| Boone National     |              | harassing  |                   |
| Forest             |              |            |                   |
+--------------------+--------------+------------+-------------------+
| North East         | West         | IT by      | 210 acres timber  |
| research Station   | Virginia FO  | potential  | harvest and 154   |
| -- Fernow          |              | harm or    | acres prescribed  |
| Experimental       | November     | mortality  | burn              |
| Forest -- Five     | 2000         | of         |                   |
| year plan          |              | roosting   |                   |
|                    |              | bats       |                   |
+--------------------+--------------+------------+-------------------+
| National Forests   | Alabama FO   | IT by      | Level of take     |
| in Alabama         |              | killing,   | changed for       |
| Re­initiation;      | January 23,  | harming or | southern pine     |
| Note: As a result  | 2001         | harassing  | beetle            |
| of new             |              |            | suppression areas |
| information, this  |              |            | -- upper limit of |
| Forest is now      |              |            | 65 suitable roost |
| operating under a  |              |            | trees             |
| "not likely to     |              |            |                   |
| adversely affect"  |              |            |                   |
| determination, and |              |            |                   |
| this BO is no      |              |            |                   |
| longer in effect.  |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Hoosier National   | Indiana FO   | IT by harm | Pine clear cuts   |
| Forest LRMP; Note: |              |            | -- 578 acres;     |
| This BO has been   | June 13,     |            | Pine shelterwood  |
| superceded by a    | 2001         |            | cuts -- 391       |
| January 2006 BO.   |              |            | acres; Pine       |
|                    |              |            | thinning -- 408   |
|                    |              |            | acres; Hardwood   |
|                    |              |            | group selection   |
|                    |              |            | cuts -- 777       |
|                    |              |            | acres; HW single  |
|                    |              |            | tree selection    |
|                    |              |            | cuts -- 100       |
|                    |              |            | acres; HW even    |
|                    |              |            | aged salvage cuts |
|                    |              |            | -- 518 acres;     |
|                    |              |            | Prescribed fire   |
|                    |              |            | treatment -- 7000 |
|                    |              |            | acres; Forest     |
|                    |              |            | openings          |
|                    |              |            | maintenance --    |
|                    |              |            | 3311 acres;       |
|                    |              |            | Timber stand      |
|                    |              |            | improvement --    |
|                    |              |            | 2264 acres;       |
|                    |              |            | Special use       |
|                    |              |            | permits -- 286    |
|                    |              |            | acres; Wildfire   |
|                    |              |            | management -- 250 |
|                    |              |            | acres; road       |
|                    |              |            | construction --   |
|                    |              |            | 16 acres; hazard  |
|                    |              |            | tree removal --   |
|                    |              |            | 100 trees; trail  |
|                    |              |            | construction --   |
|                    |              |            | 15 miles          |
+--------------------+--------------+------------+-------------------+
| Wayne National     | Ohio FO      | IT by harm | Permanent loss of |
| Forest LRMP; Note: |              |            | habitat -- 2,504  |
| BO has been        | September    |            | acres; Habitat    |
| superceded by a    | 20, 2001     |            | alteration --     |
| November 2005 BO.  |              |            | 8,102 acres plus  |
|                    |              |            | 125 trees         |
+--------------------+--------------+------------+-------------------+
| Ozark-St. Francis  | Arkansas FO  | IT by loss | Prescribed fire - |
| National Forest    |              | of roost   | 153,000 acres/yr  |
| Prescribed Fire    | March 21,    | trees and  |                   |
| Plan (an amendment | 2002         | potential  |                   |
| to June 1998 LRMP  |              | roost      |                   |
| BO); Note: As a    |              | trees      |                   |
| result of new      |              |            |                   |
| information, this  |              |            |                   |
| Forest is now      |              |            |                   |
| operating under a  |              |            |                   |
| "not likely to     |              |            |                   |
| adversely affect"  |              |            |                   |
| determination, and |              |            |                   |
| this BO is no      |              |            |                   |
| longer in effect.  |              |            |                   |
+--------------------+--------------+------------+-------------------+
| 1986 (as amended)  | West         | IT by      | A maximum of      |
| Monongahela        | Virginia FO  | killing,   | 6,125 acres       |
| National Forest    |              | harming,   | annually and      |
| Land and Resource  | March 2002   | or         | prescribed        |
| Management Plan    |              | harassing  | burning on a      |
| (Forest Plan);     |              |            | maximum of 300    |
| Note -- This BO    |              |            | acres annually.   |
| has been           |              |            |                   |
| superceded by a    |              |            |                   |
| July 2006 BO.      |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Huron-Manistee     | Michigan FO  | IT by      | 0-65 bats; 3,150  |
| National Forest    |              | killing,   | ac (1,275 ha) of  |
| LRMP; Note: This   | June 13,     | harming,   | potential Indiana |
| Bo has been        | 2003         | or         | bat habitat may   |
| superceded by a    |              | harassing  | be harvested and  |
| March 2006 BO.     |              |            | 2,648 ac (1,071   |
|                    |              |            | ha) of habitat    |
|                    |              |            | may be burned for |
|                    |              |            | fire management   |
|                    |              |            | or wildlife       |
|                    |              |            | habitat           |
|                    |              |            | management        |
|                    |              |            | activities for    |
|                    |              |            | the duration of   |
|                    |              |            | this proposed     |
|                    |              |            | action            |
+--------------------+--------------+------------+-------------------+
| Great Smoky        | Tennessee FO | IT by loss | One maternity     |
| Mountains National |              | of         | colony            |
| Park Prescribed    | August 12,   | suitable   |                   |
| Burning            | 2003         | roosting   |                   |
|                    |              | or         |                   |
|                    |              | foraging   |                   |
|                    |              | habitat    |                   |
+--------------------+--------------+------------+-------------------+
| Construction,      | Indiana FO   | IT by      | Summer action     |
| Operation, and     |              | harming,   | area: permanent   |
| Maintenance of     | December 3,  | killing    | direct & indirect |
| Alternative 3C of  | 2003         |            | loss of up to     |
| Interstate 60 from |              |            | 1527 acres of     |
| Indianapolis to    |              |            | forested habitat  |
| Evansville         |              |            | and 40 acres of   |
|                    |              |            | non-forested      |
|                    |              |            | wetlands. Winter  |
|                    |              |            | action area:      |
|                    |              |            | permanent loss of |
|                    |              |            | up to 947 acres   |
|                    |              |            | of forest habitat |
|                    |              |            | around 10 known   |
|                    |              |            | hibernacula.      |
|                    |              |            | Death by vehicle  |
|                    |              |            | collisions: 10    |
|                    |              |            | Indiana bats per  |
|                    |              |            | year.             |
+--------------------+--------------+------------+-------------------+
| 2003 Revised       | Virginia FO  | IT by      | 16,800 acres      |
| Jefferson National |              | killing,   | total (15,000     |
| Forest Land and    | January 2004 | harming,   | fire; 1,800 other |
| Resource           |              | or         | habitat           |
| Management Plan,   |              | harassing  | manipulations)    |
| Virginia, West     |              |            |                   |
| Virginia, Kentucky |              |            |                   |
+--------------------+--------------+------------+-------------------+
| 2004 Daniel Boone  | Kentucky FO  | IT by      | Green tree        |
| National Forest    |              | killing,   | harvest -- 4000   |
| Revised LRMP       | March 20,    | harming,   | acres;            |
|                    | 2004         | or         | S                 |
| Note: BO has been  |              | harassing  | alvage/sanitation |
| superceded by a    |              |            | -- 350 acres;     |
| April 2007 BO.     |              |            | Prescribed        |
|                    |              |            | burning during    |
|                    |              |            | summer -- 50,000  |
|                    |              |            | acres             |
+--------------------+--------------+------------+-------------------+
| Upper Mississippi  | Rock Island  | IT by      | 511 acres of      |
| River -- Illinois  | (IL) FO      | injury,    | forested habitat  |
| Waterway System    |              | death,     | annually for 50   |
| Navigation         | August 2004  | harming or | years. Less than  |
| Feasibility Study  |              | harassing  | 20 bats per year. |
+--------------------+--------------+------------+-------------------+
| Department of the  | Ohio FO      | IT by      | 18 acres of high  |
| Army 88^th^        |              | harming or | quality roosting  |
| Regional Readiness | April 14,    | harassing  | and foraging      |
| Command, US Army   | 2005         |            | habitat           |
| Reserve Center     |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Construction,      | Ohio FO      | IT by      | No more than 10   |
| Operation, and     |              | harming,   | Indiana bats      |
| Maintenance of the | April 15,    | death,     |                   |
| U.S. 33            | 2005         | injury     |                   |
| Nelsonville Bypass |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Big Monon Ditch    | Indiana FO   | IT by      | Permanent loss of |
| Reconstruction     |              | harming    | 75 acres of       |
| Project            | May 24, 2005 | and        | occupied summer   |
|                    |              | harassing  | habitat           |
+--------------------+--------------+------------+-------------------+
| Mark Twain         | Missouri FO  | IT through | 10 occupied roost |
| National Forest    |              | removal of | trees over 10     |
| 2005 Forest Plan,  | September    | roost      | years; 19,400     |
| Missouri; Note:    | 2005         | trees      | acres and 240     |
| Replaces June 1999 |              |            | miles of fireline |
| BO.                |              |            |                   |
+--------------------+--------------+------------+-------------------+
| BO on the          | Kentucky FO  | IT through | The level of take |
| Interstate 69      |              | harm,      | authorized is for |
| (I-69) preferred   | October 2005 | h          | those wooded      |
| alternative #2     |              | arassment, | areas of occupied |
| from Henderson,    |              | and/or     | and/or            |
| Kentucky to        |              | mortality  | potentially       |
| Evansville,        |              |            | occupied Indiana  |
| Indiana, and its   |              |            | bat habitat       |
| effects on the     |              |            | within the        |
| Indiana bat;       |              |            | construction      |
| Henderson County,  |              |            | limits of the     |
| Kentucky and       |              |            | proposed project  |
| Vanderburgh        |              |            | that lie within   |
| County, Indiana    |              |            | the Indiana bat   |
|                    |              |            | focus area        |
|                    |              |            | identified in the |
|                    |              |            | BA, which was     |
|                    |              |            | determined to be  |
|                    |              |            | about 28 acres of |
|                    |              |            | wooded habitat    |
|                    |              |            | and all of the    |
|                    |              |            | potential Indiana |
|                    |              |            | bat roost trees   |
|                    |              |            | contained within  |
|                    |              |            | those 28 acres.   |
+--------------------+--------------+------------+-------------------+
| Wayne National     | Ohio FO      | IT through | No more than 4    |
| Forest Land and    |              | removal of | occupied roost    |
| Resource           | November     | roost      | trees will be     |
| Management Plan;   | 2005         | trees      | incidentally      |
| Note: Replaced     |              |            | taken over the    |
| September 20, 2001 |              |            | next ten years;   |
| BO.                |              |            | Permanent Road    |
|                    |              |            | Construction &    |
|                    |              |            | Reconstruction    |
|                    |              |            | -392 acres;       |
|                    |              |            | Temporary Road    |
|                    |              |            | Construction -146 |
|                    |              |            | acres; Skid       |
|                    |              |            | Trails and Log    |
|                    |              |            | Landings - 740    |
|                    |              |            | acres; Utility    |
|                    |              |            | Development - 50  |
|                    |              |            | acres; Fire       |
|                    |              |            | Lines - 74 miles  |
+--------------------+--------------+------------+-------------------+
| Shawnee National   | Illinois FO  | IT through | First 10 Years of |
| Forest LRMP        |              | harming,   | plan: \-- 11,565  |
|                    | December 3,  | harassing, | acres of timber   |
|                    | 2005         | and        | harvest/mgt. and  |
|                    |              | killing    | minerals mgt. \-- |
|                    |              |            | 5,630 acres of    |
|                    |              |            | timber stand      |
|                    |              |            | improvement and   |
|                    |              |            | wetlands mgt.     |
|                    |              |            | Second 10 Years   |
|                    |              |            | of plan: \--      |
|                    |              |            | 21,255 acres of   |
|                    |              |            | timber            |
|                    |              |            | harvest/mgt. and  |
|                    |              |            | minerals mgt. \-- |
|                    |              |            | 13,289 acres of   |
|                    |              |            | timber stand      |
|                    |              |            | improvement and   |
|                    |              |            | wetlands mgt.     |
|                    |              |            | Mortality of up   |
|                    |              |            | to 2 individuals  |
|                    |              |            | during research   |
|                    |              |            | and monitoring.   |
+--------------------+--------------+------------+-------------------+
| North East         | West         | IT by      | 124 acres timber  |
| Research Station   | Virginia FO  | potential  | harvest and 466   |
| -- Fernow          |              | harm or    | acres of          |
| Experimental       | December     | mortality  | prescribed burns  |
| Forest -- Five     | 2005         | of         | (previous 210     |
| year plan; Note:   |              | roosting   | acres timber      |
| Replaced November  |              | bats       | harvest and 154   |
| 2000 5-year BO.    |              |            | acres prescribed  |
|                    |              |            | burn)             |
+--------------------+--------------+------------+-------------------+
| Final Biological   | Kentucky FO  | IT through | The level of      |
| Opinion on         |              | harm,      | incidental take   |
| implementation of  | December     | h          | authorized is     |
| the 2003 Ice Storm | 2006         | arassment, | 4,704 acres of    |
| Recovery Project   |              | and/or     | commercial        |
| and it effects on  |              | mortality  | removal of        |
| the Indiana bat,   |              |            | damaged trees and |
| Morehead Ranger    |              |            | restoration and   |
| District, Daniel   |              |            | creation of bat   |
| Boone National     |              |            | habitat when      |
| Forest, Rowan      |              |            | accomplished      |
| County, Kentucky   |              |            | during the summer |
|                    |              |            | roosting period   |
|                    |              |            | of the Indiana    |
|                    |              |            | bat (April 1 to   |
|                    |              |            | September 15).    |
+--------------------+--------------+------------+-------------------+
| Hoosier National   | Indiana FO   | IT by      | No more than four |
| Forest LRMP; Note: |              | injury or  | (4) occupied      |
| This BO replaced   | January 2006 | death or   | roost trees/year  |
| the June 2001 BO.  |              | harassing  | and between four  |
|                    |              |            | (4) and twelve    |
|                    |              |            | (12) individuals  |
|                    |              |            | injured or killed |
|                    |              |            | each year.        |
|                    |              |            | 2956-acres; 60    |
|                    |              |            | hazard trees; 100 |
|                    |              |            | "accident" trees  |
|                    |              |            | per year          |
+--------------------+--------------+------------+-------------------+
| Huron-Manistee     | Michigan FO  | IT through | For first 10      |
| National Forest    |              | harming,   | years of revised  |
| LRMP               | March 2006   | harassing, | Forest Plan:      |
|                    |              | and        | Thinning = 59,497 |
|                    |              | killing    | Clearcut = 45,144 |
|                    |              |            | Shelterwood =     |
|                    |              |            | 8,261 Selection = |
|                    |              |            | 0                 |
+--------------------+--------------+------------+-------------------+
| Biological Opinion | West         | IT in the  | No more than 17   |
| -- Impacts of the  | Virginia FO  | form of    | adult females and |
| Laxare East and    |              | harm due   | their pups; 912   |
| Black Castle       | March 2006   | to habitat | acres of forested |
| Contour Coal       |              | loss,      | habitat and 5.0   |
| Mining Projects on |              | d          | miles of stream   |
| the Indiana bat;   |              | egradation |                   |
| Note: Reinitiation |              | and        |                   |
| of February 2005   |              | frag       |                   |
| BO.                |              | mentation, |                   |
|                    |              | Harassment |                   |
|                    |              | during     |                   |
|                    |              | active     |                   |
|                    |              | mining,    |                   |
|                    |              | Permanent  |                   |
|                    |              | loss of    |                   |
|                    |              | foraging   |                   |
|                    |              | loss and   |                   |
|                    |              | roosting   |                   |
|                    |              | habitat,   |                   |
|                    |              | habitat    |                   |
|                    |              | fra        |                   |
|                    |              | gmentation |                   |
|                    |              | and        |                   |
|                    |              | de         |                   |
|                    |              | gradation, |                   |
|                    |              | permanent  |                   |
|                    |              | loss of    |                   |
|                    |              | streams    |                   |
|                    |              | and their  |                   |
|                    |              | associated |                   |
|                    |              | watering   |                   |
|                    |              | and prey   |                   |
|                    |              | base for   |                   |
|                    |              | Indiana    |                   |
|                    |              | bats, long |                   |
|                    |              | term       |                   |
|                    |              | alteration |                   |
|                    |              | of streams |                   |
+--------------------+--------------+------------+-------------------+
| Hoosier National   | Indiana FO   | Death and  | Project-wide      |
| Forest's Proposed  |              | injury     | Combined Total:   |
| Tell City          | April 2006   | from       | 8,525 acres       |
| Windthrow 2004     |              | direct     |                   |
| Salvage Timber     |              | felling of |                   |
| Harvest            |              | occupied   |                   |
|                    |              | trees;     |                   |
|                    |              | Harassment |                   |
|                    |              | of         |                   |
|                    |              | roosting   |                   |
|                    |              | bats from  |                   |
|                    |              | noises/    |                   |
|                    |              | v          |                   |
|                    |              | ibrations/ |                   |
|                    |              | d          |                   |
|                    |              | isturbance |                   |
|                    |              | levels     |                   |
|                    |              | causing    |                   |
|                    |              | roost-site |                   |
|                    |              | a          |                   |
|                    |              | bandonment |                   |
|                    |              | and        |                   |
|                    |              | atypical   |                   |
|                    |              | exposure   |                   |
|                    |              | to day     |                   |
|                    |              | time       |                   |
|                    |              | predators  |                   |
|                    |              | while      |                   |
|                    |              | fleeing    |                   |
|                    |              | and        |                   |
|                    |              | seeking    |                   |
|                    |              | new        |                   |
|                    |              | shelter    |                   |
|                    |              | during the |                   |
|                    |              | day-time;  |                   |
|                    |              | and Harm   |                   |
|                    |              | through    |                   |
|                    |              | the loss   |                   |
|                    |              | of primary |                   |
|                    |              | and/or     |                   |
|                    |              | alternate  |                   |
|                    |              | roost      |                   |
|                    |              | trees      |                   |
+--------------------+--------------+------------+-------------------+
| Final Programmatic | Kentucky FO  | IT through | The level of take |
| BO on Minor road   |              | harming,   | authorized is for |
| Construction       | June 2006    | h          | those wooded      |
| Projects in        |              | arassment, | areas of Indiana  |
| Kentucky and their |              | mortality  | bat habitat       |
| effects on the     |              |            | within the        |
| Indiana bat        |              |            | construction      |
|                    |              |            | limits of a       |
|                    |              |            | proposed project  |
|                    |              |            | covered by Tier 2 |
|                    |              |            | during KYTC FY    |
|                    |              |            | 2006 through KYTC |
|                    |              |            | FY 2010, which    |
|                    |              |            | was determined to |
|                    |              |            | be 500 acres of   |
|                    |              |            | Indiana bat       |
|                    |              |            | habitat as        |
|                    |              |            | described in the  |
|                    |              |            | HAM in KYTC FY06, |
|                    |              |            | 600 acres in KYTC |
|                    |              |            | FY07, 720 acres   |
|                    |              |            | in KYTC FY08, 864 |
|                    |              |            | acres in KYTC     |
|                    |              |            | FY09, 1,037 acres |
|                    |              |            | in KYTC FY10.     |
+--------------------+--------------+------------+-------------------+
| Programmatic       | West         | IT through | 10,052 acres of   |
| Biological Opinion | Virginia FO  | harming,   | suitable Indiana  |
| for the            |              | h          | bat habitat       |
| Monongahela        | July 2006    | arassment, | annually          |
| National Forest    |              | and/or     |                   |
| 2006 Forest Plan   |              | mortality  |                   |
| Revision           |              |            |                   |
+--------------------+--------------+------------+-------------------+
| Proposed           | Indiana FO   | Death/kill | 2,148 acres of    |
| Construction,      |              | and/or     | forested habitat  |
| Operation, and     | August 2006  | in         | and 20 acres of   |
| Maintenance of     |              | jury/wound | non-forested      |
| Alt. 3C of         |              | from       | wetlands within   |
| Interstate 69 from |              | direct     | summer action     |
| Evansville to      |              | felling of | area; 1,097 acres |
| Indianapolis       |              | occupied   | of forested       |
|                    |              | trees,     | habitat within    |
|                    |              | direct     | winter action     |
|                    |              | collision  | area; 11          |
|                    |              | with       | individuals per   |
|                    |              | vehicles,  | year from         |
|                    |              | and other  | collision with    |
|                    |              | sources.   | vehicles          |
+--------------------+--------------+------------+-------------------+
| Review of Ongoing  | Tennessee FO | No take    | No take provided  |
| Operations and     |              | provided   |                   |
| Maintenance        | October 2006 |            |                   |
| Activities at      |              |            |                   |
| Tennessee Valley   |              |            |                   |
| Authority Dams in  |              |            |                   |
| the Tennessee      |              |            |                   |
| River Basin        |              |            |                   |
| located in         |              |            |                   |
| Alabama, Georgia,  |              |            |                   |
| Kentucky,          |              |            |                   |
| Mississippi, North |              |            |                   |
| Carolina,          |              |            |                   |
| Tennessee, and     |              |            |                   |
| Virginia and Their |              |            |                   |
| Effects on         |              |            |                   |
| Federally Listed   |              |            |                   |
| Endangered and     |              |            |                   |
| Threatened Species |              |            |                   |
| per Section 7 of   |              |            |                   |
| the ESA            |              |            |                   |
+--------------------+--------------+------------+-------------------+
| BO on the Ohio     | Ohio FO      | IT through | 22,118 acres of   |
| DOT's Statewide    |              | harm,      | suitable Indiana  |
| Transportation     | January 2007 | h          | bat habitat       |
| Program for the    |              | arassment, |                   |
| Indiana bat        |              | and/or     |                   |
|                    |              | death      |                   |
+--------------------+--------------+------------+-------------------+
| 2007 Daniel Boone  | Kentucky FO  | IT by      | Green tree        |
| National Forest    |              | killing,   | harvest -- 4000   |
| Revised BO on      | April 2007   | harming,   | acres;            |
| implementation of  |              | or         | S                 |
| the revised LRMP   |              | harassing  | alvage/sanitation |
| and its effects on |              |            | -- 350 acres;     |
| the Indiana bat    |              |            | Prescribed        |
|                    |              |            | burning during    |
| Note: Replaced     |              |            | summer -- 50,000  |
| March 20, 2004 BO. |              |            | acres             |
+--------------------+--------------+------------+-------------------+
| The Effects of the | Pennsylvania | IT through | All Indiana bats  |
| U.S. 6219, Section | FO           | harm,      | dependent on 375  |
| 019,               |              | and/or     | acres of          |
| Transportation     | October 2007 | harassment | potential         |
| Improvement        |              |            | foraging and      |
| Project            |              |            | roosting habitat  |
| (Meyersdale,       |              |            | and near          |
| Somerset County,   |              |            | blas              |
| Pennsylvania to    |              |            | ting/construction |
| I-68 in Garrett    |              |            |                   |
| County, Maryland)  |              |            |                   |
| on the Indiana bat |              |            |                   |
+--------------------+--------------+------------+-------------------+

[^1]: Hibernacula priorities are primarily assigned based on winter
    population sizes.