[Federal Register Volume 78, Number 191 (Wednesday, October 2, 2013)]
[Rules and Regulations]
[Pages 61004-61043]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-23401]
[[Page 61003]]
Vol. 78
Wednesday,
No. 191
October 2, 2013
Part II
Department of the Interior
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Fish and Wildlife Service
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50 CFR Part 17
Endangered and Threatened Wildlife and Plants; Endangered Species
Status for the Florida Bonneted Bat; Final Rule
Federal Register / Vol. 78 , No. 191 / Wednesday, October 2, 2013 /
Rules and Regulations
[[Page 61004]]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R4-ES-2012-0078; 4500030113]
RIN 1018-AY15
Endangered and Threatened Wildlife and Plants; Endangered Species
Status for the Florida Bonneted Bat
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service, determine endangered
species status under the Endangered Species Act of 1973, as amended,
for the Florida bonneted bat (Eumops floridanus), a bat species from
south Florida. This final rule adds this species to the List of
Endangered and Threatened Wildlife and implements the Federal
protections provided by the Act for this species.
DATES: This rule is effective November 1, 2013.
ADDRESSES: This final rule is available on the internet at http://www.regulations.gov and at the South Florida Ecological Services Field
Office. Comments and materials we received, as well as supporting
documentation we used in preparing this rule, are available for public
inspection at http://www.regulations.gov and by appointment, during
normal business hours at: U.S. Fish and Wildlife Service, South Florida
Ecological Services Field Office, 1339 20th Street, Vero Beach, FL
32960-3559; telephone 772-562-3909; facsimile 772-562-4288.
FOR FURTHER INFORMATION CONTACT: Larry Williams, Field Supervisor, U.S.
Fish and Wildlife Service, South Florida Ecological Services Field
Office (see ADDRESSES section). If you use a telecommunications device
for the deaf (TDD), call the Federal Information Relay Service (FIRS)
at 800-877-8339.
SUPPLEMENTARY INFORMATION:
Executive Summary
This rule lists the Florida bonneted bat as an endangered species
under the Endangered Species Act of 1973 (Act), as amended. We intend
to publish a separate rule proposing designation of critical habitat
for the Florida bonneted bat in the near future.
Why we need to publish a rule. Under the Act, a species or
subspecies may warrant protection through listing if it is endangered
or threatened throughout all or a significant portion of its range.
Listing a species as endangered or threatened can only be completed by
issuing a rule. On October 4, 2012, we published a proposed rule to
list the Florida bonneted bat as an endangered species (77 FR 60750).
After careful consideration of all public and peer reviewer comments we
received, we are publishing this final rule to list the Florida
bonneted bat as an endangered species.
The basis for our action. Under the Act, a species may be
determined to be an endangered or threatened species based on any of
five factors: (A) The present or threatened destruction, modification,
or curtailment of its habitat or range; (B) overutilization for
commercial, recreational, scientific, or educational purposes; (C)
disease or predation; (D) the inadequacy of existing regulatory
mechanisms; or (E) other natural or manmade factors affecting its
continued existence. We have determined that the Florida bonneted bat
is an endangered species based on three of these five factors (Factors
A, D, and E). Specifically, habitat loss, degradation, and modification
from human population growth and associated development and agriculture
have impacted the Florida bonneted bat and are expected to further
curtail its limited range (Factor A). The effects resulting from
climate change, including sea-level rise and coastal squeeze, are
expected to become severe in the future and result in additional
habitat losses, including the loss of roost sites and foraging habitat
(Factor A). The Florida bonneted bat is also facing threats from a wide
array of natural and manmade factors (Factor E), including small
population size, restricted range, few colonies, slow reproduction, low
fecundity, and relative isolation. Existing regulatory mechanisms
(Factor D) are inadequate to reduce these threats. Overall, impacts
from increasing threats, operating singly or in combination, place the
species at risk of extinction.
Peer review and public comment. We sought comments from independent
specialists to ensure that our designation is based on scientifically
sound data, assumptions, and analyses. We received responses from six
peer reviewers. Peer reviewers generally concurred with the basis for
listing the Florida bonneted bat and provided additional information,
clarifications, and suggestions to improve this final listing
determination. We considered all comments and information we received
during the public comment period.
Previous Federal Actions
The Florida bonneted bat (Eumops floridanus) was previously known
as the Florida mastiff bat (Eumops glaucinus floridanus).
Federal actions for the Florida bonneted bat prior to October 4,
2012, are outlined in our proposed rule (77 FR 60750), which was
published on that date. Publication of the proposed rule (77 FR 60750)
opened a 60-day comment period, which closed on December 3, 2012.
Our proposed rule also included a finding that designation of
critical habitat was prudent, but that critical habitat was not
determinable. Under the Act, the Service has 2 years from the date of
the proposed listing to designate critical habitat. Accordingly, we
intend to publish a separate rule proposing designation of critical
habitat for the Florida bonneted bat in the near future.
Background
The Florida bonneted bat is a member of the Molossidae (free-tailed
bats) family within the order Chiroptera. The species is the largest
bat in Florida (Owre 1978, p. 43; Belwood 1992, p. 216; Florida Bat
Conservancy [FBC] 2005, p. 1). Males and females are not significantly
different in size, and there is no pattern of size-related geographic
variation in this species (Timm and Genoways 2004, p. 857).
Members of the genus Eumops have large, rounded pinnae (ears),
arising from a single point or joined medially on the forehead (Best et
al. 1997, p. 1). The common name of ``bonneted bat'' originates from
characteristic large broad ears, which project forward over the eyes
(FBC 2005, p. 1). Ears are joined at the midline of the head. This
feature, along with its large size, distinguishes the Florida bonneted
bat from the smaller Brazilian (=Mexican) free-tailed bat (Tadarida
brasiliensis).
Wings of the members of the genus Eumops are among the narrowest of
all molossids (Freeman 1981, as cited in Best et al. 1997, p. 3) and
are well-adapted for rapid, prolonged flight (Vaughan 1959 as cited in
Best et al. 1997, p. 3). This wing structure is conducive to high-speed
flight in open areas (Findley et al. 1972 as cited in Best et al. 1997,
p. 3).
The Florida bonneted bat's fur is short and glossy, with hairs
sharply bicolored with a white base (Belwood 1992, p. 216; Timm and
Genoways 2004, p. 857). Like other molossids, color is highly variable,
varying from black to brown to brownish-gray or cinnamon brown with
ventral pelage (fur) paler than dorsal (Owre 1978, p. 43; Belwood 1992,
p. 216; Timm and Genoways 2004, p. 857).
[[Page 61005]]
Additional details about the Florida bonneted bat can be found in
the proposed listing rule (77 FR 60750).
Taxonomy
The Florida bonneted bat (Eumops floridanus) was previously known
as Florida mastiff bat, Wagner's mastiff bat, and mastiff bat (E.
glaucinus floridanus) (Owre 1978, p. 43; Belwood 1992, p. 216; Best et
al. 1997, p. 1). While earlier literature found the Florida bonneted
bat distinct at the subspecies level, the most current scientific
information confirms that E. floridanus is a full species, and this
taxonomic change has been accepted by the scientific community (Timm
and Genoways 2004, pp. 852, 856, 861; McDonough et al. 2008, pp. 1306-
1315; R. Timm, pers. comm. 2008, 2009; in litt. 2012; Baker et al.
2009, pp. 9-10). The International Union for Conservation of Nature and
Natural Resources (Timm and Arroyo-Cabrales 2008, p. 1) and the Florida
Natural Areas Inventory (FNAI) (FNAI 2013, p. 25) use the name E.
floridanus. The Florida Fish and Wildlife Conservation Commission (FWC)
(FWC 2011a, pp. 1-11; 2013, pp. 1-43) also recognizes the species as E.
floridanus, but their current endangered and threatened list uses both
names, Florida bonneted (mastiff) bat, Eumops (=glaucinus) floridanus
(see also Factor D below).
Additional details about the Florida bonneted bat's taxonomy are
provided in the proposed listing rule (77 FR 60750).
Life History
Relatively little is known about the Florida bonneted bat's life
history. Lifespan is not known. Based upon the work of Wilkinson and
South (2002, pp. 124-131), Gore et al. (2010, p. 1) inferred a lifespan
of 10 to 20 years for the Florida bonneted bat, with an average
generation time of 5 to 10 years.
The Florida bonneted bat has a fairly extensive breeding season
during summer months (Timm and Genoways 2004, p. 859). The maternity
season for most bat species in Florida occurs from mid-April through
mid-August (Marks and Marks 2008a, p. 8). During the early portion of
this period, females give birth and leave young in the roost while they
make multiple foraging excursions to support lactation (Marks and Marks
2008a, pp. 8-9). During the latter portion of the season, young and
females forage together until the young become sufficiently skilled to
forage and survive on their own (Marks and Marks 2008a, p. 9). The
Florida bonneted bat is a subtropical species, and pregnant females
have been found in June through September (FBC 2005, p. 1; Marks and
Marks 2008a, p. 9). Examination of limited data suggests that this
species may be polyestrous (having more than one period of estrous in a
year), with a second birthing season possibly in January and February
(Timm and Genoways 2004, p. 859; FBC 2005, p. 1).
Information on reproduction and demography is sparse. The Florida
bonneted bat has low fecundity; litter size is one (FBC 2005, p. 1;
Timm and Arroyo-Cabrales 2008, p. 1). The colony studied by Belwood
(1981, p. 412) consisted of eight adults and included five post-
lactating females, one pregnant female with a single fetus, and one
male with enlarged testicles; the other female escaped before
examination. The pregnant female captured was the first record of a
gestating Florida bonneted bat in September (Belwood 1981, p. 412).
However, Belwood (1981, p. 412) noted that this finding is consistent
with the reproductive chronology of bonneted bats in Cuba, which are
polyestrous. Robson et al. (1989, p. 81) found an injured pregnant
female in Coral Gables in late August 1988, which aborted its fetus in
early September 1988. A landowner with an active colony in North Fort
Myers reported that she has seen young bats appear in spring and
summer, generally with only one or two births within the colony per
year (S. Trokey, pers. comm. 2006a). However, four young were noted in
2004 (S. Trokey, pers. comm. 2006a). The capture of a juvenile male in
a mist net at Picayune Strand State Forest (PSSF) on December 17, 2009,
suggested that there was breeding in the area (Smith 2010, p. 1-2).
Based upon limited information, the species roosts singly or in
colonies consisting of a male and several females (Belwood 1992, p.
221). G.T. Hubbell believed that individuals in Miami roosted singly
(Belwood 1992, p. 221). However, Belwood (1981, p. 412) suggested that
a colony, consisting of seven females and one male using a longleaf
pine cavity as a roost site in Punta Gorda, was a harem group, based on
its sex ratio. Belwood (1981, p. 412; 1992, p. 221) suggested that this
behavior has been recorded in a few bat species and such social
groupings may be facilitated by roosting in tree cavities, which can be
defended from other males (Morrison 1979, pp. 11-15).
Information on roosting habits from artificial structures is also
limited. The Florida bonneted bat colony using bat houses on private
property in Lee County consisted of 8 to 25 individuals, including one
albino (S. Trokey, pers. comm. 2006a, 2006b, 2008a, 2008b, 2012a,
2013). After prolonged cold temperatures killed and displaced several
bats in early 2010, a total of 10 individuals remained by April 2010,
with seven occupying one house and three occupying another (S. Trokey,
pers. comm. 2010a, 2010b, 2010c). As of March 2013, there are 20 bats
using two houses at this location (S. Trokey, pers. comm. 2013). Sex
ratio is not known. Some movement between the houses has been observed;
the albino individual has been observed to be in one house one day and
the other house the next (S. Trokey, pers. comm. 2006a).
At the Fred C. Babcock/Cecil M. Webb Wildlife Management Area
(Babcock-Webb WMA), 39 to 43 individuals have been found to use 3 to 5
separate roosts (all bat houses) during periodic simultaneous counts
conducted on 4 occasions over the past year (FWC, in litt. 2012; Marks
and Marks 2012, pp. 8, 12, A61; J. Myers, pers. comm. 2012a, 2012b,
2013). Simultaneous counts taken at emergence on April 2, 2013, at 4
roosts sites, documented 39 individuals with the number at each roost
as follows: 37, 1, 1, and 0 (J. Myers, pers. comm. 2013). Periodic
simultaneous counts taken at roosts over the course of a year suggest
that use fluctuates among five roost sites (FWC, in litt. 2012; J.
Myers, pers. comm. 2013). Apparent `non-use' of a previous roost during
monitoring may not be indicative of permanent abandonment (J. Myers,
pers. comm. 2013). It is not known if there is movement between houses
or among roost locations or between artificial and unknown natural
roosts within Babcock-Webb WMA.
Understanding of roosting behavior and site selection is limited.
However, there is a high probability that individuals tend towards high
roost site fidelity (H. Ober, in litt. 2012). Lewis (1995, pp. 481-496)
found that bats that roost in buildings tend to be more site-faithful
than those that roost in trees. Among bats that roost in trees, those
that use cavities in large trees tend to be more site-faithful than
those that use smaller trees (Brigham 1991; Fenton and Rautenbach 1986;
Fenton et al. 1993 as cited in Lewis 1995, p. 487; H. Ober, in litt.
2012). Given its size, the Florida bonneted bat is likely to select
large trees (H. Ober, in litt. 2012). The large accumulation of guano
(excrement) 1 meter (m) (3.3 feet (ft)) deep in one known natural roost
felled in 1979 (see Belwood 1981, p. 412) suggests high roost fidelity,
especially considering the small number of individuals per colony (H.
Ober, in litt. 2012).
The Florida bonneted bat is active year-round and does not have
periods of hibernation or torpor. The species is not
[[Page 61006]]
migratory, but there might be seasonal shifts in roosting sites (Timm
and Genoways 2004, p. 860). Belwood (1992, pp. 216-217) reported that,
prior to 1967, G.T. Hubbell routinely obtained several individuals per
year collected during the winter from people's houses.
Precise foraging and roosting habits and long-term requirements are
unknown (Belwood 1992, p. 219). Active year-round, the species is
likely dependent upon a constant and sufficient food supply, consisting
of insects, to maintain its generally high metabolism. The available
information indicates Florida bonneted bats feed on flying insects of
the following orders: Coleoptera (beetles), Diptera (flies), Hemiptera
(true bugs), and Lepidoptera (moths) (Belwood 1981, p. 412; Belwood
1992, p. 220; FBC 2005, p. 1; Marks 2013, pp. 1-2). An analysis of bat
guano (droppings) from the colony using the pine flatwoods in Punta
Gorda indicated that the sample (by volume) contained coleopterans (55
percent), dipterans (15 percent), and hemipterans (10 percent) (Belwood
1981, p. 412; Belwood 1992, p. 220). More recent analyses of bat guano
collected from occupied bat houses at Babcock-Webb WMA indicated that
the samples contained high percentages of Lepidoptera and Coleoptera
(Marks 2013, pp. 1-2). In one analysis of 50 fecal pellets (from
approximately 35 individuals taken April 2013), samples (by volume)
contained about 49 percent Lepidoptera, 35 percent Coleoptera, and 17
percent unknown (Marks 2013, p. 1). Analyses of samples taken in May
2011 (n=6) and June 2011 (n=6) at the same location also indicated that
high percentages of Lepidoperta (74 percent, 49 percent) and Coleoptera
(26 percent, 35 percent) were consumed (Marks 2013, pp. 1-2). Florida
bonneted bats were found to feed on large insects at this location;
however, specific prey could not be determined because the bats
apparently culled parts of the insects such as heads, legs, antennae,
elytra, and wings (Marks 2013, pp. 1-2).
Researchers are planning to conduct analyses of guano to determine
dietary preferences and seasonal changes (Ridgley 2012, pp. 1-4; C.
Marks, FBC, pers. comm. 2012a; S. Snow, Everglades National Park (ENP),
pers. comm. 2012a; Marks 2013, p. 2). This species may prey upon larger
insects, which may be less abundant than smaller prey items (S. Snow,
pers. comm. 2012a). Since the species can take flight from the ground
like other Eumops species, the Florida bonneted bat may also prey upon
ground insect species (Ridgley 2012, pp. 1-2). Based upon recent
analyses, Marks (2013, p. 2) recommended that natural habitats
conducive to insect diversity be protected and that any pesticides be
used with caution.
Molossids, in general, seem adapted to fast flight in open areas
(Vaughan 1966, p. 249). Various morphological characteristics (e.g.,
narrow wings, high wing-aspect ratios (ratio of wing length to its
breadth)) make Eumops species well-adapted for efficient, rapid, and
prolonged flight in open areas (Findley et al. 1972, pp. 429-444;
Freeman 1981, pp. 96-97; Norberg and Rayner 1987, pp. 399-400; Vaughan
1959 as cited in Best et al. 1997, p. 3). Barbour and Davis (1969, p.
234) noted that the species flies faster than smaller bats, but cannot
maneuver as well in small spaces. Belwood (1992, p. 221) stated that
Eumops glaucinus is ``capable of long, straight, and sustained
flight,'' which should allow individuals to travel large distances.
Norberg and Rayner (1987, p. 399) attributed long distance flights of
Brazilian free-tailed bats to their high wing-aspect ratios, with that
species capable of traveling 65 kilometers (km) (40 miles (mi)) from
its roosting site to its foraging areas (Barbour and Davis 1969, p.
203). In one study that used radiotelemetry tracking in Arizona,
Tibbitts et al. (2002, p. 11) found Underwood's mastiff bat (Eumops
underwoodi) ranged up to 24 km (15 mi) or more during foraging bouts
from its roost site. Tracked individuals (n=3) were found to commonly
cover large areas in a single evening (Tibbitts et al. 2002, pp. 1-12).
The largest single-night home range was 284.6 km\2\ (109.9 mi\2\), and
all three bats commonly ranged over 100 km\2\ (38.6 mi\2\) on a typical
night (Tibbitts et al. 2002, p. 12). Most bats on most nights traveled
20-30 km (12.4-18.6 mi) and often more in the range of 50-100 km (31.1-
62.1 mi) as a minimum estimate (Tibbitts et al. 2002, p. 12).
Foraging and dispersal distances and home range sizes for the
Florida bonneted bat are not known and have not been studied in detail
(K. Gillies, in litt. 2012; G. Marks, pers. comm. 2012; H. Ober, in
litt. 2012). Like other molossids, the species' morphological
characteristics make it capable of dispersing large distances and
generally adapted for low cost, swift, long distance travel from roost
site to foraging areas (Norberg and Rayner 1987, pp. 399-400; K.
Gillies, in litt. 2012; H. Ober, in litt. 2012). Given this, it seems
likely that foraging areas may be located fairly long distances from
roost sites (H. Ober, in litt. 2012). However, despite its
capabilities, the species likely does not travel farther than necessary
to acquire food needed for survival (G. Marks, pers. comm. 2012a).
Bonneted bats are ``fast hawking'' bats that rely on speed and
agility to catch target insects in the absence of background clutter,
such as dense vegetation (Simmons et al. 1979, pp. 16-21; Belwood 1992,
p. 221; Best et al. 1997, p. 5). Foraging in open spaces, these bats
use echolocation to detect prey at relatively long range, roughly 3 to
5 m (10 to 16 ft) (Belwood 1992, p. 221). Based upon information from
G.T. Hubbell, Belwood (1992, p. 221) indicated that individuals leave
roosts to forage after dark, seldom occur below 10 m (33 ft) in the
air, and produce loud, audible calls when flying; calls are easily
recognized by some humans (Belwood 1992, p. 221; Best et al. 1997, p.
5; Marks and Marks 2008a, p. 5). On the evening of April 19, 2012,
Florida bonneted bats using bat houses at Babcock-Webb WMA emerged to
forage at dusk; emergence began roughly 26 minutes after sunset and
continued for approximately 20 minutes (P. Halupa, pers. obs. 2012; J.
Myers, pers. comm. 2012c).
Habitat
Relatively little is known of the ecology of the Florida bonneted
bat, and long-term habitat requirements are poorly understood (Robson
1989, p. 2; Robson et al. 1989, p. 81; Belwood 1992, p. 219; Timm and
Genoways 2004, p. 859). Habitat for the Florida bonneted bat mainly
consists of foraging areas and roosting sites, including artificial
structures. At present, no active, natural roost sites are known, and
only limited information on historical sites is available.
Recent information on habitat has been obtained largely through
acoustical surveys, designed to detect and record bat echolocation
calls (Marks and Marks 2008a, p. 5). Acoustical methods have generally
been selected over mist netting as the primary survey methodology
because this species flies and primarily forages at heights of 9 m (30
ft) or more (Marks and Marks 2008a, p. 3). The Florida bonneted bat has
a unique and easily identifiable call. While most North American bats
vocalize echolocation calls in the ultrasonic range that are inaudible
to humans, the Florida bonneted bat echolocates at the higher end of
the audible range, which can be heard by some humans as high-pitched
calls (Marks and Marks 2008a, p. 5). Most surveys conducted using
acoustical equipment can detect echolocation calls within a range of 30
m (100 ft); call sequences are analyzed using software that compares
calls to a library of
[[Page 61007]]
signature calls (Marks and Marks 2008a, p. 5). Florida bonneted bat
calls are relatively easy to identify because calls are issued at
frequencies well below that of other Florida bat species (Marks and
Marks 2008a, p. 5). However, most surveys conducted for the species to
date have been somewhat limited in scope, with various methods used.
Since bat activity can vary greatly at a single location both within
and between nights (Hayes 1997, pp. 514-524; 2000, pp. 225-236), a lack
of calls during a short listening period may not be indicative of lack
of use within an area (H. Ober, in litt. 2012).
In general, open, fresh water and wetlands provide prime foraging
areas for bats (Marks and Marks 2008c, p. 4). Bats will forage over
ponds, streams, and wetlands and will drink when flying over open water
(Marks and Marks 2008c, p. 4). During dry seasons, bats become more
dependent on remaining ponds, streams, and wetland areas for foraging
purposes (Marks and Marks 2008c, p. 4). The presence of roosting
habitat is critical for day roosts, protection from predators, and the
rearing of young (Marks and Marks 2008c, p. 4). For most bats, the
availability of suitable roosts is an important, limiting factor
(Humphrey 1975, pp. 341-343). Bats in south Florida roost primarily in
trees and manmade structures (Marks and Marks 2008a, p. 8). Protective
tree cover around bat roosts may be important for predator avoidance
and allowing earlier emergence from the roost, thereby allowing bats to
take advantage of the peak in insect activity at dusk and extend
foraging time (Duverge et al. 2000, p. 39).
Available information on roosting sites for the Florida bonneted
bat is extremely limited. Roosting and foraging areas appear varied,
with the species occurring in forested, suburban, and urban areas (Timm
and Arroyo-Cabrales 2008, p. 1). Data from acoustical surveys and other
methods suggest that the species uses a wide variety of habitats (R.
Arwood, Inside-Out Photography, Inc., pers. comm. 2008a, 2008b, 2012a,
2013a-d; Marks and Marks 2008a, pp. 13-14; 2008b, pp. 2-5; 2008c, pp.
1-28; 2012, pp. 1-22; Smith 2010, pp. 1-4; S. Snow, pers. comm. 2011a,
2011b, 2012b-h; in litt. 2012; M. Owen, pers. comm. 2012a, 2012b; R.
Rau, pers. comm. 2012; Maehr 2013, pp. 1-13; S. Maehr, pers. comm.
2013a, 2013b; K. Relish, pers. comm. 2013; F. Ridgley, pers. comm.
2013a-c; B. Scofield, pers. comm. 2013a-f; K. Smith, pers. comm. 2013).
Attempts to locate natural roost sites (e.g., large cavity trees)
in February 2013 using scent-detection dogs were inconclusive. No
active natural roosts for Florida bonneted bats have been identified or
confirmed to date. At this time, all known active roost sites are
artificial structures (i.e., bat houses) (see Use of Artificial
Structures (Bat Houses) below).
Use of Forests and Other Natural Areas
Bonneted bats are closely associated with forested areas because of
their tree-roosting habits (Robson 1989, p. 2; Belwood 1992, p. 220;
Eger 1999, p. 132), but specific information is limited. Belwood (1981,
p. 412) found a small colony of Florida bonneted bats (seven females
and one male, all adults) roosting in a longleaf pine (Pinus palustris)
in a pine flatwoods community near Punta Gorda in 1979. The bats were
roosting in a cavity 4.6 m (15.1 ft) high, which had been excavated by
a red-cockaded woodpecker (Picoides borealis) and later enlarged by a
pileated woodpecker (Dryocopus pileatus) (Belwood 1981, p. 412).
Belwood (1981, p. 412) suggested that the bats were permanent residents
of the tree due to the considerable accumulation of guano,
approximately 1 m (3.3 ft) in depth. Eger (1999, p. 132) noted that in
forested areas, old, mature trees are essential roosting sites for this
species. The species also uses foliage of palm trees. Based upon
information from G.T. Hubbell, specimens have been found in shafts of
royal palms (Roystonea regia) (Belwood 1992, p. 219).
Similar roosting habitats have been reported for E. g. glaucinus in
Cuba. Nine of 19 known E. g. glaucinus roost sites were located in tree
cavities, including woodpecker holes and cavities in royal palms,
``degame'' trees (Callycophyllum candidissimum), and mastic trees
(Bursera simaruba) (Silva-Taboada 1979 as cited in Robson 1989, p. 2
and Belwood 1992, p. 219). Another individual was found roosting in the
foliage of the palm Copernicia vespertilionum (Silva-Taboada 1979 as
cited in Belwood 1992, p. 219). Belwood (1992, pp. 219-220) noted that
the majority of the approximately 80 specimens of E. glaucinus from
Venezuela housed in the U.S. National Museum were collected from tree
cavities in heavily forested areas.
More recent acoustical data and other information indicate that the
Florida bonneted bat uses forests and a variety of other natural areas.
Echolocation calls have been recorded in a wide array of habitat types:
Pine flatwoods, pine rocklands, cypress, hardwood hammocks, mangroves,
wetlands, rivers, lakes, ponds, canals, and so forth (see Table 1).
Table 1 lists locations and habitat types where Florida bonneted bats
were recorded or observed (2003 to present) (R. Arwood, pers. comm.
2008a, 2008b, 2012a, 2013a-d; Marks and Marks 2008a, pp. 13-14; 2008b,
pp. 2-5; 2008c, pp. 1-28; 2012, pp. 1-22; Smith 2010, pp. 1-4; S. Snow,
pers. comm. 2011a, 2011b, 2012b-h; in litt. 2012; M. Owen, pers. comm.
2012a, 2012b; R. Rau, pers. comm. 2012; Maehr 2013, pp. 1-13; S. Maehr,
pers. comm. 2013a, 2013b; K. Relish, pers. comm. 2013; F. Ridgley,
pers. comm. 2013a-c; B. Scofield, pers. comm. 2013a-f; K. Smith, pers.
comm. 2013). Additional details on key sites are provided below Table
1.
Table 1--Locations and Habitat Types Recorded or Observed for Florida Bonneted Bats
[2003-2013]
----------------------------------------------------------------------------------------------------------------
Site Ownership County Management Habitat type
----------------------------------------------------------------------------------------------------------------
Everglades National Park (ENP) public........... Monroe............. National Park earth midden
(coastal) (2 backcountry sites Service (NPS). hammocks,
along Wilderness Waterway mangroves.
[Darwin's Place, Watson's
Place]).
ENP (mainland) (junction of Main public........... Miami-Dade......... NPS............... pine rocklands,
Park Road and Long Pine Key). wet prairie,
tropical
hardwoods.
L-31N canal, proposed public........... Miami-Dade......... NPS and SFWMD..... canal, mixed.
transmission line corridor,
eastern boundary ENP.
Homestead, FL................... private.......... Miami-Dade......... None.............. residential,
urban.
Fairchild Tropical Botanic private.......... Miami-Dade......... FTBG.............. pine rockland,
Garden (FTBG). hardwood hammock,
water, tropical
garden,
residential.
[[Page 61008]]
Zoo Miami....................... public........... Miami-Dade......... Miami-Dade County. pine rocklands,
disturbed
nonnative areas,
developed park
lands, groves,
artificial
freshwater lakes.
Larry and Penny Thompson Park... public........... Miami-Dade......... Miami-Dade County. pine rocklands,
developed park
lands, groves,
artificial
freshwater lake.
Martinez Preserve............... public........... Miami-Dade......... Miami-Dade County. pine rocklands,
remnant
transition glade.
Coral Gables (2 sites, including private.......... Miami-Dade......... None.............. residential,
Granada Golf Course). urban.
Snapper Creek Park.............. public........... Miami-Dade......... Miami-Dade County. residential,
urban.
Everglades City................. private.......... Collier............ None.............. residential,
urban.
Naples.......................... private.......... Collier............ None.............. residential,
urban.
Florida Panther NWR (multiple public........... Collier............ U.S. Fish and pine flatwoods,
sites). Wildlife Service. wet prairie,
lakes, artificial
and ephemeral
ponds bordered by
royal palm
hammock, cypress,
pond apple, oak
hammock.
Fakahatchee Strand Preserve public........... Collier............ Florida Department lake, canal near
State Park (FSPSP) (multiple of Environmental hardwood hammock,
sites). Protection (FDEP). pine flatwoods,
strand swamp,
royal palms.
Picayune Strand State Forest public........... Collier............ FFS............... canal, wet
(PSSF) (multiple sites). prairie, pine
flatwoods,
cypress, hardwood
hammock, exotics.
Big Cypress National Preserve public........... Collier............ NPS............... pine flatwoods,
(BCNP) (multiple sites). palmetto,
cypress, mixed
and hardwood
hammocks,
mangroves, mixed
shrubs, wet
prairies, river,
lake, campground.
North Fort Myers (2 sites, private.......... Lee................ None; private residential,
including bat houses). landowner. rural, urban; bat
houses.
Babcock-Webb Wildlife Management public........... Charlotte.......... Florida Fish and pinelands (and
Area (WMA) (multiple sites). Wildlife near red-cockaded
Conservation woodpecker
Commission (FWC). clusters); bat
houses.
Babcock Ranch Preserve public, private.. Charlotte.......... Private entities, swamp.
(Telegraph Swamp). FWC, FFS, and Lee
County.
KICCO WMA....................... public........... Polk............... SWFWMD and FWC.... oxbow along
Kissimmee River.
Avon Park Air Force Range public........... Polk............... Air Force......... scrubby flatwoods,
(APAFR). next to open
water lake/pond;
wetland in scrub
habitat.
Kissimmee River Public Use Area public........... Okeecho-bee........ SWFWMD and FWC.... boat ramp along
(Platt's Bluff). Kissimmee River.
----------------------------------------------------------------------------------------------------------------
In 2006, the species was found at Babcock-Webb WMA in the general
vicinity of the colony found by Belwood (1981, p. 412); this was the
first documentation of the Florida bonneted bat at this location since
1979 (Marks and Marks 2008a, pp. 6, 11, 13). Major habitat types at
Babcock-Webb WMA include dry prairie, freshwater marsh, wet prairie,
and pine flatwoods; all calls were recorded in pinelands (Marks and
Marks 2008a, pp. A7, B38-B39; 2012, pp. 8, A61, B43). The species was
also recorded at an adjacent property, Babcock Ranch Preserve, in 2007;
calls were recorded at Telegraph Swamp, but not in the pinelands
surveyed (Marks and Marks 2008a, pp. A9, B55-B57).
The species has been found within the Fakahatchee Strand Preserve
State Park (FSPSP), using this area throughout the year (D. Giardina,
Florida Department of Environmental Protection (FDEP), pers. comm.
2006; C. Marks, pers. comm. 2006a, 2006b; M. Owen, FSPSP, pers. comm.
2012a, 2012b). In 2006, this species was found at a small lake and at a
canal adjacent to tropical hardwood hammocks (Ballard Pond and Prairie
Canal Bridge) in the FSPSP (Marks and Marks 2008a, pp. 11, A7-A9, B50-
B51). Available data and observations indicate that the species was
regularly heard at FSPSP from 2000 through 2012 at various locations,
primarily in the main strand swamp and near royal palms (M. Owen, pers.
comm. 2012a, 2012b; R. Rau, pers. comm. 2012). In November 2007, the
species was observed along U.S. 41 at Collier-Seminole State Park in
Collier County (S. Braem, FDEP, pers. comm. 2012). The FDEP also
suggests that the species may occur at Charlotte Harbor Preserve State
Park in Charlotte County and Delnor-Wiggins Pass State Park in Collier
County (P. Small, FDEP, pers. comm. 2012).
The Florida bonneted bat has been found in various habitats within
Big Cypress National Preserve (BCNP). During surveys conducted in a
variety of habitats in 2006-2007, the majority consisting of cypress
swamps and wetlands, only one Florida bonneted bat call sequence was
recorded in BCNP in 16 nights of effort (stationary and roving surveys)
(Marks and Marks 2008a, pp. 11, A12-A14). The call sequence was
recorded at Deep Lake along the western edge of BCNP and the eastern
side of the FSPSP; the lake was surrounded by cypress and hardwood
hammocks similar to the habitat around Ballard Pond in the FSPSP (see
above) (R. Arwood, pers. comm. 2008b). The species was recorded again
in February 2012 at another location (Cal Stone's camp) in an area of
pine and palmetto with cypress domes in the surrounding area (R.
Arwood, pers. comm. 2012a; Marks and Marks 2012, p. 13). Data derived
from recordings taken in 2003 and 2007 by a contractor and provided to
the Service (S. Snow, pers. comm. 2012g) and available land use covers
derived from a geographic information system also suggest that the
species uses a wide array of habitats within BCNP. Additional call data
obtained in late 2012 and early 2013 also suggest the use
[[Page 61009]]
of various habitat types, including forested areas, wetlands, and open
water in BCNP (R. Arwood, pers. comm. 2013a-d).
Recent results from a study at Florida Panther NWR conducted in
2013 also show the species' use of forested areas, open water, and
wetlands (Maehr 2013, pp. 1-13). Of the 13 locations examined, the
highest detection of Florida bonneted bat calls occurred in areas with
the largest amount of open water (Maehr 2013, p. 8). The area with the
highest detection was an open water pond, surrounded primarily by pine
flatwoods and oak hammock (S. Maehr, pers. comm. 2013a-c). That area
has been regularly burned and contains a large amount of old snags that
have been hollowed by woodpeckers (C. Maehr, pers. comm. 2013c).
As noted earlier, FWC biologists and volunteers caught a free-
flying juvenile male Florida bonneted bat in 2009, using a mist net in
the PSSF in Collier County (Smith 2010, p. 1). Habitat composition of
PSSF includes wet prairie, cypress stands, and pine flatwoods in the
lowlands and subtropical hardwood hammocks in the uplands, and the
individual was captured in the net above the Faka-Union Canal (Smith
2010, p. 1). This was particularly notable because it may have been the
first capture of a Florida bonneted bat in an area with no known roost
site (Smith 2010, p. 1). The species has been detected at nine
locations within PSSF (i.e., captured at one location, heard while mist
netting at eight other locations), and each site was located near
canals (K. Smith, pers. comm. 2013).
In 2000, the species was recorded within mangroves at Dismal Key
within the Ten Thousand Islands (Timm and Genoways 2004, p. 861; Marks
and Marks 2008a, pp. 6, A9, B53; 2012, p. 14). Subsequent surveys in
2000, 2006, and 2007 did not document any additional calls at this
location (Marks and Marks 2008a, pp. 6, 11, 14). In 2007, the species
was recorded at a backcountry campsite (Watson's Place) within ENP,
comprised of mixed hardwoods (S. Snow, pers. comm. 2012h). In 2012, the
species was found within mangroves and mixed hardwoods at another
backcountry campsite (Darwin's Place) along the Wilderness Waterway
(Ten Thousand Islands area), approximately 4.8 km (3 mi) east-southeast
of Watson's Place within ENP (Marks and Marks 2012, pp. 8, 17, A53,
B35, B38; C. Marks, pers. comm. 2012b; S. Snow, pers. comm. 2012h).
However, the species was not located in similar habitats during 18
survey nights in 2012 (Marks and Marks 2012, p. 14).
In 2011-2012, the species was recorded in various natural habitats
elsewhere in ENP and vicinity (S. Snow, pers. comm. 2011a, 2012c-f; S.
Snow, in litt. 2012; Marks and Marks 2012, pp. 8, 14). It was recorded
in wetlands, tropical hardwoods, and pinelands at the junction of the
main park road and road to Long Pine Key (S. Snow, pers. comm. 2011a,
2012f; in litt. 2012; Marks and Marks 2012, p. 8, 14, 17), and also
along the L-31N canal in a rural area, at the eastern boundary of ENP
(Marks and Marks 2012, pp. 8, 14, 17, A59; S. Snow, pers. comm. 2012c-
f; in litt. 2012). In March 2012, one suspect call sequence (presumed,
but not confirmed) was also recorded on SR 9336 in an area of rural
residential and agricultural habitat in Miami-Dade County (S. Snow,
pers. comm. 2012f). In January 2012, another suspect call was recorded
from the suburban streets of the village of Palmetto Bay in Miami-Dade
(S. Snow, pers. comm. 2012f).
In 2008, the Florida bonneted bat was recorded at two locations
along the Kissimmee River during a survey of public areas contracted by
FWC (J. Morse, pers. comm. 2008, 2010; Marks and Marks 2008b, pp. 2-5;
2008c, pp. 1-28). One location was at an oxbow along the Kissimmee
River in a pasture in KICCO WMA; the other was at Platt's Bluff boat
ramp at a public park on the Kissimmee River (Marks and Marks 2008c,
pp. 11, 17). No additional calls were detected in the Lake Kissimmee
areas or along the Kissimmee River during subsequent surveys designed
to more completely define the northern part of the Florida bonneted
bat's range in 2010-2012 (C. Marks, pers. comm. 2012c; Marks and Marks
2012, pp. 3, 5, 8, 10). However, the Florida bonneted bat was detected
elsewhere in the northern part of its range during surveys at APAFR in
2013 (B. Scofield, pers. comm. 2013a, 2013e) (see Current
Distribution). Call sequences were recorded at two locations, including
one in an area of scrubby flatwoods next to a natural open water lake/
pond and near several cavity trees and snags and another near a wetland
embedded in scrub habitat (B. Scofield, pers. comm. 2013b, 2013d,
2013e).
Use of Parks, Residential Areas, and Other Urban Areas
The Florida bonneted bat uses human structures and other nonnatural
environments. In Coral Gables (Miami area), specimens have been found
in the shafts of royal palm leaves (Belwood 1992, p. 219). Based upon
observations from G.T. Hubbell, past sightings in Miami suggest that
preferred diurnal roosts may be the shingles under Spanish tile roofs
(Belwood 1992, p. 219). The species also roosts in buildings (e.g., in
attics, rock or brick chimneys of fireplaces, and especially buildings
dating from about 1920-1930) (Timm and Arroyo-Cabrales 2008, p. 1). One
individual recently reported that a single Florida bonneted bat had
come down the chimney and into his residence in Coral Gables in the
fall about 5 years ago (D. Pearson, pers. comm. 2012). Belwood (1992,
p. 220) suggested that urban bats would appear to benefit from using
Spanish tile roofs on dwellings, since the human population in south
Florida is growing, and Spanish tile roofs are likely more common now
than in the past. However, it is important to recognize that bats using
old or abandoned and new dwellings are at significant risk; bats are
removed when structures are demolished or when they are no longer
tolerated by humans (see Summary of Factors Affecting the Species,
Factor E).
Discovery of an adult with a specimen tag indicating ``found under
rocks when bull-dozing ground'' suggests this species may also roost in
rocky crevices and outcrops on the ground (Timm and Genoways 2004, p.
860). A colony was found in a limestone outcropping on the north edge
of the University of Miami campus in Coral Gables; the limestone
contained a large number of flat, horizontal, eroded fissures in which
the bats roosted (Timm and Genoways 2004, p. 860). It is not known to
what extent such roost sites are suitable.
Recent acoustical surveys (2006, 2008, 2012) confirmed that the
species continues to use a golf course in urban Coral Gables (Marks and
Marks 2008a, pp. 6, 11, A4; 2008b, pp. 1-6; 2012, pp. 8, 14, 16, 19,
A24, B16). Despite numerous efforts, attempts to locate the roost site
have been unsuccessful.
Recordings taken continuously from a balcony from a fifth floor
condominium also detected presence in Naples (R. Arwood, pers. comm.
2008a). Recordings taken from a house and at a boat dock along the
Barron River in Everglades City also detected presence in this area (R.
Arwood, pers. comm. 2008a).
The species has been documented at Zoo Miami within an urban public
park within the Richmond Pinelands in Miami-Dade County (Marks and
Marks 2012, pp. 8, 14, 16, A26; Ridgley 2012, p. 1; F. Ridgley, pers.
comm. 2013a, 2013b). A dead specimen was found on Zoo Miami (then known
as Miami Metrozoo) grounds at the Asian Elephant barn in 2004 (Marks
and Marks 2008a, p. 6). Miami-Dade County
[[Page 61010]]
biologists observed seven bats similar in size to Florida bonneted bats
and heard chatter at the correct frequency a few years ago, but were
unable to obtain definitive recordings (S. Thompson, Miami-Dade Park
and Recreation Department, pers. comm. 2010) until a single call was
recorded by FBC outside the same enclosure in September 2011 (Marks and
Marks 2012, pp. 8, 14, 16, A26; Ridgley 2012, p. 1).
Florida bonneted bats have been recorded more recently at the Zoo
Miami, Larry and Penny Thompson Park, and the Martinez Preserve, with
peak activity in areas of artificial freshwater lakes adjacent to
intact pine rocklands (F. Ridgley, pers. comm. 2013a-c). Surrounding
habitats include pine rocklands, disturbed natural areas with invasive
plant species, freshwater lakes, developed area, open recreational
areas, and horticulturally altered landscape, with a variety of manmade
structures (J. Maguire, in litt. 2012; Ridgley 2012, p. 1; F. Ridgley,
pers. comm. 2013b). Although there are five artificial lakes on the
grounds of Zoo Miami and Larry and Penny Thompson Park, the Florida
bonneted bat appears to utilize the two that have pine rockland
adjacent to their shorelines (F. Ridgley, pers. comm. 2013b). Possible
roosting sites that exist on the properties include manmade structures,
pine snags, and limestone cavities (F. Ridgley, pers. comm. 2013b).
In 2011 and 2012, the species was recorded within tropical gardens
at Fairchild Tropical Botanic Garden (FTBG) in Miami-Dade County (S.
Snow, pers. comm. 2011b, 2012b, 2012f; Marks and Marks 2012, pp. 8, 13-
14, 17, A35, A37).
Use of Artificial Structures (Bat Houses)
The Florida bonneted bat uses non-natural environments (see Use of
Parks, Residential Areas, and other Urban Areas, above) and artificial
structures, particularly bat houses (Marks and Marks 2008a, p. 8; Morse
2008, pp. 1-14; S. Trokey, pers. comm. 2012a, 2012b). In fact, all of
the active known roosting sites for the species are bat houses (2 at a
private landowner's house; 3 to 5 separate roosts at Babcock-Webb WMA).
The species occupies bat houses on private land in North Fort
Myers, Lee County; until relatively recently, this was the only known
location of an active colony roost anywhere (S. Trokey, pers. comm.
2006a, 2008b; Marks and Marks 2008a, pp. 7, 15). The Florida bonneted
bat has used this property for over 9 years (S. Trokey, pers. comm.
2012a). The bat houses are located near a small pond, situated
approximately 5 m (17 ft) above the ground with a south-by-southwest
orientation (S. Trokey, pers. comm. 2012b). The relatively high height
of the houses may allow the large bats to fall from the roosts before
flying (S. Trokey, pers. comm. 2012b).
The species also occupies bat houses within pinelands at Babcock-
Webb WMA in Punta Gorda, Charlotte County (Marks and Marks 2012, pp. 8,
A61). In winter 2008, two colonies were found using bat houses (Morse
2008, p. 8; N. Douglass, FWC, pers. comm. 2009). In 2010, approximately
25 individuals were found at two additional bat houses, bringing the
potential total at Babcock-Webb WMA to 58 individuals, occupying four
houses (J. Birchfield, FWC, pers. comm. 2010; Marks and Marks 2012, pp.
12, A61). In 2012, 42 individuals were found to use four roost sites,
consisting of a total of seven bat houses, situated approximately 5 m
(17 ft) above the ground with north and south orientations (Marks and
Marks 2012, pp. 12, 19, A61; J. Myers, pers. comm. 2012a). In September
2012, five bats were observed using two triple-chambered houses mounted
back-to-back; this represented the fifth roost site found at Babcock-
Webb WMA (FWC, in litt. 2012). In 2013, 39 individuals were using 3
roost sites (J. Myers, pers. comm. 2013). Roosts at Babcock-Webb WMA
are mainly in hydric and mesic pine flatwoods with depression and basin
marshes and other mixed habitat in the vicinity (J. Myers, pers. comm.
2012b).
Summary
In summary, relatively little is known of the species' habitat
requirements. Based upon available data discussed above, it appears
that the species can use a wide array of habitat types (see Table 1,
above). The extremely limited available information on roosting sites
is particularly problematic, as the availability of suitable roosts is
an important limiting factor for most bat species. Existing roost sites
need to be identified so that they can be preserved and protected
(Marks and Marks 2008a, p. 15; K. Gillies, in litt. 2012). Uncertainty
regarding the location of natural and artificial roost sites may
contribute to the species' vulnerability (see Summary of Factors
Affecting the Species, Factors A and E, below). As the locations of
other potentially active roost sites are not known, inadvertent impacts
to and losses of roosts may be more likely to occur. If roost sites are
located, actions could be taken to avoid or minimize losses.
Historical Distribution
Records indicating historical range are limited. Information on the
Florida bonneted bat's historical distribution is provided in the
proposed listing rule (77 FR 60750). We did not receive any new
information during the public comment period.
Current Distribution
Endemic to Florida, the Florida bonneted bat has one of the most
restricted distributions of any species of bat in the New World
(Belwood 1992, pp. 218-219; Timm and Genoways 2004, pp. 852, 856-858,
861-862). Although numerous acoustical surveys for the Florida bonneted
bat have been conducted in the past decade by various parties, the best
scientific information indicates that the species exists only within a
very restricted range, largely confined to south and southwest Florida
(Timm and Genoways 2004, pp. 852, 856-858, 861-862; Marks and Marks
2008a, p. 15; 2012, pp. 10-11).
The majority of information relating to current distribution comes
from the following recent studies: (1) Rangewide surveys conducted in
2006-2007, funded by the Service, to determine the status of the
Florida bonneted bat following the 2004 hurricane season, and follow-up
surveys in 2008 (Marks and Marks 2008a, pp. 1-16 and appendices; 2008b,
pp. 1-6); (2) surveys conducted in 2008 along the Kissimmee River and
Lake Wales Ridge, funded by the FWC, as part of bat conservation and
land management efforts (Marks and Marks 2008c, pp. 1-28; 2008d, pp. 1-
21; Morse 2008, p. 2); (3) surveys conducted within BCNP in 2003 and
2007, funded by the NPS (S. Snow, pers. comm. 2012g), and surveys
conducted in BCNP in 2012 and 2013 through volunteer efforts (R.
Arwood, pers. comm. 2012a, 2012b, 2013a-d); (4) surveys conducted in
2011-2012 in ENP by NPS staff (S. Snow, pers. comm. 2012c-f; in litt.
2012); (5) surveys conducted in 2010-2012, funded by the Service, to
fill past gaps and better define the northern and southern extent of
the species' range (Marks and Marks 2012, pp. 1-22 and appendices); (6)
recordings taken from proposed wind energy facilities in Glades and
Palm Beach Counties (C. Coberly, Merlin Ecological, LLC., pers. comm.
2012; C. Newman, Normandeau Associates, Inc, pers. comm. 2012); and (7)
surveys conducted as part of other isolated studies. Details relating
to the bulk of these survey efforts and results were described in
detail in the proposed listing rule (77 FR 60750). Only new information
or relevant findings are provided below.
[[Page 61011]]
It is important to note that most surveys were limited in scope,
and various methods and equipment were used. In many cases, relatively
short listening intervals were employed (generally >1 hour in duration,
often multiple hours). Only a few studies sampled the same areas on
more than one occasion or for consecutive nights. More robust study
designs would account for sources of temporal, spatial, and sampling
variation and explicitly state underlying assumptions (Hayes 1997, pp.
514-524; 2000, pp. 225-236).
(1) Surveys in Big Cypress
Data from acoustical surveys conducted from December 7, 2012,
through July 11, 2013, documented presence at seven sites within BCNP
(R. Arwood, pers. comm. 2013a-d). In this effort, continuous recordings
were taken from sundown to sunrise over multiple nights at each site
survey site (R. Arwood, pers. comm. 2012b). As of July 11, 2013, a
total of 747 Florida bonneted bat calls were recorded out of 36,441
total calls over 296 nights (R. Arwood, pers. comm. 2013c). The vast
majority of Florida bonneted bat calls (721 of 747) were recorded at
one pond in a remote area of BCNP, with activity found on 8 of 10
nights in May and June 2013 (R. Arwood, pers. comm. 2013c). It is
noteworthy that in each of the seven locations, Florida bonneted bat
calls were not detected on the first night of sampling. Had surveys not
been conducted over multiple nights, presence would not have been
detected.
(2) Surveys in the Everglades Region
Acoustical surveys conducted on 80 nights in the Everglades region
from October 2011 to November 2012 by Skip Snow (pers. comm. 2012b,
2012c-f; in litt. 2012) documented presence at several locations within
ENP and surrounding locations (see Table 1). These findings are
significant because the importance of the Everglades region to the
Florida bonneted bat had been previously in question.
(3) Other Isolated Studies
Avon Park Air Force Range (APAFR)--An acoustical survey was
initiated at APAFR in January 2013. Surveys were conducted at 13
locations over 119 survey nights (sunset to sunrise) (B. Scofield,
pers. comm. 2013f). As of August 2013, a total of 9 Florida bonneted
bat call sequences (of 2,170 total bat call sequences) were recorded at
two locations on APAFR in Polk County (B. Scofield, pers. comm. 2013a-
f). At one location, presence was detected in scrubby flatwoods within
a red-cockaded woodpecker colony next to a natural open water lake/pond
(B. Scofield, pers. comm. 2013b). At the second location, presence was
detected near a wetland embedded in scrub habitat about 4.0 km (2.5 mi)
from the previous detection (B. Scofield, pers. comm. 2013e). These
findings are significant because they provide additional evidence of
current presence in the northern part of the species' range, where
survey information is generally lacking. It is also noteworthy that at
one location detected, Florida bonneted bats were not recorded for the
first 3 weeks of sampling (B. Scofield, pers. comm. 2013d). Had surveys
not been conducted over multiple weeks at the same location, presence
may not have been detected.
Florida Panther NWR--An acoustical survey was conducted at Florida
Panther NWR from February 28 to May 5, 2013. Surveys using multiple
detectors were conducted at 13 locations on the refuge, primarily near
water bodies, over 57 survey nights (Maehr 2013, pp. 5-7; C. Maehr,
pers. comm. 2013b). The number of detection devices deployed at each
location ranged from 4 to 9, depending upon size and access to open
water (Maehr 2013, pp. 5-7). Recordings were taken for 3 to 4
consecutive nights at each location, with all frequencies recorded from
dusk plus 7 hours (Maehr 2013, p. 5). Florida bonneted bats calls were
recorded at 9 of 13 locations, primarily in areas of the largest open
water and in the area of the Fakahatchee Strand that bisects the refuge
(Maehr 2013, pp. 7-9).
This study confirms presence on the refuge and suggests that it is
an important area for the species. Of additional significance was the
simultaneous recordings of Florida bonneted bats at multiple locations
(Maehr 2013, p. 9). These findings, along with detection shortly after
sunset, suggest that Florida bonneted bats may be roosting on the
refuge, in addition to using the area for foraging (Maehr 2013, p. 9).
Additional data analyses are currently underway. Detections at numerous
locations may be partly attributable to the comprehensive array of
detectors deployed (e.g., saturation of specific sites), multiple
nights sampled, and length of hours sampled (i.e., 7 hours or more each
night).
Zoo Miami, Larry and Penny Thompson Park, and Martinez Preserve--An
acoustical survey of the properties, totaling roughly ~526 ha (~1,300
ac), was conducted using a grid system and randomized sampling points
(F. Ridgley, pers. comm. 2013a-c). As of June 2013, 137 nights of
recordings have been conducted, with recordings taken from dusk to dawn
and microphones elevated on a portable 5.2-m (17-ft) mast (F. Ridgley,
pers. comm. 2013b). Results of the first quarter analysis yielded 154
Florida bonneted bat calls out of over 20,500 total bat call sequences
(F. Ridgley, pers. comm. 2013b). The species was detected at 23 of the
50 sampling points; 10 of those points accounted for more than 80
percent of the calls (F. Ridgley, pers. comm. 2013b). Peak activity
areas for the Florida bonneted bat within the study area are associated
with artificial freshwater lakes adjacent to intact pine rockland (F.
Ridgley, pers. comm. 2013b). Although no roosting sites have been
identified to date, early emergence calls (within 15-20 minutes after
sunset) have been repeatedly documented, and all early calls have been
on the edge of a tract of intact pine rockland (F. Ridgley, pers. comm.
2013b).
In summary, the Florida bonneted bat appears to be largely
restricted to south and southwest Florida. The core range may primarily
consist of habitat within Charlotte, Lee, Collier, Monroe, and Miami-
Dade Counties. Recent data also confirm use of portions of south-
central Florida in Okeechobee and Polk Counties and suggest possible
use of areas within Glades County. However, given limited available
data, it is not clear to what extent areas outside of the core range
may be used. It is possible that areas outside of the south and
southwest Florida are used only seasonally or sporadically.
Alternatively, these areas may be used consistently, but the species
was not regularly located due to limited search efforts, imperfect
survey methods, constraints of recording devices, and general
difficulties in detecting the species.
Population Estimates and Status
Historical--Little information exists on historical population
levels. Details are provided in the proposed listing rule (77 FR
60750).
Current--Based upon available data and information, the Florida
bonneted bat occurs within a restricted range and in apparent low
abundance (Marks and Marks 2008a, p. 15; 2012, pp. 9-15; Timm and
Arroyo-Cabrales 2008, p. 1; FWC 2011a, pp. 3-4; FWC 2011b, pp. 3, 6; R.
Timm, pers. comm. 2012, in litt. 2012). Actual population size is not
known, and no population viability analyses are available (FWC 2011a,
p. 4; 2013, p. 16; K. Bohn, in litt. 2012). However, population size is
thought to be less than that needed for optimum viability (Timm and
Arroyo-Cabrales 2008, p. 1; K. Bohn, in litt. 2012). As
[[Page 61012]]
part of their evaluation of listing criteria for the species, Gore et
al. (2010, p. 2) found that the extent of occurrence appears to have
decreased on the east coast of Florida, but trends on the west coast
could not be inferred due to limited information.
In his independent review of the FWC's biological status report,
Ted Fleming, Emeritus Professor of biology at University of Miami,
noted that anecdotal evidence from the 1950s and 1960s suggests that
this species was more common along Florida's southeast coast compared
with the present (FWC 2011b, p. 3). Fleming stated that, ``There can be
no doubt that E. floridanus is an uncommon bat throughout its very
small range. Its audible echolocation calls are distinctive and easily
recognized, making it relatively easy to survey in the field'' (FWC
2011b, p. 3). He also stated that he does not doubt that the total
State population numbers ``in the hundreds or low thousands'' (FWC
2011b, p. 3).
Similarly, in response to a request for information as part of the
Service's annual candidate notice of review, Robert Timm (pers. comm.
2012), Curator of Mammals at the Department of Ecology and Evolutionary
Biology and Biodiversity Institute at the University of Kansas,
indicated that numbers are low, in his view, as documented by survey
attempts: ``Eumops are very obvious bats where they occur because of
their large size and distinctive calls. Given the efforts to locate
them throughout southern Florida, if they were there in any significant
numbers, they would have been located'' (R. Timm, pers. comm. 2012).
Results of the 2006-2007 rangewide survey suggested that the
Florida bonneted bat is a rare species with limited range and low
abundance (Marks and Marks 2008a, p. 15). Based upon results of both
the rangewide study and survey of select public lands, the species was
found at 12 locations (Marks and Marks 2008b, p. 4), but the number and
status of the bat at each location are unknown. Based upon the small
number of locations where calls were recorded, the low numbers of calls
recorded at each location, and the fact that the species forms small
colonies, Marks and Marks (2008a, p. 15) stated that it is possible
that the entire population of Florida bonneted bats may number less
than a few hundred individuals.
Results of the 2010-2012 surveys and additional surveys by other
researchers identified new occurrences within the established range
(i.e., within Miami area, areas of ENP and BCNP) (S. Snow, pers. comm.
2011a, 2011b, 2012b-f; R. Arwood, pers. comm. 2012a, 2013a-c; Marks and
Marks 2012, p. 8), however, not in sufficient numbers to alter previous
population estimates. In their 2012 report on the status of the
species, Marks and Marks (2012, p. 12) provided an updated estimation
of population size, based upon 120 nights of surveys at 96 locations
within peninsular Florida, results of other known surveys, and personal
communications with others involved in Florida bonneted bat work. Based
upon an average colony size of 11 and an estimated 26 colonies within
the species' range, researchers estimated the total Florida bonneted
bat population at 286 bats (Marks and Marks 2012, pp. 12-15).
Researchers acknowledged that this was to be considered a rough
estimate, intended as a starting point and a basis for future work
(Marks and Marks 2012, p. 12).
In a vulnerability assessment, the FWC's biological status review
team determined that the species met criteria or listing measures for
geographic range, population size and trend, and population size and
restricted area (Gore et al. 2010, pp. 1-2). For population size and
trend, the review team estimated <100 individuals known in roosts, with
an assumed total population of mature individuals being well below the
criterion of fewer than 10,000 mature individuals. Similarly, for
population size and restricted area, the review team estimated <100
individuals of all ages known in roost counts, inferring a total
population to number fewer than 1,000 mature individuals, and
potentially three subpopulations in south Florida. Detection of the
species in the northern part of its range may be suggestive of an
additional subpopulation in south-central Florida (see Current
Distribution, above). In total, there may be three or four
subpopulations.
Similarly, the 2012 IUCN Red List of Threatened Species lists the
species as ``critically endangered'' because ``its population size is
estimated to number fewer than 250 mature individuals, with no
subpopulation greater than 50 individuals, and it is experiencing a
continuing decline'' (Timm and Arroyo-Cabrales 2008, p. 1). The FNAI
(2013, pp. 25, 29) also considers the global element rank of the
Florida bonneted bat to be G1, meaning it is critically imperiled
globally because of extreme rarity (5 or fewer occurrences, or fewer
than 1,000 individuals) or because of extreme vulnerability to
extinction due to some natural or manmade factor.
Estimates of population size are crude, relative, and largely based
upon expert opinions and inferences from available data. Due to the
numerous challenges associated with censusing bats (Kunz 2003, pp. 9-
17), it will likely be difficult to accurately estimate the size of the
Florida bonneted bat population (FWC 2013, p. 13). Alternative
approaches, such as occupancy modeling and analysis of genetic
diversity, may provide better estimates and more useful information
about population size in the future (K. Gillies, in litt. 2012; FWC
2013, p. 16).
Acoustical Survey Efforts as Indicators of Rarity
A detailed discussion of acoustical survey effort and results can
be found in the proposed listing rule (77 FR 60750). Only new
information we received during the public comment period or relevant
findings are provided below.
Results from acoustical surveys conducted in late 2012 through mid-
2013 detected generally few Florida bonneted bat calls in BCNP, except
for one location. In 296 nights of sampling, 747 Florida bonneted bat
calls of 36,441 total bat calls were recorded on 17 nights at 7 of 44
sites surveyed (R. Arwood, pers. comm. 2013c). Most of the positive
calls (721) were recorded at one location (R. Arwood, pers. comm.
2013c). Although it is difficult to compare studies, these results
appear to confirm previous findings suggesting rarity, particularly
because this study employed longer recording intervals (i.e.,
continuous recordings taken from sunset to sunrise) with multiple
nights at each site survey site (R. Arwood, pers. comm. 2012b).
Acoustical surveys conducted at Zoo Miami and adjacent pinelands
over 137 nights of sampling detected 154 Florida bonneted bat calls out
of over 20,500 bat call sequences recorded (F. Ridgley, pers. comm.
2013). Although difficult to compare to other studies, it should be
noted that this study also employed long recording intervals (i.e.,
continuous recordings taken from sunset to sunrise) taken from an
elevated microphone to improve detection.
Available data and information (from previous efforts and those
presented above) show comparatively few positive Florida bonneted bat
calls recorded relative to other bat species with considerable survey
effort expended. Although acoustical data suggest general rarity, it is
not possible to estimate population size from this information, due to
the limitations of the studies (e.g., large areas not surveyed, surveys
primarily conducted on public lands, lack of randomization in selecting
survey sites, short duration of many listening periods) and equipment
(e.g., recording distance), and aspects of the
[[Page 61013]]
species' ecology (e.g., able to fly high and travel far distances).
Occupied and Potential Occupied Areas
The Florida bonneted bat has been recorded in various habitat types
and locations in south and southwest Florida (see Table 1 and Habitat,
above) (R. Arwood, pers. comm. 2008a, 2008b, 2012a, 2013a-d; Marks and
Marks 2008a, pp. 13-14; 2008b, pp. 2-5; 2008c, pp. 1-28; 2012, pp. 1-
22; Smith 2010, pp. 1-4; S. Snow, pers. comm. 2011a, 2011b, 2012b-h; in
litt. 2012; M. Owen, pers. comm. 2012, 2012b; R. Rau, pers. comm. 2012;
Maehr 2013, pp. 1-13; S. Maehr, pers. comm. 2013a-c; K. Relish, pers.
comm. 2013; F. Ridgley, pers. comm. 2013a-c; B. Scofield, pers. comm.
2013a-f; K. Smith, pers. comm. 2013). Still, no actual colony locations
or roost sites other than occupied bat houses are currently known, and
large information gaps in the species' ecology currently exist.
Roosting and foraging behavior and habitat are not fully understood. It
is not known how far individuals travel from roosting locations to
forage or to fulfill other needs. Dietary requirements, colony
composition, movement between roosts or among colonies, and many other
basic aspects of the species' life history are poorly understood.
Despite these uncertainties, there is evidence that the species
occupies at least portions of five south and southwest Florida counties
(Charlotte, Lee, Collier, Monroe, and Miami-Dade Counties) within the
core of its range as explained below. In addition, there is additional
evidence that the species occupies portions of south-central Florida
(Polk and Okeechobee Counties) (Marks and Marks 2008b, pp. 2, 5; 2008c,
pp. 11, 17; B. Scofield, pers. comm. 2013a-f). Areas adjacent to or
near these locations may also be occupied.
Core Areas
Charlotte County
Babcock-Webb WMA--Florida bonneted bats have consistently used this
area since 2008 (J. Myers, pers. comm. 2013). The colonies at Babcock-
Webb WMA are the only known roosts on public lands and effectively
tripled the number of known active colonies (N. Douglass, pers. comm.
2009). The 33 individuals recorded in 2009 appeared to be the largest
single discovery of the species recorded in recent years (N. Douglass,
pers. comm. 2009). In 2010, monitoring by FWC indicated approximately
25 individuals at 2 additional bat houses, bringing the potential total
at Babcock-Webb WMA to 58 individuals, occupying 4 roosts (J.
Birchfield, pers. comm. 2010). In 2012-2013, periodic simultaneous
counts conducted on 4 occasions showed 39 to 43 individuals using 3 to
5 separate roosts (all bat houses) (J. Myers, pers. comm. 2013). In
addition, FWC biologists report also hearing Florida bonneted bat calls
in the vicinity of red-cockaded woodpecker cavity trees on site (J.
Myers, pers. comm. 2012a). The species is likely also using natural
roosts sites within the area (Marks and Marks 2012, pp. 13, 15; P.
Halupa, pers. obs. 2013; M. Knight, pers. comm. 2013).
Babcock Ranch Preserve--Florida bonneted bat calls recorded at
Telegraph Swamp at Babcock Ranch Preserve in 2007 are believed to
represent separate colonies from those at Babcock-Webb WMA (Marks and
Marks 2008a, p. A9; 2012, p. 13).
Other Potential Areas--The FDEP also suggested that the species may
occur at Charlotte Harbor Preserve State Park (P. Small, pers. comm.
2012).
Lee County
North Fort Myers--Florida bonneted bats have continually used bat
houses on one private property since December 2002 (S. Trokey, pers.
comm. 2006a, 2012a, 2013; Marks and Marks 2008a, p. 7). This was the
first record of this species using a bat house as a roost and the only
known location of an active colony roost located on private land (S.
Trokey, pers. comm. 2006a; Marks and Marks 2008a, pp. 7-15). The colony
had included approximately 20 to 24 individuals in 2 houses (S. Trokey,
pers. comm. 2008a, 2008b), but only 10 remained by April 2010, after
the prolonged cold temperatures in January and February 2010 (S.
Trokey, pers. comm. 2010a-c) (see also Summary of Factors Affecting the
Species, Factor E, below). In May 2011, 20 Florida bonneted bats were
found using this site (S. Trokey, pers. comm. 2011). In February 2012,
18 individuals were found (S. Trokey, pers. comm. 2012a), and in March
2013, 20 individuals were found (S. Trokey, pers. comm. 2013).
Other Potential Areas--Florida bonneted bat calls have also been
heard elsewhere in the rural North Fort Myers area, approximately 6 to
8 km (4 to 5 mi) south of Babcock-Webb WMA (S. Trokey, pers. comm.
2013).
Collier County
Naples--Available data from a single fixed site suggest that the
species is present in the area (R. Arwood, pers. comm. 2008a; Marks and
Marks 2008a, p. 11; 2012, p. 13).
Florida Panther NWR--In 2013, Florida bonneted bats calls were
recorded at 9 of 13 locations, primarily in areas of the largest open
water and in the area of the Fakahatchee Strand that bisects the refuge
(Maehr 2013, pp. 7-9; S. Maehr, pers. comm. 2013a-c).
FSPSP--Florida bonneted bat calls have been heard and recorded
throughout the year from several locations and habitat types within the
FSPSP from 2000 to present (Marks and Marks 2008a, pp. 6, 11; M. Owen,
pers. comm. 2012a, 2012b; R. Rau, pers. comm. 2012; K. Relish, pers.
comm. 2013).
PSSF--Florida bonneted bats have been detected at nine locations
within PSSF (K. Smith, pers. comm. 2013). A juvenile male was captured
in a mist net above a canal in PSSF in 2009, but no other Florida
bonneted bats were captured during additional trapping efforts (14 trap
nights) (K. Smith, pers. comm. 2010; Smith 2010, p. 1). In addition to
the captured individual, the species was heard while mist netting at
eight other locations (K. Smith, pers. comm. 2013).
BCNP--Calls have been recorded at various locations by multiple
parties (R. Arwood, pers. comm. 2008b, 2012a, 2013a-d; Marks and Marks
2008a, pp. 11, A12-A14; 2012, pp. 13-14; S. Snow, pers. comm. 2012g).
Survey efforts from 2003 and 2007 by one contractor recorded presence
at several locations (S. Snow, pers. comm. 2012g). However, results of
the rangewide survey in 2006-2007 recorded only one call at Deep Lake
in 12 nights of surveys (R. Arwood, pers. comm. 2008b; Marks and Marks
2008a, pp. 11, A12-A14). In 2012, five calls were recorded at Cal
Stone's camp during 2 nights of surveys (R. Arwood, pers. comm. 2012a;
Marks and Marks 2012, pp. 13-14). Presence was also recorded at seven
locations within BCNP in late 2012 through mid-2013 (R. Arwood, pers.
comm. 2013a-d). This latter study employed longer listening intervals
and multiple survey nights at each site (R. Arwood, pers. comm. 2012b).
Everglades City--Available data suggest that the species is present
in the area (R. Arwood, pers. comm. 2008a; Marks and Marks 2012, p.
14).
Ten Thousand Islands area--The Florida bonneted bat was detected at
Dismal Key in Ten Thousand Islands NWR in 2000 (Timm and Genoways 2004,
p. 861; B. Nottingham, pers. comm. 2006; T. Doyle, pers. comm. 2006; C.
Marks, pers. comm. 2006c; Marks and Marks 2008a, p. 6). Calls were not
recorded during the 2006-2007 survey in areas searched by boat from
Dismal Key to Port of the Islands (Marks and Marks 2008a, pp. 11, 14,
A9). However, Florida bonneted bat calls
[[Page 61014]]
were reportedly heard by a volunteer at Port of the Islands (R. Arwood,
pers. comm. 2012b).
Other Potential Areas--In November 2007, the species was observed
along U.S. 41 at Collier-Seminole State Park (S. Braem, pers. comm.
2012). The FDEP also suggested that the species may occur at Delnor-
Wiggins Pass State Park (P. Small, pers. comm. 2012).
Monroe County
ENP (coastal)--In 2012, only one Florida bonneted bat call was
recorded at Darwin's Place in ENP in 18 survey nights in areas searched
from Flamingo to Everglades City (Marks and Marks 2012, pp. 8, 14,
A50). Darwin's Place is approximately 4.8 km (3 mi) from Watson's
Place, where another researcher (Laura Finn, Fly-By-Night) had recorded
10 Florida bonneted bat calls in 2007 (Marks and Marks 2012, p. 14; S.
Snow, pers. comm. 2012h).
Other Potential Areas--Other coastal and remote areas within ENP
may support the species; however, additional surveys are needed.
Miami-Dade County
ENP (mainland)--Acoustical surveys conducted on 80 nights from
October 2011 to November 2012 by Skip Snow (pers. comm. 2012b-f; in
litt. 2012) documented presence at several locations within ENP and
surrounding locations (see Table 1). Results of the 2006-2008 survey
did not detect Florida bonneted bat calls in the Long Pine Key area,
which was thought to be the most likely location for the species (Marks
and Marks 2008a, p. 10; 2012, p. 14). However, the species was
subsequently recorded in the Long Pine Key area in 2011 and 2012 (S.
Snow, pers. comm. 2011a, 2012f; in litt. 2012; Marks and Marks 2012,
pp. 8, 14, 17).
Homestead area--Calls recorded in the Homestead area in 2006 and in
2008 suggest that one colony exists, possibly located east of U.S. 1
(Marks and Marks 2008a, pp. 11, A6-A7; 2008b, p. 5; 2012, p. 14).
Coral Gables and Miami area--Florida bonneted bat calls have been
consistently recorded in acoustical surveys at the Granada Golf Course
in Coral Gables, but not elsewhere in the vicinity (Marks and Marks
2008a, p. 6, A4; 2008b, pp. 1-6; 2012, p. 14). Since calls were
recorded so shortly after sunset, the species may be roosting on or
adjacent to the golf course (Marks and Marks 2012, p. 14). Calls
recorded at Snapper Creek Park in south Miami in 2008, Zoo Miami in
2011-2013, Larry and Penny Thompson Park and Martinez Preserve in 2012
and 2013, FTBG in 2011 and 2012, and the L31-N canal in 2012 suggest
that colonies are at or near these locations (Marks and Marks 2008b,
pp. 1-2; 2012, pp. 1-22 and appendices; S. Snow, pers. comm. 2011b,
2012b-f; Ridgley 2012, p. 1; F. Ridgley, pers. comm. 2013a-c). At Zoo
Miami and Larry and Penny Thompson Park, all early evening calls have
been recorded at the edge of a tract of intact pine rockland (F.
Ridgley, pers. comm. 2013b).
Other Potential Areas--Other undeveloped areas within the Richmond
Pinelands likely also provide habitat (J. Maguire, in litt. 2012).
These may include Federal land holdings (i.e., owned by the U.S. Coast
Guard, the U.S. Army, and General Services Administration), large
parcels owned by the University of Miami, or other areas (J. Maguire,
in litt. 2012).
Non-Core Areas
Polk County
KICCO WMA--Florida bonneted bat calls were recorded along the
Kissimmee River in in May 2008 (Marks and Marks 2008b, p. 2; 2008c, pp.
11, 17). Documented presence along the Kissimmee River was significant
as this was the first time the species had been detected north of Lake
Okeechobee, except in fossil records, and effectively extended the
known range 80 km (50 mi) north (Marks and Marks 2008b, pp. 2, 5;
2008c, pp. 1-28).
APAFR--Florida bonneted bat calls were recorded at two of 13
locations on APAFR in 2013 (B. Scofield, pers. comm. 2013a-f). These
findings are significant because they provide additional evidence of
current presence in the northern part of the species' range, where
survey information is generally lacking.
Other Potential Areas--Areas along the Kissimmee or other areas
within Polk County (and possibly adjacent counties) may support the
species; however, additional surveys are needed.
Okeechobee County
Kissimmee River Public Use Area--Florida bonneted bat calls were
recorded at Platt's Bluff along the Kissimmee River in Okeechobee
County in May 2008 (Marks and Marks 2008b, p. 2; 2008c, pp. 11, 17).
Other Potential Areas--Areas along the Kissimmee River or other
areas within Okeechobee County (and possibly adjacent counties) may
support the species; however, additional surveys are needed.
Summary of Comments and Recommendations
In the proposed rule published on October 4, 2012 (77 FR 60750), we
requested that all interested parties submit written comments on the
proposal by December 3, 2012. We also contacted appropriate Federal and
State agencies, scientific experts and organizations, and other
interested parties and invited them to comment on the proposal. Notices
inviting general public comment were published in the following Florida
newspapers: The Miami Herald, Naples Daily News, Orlando Sentinel, The
Palm Beach Post, The News-Press (based in Fort Myers), Charlotte Sun
and Englewood Sun (based in Charlotte County), and The Ledger (based in
Lakeland) on Sunday, October 14, 2012. We did not receive any requests
for a public hearing.
During the comment period for the proposed rule, we received 37
comment letters (from 39 entities) directly addressing the proposed
listing of the Florida bonneted bat as an endangered species, including
the finding that critical habitat was prudent, but not determinable.
With regard to listing the Florida bonneted bat as an endangered
species, 28 comments were in support, four were in opposition, and five
were neutral. With regard to critical habitat, five comment letters
expressed opinions. Of these, three peer reviewers stated that more
information was needed to determine critical habitat, and two
environmental groups indicated that such designation should be a timely
goal or completed promptly. All substantive information provided during
the comment period has either been incorporated directly into this
final determination or is addressed below.
Peer Review
In accordance with our peer review policy published on July 1, 1994
(59 FR 34270), we solicited expert opinion from 10 individuals with
recognized expertise on bats, particularly molossids, as well as
general expertise on bat ecology and conservation. We received
responses from six of the peer reviewers.
We reviewed all comments we received from peer reviewers for
substantive and new information regarding the listing of the Florida
bonneted bat as an endangered species. The peer reviewers generally
concurred with our methods and conclusions, and provided additional
information, clarifications, and suggestions to improve the final rule.
Of the six reviews we received, three reviewers commented on critical
habitat and agreed that additional information was needed to help
define critical habitat. Peer reviewer comments are addressed in the
following summary and
[[Page 61015]]
incorporated into the final rule as appropriate.
Peer Reviewer Comments
This section focuses on comments from peer reviewers and our
responses to them. However, we have also included other public comments
in this section (referred to as ``other commenters'' or ``commenters'')
if those comments were related in topic to peer reviewer comments.
Comments Related to the Species and Its Ecology
(1) Comment: One peer reviewer, who first recognized the unique
morphological and genetic population of bonneted bats in southern and
southwestern Florida merited recognition as a full species rather than
a subspecies, reconfirmed the information summarized in the proposed
rule as it related to taxonomy and stated that the Florida bonneted bat
is clearly a ``distinctive'' species. He indicated that he has
personally examined all of the specimens of the species deposited in
the world's scientific collections, and that he and his colleagues have
conducted the morphological and genetic studies comparing and
contrasting this species to other species of Eumops and other
molossids.
Another reviewer with expertise in systematics and evolutionary
biology related to mammals, who has published articles on the
evolutionary relationships of various Eumops species, also agreed with
the interpretation of literature regarding systematics, evolution, and
fossil data. She indicated that although nuclear (AFLP) and
mitochondrial data do not demonstrate a distinct genetic signature when
compared to Eumops from the Caribbean, the cranial and bacular (penile
bone) morphology indicate that Eumops from Florida are unique and
therefore merit specific status. She further suggested that genetic
distances indicate that E. floridanus is a recent species, and this is
confirmed by fossil evidence from the Pleistocene.
This reviewer also provided a Master's thesis (Bartlett 2012, pp.
1-33), which examined additional mitochondrial and nuclear data for the
genus, but did not include additional nuclear data for E. floridanus.
She indicated that the mitochondrial data in this thesis demonstrated
the same results as those found in McDonough et al. 2008 that support
E. floridanus having a similar mitochondrial DNA sequence signature as
those from the Caribbean. In her view, the signature was likely a
result of incomplete lineage sorting in the mitochondrial genomes of
Eumops from the region and represented recently diverged taxa.
Eight other commenters also indicated that the species is
``evolutionarily distinct'' and ``unique enough to be considered a
separate species.''
Our Response: We appreciate the reviewers' confirmation that Eumops
floridanus is unique and continue to affirm that the taxon is distinct
at the species level, based upon the best scientific information
available and peer review of that information. We acknowledge the
recent thesis (Bartlett 2012, pp. 1-33) and subsequent paper (Bartlett
et al. 2013, pp. 867-880), but they do not alter our conclusions.
Bartlett (2012, p. 13) and Bartlett et al. (2013, pp. 875-876)
acknowledged that E. floridanus is distinguished from other members of
the E. glaucinus complex based upon several features as described by
Timm and Genoways (2004). However, based upon examination of the
cytochrome-b dataset, researchers found a low level of sequence
divergence among and between E. ferox and E. floridanus and incomplete
separation of the two species; therefore, researchers suggested
reevaluation of E. floridanus as a valid species. Additional
morphological and genetic studies comparing and contrasting E.
floridanus to other species of Eumops and other molossids will provide
further insights into their relationships and phylogenies.
(2) Comment: One reviewer stated that the Florida bonneted bat's
life history is very poorly understood and emphasized that a critical
factor to understand is reproductive approach. The reviewer stated that
it is imperative to determine if the species is indeed polyestrous, as
speculated. She also underscored the need to determine other metrics,
such as genetic diversity and roosting ecology, in order to prioritize
conservation measures in a recovery plan.
Another reviewer stated that low reproductive rate and other
factors (discussed below) make extinction highly probable. Nine
commenters also expressed concern over low fecundity or slow population
growth.
Our Response: We agree that the life history of the species is
poorly understood, and that determining the species' reproductive
approach and other aspects of its life history and ecology (e.g.,
longevity, colony sizes, foraging and roosting preferences) will be
essential to minimizing threats and conserving the species and its
habitat. The FWC recently funded a large multi-year study that is
expected to close some of the data gaps for the Florida bonneted bat.
The ultimate goal of the study is to gain a better understanding of
aspects of the Florida bonneted bat's biology to enable the development
of recommendations for additional conservation measures for the species
(Ober and McCleery 2012, p. 2). We believe this new study and other
research will provide important data and insights and greatly aid in
conservation of the species and its habitat.
(3) Comment: Three reviewers and 11 commenters in support of the
listing expressed concern over the species' restricted geographic range
as a factor contributing to its imperilment. One reviewer stated that
the Florida bonneted bat has the most restrictive range of any bat in
the United States and suggested that a single storm (such as Hurricane
Sandy) could kill most of the individuals over a fairly broad area.
Another reviewer acknowledged the species' extremely restricted range,
but disagreed with the statement that the Florida bonneted bat has the
most restricted range of any Florida mammal.
One reviewer stated that our understanding of the distribution of
the species is extremely limited due to shortcomings of the surveys
conducted to date and the high degree of variability in the temporal
component of the survey effort. In her view, our proposed rule
suggested that it is easy to survey through acoustical means; she
emphasized that although the calls are distinctive, the short-duration
listening intervals of many surveys may erroneously conclude that an
area is not being used. Since bat activity can vary greatly at a single
location both within and between nights (Hayes 1997, pp. 514-524; 2000,
pp. 225-236), a lack of calls during a short listening period may not
be indicative of lack of use. The variable duration of the listening
periods of past surveys makes it difficult to make conclusions about
changes in occupancy or activity levels over time and space.
Another reviewer emphasized that the extent of the species' range
must be determined to mitigate potential impacts from land use
activities and to identify areas for priority conservation.
Eight commenters in support of the proposed listing also noted that
the species is ``geographically isolated.''
Some in opposition to the proposed listing offered other views. One
commenter noted that the recent surveys have documented the species in
at least seven Florida counties, suggesting a range expansion. Another
commenter indicated that the species' range is larger than previously
understood and suggested additional surveys. The same commenter
suggested
[[Page 61016]]
that range ``be properly defined'' through additional surveys in rural
areas containing habitat similar to those areas where sightings have
been recorded and that surveys be conducted over as many as 10 nights
per survey region. The same commenter also suggested that a survey
using Florida bonneted bat-optimized bat houses erected in strategic
locations could also provide data related to the range east and west of
the Kissimmee River basin. Another commenter did not think there was
enough survey information available to establish range.
One commenter, who did not express an opinion on the listing
action, recommended that the Service design an echolocation survey
protocol based on the best scientific data that defines survey seasons,
duration of surveys, methodology, number of survey periods, and types
of data to be collected. He recommended that the Service require
surveys to be conducted in the core range prior to construction in
natural habitats. In his view, additional echolocation data would
provide evidence of presence/absence and that continued surveys over
time in different locations would provide additional information on the
species' distribution and habitat utilization. Mist netting was also
suggested in combination with echolocation surveys.
Our Response: Our understanding of the species' distribution, as
well as its abundance, biology, and habitat preferences, would benefit
from additional survey information and research. We acknowledge that
the surveys conducted to date have been limited in scope and
inconsistent in methods used. More robust study designs would account
for sources of temporal, spatial, and sampling variation (Hayes 2000,
pp. 225-236). Longer surveys at more locations over additional nights
and seasons using more consistent methods would undoubtedly contribute
to increasing understanding. Surveys that are longer in duration (e.g.,
conducted throughout the entire night) and repeated over several nights
would help add confidence regarding potential use of an area. We note
that some of the most recent studies (see Other Isolated Studies,
above) are employing or have used such methods. Additional surveys
along peripheral portions of the range could help to better define
occupancy. See also Comment 4 and our response, below.
In an effort to acquire more information, the Service purchased
five acoustical recording devices in 2012, and we are working with
numerous partners (BCNP, ENP, APAFR, FSPSP, FWC, Miami Zoo, FBC) to
obtain and analyze additional data. For example, we are attempting to
collect additional data along the northern extent of the species' known
range; this could help determine if portions of Polk and Okeechobee
Counties should also be considered part of the species' core range.
Additional data from this area are key to determining if this is an
apparent expansion of the species' known range. Recording devices are
also being used in more places for longer periods of time over multiple
nights in BCNP (see above, R. Arwood, pers. comm. 2013a-d). A new
acoustical study was also conducted at the Florida Panther NWR, with
the help and support of other NWRs in the southeast. We believe the
additional data from multiple sources will be useful in better defining
range and key to better understanding the species' biology, relative
abundance, and habitat preferences.
Although previous surveys have limitations, there is ample
scientific evidence to indicate that the Florida bonneted bat has a
very restricted range, perhaps one of the most restricted of any bat in
the United States. We have made clarifications to the text regarding
range and have more thoroughly discussed the limitations of surveys
accordingly. The data indicate that the species' limited range
contributes to its imperilment; some threats (e.g., hurricanes, climate
change) have the potential to have severe consequences on the species
and its habitat in a single widespread or regional event.
We agree that an acoustical survey protocol or broader survey
guidelines for the Florida bonneted bat should be established, and we
intend to work towards that in cooperation with partners. A well-
defined protocol with consistent and repeated surveys, in combination
with other studies, would help to better understand distribution,
relative abundance, biology, and habitat preferences. See also Comment
4 and our response, below.
(4) Comment: Three peer reviewers and 13 commenters in support of
the listing expressed concern over the apparent rarity or small
population size as a factor contributing to its imperilment. Although
the minimum viable population size is not known, one reviewer predicted
a ``strong Allee effect'' (decline in individual fitness) at low
population sizes due to at least two factors. First, offspring survival
in bats is usually highly correlated with maternity colony size due to
thermoregulation, and colony sizes for this species are relatively
small. Thus, low survival is expected if females are roosting
solitarily or in numbers fewer than 10 individuals. Second, roost sites
function as information centers for many species of bats (e.g., the
velvety free-tailed bat (Molossus molossus), see Dechmann et al. 2010).
The reviewer's observations of one Florida bonneted bat colony
suggested that the species is highly social, much like Brazilian free-
tailed bats (Bohn et al. 2008, pp. 1838-1848), which may have an effect
on viability at low population sizes.
One reviewer acknowledged that the Service and its partners may be
unable to confidently estimate a population size for the Florida
bonneted bat and noted that challenges arise when trying to estimate
population size for organisms that are ``cryptic, volant, elusive,
rare, and highly mobile.'' She suggested that when detection
probabilities are exceptionally low, erroneous population estimates and
trends may result. Her recommendation was to use alternate approaches,
including patch occupancy models, which are more appropriate tools for
estimating distribution trends.
Another reviewer did not believe that population estimates could be
derived from available data. In her view, there is no way to
extrapolate from surveys conducted along roads to areas without roads
that were not surveyed or from conservation areas that were surveyed to
private agricultural areas that were not surveyed. She specifically
indicated that due to the immense areas that were not surveyed, the
short duration of many listening periods, and the lack of randomization
when selecting survey sites, it could not be said that ``it is not
likely that abundance is appreciably larger than the current available
population estimates given.''
Other commenters in opposition to the proposed listing offered
different views. One commenter objected to listing the species as
endangered due to the lack of good population studies. He argued that
with no known roosting areas and just a few known sightings, there was
not enough evidence to declare the bat endangered. One commenter
indicated that it is difficult to have a reliable estimate of current
population, given the limitations of sampling, including limitations in
detection from ultrasonic devices and the high-flying habits of the
species. This commenter endorsed the suggestion provided by another
commenter who had recommended that the Service design an echolocation
survey protocol. Another commenter stated that the surveys cannot be
used to establish abundance or range, due to so few surveys being
conducted, surveys mainly being conducted in open areas,
[[Page 61017]]
and the vast areas of potential habitat that have not been surveyed.
Another commenter indicated that the population size for the
Florida bonneted bat is much larger than originally estimated based
upon 12 new sightings since 2008. The same commenter used the new
information to negate criteria used within the State's biological
status review, suggesting that data were ignored. This commenter
suggested that the survey intensity for many parts of Florida were
insufficient, and that every time a survey has been performed
additional sightings have been recorded in new locations.
Our Response: We acknowledge that the survey information available
to date is limited in many regards, and that it is not possible to
estimate population size on this information alone. We have added
clarifications regarding the limitations and short-comings of the
acoustical surveys and have re-examined how we use this information. It
was not our intent to imply that population estimates were derived
purely or directly from acoustical surveys. We have made adjustments to
the text and tried to more clearly articulate that the population
estimates are only relative numbers of abundance, largely based upon
expert opinions and inferences from available data. We are unable to
confidently estimate population size for this species at this time.
Our understanding of the species' abundance, as well as its
distribution, biology, and habitat preferences, would benefit from
additional survey information and research (see Comment 3 and our
response, above). We agree that it would be beneficial to use patch
occupancy models and other approaches to estimating distribution
trends. We agree that it would be helpful to have more randomized
surveys, longer listening periods, more areas surveyed, and repeated
surveys. We intend to work with our partners on an acoustical survey
protocol design, which if employed consistently, could improve the
quality of information obtained in the future.
The best available scientific information and the majority of
expert opinions indicate that the Florida bonneted bat population is
relatively small (see Population Estimates and Status and Acoustical
Survey Efforts as Indicators of Rarity, above) and the species'
apparent low abundance is a major factor in its overall imperilment
(see Factor E, Effects of Small Population Size, Isolation, and Other
Factors, below). We have revised the above sections to clarify and
better explain uncertainty and limitations of available information.
(5) Comment: One reviewer acknowledged that the foraging behavior
of the Florida bonneted bat has not been studied in detail and provided
insights into probable foraging behavior based upon its morphology. She
stated that molossids are highly adapted for hawking high-flying
insects (Norberg and Rayner 1987) and are characterized by high aspect
ratios, high wing loadings, long pointed wingtips, and use of low
frequency narrowband echolocation calls, which collectively make them
well-suited for fast flight at high altitudes and prey detection at
long distances, relative to other bats. The reviewer pointed out that
species with these morphological features are considered to be adapted
for low cost, swift, long distance travel from roost sites to foraging
areas. In her view, these morphological characteristics and
echolocation call structure likely preclude their ability to maneuver
or detect prey at short range in cluttered conditions, given their
large turning radius and the limited information obtained through the
use of low frequency, narrowband echolocation calls. Therefore, she
surmised that it seems likely that foraging areas may be located fairly
long distances from roost sites, and that foraging likely occurs either
at high altitudes or in fairly open habitat.
Another reviewer noted that the Florida bonneted bat is a molossid,
which ``consists of high flying bats capable of dispersing great
distances''. She recommended a study that identifies home ranges and
habitat affinities to determine the physical and biological features
essential to the conservation of the species.
The NPS (ENP) commented on an effort to better understand foraging
behavior and foraging habitat. A biologist from ENP reviewed all
acoustic files available, from 2000 to present, which were identified
as belonging to the Florida bonneted bat to better understand foraging
habitat. Review of these files did not reveal any definitive ``feeding
buzzes'', a feature presumed indicative of successful foraging in other
bats. Biologists in south Florida conducting acoustical surveys were
also queried by ENP, and they confirmed that they had yet to identify a
feeding buzz attributable to the Florida bonneted bat. In this view,
the ecomorphology of the Florida bonneted bat, and Eumops spp. in
general, suggests a bat that flies high, relatively fast, and quite
possibly far. Those characteristics confound acoustic detection,
including capturing feeding events as indicated by the ``feeding
buzz.'' ENP believes that it is not unreasonable to consider that the
Florida bonneted bat may forage some of the time and perhaps frequently
at altitudes beyond the range of detection by acoustic survey
equipment.
Another commenter argued that since the species forages at heights
of 10 m (33 ft) or more, it is possible that the species forages above
canopied areas. This commenter contended that there was no information
or extensive surveys from canopied areas and that actual foraging sites
have not been scientifically determined.
Our Response: We acknowledge that the Florida bonneted bat's
dispersal capabilities, foraging behavior, habitat affinities, and home
ranges are not clearly understood. We agree that the Florida bonneted
bat is likely capable of dispersing large distances and believe it may
have considerable home ranges. For comparison, in one study in Arizona,
Underwood's mastiff bat was found to range up to 24 km (15 mi) or more
on foraging bouts from its roost site, suggesting that roost sites do
not need to be available in close proximity to foraging areas (Tibbitts
et al. 2002, p. 11). We have clarified the text accordingly (see
Background, above).
We agree that the species' morphological characteristics make it
reasonable to assume that foraging areas may be located fairly long
distances from roosts sites, and that foraging likely occurs either at
high altitudes or in fairly open habitat. We do not dismiss the idea
that foraging habitat may include canopied areas; the species may
forage above, within, or adjacent to canopied areas. We agree that the
lack of or limited number of ``feeding buzzes'' recorded to date may
further suggest that the species forages at altitudes beyond the range
of detection of acoustic survey equipment. The only set of ``feeding
buzzes'' for the species that we are aware of were recorded at the
Granada Golf Course in Coral Gables in late February 2013 (C. Marks,
pers. comm. 2013).
Additional studies are needed to more completely understand
foraging behavior and habitat preferences. In future acoustical
studies, it may be beneficial to sample vertical strata where possible,
to determine activity and obtain additional insights into habitat use
(Hayes 2000, p. 229). Placing recording devices at higher positions in
the landscape (e.g., fire towers) may be helpful in determining if
foraging is occurring at higher altitudes. Longer recording intervals,
more survey locations, and additional analysis of echolocation data may
be helpful in
[[Page 61018]]
identification of more ``feeding buzzes'' and improved understanding.
The use of tracking devices such as transmitters, if tolerated by this
species, may be extremely helpful to understanding movements, including
insights into foraging distances and behavior. We note that the FWC
recently funded a large multi-year study that is expected to close some
of the data gaps for the Florida bonneted bat, including, in part,
habitat selection. This study is expected to begin in January 2014 (H.
Ober, pers. comm. 2013). Analysis of guano will be helpful in
identifying prey items, assessing the availability of prey, and
understanding foraging habitat. At this time, we are working with
researchers and partners to conduct limited dietary analysis.
(6) Comment: One reviewer commented extensively on roost site
selection, stating that there is a high probability that Florida
bonneted bat individuals would tend towards high roost site fidelity.
She pointed to the work of Lewis (1995), who in her review, found that
bats that roost in buildings tend to be more site-faithful than those
that roost in trees, and that among the bats that roost in trees, those
that use cavities in large trees tend to more site-faithful than those
using smaller trees. Given its large size, this reviewer surmised that
the Florida bonneted bat is likely to select large trees. She noted the
large accumulation of guano in one known historical natural roost (1 m
[3.3 ft] deep) provided further evidence of high roost fidelity,
especially given the small number of individuals per colony. Although
it is not known if the species more commonly uses tree cavities or
buildings, the reviewer stated that the loss of a roost site is likely
to cause a greater hardship to the species than the loss of a roost
site for other, more labile (readily open to change) species. In her
view, the threat imposed by the loss of individual roost sites was
understated in the proposed rule.
The same reviewer noted that larger roosts tend to have greater
microclimatic variability within a roost than do smaller spaces, which
could increase the relative importance of manmade roosts to the species
as climate variability increases in the future. For example, she
suggested that bats roosting in tree cavities may need to switch roosts
in response to a cold spell, making them vulnerable to exposure,
predation, or other threats, whereas individuals using larger buildings
may be able to simply change locations within their roost. She pointed
out that the species' use of anthropogenic structures may confer an
adaptive advantage in the future and allows for the possibility of
future habitat enhancement through the creation of additional
artificial roosts with suitable characteristics, once determined.
One reviewer indicated that since so little is known about this
species' roosting habits, it is possible that palm fronds are used for
roosting. In her view, it is imperative to determine roosting ecology
and other metrics to prioritize conservation measures in a recovery
plan. Another reviewer indicated that roost sites function as
information centers for many species of bats, including the molossid,
the velvety free-tailed bat (Dechmann et al. 2010).
With regard to roosting sites, the FWC suggested clarification for
the term ``key roosting sites'' or using simply using the term
``roosting sites'' instead, indicating that there was no information to
suggest that some roosting sites may be more critical than others.
Eleven commenters in support of the listing also mentioned lack of
roosting information. Several suggested that we know less about this
species than when it was first considered for protection.
Commenters in opposition to the proposed listing offered different
views. Two commenters stated that there is not enough evidence to
declare the bat endangered when we have such limited information
regarding roosting areas or preferred roosting habitat. Another
commenter believed the species' adaptability to human structures is a
positive and questioned if the species has more roosting opportunities
now than it did historically due to development.
Our Response: We agree with views regarding roosting habits and
believe that finding natural roosting sites and better understanding
preferences is crucial to conserving the species. The Florida bonneted
bat may indeed have high roost site fidelity, as one reviewer
suggested, and the loss of any roost site for this species may have
profound consequences. We agree that it is likely that all roost sites
are important and clarified the importance of roosting sites
accordingly. See also Comment 4 and our response, above.
We agree that the species' ability to adapt to artificial
structures can be beneficial in some regards. For example, artificial
structures may provide potential suitable roost sites in areas where
natural roost sites are lacking, limited, or inadequate. However, we
caution against the mindset that artificial structures can equally
replace natural roosts. More research on the role of bat houses in the
conservation of the species is needed (FWC 2013, pp. 10-11). Artificial
structures may be more likely to be disturbed, may be more prone to
vandalism, and may or may not be maintained.
We disagree with the views opposing the listing due to lack of
information on preferred roosting habitats. Listing decisions are based
upon all available data and information and threats (see Background,
above, and Summary of Factors Affecting the Species and Determination
of Status, below). While there may be more artificial roosting
opportunities available now due to development, we do not have data
that indicate the species has more suitable roosting sites overall.
Natural roost sites have undoubtedly been lost due to changes in land
use (see Summary of Factors Affecting the Species, Factor A), and
competition for tree cavities has increased (see Summary of Factors
Affecting the Species, Factor E, Competition for Tree Cavities, and
Comment 9 and our response, below). Additionally, changes in building
codes may have reduced opportunities in some artificial structures (see
Comment 11 and our response, below).
We acknowledge that we do not fully understand roosting habitat
preferences, but we are working with partners to locate roosts and
better understand the ecology of the species. Additional acoustical
data are being collected from more sites for longer periods of time. In
February 2013, we worked with Auburn University and numerous land
managers and partners across south Florida to use trained scent
detection dogs in an effort to identify and locate potential natural
roosts. The dogs showed interest in several large cavity trees and
snags. Follow-up work (e.g., acoustical surveys, infrared cameras,
cavity inspection, guano collection) is being conducted to determine if
Florida bonneted bats or other bat species are using these trees and
snags as roosts. To date, no active, natural roosts for the Florida
bonneted bat have been confirmed.
Comments Relating to Threats
(7) Comment: Three reviewers and 11 commenters in support of the
listing remarked on habitat loss, modification, or curtailment of
range. One reviewer stated that loss of habitat, especially forested
areas, is among the most important threats. Another reviewer stated
that the loss of individual roost sites (from exclusion, demolition,
tree harvest, or other factors) was understated in the proposed rule
because of suspected high roost fidelity. Another reviewer stated that
habitat loss, degradation, alteration, and fragmentation are
significant threats; in
[[Page 61019]]
order to mitigate potential impacts from land use activities and to
identify areas for priority conservation actions, the extent of the
species' range must be determined.
One commenter, writing on behalf of an environmental group with
more than 4,000 members with a focus in southwest Florida, stated that
the species faces continued threats from habitat loss and specifically
from several proposed large-scale developments, mines, and
transportation projects. The group highlighted proposed projects in
their five-county area of focus (i.e., Lee, Collier, Hendry, Glades,
and Charlotte), stating that thousands of acres of impacts are expected
in a variety of habitat types. In Charlotte County, the group
specifically noted the Babcock Ranch Community (encompassing over
17,000 acres (ac)) and the Burnt Store Area Plan near Punta Gorda would
allow mixed use development within an area thousands of acres in size.
In Hendry County, it noted the Rodina sector plan (encompassing 26,000
ac), the King's Ranch/Consolidated Citrus sector plan (at least 15,000
ac), and the Hendry County Clean Energy Center (more than 3,000 ac). In
Lee and Collier Counties, it referenced pending and potential mines
totaling tens of thousands of acres. In this group's view, the most
significant action was the Eastern Collier Multispecies Habitat
Conservation Plan (HCP), which it stated, if permitted as proposed,
would authorize 45,000 ac of residential and commercial development.
Additionally, the group contended that an ``untold number of acres of
potential bat habitat would be lost'' to multiple land uses, including
mining, oil and gas exploration/production, agriculture,
infrastructure, transportation, and active and passive recreation. It
also noted that the Collier County Rural Lands Stewardship Program is
voluntary and does not protect some areas that may be important to
bats.
With regard to issuing permits, the same group contended that since
the Service cannot effectively determine the conservation measures
needed to conserve the species and protect it from no net loss, the
agency should not issue a take permit. Rather, it recommended that the
Service and its partners focus efforts on collecting additional
information to map essential habitat areas for this species. In this
view, only with this information could the Service properly assess
jeopardy under section 10 or section 7 of the Act. In conclusion, the
group fears ``the species is routinely placed in jeopardy''.
Another commenter, writing on behalf of its organization with more
than 450,000 members and activists, provided extensive comments on
climate change and contended that the Florida bonneted bat faces
significant risks from coastal squeeze, which occurs when habitat is
pressed between rising sea levels and coastal development that prevents
landward movement (Scavia et al. 2002; FitzGerald et al. 2008; Defeo et
al. 2009; LeDee et al. 2010; Menon et al. 2010; Noss 2011). The group
contended that human responses to sea level rise (e.g., coastal
armoring and landward migration) (Defeo et al. 2009, pp. 6-8) also pose
significant risk to bat habitat, and projected human population growth
and development in Florida threaten urban roosting sites with coastal
squeeze, particularly in North Fort Myers, Naples, Homestead, and Coral
Gables/Miami (Zwick and Carr 2006).
One commenter, who did not express support or opposition to the
proposed listing action, suggested that habitat development continues
in the species' range and the Service should require that surveys be
conducted in the core range before construction in natural habitat is
undertaken.
Our Response: We agree that habitat loss, modification, and
fragmentation are serious threats. The loss of forested habitat is
particularly concerning due to the species' forest-dwelling habits. We
agree that the loss of individual roosts may have been understated in
the proposed rule and have clarified the text accordingly (see also
Comment 6 and our response, above). We also acknowledge that we need to
work with partners to more fully understand the species' range for more
meaningful conservation.
Large-scale habitat losses in the core of the species' range are
particularly concerning. Land use changes at smaller scales may also
have individual or cumulative adverse impacts to the species. With this
final rule, the Federal protections provided by the Act for this
species (see Available Conservation Measures, below) are implemented.
This includes evaluation of the impacts of activities and consultation
under section 7 of the Act, prohibition of unauthorized take under
section 9 of the Act, and allowances for incidental take with habitat
conservation plans through the section 10 process. With this final
listing, proposed actions will be thoroughly evaluated through the
section 7 or section 10 process. With regard to the Eastern Collier
Multispecies HCP, as of July 2013, the applicants have submitted
incidental take permit applications, but remain in the process of
developing a draft HCP. The Service has awarded grant funding through
its Cooperative Endangered Species Conservation Fund to assist in the
development of the HCP. This proposed project, like others within the
species' current range, will be evaluated through the regulatory
framework provided by the Act.
We agree that coastal squeeze is a major problem, which will
accelerate in the future. We have revised the text to more fully
describe anticipated impacts (see Summary of Factors Affecting the
Species, Factor A, Alternative Future Landscape Models and Coastal
Squeeze, below, and Comments 8, 11, 16, and 20, and our responses to
them, below).
We agree that surveys for the species should be conducted prior to
large-scale land use changes within key natural habitats (e.g., forests
or water bodies) within the core range. We intend on working on an
acoustical survey protocol and broader survey guidelines, as indicated
above (see Comments 3 and 4, and our responses to them, above).
However, due to the difficulties in detection of this species, repeated
acoustical surveys for long periods of time may be needed. Acoustical
surveys, in combination with visual and other inspection of potential
roosting locations, may be helpful to avoid or minimize some impacts to
suspected roost sites. In some cases, bat activity and potential roosts
can be recognized (e.g., observation at emergence, vocalizations (roost
chatter), presence of ``ammonia''-like smell or guano). In cases where
acoustical surveys and other methods are not feasible, applicants and
agencies may need to assume presence prior to assessing impacts for
proposed projects and incorporate safeguards into their project
designs.
(8) Comment: With regard to foraging habitat and climate change,
one reviewer indicated that our assessment understated the negative
impact of climate change on prey availability. She indicated that plant
water stress would impact vegetation community structure, which would
likely affect insect availability for foraging bats. She also stated
that plant water stress would also affect the actual chemical
composition of plants, which also would impact the phenology of
phytophagous insects (i.e., those that feed on plants) and therefore
the timing of insect availability to foraging bats. She provided a
reference showing responses by plants and insects from experimentally
induced water deficits (Huberty and Denno 2004) and another that showed
that climate change is affecting the timing of seasonal flowering in
Florida (Von Holle et al. 2010). The reviewer stated that climate
[[Page 61020]]
change will alter prey availability to foraging bats.
Our Response: With regard to water deficits caused by climate
change, we acknowledge that we did not specifically evaluate the
responses by plants and potential impacts to insects and ramifications
to foraging bats in any detail. However, we briefly discussed the
species' susceptibility to changes in prey availability and possible
changes from climate change (see Summary of Factors Affecting the
Species, Factor E, Aspects of the Species' Life History and Climate
Change Implications, below). Since the reviewer's comments relate to
changes to foraging habitat, we have expanded the section (see Summary
of Factors Affecting the Species, Factor A, Climate Change and Sea
Level Rise, below) to more fully evaluate this threat. The potential
negative impact of climate change on prey availability is now more
fully described in this final rule. Additional comments relating to
climate change are provided below (see Comments 11 and 16, and our
responses to them, below).
(9) Comment: One reviewer indicated that the Florida bonneted bat
faces competition for tree cavities from native birds and mammals
(Belwood 1992, p. 220) and now dozens of introduced species, which also
use cavities (e.g., European starlings (Sturnus vulgaris), various
parrot species, black rats (Rattus rattus), and Africanized honey bees
(Apis mellifera scutellata)). He also suggested that the Florida
bonneted bat populations may also be impacted by the decline of red-
cockaded woodpeckers, which create cavities in living longleaf pine
trees.
One commenter suggested that the species' roosting habits were
``more precarious'' than its small range. He noted the limited supply
of woodpecker nest cavities and indicated that invasive species have a
significant impact on the Florida bonneted bat by competing for limited
roosting locations. In his view, introduced parrots are serious
competitors for natural and manmade cavities, as most of the more than
30 species of parrots and 2 to 3 species of mynahs observed in the wild
in south Florida use cavities. He indicated that Africanized honey bee
hybrids, established in Florida in 2005, are having significant impacts
on cavity-nesting wildlife throughout their expanding range (in Central
America, South America, the Caribbean, and southeastern United States).
He stated that Africanized honey bee hybrids occupy the entire range of
the Florida bonneted bat. The commenter suggested that research to
develop methods of reducing honey bee competition for cavities with
barn owls and parrots was underway, and that techniques may be
transferable to Florida bonneted bat roosting structures.
Our Response: We agree that tree cavities in south Florida are
likely limited and that competition for natural or artificial roosting
structures may be greater now than previously, due to a variety of
factors. Introduced species are becoming more abundant and widespread
in Florida, and some are likely contributing to increased competition
for a limited amount of suitable cavities or other roost sites. We have
added a new section entitled Competition for Tree Cavities (see Summary
of Factors Affecting the Species, Factor E, below).
We do not have information to support or refute the view that the
decline of red-cockaded woodpeckers (or other woodpeckers) may be
affecting Florida bonneted bat populations. One colony of Florida
bonneted bats was discovered in a longleaf pine tree cavity that had
been excavated by a red-cockaded woodpecker and later enlarged by a
pileated woodpecker (Belwood 1981, p. 412). In general, insufficient
numbers of cavities and continuing net loss of cavity trees are also
identified threats to the red-cockaded woodpecker (Service 2006, p. 7).
To help conserve the Florida bonneted bat, efforts should be made
to retain large cavity trees and snags wherever possible to reduce
competition for suitable roosts within the species' known range. The
use of artificial structures for the Florida bonneted bat may also be
beneficial in some locations. More research on the role of bat houses
in Florida bonneted bat conservation is needed (FWC 2013, pp. 10, 15).
The FWC plans on working with stakeholders to develop and implement
guidelines for building, installing, and monitoring bat houses for
Florida bonneted bats (FWC 2013, pp. 10-11).
(10) Comment: One reviewer noted that since the species may use
palm fronds for roosting, the trimming of palm fronds and removal of
mature palms for landscaping purposes may cause negative impacts. In
her view, these activities should be considered as potential threats.
Our Response: We agree and have clarified the text accordingly (see
Summary of Factors Affecting the Species, Factor E, Inadvertent and
Purposeful Impacts from Humans, below).
(11) Comment: Three reviewers and four commenters indicated that
hurricanes, storms, or other stochastic events are threats to the
species and its habitat. One reviewer emphasized the threat of
hurricanes as direct killing of bats and impacts to larger hollow trees
and bat houses. He noted the intensity and increasing damage of
tropical storms and contended that one large, intense storm (similar to
Hurricane Sandy in the northeast) could kill most of the Florida
bonneted bats over a broad area.
Another reviewer indicated that hurricanes may become more frequent
and intense with climate change. She suggested that the species may
occupy large snags with cavities, and that these trees and artificial
structures are likely to be damaged or destroyed during serious storm
events. She recommended that bat house structures be reinforced and
duplicated to prevent loss.
One group cited additional studies that show that the frequency of
high-severity hurricanes is increasing in the Atlantic (Elsner et al.
2008; Bender et al. 2010; Kishtawal et al. 2012), along with an
increased frequency of hurricane-generated large surge events (Grinsted
et al. 2012) and wave heights (Komar and Allan 2008). The group
contended that high winds, waves, and storm surge can cause significant
damage to the species' coastal habitat, noting that when storm surges
coincide with high tides, the chances for damage are greatly increased
(Cayan et al. 2008). Examples and additional references regarding sea
level rise, storm surge, and flooding were also provided. This group
stated that the Service must take into account the added impacts from
more severe hurricanes and increasing storm surge and coastal flooding
on the species' habitat. Another commenter also noted that severe
hurricanes can cause wetland degradation.
One commenter indicated that the limited supply of woodpecker nest
cavities has been compounded by the loss of snags due to hurricanes
(e.g., Hurricane Andrew 1994, hurricanes of 2004 and 2005). He added
there has also been a ``secondary hurricane effect with significant
changes to the South Florida Building Codes post Hurricane Andrew that
reduces roosting locations under tile roofs.''
Our Response: We agree that the species and its habitat appear
highly vulnerable to hurricanes and storms. Intense events could kill
or injure individual bats and destroy limited roosting habitat (see
Summary of Factors Affecting the Species, Factor E, Environmental
Stochasticity, below). Even one event can have devastating impacts due
to the species' restricted range. Increased frequency and intensity of
hurricanes, storm surges, and
[[Page 61021]]
flooding events are also expected with climate change. We have revised
portions of our assessment accordingly (see Summary of Factors
Affecting the Species, Factors A and E below). See also detailed
comments on climate change in Comment 16 and our response, below.
We believe that natural roost sites are limiting and that the use
of artificial structures can play an important role in conserving the
species. We concur with the suggestion that bat houses be reinforced
and duplicated to prevent loss.
We do not dispute the claim that changes to the South Florida
Building Codes after Hurricane Andrew reduced potential roosting
locations under tile roofs. However, it is not known the extent to
which the species uses such structures. It is possible that changes in
building codes affected roosting opportunities in residential and urban
areas.
(12) Comment: Two reviewers and the FWC remarked on predation as a
threat to the species. One reviewer suggested that the loss of bats to
snake predation is under appreciated, especially with the increasing
numbers of introduced snakes, and recommended that additional measures
be taken to protect bats and other native species. He also emphasized
the fragile nature of the Florida bonneted bat populations, noting that
although some are located on protected lands, these populations are
still quite exposed to severe threats. Another reviewer noted that the
species presumably experiences some level of predation from native
wildlife (e.g., hawks, owls, raccoons, rat snakes), but that introduced
reptiles (e.g., young Burmese pythons (Python molurus bivittatus) and
boa constrictors (Boa constrictor)) may also have or will have an
impact on the Florida bonneted bat population.
The FWC questioned our conclusion that predation is not impacting
the species and offered that a more conservative approach is that too
little information exists to draw any conclusions about the impacts of
predation.
Our Response: We generally agree with the comments we received
regarding predation and have adjusted the text accordingly (see Summary
of Factors Affecting the Species, Factor C. Disease or Predation,
below).
(13) Comment: One reviewer commented on white-nose syndrome (WNS)
and noted that very little is known about the fungus, Geomyces
destructans, and the disease. She suggested that the Florida bonneted
bat may not be impacted by the disease, since it does not hibernate and
the disease has only impacted hibernating species to date. However, she
also cautioned that since the fungus is new to science and North
America, how it may evolve and change is unknown. She urged that the
Service be cautious and not assume that impacts will not occur in the
future.
Our Response: We agree and have updated the text of this final rule
accordingly.
(14) Comment: One reviewer stated that although the death of bats
at wind energy facilities is fairly well documented, the numbers of
bats killed is still considerably underappreciated. He stated that bats
die in considerable numbers at wind turbines, and with the current push
to develop greener energy sources, the loss of bats at wind turbines
will increase.
Our Response: We acknowledge that the number of bats killed at wind
energy facilities is not known, and that the extent of mortality, in
some locations, may not be fully understood. Although increases in the
number of wind energy facilities are likely to cause increases in bat
mortality, numerous factors are involved (see Summary of Factors
Affecting the Species, Factor E, Proposed Wind Energy Facilities,
below). In some cases, impacts may be avoided and minimized. Available
guidelines, if implemented, can help reduce bird and bat mortalities.
We agree that this threat is likely to increase as demand increases,
and we revised the text of this final rule accordingly.
(15) Comment: One reviewer stated that ``the lack of regulatory
mechanisms particularly when in contact with humans'' was among the
most important potential threats to the species, emphasizing that
public education about bats is crucial.
The Florida Department of Agriculture and Consumer Services
(FDACS), expressing neither support of nor opposition to the proposed
listing, indicated that there may be opportunity to provide education
and outreach to professional wildlife trappers and pest control
operators ``to limit take of this imperiled species.'' FDACS offered to
develop, with the help of FWC and the Service, an informational
bulletin, which could be distributed to pest control operators either
during training for certification or renewal. Additionally, information
relating to the bat, including identification, could be incorporated as
a component of training and exams for limited certification for
commensal rodent control. The FDACS also expressed willingness to meet
with the FWC and the Service to discuss training and outreach
opportunities to educate wildlife trappers, law enforcement, county
health departments, and local animal control on rules and regulations
that are required to protect the Florida bonneted bat and other bat
species.
One commenter, in opposition to the proposed listing, suggested
that development of educational programs and materials may be the most
important conservation measure, citing Robson (1989). The same
commenter recommended that the species not be listed and instead
suggested that public education on the value and importance of bats be
stressed. This commenter specifically recommended further education on
appropriate bat house designs and the use of environmentally friendly
lighting practices.
Our Response: We believe that regulatory (see Summary of Factors
Affecting the Species, Factor D, below) and other mechanisms to deal
with bat and human interactions can be improved. We agree that
education for the public and various groups is imperative, and that
this should be an integral part of conservation efforts for the Florida
bonneted bat. We appreciate both suggestions from the FDACS on ways to
reduce the taking of this species during wildlife removal and pest
control operations and their willingness to help raise awareness,
improve training, and expand education. We look forward to working with
partners on this.
While expanded education and outreach programs are important
components of conservation, the species meets the definition of an
endangered species and faces numerous significant threats (see
Determination of Status, below), many of which could not be alleviated
through education alone. We are hopeful that improved awareness and
education, along with the protections afforded to the species and
habitat (see Available Conservation Measures, below), will allow the
species to continue to persist and recover. See also Comment 32 and our
response, below.
(16) Comment: With regard to climate change, two reviewers provided
specific comments. One reviewer felt that climate change has the
potential to negatively impact the species, especially in the context
of impacts from altered storm frequency and intensity. Another reviewer
appeared to generally agree with our assessment of anticipated impacts
from climate change, but indicated that the negative impact of climate
change on prey availability had been understated.
One group provided extensive comments and references. The group's
main points included the following: (a)
[[Page 61022]]
Global sea-level rise is accelerating in pace and is likely to increase
by one to two meters within the century; (b) sea-level rise of 1 to 2
meters in south Florida is highly likely within this century; (c)
storms and storm surges are increasing in intensity; (d) coastal
squeeze threatens the species' habitat; (e) climate change threats
should be analyzed through the year 2100 at minimum; and (f) sea-level
rise will have significant impacts on Florida bonneted bat roost sites.
More specifically, the group asserted that the Service analyze the
impacts of sea-level rise of up to 2 meters on the Florida bonneted
bat's habitat since this falls within the range of likely scenarios and
since sea-level rise will be exacerbated by increasing storm surge.
With regard to roost sites, the group estimated impacts to roost site
locations from climate change, based upon the colony numbers and
locations provided in the proposed rule and using NOAA's sea level rise
and coastal flooding impacts viewer. Based upon this tool, the group
suggested that 9 of 11 roost locations would either be fully or partly
inundated with sea-level rises ranging from 30 centimeters (11.8
inches) to 1.8 m (5.9 ft). This analysis highlights the ``extreme
vulnerability'' of bonneted bat roosting habitat to sea-level rise.
The group also provided additional comments with regard to critical
habitat and climate change.
Our Response: With regard to climate change, we agree with the
general comments provided. The additional literature on climate change
provided by one group largely reinforces our assessment of the threat
of climate change to the Florida bonneted bat and its habitat. We
appreciate the references provided and have revised our assessment
accordingly.
With regard to specific comments, we agree with the view that sea-
level rise is likely to have significant impacts on Florida bonneted
bat roosts. However, the locations of natural roost sites and colony
locations are not known (see also Comment 21 and our response, and
Summary of Changes from Proposed Rule, below). Given the limited
available information, it is not possible to quantify the number of
roosting locations that will be impacted by sea-level rise. Still, we
anticipate significant losses of occupied and potential occupied
habitat in coastal areas due to climate change (see Summary of Factors
Affecting the Species, Factor A, Climate Change and Sea Level Rise and
Alternative Future Landscape Models and Coastal Squeeze, and Factor E,
Aspects of the Species' Life History and Climate Change Implications,
below). Portions of the species' roosting habitat are vulnerable to
sea-level rise, and impacts to foraging habitat may also occur with
climate change (see also Comment 8 and our response, above).
Detailed comments related to storms and storm surges are provided
and addressed above (see Comment 11 and our response, above). Detailed
comments related to coastal squeeze are provided and addressed above
(see Comment 7 and our response, above). We have revised portions of
our assessment accordingly (see Summary of Factors Affecting the
Species, Factors A and E, below).
Comments regarding climate change in relation to critical habitat
are provided below (see Comment 20 and our response, below).
(17) Comment: One reviewer stated that the species was not a widely
distributed species prior to development in southern Florida in the
past century, but the ``increased and indiscriminate use of pesticides
in the 1950s-1960s no doubt started the species in decline.'' Other
commenters offered alternate and more detailed views about pesticides.
Our Response: We agree that the species appears to not have been
widely distributed during the past century, based upon available
information. However, we have no evidence indicating that the use of
pesticides led to the species' decline (see Comments Relating to
Pesticides, below).
(18) Comment: One reviewer explicitly stated that listing the
Florida bonneted bat as an endangered species will provide several
benefits that will aid in the protection and possible recovery of the
species. He pointed to conservation actions taken at Florida Caverns
State Park in the 1990s for the endangered gray bat (Myotis
grisescens), which would not have been implemented had it not been for
Service funding made available through the Act.
Our Response: We agree that listing provides many benefits for
species and their habitats (see Available Conservation Measures,
below).
Comments Relating to Critical Habitat
(19) Comment: With regard to timing, three peer reviewers agreed
with our finding that critical habitat was not determinable due to lack
of knowledge or the need for more information. One reviewer stated that
a study that identifies home ranges and habitat affinities is
imperative to determining the physical and biological features
essential to the conservation of the species. In her view, designation
of critical habitat is appropriate, but for it to be meaningful and
effective, the extent of the species' range and the species' roosting
affinities should be defined prior to designation. She indicated that
if that was not possible, then additional future information that
informs habitat use should be used to modify any critical habitat
designation.
Two commenters, both representing environmental groups, indicated
that critical habitat designation should be a timely goal or completed
promptly. One group specifically stated that the Service should seek
the scientific information necessary to propose critical habitat
promptly, and that until critical habitat can be identified and
designated, the Eastern Collier Multispecies HCP should not move
forward.
Another group reminded the Service of its responsibilities under
the Act, stating that a ``not determinable'' finding allows the Service
to extend the time for designating critical habitat. Under the Act, the
Service has 2 years from the date of the proposed listing decision (or,
in this case, 1 year from the date of the final listing decision) to
designate critical habitat. The group cited case law and stated that
the deadlines apply even if longer deliberation would produce a
``better'' critical habitat designation. In this view, ``not
determinable'' findings should rarely be made, and the Service should
make ``the strongest attempt possible'' to determine critical habitat.
The group further stated that the Service is to use the best available
science, and that ``optimal conditions'' are unknown is not a barrier
to designating critical habitat. The group stated that it is not the
Service's task to understand what features of occupied habitat are
lacking, but to synthesize information about what is known about the
species and its habitat needs.
Our Response: The Service continues to work with researchers, other
agencies, and stakeholders on filling large information gaps regarding
the species and its habitat needs and preferences. We intend to publish
a proposed critical habitat designation for the Florida bonneted bat in
a separate rule within our statutory timeframe and have continued to
fund research and study the habitat requirements of the bat.
With this final listing determination, the species will now receive
regulatory consideration under sections 7 and 10 of the Act and will
benefit from other protections (see Available Conservation Measures,
below). Potential impacts from proposed projects within the species'
current range will be evaluated under these regulatory frameworks.
(20) Comment: One peer reviewer stated that properties occupied by
extant and active colonies are clearly
[[Page 61023]]
essential to the conservation of the species. She suggested that the
roost and surrounding habitats in both Lee County and at Babcock-Webb
WMA provide elements essential to the conservation of the colonies and
should be designated as such. She recommended that conservation
easements for the private property in Lee County be pursued and that
conservation of Florida bonneted bats and their roosts be prioritized
in the long-term management of Babcock-Webb WMA.
One group requested that the proposed critical habitat designation
account for seasonal shifts in roosting sites. In addition, the group
requested that the Service consider, ``specific areas outside the
geographical area occupied by the species at the time it is listed,
upon a determination that such areas are essential for the conservation
of the species.''
Another group provided extensive comments relating to how a
critical habitat designation must buffer the species from climate
change threats. This group provided new literature related to climate
change and contended that coastal Florida is particularly vulnerable to
habitat losses caused by climate change (e.g., Cameron Devitt et al.
2012). It argued that unoccupied inland habitat area that can provide
roosting and foraging habitat should be identified and designated as
critical habitat for the species. It also contended that as species and
habitats shift in response to climate change, it will be important to
protect habitat areas outside of the current range, including
``stepping stone patches'' and corridors. In the group's estimation, 9
of 11 roosting locations are highly vulnerable to inundation by sea-
level rise; therefore, proactive protection of suitable inland areas
for future roosting and foraging habitat is necessary. The group also
provided examples of the Service's designation of unoccupied habitat as
critical habitat to buffer six species from climate change impacts. It
stated that there was ``ample precedent, legal authority, and
conservation imperative'' for the Service to similarly identify and
designate unoccupied inland habitat for the Florida bonneted bat to
buffer it from the effects of sea level-rise and increasing storm
surge.
Our Response: The Service will fully consider these comments and
all available information during the process of identifying areas
essential to the conservation of the species and in its proposal to
designate critical habitat.
Comments From the State
Section 4(i) of the Act states, ``the Secretary shall submit to the
State agency a written justification for his failure to adopt
regulations consistent with the agency's comments or petition.''
Comments we received from the State of Florida are addressed below.
(21) Comment: The FWC provided additional information regarding a
new roost documented at Babcock-Webb WMA, suggested alternatives for
characterizing roosting sites and colonies, offered clarifications
relating to threats, and suggested other minor clarifications and
corrections.
With regard to colonies, the FWC suggested a more conservative
approach may be to identify an area as occupied, without attempting to
estimate the number of colonies. The FWC noted that much of the
information for estimation of colony size, number of colonies, and
locations was based on acoustical data and inferences, and that since
so little is known about roosting and foraging ecology, it is difficult
to correlate bat calls to colonies. In this view, even at sites with
roosts identified (e.g., Babcock-Webb WMA), determining the number of
colonies present is difficult because of the composition of colonies
(e.g., harem, maternity, bachelor, and potential seasonal changes) is
not well understood, and the movement between roost sites by a colony
has not been studied.
The FWC also confirmed that it is currently developing a management
plan that is similar in scope to a Federal recovery plan and stated
that the objectives of the State plan will be to reverse threats
causing the decline of the species. The FWC expressed desire to
continue coordination with the Service in the development of both the
State management plan and the Federal recovery plan.
Our Response: We have incorporated the new information and have
clarified portions of the text accordingly. We agree that it is better
to identify areas as occupied rather than attempting to estimate the
number of colonies and their locations. Therefore, we have
substantially revised our discussion of colonies, replacing it with a
more general discussion (see Background, above) based upon comments
from the FWC, peer reviewers, and other commenters. See also Comment 6
and our response, above, and Summary of Factors Affecting the Species,
Factors C, D, and E, below.
We intend to draw upon the State's management plan and all other
relevant sources during recovery planning and implementation efforts.
We will be soliciting input from the State and other stakeholders, who
are integral in the conservation of the species, during recovery
planning.
(22) Comment: The FDACS stated that the protective provisions under
Florida Administrative Code (F.A.C.) chapter 68A-27 and chapter 68A-
9.010 are important for the Florida bonneted bat since professional
wildlife trappers and pesticide control operators may not be able to
identify the species of bat they are attempting to exclude and may not
be aware of the take prohibitions for listed species. The FDACS also
indicated that the State's Structural Pest Control Act (Florida
Statutes, chapter 482) does consider bats to be pests under certain
situations and includes bats in the definition of ``rodent,'' even
though bats are in the order Chiroptera. Despite the definition,
however, the FDACS does not regulate commercial trapping or removal of
bats, as they are protected under F.A.C. chapter 68A-9.010. The FDACS
does regulate control of ``commensal rodents'' (i.e., rats and mice) in
or near structures and the use of pesticides, including pesticides to
control nuisance wildlife (i.e., poisons and repellants).
The FDACS also stated that limited certification does not authorize
the use of any ``pesticide or chemical substances, other than adhesive
materials, to control rodents or other nuisance wildlife in, on, or
under structures.'' For bats, only exclusion devices or registered
chemical repellents can be used as specified under F.A.C. chapter 68A-
9.010. Currently, only naphthalene (e.g., Bat-A-Way) is registered as a
bat repellent in Florida. Since this product is a pesticide, a
professional applicator would need to possess a full pest control
operator's license.
The FDACS stated that all bat species in Florida are protected
under F.A.C. chapter 68A-9.010, but unlisted bats can be taken
(federally listed or State-listed species require an incidental take
permit) if located within a structure through the use of an exclusion
device or a registered repellant if used from August 15 to April 15.
The use of a repellent by professional pest control or wildlife
management personnel to remove bats from within a structure requires a
pest control operator's license. The use of poisons on bats is not
permitted.
Our Response: We appreciate the clarifications provided and have
adjusted the text accordingly (see Summary of Factors Affecting the
Species, Factor D, below). We maintain that existing regulatory
measures, due to a variety of constraints, do not provide adequate
protection (see Factor D). The species also remains at risk due to the
effects of a wide array of threats (see
[[Page 61024]]
Summary of Factors Affecting the Species, Factors A and E, below).
Comments Relating to Pesticides
(23) Comment: The FDACS explained the role that it assumes during
the registration and regulation of pesticide products in Florida under
the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). The
FDACS also confirmed that organophosphate (OP) pesticides are highly
toxic to mammals and that pyrethroids are generally of low toxicity to
mammals. It also noted the marked decrease in OP pesticides in
residential and urban areas in recent years and replacement with
synthetic pyrethroids, which are much less toxic to birds and mammals.
Naled, an OP pesticide, has reportedly been used for decades for
both mosquito control and agriculture, but no incidents concerning
direct impacts to bats have been reported to the U.S. Environmental
Protection Agency (EPA) (EPA 2008). In this view, it is possible that
Florida bonneted bats are exposed to OP insecticides used in
agriculture, but their habits of flying at heights of 9 m (30 ft) or
more would likely minimize exposure to OP pesticide residues, which
tend to kill insects quickly at crop level. The FDACS also indicated
that it is not aware of data that document significant reductions in
larger insect species (coleopterans, dipterans, and hemipterans) that
are primarily consumed by bats in areas that receive mosquito control.
The FDACS also noted that without scientific evidence, claims that
mosquito control has reduced the Florida bonneted bat's food supply
should be considered anecdotal.
Two commenters contended that listing of the Florida bonneted bat
may limit mosquito control activities, leading to an increase in the
public's risk of exposure to West Nile virus, dengue fever, Saint Louis
encephalitis, eastern equine encephalitis, and other diseases
transmitted by mosquitoes. Concerns that quality of life for residents
and visitors would be reduced, tourism would be hindered, and the
economy would suffer if mosquito control operations were limited were
also expressed. The commenters also noted that a location in North Fort
Myers that regularly receives aerial mosquito control application has
continued to support a Florida bonneted bat population, which has
increased in recent years. It was also stated that the species' densest
populations occur where mosquito control has existed for 30 years. Both
commenters stated that the proposed rule suggested that mosquito
control activities have either impacted the bat directly or reduced
insect populations that serve as the food source for the Florida
bonneted bat without providing scientific evidence in support of such
claims. One commenter suggested that the entire Pesticides and
Contaminants section be removed from the text, and if not removed,
revised to indicate that mosquito control pesticides are not a threat.
Our Response: We appreciate the explanations provided by FDACS and
have made adjustments to the text, where applicable. We agree with the
commenters' assertion that no direct scientific evidence exists that
links mosquito control activities (or pesticides) with impacts to the
Florida bonneted bat, either directly or through a reduction in prey
base. Although dietary studies are underway, information on the
species' prey base and prey availability are generally lacking. Studies
to assess the availability of prey in portions of the species' range
using various methods (e.g., emergence traps, radar and remote sensing)
could help better assess habitat needs and potential threats.
We do not agree with the assertion that mosquito control activities
are implicated as having an adverse impact on the Florida bonneted bat.
Impacts from mosquito control activities are not the basis for the
listing of the Florida bonneted bat. The suggestions by the commenters
that mosquito control operations would cease or be severely limited,
and thus impact tourism and the economy, if the Florida bonneted bat is
listed are not accurate. Such actions have not been recommended by the
Service.
We do not have evidence to substantiate the commenters'
characterizations of Florida bonneted bat population increases in the
North Fort Myers area or that the densest populations of Florida
bonneted bats occur in areas that have been treated with mosquito
control pesticides for 30 years. In fact, the size of the colony in
North Fort Myers has remained relatively constant since 2008, except
for the mortality observed after a prolonged cold event in 2010 (S.
Trokey, pers. comm. 2008a-b; 2010a-c; 2011, 2012a, 2013). We have no
information on population density for any areas.
Content in the Pesticides and Contaminants section (see Summary of
Factors Affecting the Species, Factor E, below) is meant to be an
assessment of the current state of knowledge regarding contaminant
impacts to the Florida bonneted bat. Such an assessment involves
characterizing an organism's known or potential field exposure to
contaminants, as well as characterizing the biological effects related
to such exposure scenarios. While assessing exposure, we maintain that
there is a possibility that the Florida bonneted bat may be exposed to
pesticides, including mosquito control chemicals. We also acknowledge
that such exposures, while possible, have not been quantified. A risk
estimate presented in the Interim Reregistration Eligibility Decision
for Naled (EPA 2002, pp. 36, 38) indicates that a conservative
endangered species level of concern is exceeded for insectivorous
mammals when considering mosquito control usages. While this
conservative estimate does not indicate imminent adverse impacts, it
does suggest that potential mosquito control impacts should be
evaluated. We plan to conduct limited analysis as a first step toward
understanding possible pathways of exposure and hope to expand studies,
if possible.
The same type of assessment was conducted for invertebrates that
the Florida bonneted bat may prey upon. We maintain that it is possible
that non-target invertebrates, some of which may be prey for the
Florida bonneted bat, are exposed to mosquito control chemicals. We
also acknowledge that such an exposure, while possible, has not been
quantified. Without quantifiable exposure scenarios, environmentally
relevant biological effects on the Florida bonneted bat or its prey
base cannot be attributed to mosquito control activities. The fact that
quantifiable exposure and effects data are not available does not
preclude an examination of potential impacts and an acknowledgement of
what is known and unknown. We have clarified this section accordingly
(see Summary of Factors Affecting the Species, Factor E, Pesticides and
Contaminants, below).
(24) Comment: The FDACS indicated that in an agricultural setting
OP pesticides are expected to quickly kill insects at crop level, well
below the expected foraging height of the Florida bonneted bat.
Another commenter stated that insecticides used against flying
insects quickly impair their nervous systems and render them unable to
fly, thus avoiding a scenario where pesticide-laden flying insects
would be consumed by the Florida bonneted bat. The commenter stated
that most of the spray cloud of mosquito adulticide following truck
application remains below 10 m (33 ft), which is lower than the Florida
bonneted bat is expected to forage. It was also stated that mosquitoes
are small-bodied insects that make up less than 1 percent of a bat's
diet and that higher application rates than what are
[[Page 61025]]
currently used would be needed to kill larger bodied insects.
Similarly, another commenter stated that for the Florida bonneted bat
to use mosquitos as a food source would be highly inefficient
energetically.
Our Response: We agree that mosquitoes and other small-bodied
insects are not likely to be consumed by the Florida bonneted bat,
which is thought to prey upon larger insects (see Background, Life
History, above). Small-bodied insects that have been exposed to
mosquito control chemicals or agricultural pesticides through ground
applications may also die quickly near ground level, as one commenter
purports. The likelihood of larger-bodied insects that are exposed to
sublethal concentrations of pesticides being consumed by the Florida
bonneted bat remains unknown, but warrants further investigation.
Although foraging likely occurs either at high altitudes or in fairly
open habitat (H. Ober, in litt. 2012), the Florida bonneted bat may
also prey upon ground insect species because it can take flight from
the ground like other Eumops spp. (Ridgley 2012, pp. 1-2). Dietary
preferences and foraging behavior remain poorly understood. The Service
is working with researchers and partners to fill information gaps to
better understand and conserve the species and its habitat.
(25) Comment: The FDACS suggested that characterizing pesticide
exposure should be given lower priority than obtaining more information
regarding the basic life history of the Florida bonneted bat. It also
suggested that future considerations for researching the potential
impacts of mosquito control practices on the Florida bonneted bat
should be discussed at a meeting of the Florida Coordinating Council
for Mosquito Control's Subcommittee for Imperiled Species.
Our Response: We believe that obtaining additional information on
the species' life history should be a high priority. We agree that the
aforementioned subcommittee is a good venue to discuss pesticide risk
and exposure with other agencies and mosquito control personnel. We
look forward to working with researchers and partners on better
understanding and reducing threats to the species.
Federal Agency Comments
(26) Comment: The NPS (ENP) provided additional data from 39
acoustical surveys in and around ENP from June 2012 to November 2012;
the species was detected during 4 surveys. ENP also provided results
from searches for ``feeding buzzes'' and queried biologists to gain
insight into foraging habitat. A correction was suggested for Table 1.
Our Response: We have incorporated the new data and information and
have clarified portions of the table and text accordingly. See also
Comment 5 and our response, above.
Public Comments
(27) Comment: One commenter indicated that the Florida bonneted bat
may be found in the following counties: Charlotte, Lee, Collier,
Monroe, Miami-Dade, Okeechobee, Polk, and Glades.
Our Response: We agree that the Florida bonneted bat occurs in most
of the aforementioned counties. Available data indicate presence of the
Florida bonneted bat in portions of Charlotte, Lee, Collier, Monroe,
Miami-Dade, Okeechobee, and Polk Counties (see Table 1 and Occupied and
Potential Occupied Areas, above). Range maps also include fractions of
Glades, Hendry, and Broward Counties (Marks and Marks 2008a, p. 11;
2012, p. 11); however, current presence in these counties is uncertain.
(28) Comment: One commenter requested clarification to the place
referred to as ``Snapper Creek Park'' in Table 1, indicating that it is
not known by that name, adding that Snapper Creek is a water management
canal that is lined by a number of small parks and also linear
bikeways.
The commenter also provided additional information for the area
surrounding the Zoo Miami, known as Richmond Pinelands. This commenter
stated that the 10-km\2\ (4- mi\2\) area contains 344 hectares (ha)
(850 ac) of pine rockland forest and that Miami-Dade Parks manages 223
ha (550 ac). It was also noted that the Federal Government and
University of Miami hold large parcels in this area. In this view,
undeveloped open spaces owned by Miami-Dade County, the Federal
Government, and the University of Miami likely provide habitat for the
Florida bonneted bat.
Our Response: We have verified that ``Snapper Creek Park'' is the
correct name for the place where the Florida bonneted bat was recorded.
It is a small park located near a canal; signage indicates that the
property is owned by Miami-Dade County (C. Marks, pers. comm. 2013). We
agree that the Richmond Pinelands area may also provide habitat for the
species and have clarified portions of the text of this final rule.
(29) Comment: Seven commenters stated that bats are crucial parts
of ecosystems, providing benefits such as consuming insects, reducing
the need to use pesticides, dispersing seeds, and pollinating plants.
Another commenter provided a reference (Kunz et al. 2011, pp. 1-38),
which discusses the ecosystem services provided by bats.
Our Response: We agree and acknowledge that bats are vital
components of ecosystems and provide enormous benefits. However, the
role of bats in the ecosystem and their contributions are beyond the
purpose of our assessment and not part of our determination.
(30) Comment: One commenter in opposition to the proposed listing
argued that survey information was inadequate and actual forage sites
have not been scientifically determined. In this view, the use of this
type of information to indicate level of threat to the species'
foraging habitat is not valid.
Our Response: Although we agree that foraging habitat is not fully
known, we disagree that our assessment is not valid. As directed by the
Act, we have used the best available scientific information to identify
and assess threats to the Florida bonneted bat and make our listing
determination. Uncertainties are also explained for individual threats
(see Summary of Factors Affecting the Species, below). More information
on the species, its habitat, and threats will undoubtedly improve
understanding and enhance conservation efforts in the future.
(31) Comment: One commenter questioned our use of unpublished data
from a 1982 survey of pest control operators showing a dramatic
decrease in requests for nuisance bat removal beginning in the 1960s as
being indicative of reduced bat abundance. The commenter stated that
this only indicated that fewer people had bats in their buildings,
which may be attributed to a change in building techniques to conserve
energy and provide better bat exclusion. In this view, this survey
cannot be used to justify listing the Florida bonneted bat.
Our Response: We do not have information to support or refute the
commenter's claim as to the cause for the decrease in requests for bat
removal. Taken alone, results of the survey (provided in Belwood (1992,
p. 217)) would not be enough to justify a listing action. However, we
assessed this information and all other available data and information
(see Background, above, and Summary of Factors Affecting the Species,
below) in making our determination (see Determination of Status,
below).
(32) Comment: One commenter in opposition to the proposed listing
suggested that artificial night lighting is affecting the prey base of
bats. The
[[Page 61026]]
commenter cited Rich and Longcore (2006) who stated that artificial
lighting is extremely detrimental to many insect populations and can
change the diversity of insects in some locations. It was also noted
that night lighting is widespread, is unregulated, and kills insects
every night. The commenter suggested that night lighting may be
contributing to the loss of habitat, noting that some bats use
streetlights as hunting opportunities, while others avoid the lights.
The commenter recommended that bat houses be placed away from night
lighting and that the use of environmentally friendly lighting
practices be promoted.
Our Response: We agree that artificial lighting can have negative
impacts on wildlife and may be affecting insect abundance and diversity
in some locations. How artificial lighting affects the Florida bonneted
bat's activities and prey base needs further investigation. We have
added a section to our threats analysis (see Summary of Factors
Affecting the Species, Factor E, Ecological Light Pollution, below).
Where lighting is necessary, we encourage the use of environmentally
friendly lighting practices to minimize impacts to wildlife.
Summary of Changes From Proposed Rule
We made changes to the final listing rule, after consideration of
the comments we received during the public comment period (see above)
and new information we received since publication of the proposed rule.
Many small, nonsubstantive changes and corrections, not affecting the
determination (e.g., updating the Background section in response to
comments, and to make minor clarifications) were made throughout the
document. The more substantial changes are:
(1) We revised our discussion of colonies, removed the section
entitled Estimating Colony Sizes and Locations, and added a more
general section entitled Occupied and Potential Occupied Areas (see
Background, above).
(2) We assessed the potential effects of artificial night lighting
in a new section entitled Ecological Light Pollution (see Summary of
Factors Affecting the Species, Factor E, below).
(3) We revised our assessment of climate change and more fully
included potential impacts to prey availability and foraging habitat
from climate change (see Summary of Factors Affecting the Species,
Factors A and E, below).
(4) We assessed the potential effects of competition for limited
roost sites in a new section entitled Competition for Tree Cavities
(see Summary of Factors Affecting the Species, Factor E, below).
(5) We revised our assessment of predation to more fully consider
the potential impacts from native wildlife and nonnative snakes (see
Summary of Factors Affecting the Species, Factor C, below).
(6) We incorporated data from new and ongoing studies (see
Background, above).
The new additions and modifications summarized above did not change
our determination.
Summary of Factors Affecting the Species
Section 4 of the Act (16 U.S.C. 1533), and its implementing
regulations at 50 CFR part 424, set forth the procedures for adding
species to the Federal Lists of Endangered and Threatened Wildlife and
Plants. Under section 4(a)(1) of the Act, we may list a species based
on any of the following five factors: (A) The present or threatened
destruction, modification, or curtailment of its habitat or range; (B)
overutilization for commercial, recreational, scientific, or
educational purposes; (C) disease or predation; (D) the inadequacy of
existing regulatory mechanisms; and (E) other natural or manmade
factors affecting its continued existence. Listing actions may be
warranted based on any of the above threat factors, singly or in
combination. Each of these factors is discussed below.
Factor A. The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
Habitat loss and alteration in forested and urban areas are major
threats to the Florida bonneted bat (Belwood 1992, p. 220; Timm and
Arroyo-Cabrales 2008, p. 1). In natural areas, this species may be
impacted when forests are converted to other uses or when old trees
with cavities are removed (Belwood 1992, p. 220; Timm and Arroyo-
Cabrales 2008, p. 1). In urban settings, this species may be impacted
when buildings with suitable roosts are demolished (Robson 1989, p. 15;
Timm and Arroyo-Cabrales 2008, p. 1) or when structures are modified to
exclude bats. Although the species' habitat preferences and extent of
range are not well understood, significant land use changes have
occurred in south Florida and additional habitat losses are expected in
the future, placing the species at risk. Uncertainty regarding the
species' specific habitat needs and requirements arguably contributes
to the degree of this threat. Without more information on roosting
sites and important foraging areas, inadvertent impacts to and losses
of habitat may be more likely to occur through various sources and
stressors (see below), and habitat losses will likely be more difficult
to avoid. Since the Florida bonneted bat is suspected to have high
roost site fidelity, the loss of a roost site may cause greater
hardship to the species than the loss of a roost site for other, more
labile species (H. Ober, in litt. 2012).
Land Use Changes and Human Population Growth
Significant land use changes have occurred through time in south
Florida, including major portions of the species' historical and
current range. In his examination of Florida's land use history,
Solecki (2001, p. 350) stated that tremendous land use changes took
place from the early 1950s to the early and mid-1970s. During this
time, ``an almost continuous strip of urban development became present
along the Atlantic coast'' and urban land uses became well established
in the extreme southeastern portion of the region, particularly around
the cities of Miami and Fort Lauderdale and along the entire coastline
northward to West Palm Beach (Solecki 2001, p. 350). Similarly, Solecki
(2001, p. 345) found tremendous urban expansion within the Gulf coast
region, particularly near Ft. Myers since the 1970s, with the rate of
urban land conversion superseding the rate of agricultural conversion
in recent decades.
In another examination, the extent of land use conversions for
southwest Florida (Collier, Lee, Hendry, Charlotte, and Glades
Counties) between 1986 and 1996 was estimated using a change detection
analysis performed by Beth Stys (FWC, unpublished data) (Service 2008,
p. 37). The area of disturbed lands increased 31 percent in these five
counties between 1986 and 1996, with the greatest increases in
disturbed lands occurring in Hendry and Glades Counties. Most (66
percent) of the land use change over the 10-year period was due to
conversion to agricultural uses. Forest cover types accounted for 42
percent of land use conversions, dry prairies accounted for 37 percent,
freshwater marsh accounted for 9 percent, and shrub and brush lands
accounted for 8 percent.
In another analysis, Stys calculated the extent of seminatural and
natural lands that were converted to agricultural and urban or
developed areas in Florida between 1985-1989 and 2003 (B. Stys, pers.
comm. 2005; Service 2008, p. 38). Based upon this analysis,
approximately
[[Page 61027]]
1,476 km\2\ (570 mi\2\) of natural and seminatural lands in Glades,
Hendry, Lee, Collier, Broward, Monroe, and Miami-Dade Counties were
converted during this time period (FWC, unpublished data). Of these,
approximately 880 km\2\ (340 mi\2\) were conversions to agricultural
uses and 596 km\2\ (230 mi\2\) to urban uses. In Charlotte County,
26,940 ac (10,902 ha) (9.6 percent of the county) were converted to
agriculture, and 21,712 ac (8,787 ha) (7.8 percent) were converted to
urban uses in the time period examined. In Lee County, 16,705 ac (6,760
ha) (6.3 percent) were converted to agriculture, and 44,734 ac (18,103
ha) (16.8 percent) were developed. In Collier County, 34,842 ac (14,100
ha) (3.1 percent) were converted to agriculture, and 38,331 ac (15,512
ha) (3.4 percent) were developed. Several large-scale developments,
mines, and transportation projects, totaling thousands of acres, are
being planned, have been reportedly proposed, or are pending in
portions of south and southwest Florida occupied by the species (A.
Crooks, in litt. 2012).
Habitat loss and human population growth in south Florida are
continuing. The human population in south Florida has increased from
fewer than 20,000 people in 1920, to more than 4.6 million by 1990
(Solecki 2001, p. 345). The population of Miami-Dade County, one area
where the Florida bonneted bat was historically common, increased from
fewer than 500,000 people in 1950, to nearly 2.6 million in 2012
(http://quickfacts.census.gov). In one projection, all counties with
current Florida bonneted bat occurrences were forecasted to increase in
human population density, with most counties expected to grow by more
than 750 people per square mile by 2060 (Wear and Greis 2011, pp. 26-
27).
In another model, three counties with current known occurrences of
the Florida bonneted bat--Charlotte, Lee, and Collier--are expected to
reach buildout (fully develop) before 2060 (Zwick and Carr 2006, pp.
12-13, 16). For the period between 2040 and 2060, the population of Lee
and Collier Counties is projected to exceed the available vacant land
area, so the population was modeled to allow spillover into adjacent
counties (Zwick and Carr 2006, p. 13). According to human population
distribution models, south Florida is expected to become mostly
urbanized, with the exception of some of the agricultural lands north
and south of Lake Okeechobee (Zwick and Carr 2006, p. 2). Even the
central Florida region, at what would be the northern limit of this
species' distribution, will be almost entirely urbanized (Zwick and
Carr 2006, p. 2). In an independent review of the FWC's biological
status report for the species, Fleming stated, ``Continued urbanization
of south Florida will undoubtedly have a negative impact on this bat''
(FWC 2011b, p. 3).
Loss of Forested Habitat
Loss of native forested habitat and roost sites are major threats
to the Florida bonneted bat. A highway construction project in Punta
Gorda in 1979 destroyed a roost tree (Belwood 1981, p. 412; 1992, p.
220). One museum specimen was originally discovered under a rock that
was turned over by a bulldozer clearing land (Robson 1989, p. 9).
Robson (1989, pp. 1-18) attributed the loss of native forested habitat,
reduced insect abundance (see Factor E), and the ``active persecution
of bats by humans'' (see Factor E) as the likely major impacts on the
Florida bonneted bat in Miami-Dade County. Similarly, Belwood (1992,
pp. 217, 220) indicated that bats in south Florida, including this
species, appear to have declined drastically in numbers in recent years
due to loss of roosting sites and effects of pesticides (see Factor E).
More recently, Timm and Genoways (2004, p. 861) stated that habitat
loss from development, in combination with other threats (i.e.,
pesticides and hurricanes, see Factor E), may have had a significant
impact upon the already low numbers of Florida bonneted bats.
Belwood (1992, p. 220) stated that forested areas are becoming rare
as a result of human encroachment and that this will severely affect
the forest occurrences of this species. Similarly, Robson (1989, p. 15)
indicated that pine rockland, live oak, and tropical hardwood hammocks
constituted most of the remaining, natural forest in the Miami area and
that these communities are essential to this species' survival. Belwood
(1992, p. 220) argued that tree cavities are rare in southern Florida
and competition for available cavities (e.g., southern flying squirrel
[Glaucomys volans], red-headed woodpecker [Melanerpes erythrocephalus],
corn snake [Elaphe guttata guttata]) is intense. She suggested that
nonurban natural areas such as ENP, Big Cypress/Fakahatchee areas, and
State WMAs may be the only areas where this species may be found in the
future, provided old trees with hollows and cavities are retained
(Belwood 1992, p. 220) (see Land Management Practices, below).
Approximately 90 percent of the forested habitats in Florida have
been altered or eliminated, and losses are expected to continue (Wear
and Greis 2002, p. 56). In the Southern Forest Resource Assessment,
Florida was identified as one of the areas expected to experience
substantial losses of forest in response to human population and
changes in income (Wear and Greis 2002, p. 164). In the Southern Forest
Futures Project, peninsular Florida is forecasted to lose the most
forest land (34 percent) of any of the 21 sections analyzed in the
southern United States (Wear and Greis 2011, p. 35).
Land Management Practices
Although species occurrences on conservation lands are inherently
more protected than those on private lands, habitat alteration during
management practices may impact natural roosting sites because the
locations of such sites are unknown. For example, removal of old or
live trees with cavities during activities associated with forest
management (e.g., thinning, pruning), prescribed fire, exotic species
treatment, or trail maintenance may inadvertently remove roost sites,
if such sites are not known. Loss of an active roost or removal during
critical life-history stages (e.g., when females are pregnant or
rearing young) can have severe ramifications, considering the species'
small population size and low fecundity (see Factor E).
Overall, occupied and potential habitat for the Florida bonneted
bat on forested or wooded lands, both private and public, continues to
be at risk due to habitat loss, degradation, and fragmentation from a
variety of sources. Additional searches for potential roosting sites in
forested and other natural areas are especially needed.
Loss of Artificial Structures
Since the Florida bonneted bat will use human dwellings and other
artificial structures, it is also vulnerable to habitat loss and
alteration in urban environments (Belwood 1992, p. 220; Timm and
Arroyo-Cabrales 2008, p. 1). Owre (1978, p. 43) stated that all recent
specimens had been collected within the suburbs of greater Miami from
structures built in the 1920s and 1930s. Owre (1978, p. 43) indicated
that three specimens were taken on the ground, one in a rocky field
that was being bulldozed, one next to sewer conduits piled near freshly
dug excavations, and one on a lawn near a university building in which
the bats roosted. Removal of buildings with spaces suitable for
roosting is a threat to this species (Timm and Arroyo-Cabrales 2008, p.
1). Robson (1989, p. 15) stated that seemingly innocuous activities
like destroying abandoned buildings and sealing barrel-
[[Page 61028]]
tile roof shingles may have a severe impact on remaining populations in
urban areas. Cyndi and George Marks (pers. comm. 2008) stated that
Florida bonneted bats can move into new buildings as well and ``the
fact that they adapt well to manmade structures has most likely been a
large factor in their decline'' (see Factor E). The use of buildings or
other structures inhabited by or near humans places bats at risk of
inadvertent or purposeful removal and displacement (see Factor E).
Climate Change and Sea Level Rise
Our analyses under the Act include consideration of ongoing and
projected changes in climate. The terms ``climate'' and ``climate
change'' are defined by the Intergovernmental Panel on Climate Change
(IPCC). The term ``climate'' refers to the mean and variability of
different types of weather conditions over time, with 30 years being a
typical period for such measurements, although shorter or longer
periods also may be used (IPCC 2007, p. 78). The term ``climate
change'' thus refers to a change in the mean or variability of one or
more measures of climate (e.g., temperature or precipitation) that
persists for an extended period, typically decades or longer, whether
the change is due to natural variability, human activity, or both (IPCC
2007, p. 78).
Scientific measurements spanning several decades demonstrate that
changes in climate are occurring, and that the rate of change has been
faster since the 1950s. Examples include warming of the global climate
system, and substantial increases in precipitation in some regions of
the world and decreases in other regions (for these and other examples,
see IPCC 2007, p. 30; and Solomon et al. 2007, pp. 35-54, 82-85).
Scientists use a variety of climate models, which include
consideration of natural processes and variability, as well as various
scenarios of potential levels and timing of greenhouse gas (GHG)
emissions, to evaluate the causes of changes already observed and to
project future changes in temperature and other climate conditions
(e.g., Meehl et al. 2007, entire; Ganguly et al. 2009, pp. 11555,
15558; Prinn et al. 2011, pp. 527, 529). Although projections of the
magnitude and rate of warming differ after about 2030, the overall
trajectory of all the projections is one of increased global warming
through the end of this century, even for the projections based on
scenarios that assume that GHG emissions will stabilize or decline.
Thus, there is strong scientific support for projections that warming
will continue through the 21st century, and that the magnitude and rate
of change will be influenced substantially by the extent of GHG
emissions (IPCC 2007, pp. 44-45; Meehl et al. 2007, pp. 760-764 and
797-811; Ganguly et al. 2009, pp. 15555-15558; Prinn et al. 2011, pp.
527, 529).
Various changes in climate may have direct or indirect effects on
species. These effects may be positive, neutral, or negative, and they
may change over time, depending on the species and other relevant
considerations, such as interactions of climate with other variables
(e.g., habitat fragmentation) (IPCC 2007, pp. 8-14, 18-19).
We use ``downscaled'' projections when they are available and have
been developed through appropriate scientific procedures, because such
projections provide higher resolution information that is more relevant
to spatial scales used for analyses of a given species (see Glick et
al. 2011, pp. 58-61, for a discussion of downscaling). With regard to
our analysis for the Florida bonneted bat, downscaled projections
suggest that sea-level rise is the largest climate-driven challenge to
low-lying coastal areas and refuges in the subtropical ecoregion of
southern Florida (U.S. Climate Change Science Program (CCSP) 2008, pp.
5-31, 5-32). Although not strictly tied to coastal areas, the Florida
bonneted bat uses, in part, forests and other habitats near sea level
in areas of south Florida where considerable habitat is projected to be
lost to sea level rise by 2100 (Saha et al. 2011, pp. 81-108). Three
subpopulations of the Florida bonneted bat occur in at-risk coastal
locations (Gore et al. 2010, pp. 1-2), and the effects of sea level
rise are expected to be a continual problem for species using coastal
habitats (Saha et al. 2011, p. 81).
Subsequent to the 2007 IPCC Report, the scientific community has
continued to model sea level rise. Recent peer reviewed publications
suggest increased acceleration of sea level rise. Observed sea level
rise rates are already trending along the higher end of the 2007 IPCC
estimates, and it is now widely predicted that sea level rise will
exceed the levels projected by the IPCC (Grinsted et al. 2010, p. 470;
Rahmstorf et al. 2012, p.1). Taken together, these studies support the
use of higher end estimates now prevalent in the scientific literature.
Recent studies have estimated a mean global sea level rise of 1 to 2 m
(3.3 to 6.6 ft) by 2100, based upon individual projections as follows:
0.75 m to 1.90 m (2.5 to-6.2 ft; Vermeer and Rahmstorf 2009), 0.8 m to
2.0 m (2.6 to 6.6 ft; Pfeffer et al. 2008), 0.9 m to 1.3 m (3 to 4.3
ft; Grinsted et al. 2010), 0.6 m to 1.6 m (2.0 to 5.2 ft; Jevrejeva et
al. 2010), and 0.5 m to 1.40 m (1.6 to 4.6 ft; The National Academy of
Sciences 2012).
When analyzed using NOAA's Sea Level Rise and Coastal Impacts
viewer (http://www.csc.noaa.gov/slr/viewer/#), we can generalize as to
the impact of a 1.8-m (5.9-ft) sea level rise (the maximum available
using this tool) on the areas currently used by the Florida bonneted
bat. This approach is a gross estimation, confounded by the fact that
no natural active roost sites are known and individuals are capable of
traveling large distances and likely have large home ranges. In
addition, it is a conservative estimate since large portions of the
species' occupied range fell into the category of ``area not mapped''
using this tool. A 1.8-m (5.9-ft) rise would inundate roughly half of
the locations where the species has been recorded or observed (see
Table 1, above), but not necessarily the entirety of each site. Within
the species' range, low-lying areas in Collier, Lee, Miami-Dade, and
Monroe Counties appear most vulnerable to inundation. In Collier
County, portions of FSPSP, PSSF, BCNP, Everglades City, and Naples will
likely be partially inundated. In Lee County, areas near the occupied
bat houses in North Fort Myers may be partially inundated. In Miami-
Dade County, three sites will likely be inundated and others in low-
lying areas are vulnerable. In Monroe County, coastal areas within ENP
will be impacted. In this analysis, it appears that occupied areas of
Charlotte, Polk, and Okeechobee Counties are the most secure, in terms
of remaining unaffected from inundation. In summary, much of low-lying,
coastal south Florida ``will be underwater or inundated with saltwater
in the coming century'' (CCSP 2008, p. 5-31). This means that large
portions of occupied, suitable, and potential roosting and foraging
habitat for the Florida bonneted bat in low-lying areas will likely be
either submerged or affected by increased flooding.
Climate change is likely to increase the occurrence of saltwater
intrusion as sea level rises (IPCC 2008, pp. 87, 103)). Since the
1930s, increased salinity of coastal waters contributed to the decline
of cabbage palm forests on the west coast of Florida (Williams et al.
1999, pp. 2056-2059), expansion of mangroves into adjacent marshes in
the Everglades (Ross et al. 2000, pp. 108, 110-111), and loss of pine
rockland in the Keys (Ross et al. 1994, pp. 144, 151-155). Saha et al.
2011 (pp. 81, 105) predicted changes in plant species composition and a
decline in the extent of coastal hardwood hammocks and buttonwood
forests in ENP before the
[[Page 61029]]
onset of inundation, based upon tolerance to salinity and drought. Such
changes in vegetation will likely impact the Florida bonneted bat,
since the species uses forested areas and coastal habitats.
Hydrology has a strong influence on plant distribution in these and
other coastal areas (IPCC 2008, p. 57). Such communities typically
grade from salt to brackish to freshwater species. Human developments
will also likely be significant factors influencing whether natural
communities can move and persist (IPCC 2008, p. 57; CCSP 2008, p. 7-6).
Climate change, human population growth, forest management, and land
use changes are also expected to increase water stress (water demand
exceeding availability) within areas of the south, and south Florida is
considered a hot spot for future water stress (Wear and Greis 2011, pp.
46-50). For the Florida bonneted bat, this means that some habitat in
coastal areas will likely change as vegetation changes and additional
human developments encroach. Any deleterious changes to important
roosting sites or foraging areas could further diminish the likelihood
of the species' survival and recovery.
In the southeastern United States, drier conditions and increased
variability in precipitation associated with climate change are
expected to hamper successful regeneration of forests and cause shifts
in vegetation types through time (Wear and Greis 2011, p. 58). In their
study on the impact and implications of climate change on bats, Sherwin
et al. (2012, p. 8) suggested that bats specialized in individual roost
sites (i.e., cave and tree roosts) at distinct life-history stages are
at great risk from changing vegetation and climatic conditions. Rebelo
et al. (2010, pp. 561-576) found that tree-roosting bats in Europe may
face a reduction in suitable roosts if the rate of climate change is
too rapid to allow the development of equivalent areas of mature
broadleaf forests in new `climatically suitable areas' as their range
extends northward. Decreases in forest regeneration may further limit
available roosting sites for the Florida bonneted bat or increase
competition for them.
Drier conditions and increased variability in precipitation are
also expected to increase the severity of wildfire events. Climate
changes are forecasted to extend fire seasons and the frequency of
large fire events throughout the Coastal Plain (Wear and Greis 2011, p.
65). Increases in the scale, frequency, or severity of wildfires could
also have severe ramifications on the Florida bonneted bat, considering
its forest-dwelling nature and general vulnerability due to its small
population size, restricted range, few colonies, low fecundity, and
relative isolation (see Factor E).
Climate changes may also affect foraging habitat and prey
availability. Increased plant water stress is likely to impact
vegetation community composition and chemical composition of plants,
which would likely affect insect availability and the timing of insect
availability to foraging bats (H. Ober, in litt. 2012). In one study,
Huberty and Denno (2004, pp. 1383-1398) examined water stress on plants
(e.g., changes in nitrogen, allelochemistry) and consequences for
herbivorous insects, examining parameters such as survivorship,
density, fecundity, and relative growth rate. Water stress in plants
was found to affect the population dynamics of herbivorous insects,
with varying effects depending upon insect guild (Huberty and Denno
2004, pp. 1383-1398). In another study, Von Holle et al. (2010, pp. 1-
10) found that climatic variability is leading to later seasonal
flowering of plants in Florida. Although the dietary needs of the
Florida bonneted bat are not understood, climate changes may affect
foraging habitat and insect availability in ways not readily apparent.
Alternative Future Landscape Models and Coastal Squeeze
The Florida bonneted bat is anticipated to face major risks from
coastal squeeze, which occurs when habitat is pressed between rising
sea levels and coastal development that prevents landward movement
(Scavia et al. 2002; FitzGerald et al. 2008; Defeo et al. 2009; LeDee
et al. 2010; Menon et al. 2010; Noss 2011). Habitats in coastal areas
(i.e., Charlotte, Lee, Collier, Monroe, Miami-Dade Counties) are likely
the most vulnerable. Although it is difficult to quantify impacts due
to uncertainties involved, coastal squeeze will likely result in losses
in roosting and foraging habitat for the Florida bonneted bat in
several areas.
Various model scenarios developed at the Massachusetts Institute of
Technology (MIT) have projected possible trajectories of future
transformation of the south Florida landscape by 2060 based upon four
main drivers: climate change, shifts in planning approaches and
regulations, human population change, and variations in financial
resources for conservation (Vargas-Moreno and Flaxman 2010, pp. 1-6).
The Service used various MIT scenarios in combination with available
acoustical data to project what may occur to occupied Florida bonneted
bat habitat in the future, assuming that all occupied areas are known,
that acoustical data represented approximate locations of colonies in
the future, and that projected impacts to colonies are solely tied to
roosting habitat. Potential impacts to foraging habitat were expected
but not analyzed, since foraging distances are not known. We
acknowledge that this analysis was crude and conservative (e.g.,
foraging habitat not analyzed; effects analyzed only up to 2060, the
maximum time period of the model scenarios). Actual outcomes may
substantially differ from that projected depending upon deviations in
the assumptions or estimated variables.
In the best-case scenario, which assumes low sea level rise, high
financial resources, proactive planning, and only trending population
growth, analyses suggest that four broad occupied areas may be lost.
Based upon the above assumptions, occupied areas in North Fort Myers,
the Ten Thousand Islands area, coastal portions of ENP (multiple
sites), and the Miami area (multiple sites) appear to be most
susceptible to future losses, with losses attributed to increases in
sea level and human population. In the worst-case scenario, which
assumes high sea level rise, low financial resources, a `business as
usual' approach to planning, and a doubling of human population, 10
broad occupied areas may be lost--the areas noted in the best-case
scenario above as well as some in BCNP (multiple sites), Naples,
Everglades City, mainland portions of ENP (multiple sites), Homestead,
and Coral Gables. Actual impacts may be greater or less than
anticipated based upon high variability of factors involved (e.g., sea
level rise, human population growth) and assumptions made.
Summary of Factor A
We have identified a number of threats to the habitat of the
Florida bonneted bat which have occurred in the past, are impacting the
species now, and will continue to impact the species in the future.
Habitat loss, fragmentation, and degradation, and associated pressures
from increased human population are major threats; these threats are
expected to continue, placing the species at greater risk. The species'
use of conservation areas tempers some impacts, yet the threats of
major losses of habitat remains. In natural or undeveloped areas, the
Florida bonneted bat may be impacted when forests are converted to
other uses
[[Page 61030]]
or when old trees with cavities are removed. Routine land management
activities (e.g., thinning, prescribed fire) may also impact unknown
roost sites. In urban areas, suitable roost sites may also be lost when
buildings are demolished or when structures are modified to exclude
bats. Uncertainty regarding the species' specific habitat needs and
requirements (i.e., location of roost sites) arguably contributes to
these threats, by increasing the likelihood of inadvertent impacts to
and losses of habitat. The effects resulting from climatic change,
including sea level rise and coastal squeeze, are expected to become
severe in the future and result in additional habitat losses, including
the loss of roost sites and foraging habitat. Although efforts are
being made to conserve natural areas and, in some cases, retain cavity
trees, the long-term effects of large-scale and wide-ranging habitat
modification, destruction, and curtailment will last into the future.
Therefore, based on our analysis of the best available information,
present and future loss and modification of the species' habitat is a
threat to the Florida bonneted bat throughout all of its range.
Factor B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Key features of the basic life history, ecology, reproductive
biology, and habitat requirements of many bats, including the Florida
bonneted bat, are unknown. Species-specific ecological requirements
have not been determined (e.g., natural roost sites, seasonal changes
in roosting habitat, dietary needs, seasonal changes in diet, prime
foraging habitat). The majority of information comes from examination
of dead specimens, chemical analyses of samples taken from dead
specimens, analysis of guano, and collection and analysis of
nonintrusive acoustical recordings. To our knowledge, those individuals
who have studied or are actively studying the Florida bonneted bat are
sensitive to its rarity and endemism (restricted range). Consequently,
collection for scientific and educational purposes is extremely
limited. We are not aware of any known commercial or recreational uses
for the species. For these reasons, we find that overutilization for
commercial, recreational, scientific, or educational purposes does not
currently pose a threat to the species, nor is it likely to do so in
the future.
Factor C. Disease or Predation
The effects of disease or predation are not well known. Given the
Florida bonneted bat's overall vulnerability, both disease and
predation could pose threats to its survival.
Disease
White-nose syndrome (WNS) is an emerging infectious disease
affecting insectivorous, cave-dwelling bats. It was first documented in
2006, in caves west of Albany, New York. Since its discovery, WNS has
spread rapidly throughout the eastern and central United States and
southeastern Canada, killing millions of bats. It is expected to
continue spreading westward and southward. By June 2012, WNS had been
confirmed in well over 200 caves and mines within 20 States and 4
Canadian provinces (J. Coleman, pers. comm. 2012). As of June 2013, the
number of affected sites is rapidly changing, and bats with WNS have
now been confirmed in 22 States and 5 Canadian provinces (http://www.whitenosesyndrome.org/about/where-is-it-now). It has not yet been
documented in Florida.
WNS is caused by the cold-loving fungus, Geomyces destructans, a
newly described fungus, and is named after the white fungal growth that
often occurs on the muzzle of affected bats (Gargas et al. 2009, pp.
147-154; Lorch et al. 2011, pp. 376-379). In North America, G.
destructans appears to infect bats only during winter hibernation.
Mortality rates have been observed to vary by species and site, but
have been as high as 100 percent at some hibernacula (winter bat
roosts).
WNS has been recorded in seven North American bat species, all of
which are known to hibernate in caves and mines. WNS and G. destructans
have not been detected in bats that typically live outside of caves,
such as eastern red-bats (Lasiurus borealis), and the fungus is
believed to need the cave environment to survive. Because the Florida
bonneted bat spends its entire life cycle outside of caves and mines
and in subtropical environments where no torpor or hibernation is
required, we do not anticipate that it will be adversely affected by
WNS. However, since the fungus is new to science and North America, it
is not known how it may evolve or change in the future.
Prior to the discovery of WNS, infectious diseases had rarely been
documented as a large-scale cause of mortality in bat populations and
had not been considered a major issue (Messenger et al. 2003 as cited
in Jones et al. 2009, p. 108). Jones et al. (2009, pp. 108-109)
contended that because increased environmental stress can suppress the
immune systems of bats and other animals, increased prevalence of
diseases may be a consequence of altered environments (i.e., bats may
be more susceptible to disease if they are stressed by other threats).
These authors contended that bats are excellent potential bioindicators
because they are reservoirs of a wide range of emerging infectious
diseases whose epidemiology may reflect environmental stress. Jones et
al. (2009, p. 109) suggested that an increased incidence of disease in
bats may be an important bioindicator of habitat degradation in
general. Sherwin et al. (2012, p. 14) suggest that warming temperatures
associated with climate change may increase the spread of disease
(along with other impacts; see Factor E), which could cause significant
mortalities to bat populations in general.
At this time, it is difficult to assess whether disease is
currently or likely to become a threat to the Florida bonneted bat.
With anticipated climatic changes and increased environmental stress,
it is possible that disease will have a greater impact on the Florida
bonneted bat in the future.
Predation
In general, animals such as owls, hawks, raccoons, skunks, and
snakes prey upon bats (Harvey et al. 1999, p. 13). However, few animals
consume bats as a regular part of their diet (Harvey et al. 1999, p.
13). There is only one record of natural predation on the Florida
bonneted bat (Timm and Genoways 2004, p. 860). A skull of one specimen
was found in a regurgitated owl pellet at the FSPSP in June 2000 (Timm
and Genoways 2004, pp. 860-861; C. Marks, pers. comm. 2006a; Marks and
Marks 2008a, p. 6; M. Owen, pers. comm. 2012a, 2012b).
Although evidence of predation is lacking, the species is
presumably affected by some level of predation from native wildlife
(e.g., hawks, owls, raccoons, rat snakes) and the large number of
introduced and nonnative reptiles (e.g., young Burmese pythons, boa
constrictors) (Krysko et al. 2011; M. Ludlow, in litt. 2012; R. Timm,
in litt. 2012). Several species of nonnative, giant constrictor snakes
have become established in Florida, causing major ecological impacts
(http://www.fort.usgs.gov/FLConstrictors/ 77 FR 3330, January 23,
2012). Giant constrictors are habitat generalists, can grow and
reproduce rapidly, and are arboreal when young, placing birds and
arboreal mammals, such as bats, at risk (http://www.fort.usgs.gov/FLConstrictors/). Given the small population of the Florida bonneted
bat, it is possible that the loss to snake predation is under
appreciated now or this may become more of a threat in the future (M.
Ludlow, in litt. 2012; R.
[[Page 61031]]
Timm, in litt. 2012). Some efforts to control nonnative snakes and
other species are being made on some conservation lands (e.g., ENP;
Harvey et al. 2013; http://www.fort.usgs.gov/FLConstrictors), but we do
not have data on how these efforts may be impacting the Florida
bonneted bat.
Due to limited information, we are not able to determine the extent
to which predation may be impacting the Florida bonneted bat at this
time. However, given the species' apparent small population size and
overall vulnerability, it is reasonable to assume that predation is a
potential threat, which may increase in the future.
Summary of Factor C
Disease and predation have the potential to impact the Florida
bonneted bat's continued survival, given its few occupied areas,
apparent low abundance, restricted range, and overall vulnerability. At
this time, we do not have evidence to suggest that disease or predation
is currently having species-level impacts on the Florida bonneted bat.
However, given the uncertainties (e.g., evolving disease) and factors
involved (e.g., more introduced predators), coupled with the general
vulnerability of the species, we consider both disease and predation to
be potential threats to the Florida bonneted bat.
Factor D. The Inadequacy of Existing Regulatory Mechanisms
Despite the fact that regulatory mechanisms provide several
protections for the Florida bonneted bat, Federal, State, and local
laws have not been sufficient to prevent past and ongoing impacts to
the species and its habitat within its current and historical range.
The taxon was originally listed as endangered in the State of
Florida as the Florida mastiff bat (Eumops glaucinus floridanus)
(F.A.C., chapter 68). As such, it is afforded protective provisions
specified in F.A.C. chapter 68A-27 (68A-27.0011 and 68A-27.003). This
designation prohibits any person from pursuing, molesting, harming,
harassing, capturing, possessing, or selling this species, or parts
thereof, except as authorized by specific permit, with permits being
issued only when the permitted activity will clearly enhance the
survival potential of the species. The protection afforded the Florida
bonneted bat by the State of Florida primarily prohibits direct take of
individuals (J. Gore, pers. comm. 2009). However, there is no
substantive protection of habitat or protection of potentially suitable
habitat at this time.
As a consequence of the revision of the FWC's listing
classification system, the former classification levels of Florida's
endangered and threatened species were re-classified as a single level,
named ``State-designated Threatened,'' and include any species that met
the FWC criteria based on the IUCN criteria for a vulnerable species.
All species formerly listed as endangered and reclassified as State-
designated Threatened maintain the protections of the former endangered
classification. Hence, the Florida bonneted bat's status technically
changed on November 8, 2010, but the species' original protective
measures remained in place (F.A.C. chapter 68A-27.003, amended). As
part of the FWC's revision of its classification system, biological
status review reports were prepared for numerous imperiled species in
Florida, including the Florida bonneted bat. Based upon a literature
review and the biological review group's findings, FWC staff
recommended that the Florida bonneted bat remain listed as a threatened
species (FWC 2011a, p. 5). The biological status review recognized the
taxon as the Florida bonneted bat, and the State's current threatened
and endangered list uses both names, Florida bonneted (mastiff) bat,
Eumops (=glaucinus) floridanus. The FWC's draft Species Action Plan for
the species uses the name E. floridanus (FWC 2013, pp. 1-43).
As part of the FWC's revision to Florida's imperiled species rule,
management plans will be developed for all species (F.A.C. chapter 68A-
27), including the Florida bonneted bat. One component of these
management plans is to include needed regulations and protections that
are not provided in the current rule (M. Tucker, in litt. 2012). A
first draft for the Florida bonneted bat management plan is in
development (J. Myers, pers. comm. 2012c; M. Tucker, in litt. 2012).
When completed, the management plan should allow for tailored
protections for the species, which may improve the ability of FWC to
address habitat issues in addition to take of individuals (M. Tucker,
in litt. 2012). Objectives of the State plan will be to reverse threats
causing the decline of the species (FWC, in litt. 2012).
Humans often considered bats to be ``nuisance'' species when they
occur in or around human dwellings or infrastructure (see Factor E,
below). The rules for taking of nuisance wildlife are provided under
F.A.C. chapter 68A-9.010. Under these rules, property owners can take
nuisance wildlife or may authorize another person to take nuisance
wildlife on their behalf. Although these rules do not authorize the
taking of species listed under F.A.C. chapter 68A-27 (without an
incidental take permit from the State), these rules do allow other bat
species to be taken under certain circumstances. These include when:
(1) The take is incidental to the use of an exclusion device, a device
which allows escape from and blocks reentry into a roost site located
within a structure, or incidental to the use of a registered chemical
repellant, at any time from August 15 to April 15; or (2) the take is
incidental to permanent repairs that prohibit the egress of bats from a
roost site located within a structure, provided an exclusion device is
used as above for a minimum of four consecutive days or nights for
which the low temperature is forecasted to remain above 10 [deg]C
(50[emsp14][deg]F) prior to repairs and during the time period
specified. F.A.C. chapter 68A-9.010 provides the methods that may not
be used to take nuisance wildlife, including any method prohibited
pursuant to section 828.12 of the Florida Statutes (Florida Cruelty to
Animals Statutes).
Use of bat exclusion devices or any other intentional device or
materials at a roost site that may prevent or inhibit the free ingress
or egress of bats is prohibited from April 16 through August 14. While
these restrictions help to limit potential impacts during the maternity
season for many bat species in Florida, regulations do not require
definitive identification of the bat species to be excluded prior to
the use of the device. In addition, it is not clear if this time period
is broad enough to prevent potential impacts to the Florida bonneted
bat, which is possibly polyestrous and more tropical in nature, with a
potentially prolonged sensitive time window where females and young are
especially vulnerable. Pregnant Florida bonneted bats have been found
in June through September (Marks and Marks 2008a, p. 9), and a second
birthing season can occur possibly in January-February (Timm and
Genoways 2004, p. 859; FBC 2005, p. 1). During the early portion of the
maternal period, females may give birth to young and leave them in the
roost while making multiple foraging excursions to support lactation
(Marks and Marks 2008a, pp. 8-9). Therefore, despite regulations
restricting the use of exclusion devices, it is still possible that use
of such devices can affect the species during sensitive time periods,
including possible impacts to pregnant females, newborns, or juvenile
pups.
The FWC, FBC, Bat Conservation International, and other groups
maintain a list of qualified exclusion devices, but it is not clear how
often work is performed by recommended personnel
[[Page 61032]]
or if it is in accordance with State regulations. It is also not clear
if those who install exclusion devices can readily distinguish between
Florida bonneted bats and other bat species in Florida (M. Tucker,
pers. comm. 2012). Despite regulations, in some cases, nuisance bats
are likely being removed by nuisance wildlife trappers through methods
that are not approved (e.g., removed from roosts with vacuum cleaner-
like apparatuses) or excluded during time periods that are not
permitted (e.g., inside the maternity season) (A. Kropp, FWC, pers.
comm. 2009). Pest control companies unaware of or not complying with
the regulations that apply to bats have been known to remove them
through methods other than legal exclusions (FWC 2013, p. 9). Private
landowners and individual property owners may also be unaware of
regulations.
In addition, there are discrepancies between legislation passed by
the FDACS, which classifies bats as rodents, and the current FWC
nuisance wildlife regulations above (Florida Bat Working Group [FBWG]
2009, p. 3). According to the State's Structural Pest Control Act
(Florida Statutes, chapter 482) bats may be considered pests, and pest
control including methods to prevent, destroy, control, or eradicate
pests in, on, or under a structure, lawn, or ornamental are allowable
under certain rules and provisions (FDACS, in litt. 2012). The FDACS
regulates the control of ``commensal rodents'' (rats and mice) in or
near structures and the use of pesticides, including the pesticides
used for the control of nuisance wildlife (i.e., poisons and
repellents) (FDACS, in litt. 2012). However, FDACS does not regulate
commercial trapping or removal of wildlife, including bats, as these
are protected under F.A.C. chapter 68A-9.010 (FDACS, in litt. 2012).
The use of poisons on bats is not permitted. The use of a repellant
(e.g., naphthalene) by professional pest control or wildlife management
personnel to remove bats from a structure requires a pest control
operator's license (FDACS, in litt. 2012).
Bat advocacy groups and others are concerned over the lack of
awareness of the regulations among people paid to perform exclusions
(FBWG 2009, p. 3; FWC 2013, p. 21). Education is needed about the dates
during which exclusion is prohibited for nuisance wildlife trappers,
pest control companies, law enforcement, county health departments, and
local animal control (FBWG 2010, p. 3). The FDACS is currently
developing a limited license for those individuals or companies that
conduct wildlife removal services in or near structures (M. Tucker, in
litt. 2012). To obtain this license, operators will be required to
complete an educational program and pass a test based on a training
manual in development by staff with the University of Florida-Institute
of Food and Agricultural Sciences (M. Tucker, in litt. 2012). The
manual will include information on proper exclusion techniques and
existing regulations protecting bats during the maternity season (M.
Tucker, in litt. 2012). The FDACS, with assistance from other agencies,
offered to develop an informational bulletin on the Florida bonneted
bat that can be distributed to pest control operators directly or
during training for certification or renewal (FDACS, in litt. 2012).
Additional educational efforts are underway. To better address
violations of the maternity season and exclusion rule, FWC is training
law enforcement officers (M. Tucker, in litt. 2012). Training on the
importance of bats and the rules relating to exclusions has been
provided to some officers in the northern part of the State, and an
online training module is being developed as part of the FWC law
enforcement educational curriculum that all officers must complete (M.
Tucker, in litt. 2012). The FWC, FDACS, Service, and other partners are
also planning to increase awareness among land managers, environmental
professionals, pest control operators, wildlife trappers, county health
departments, local animal control, and others who may be in a position
to have an impact on bat habitat or bat roosts (FDACS, in litt. 2012).
It is not clear to what extent training programs will be supported in
the future or how effective efforts to raise awareness will be in
reducing violations.
With regard to Federal lands, the NPS manages the natural resources
on its lands (e.g., BCNP, ENP) in accordance with NPS-specific
statutes, including the NPS Organic Act (16 U.S.C. 1 et seq.), as well
as other general environmental laws and applicable regulations. The
Florida Panther NWR operates under the Fish and Wildlife Act of 1956
(16 U.S.C. 742a et seq.), the Endangered Species Act, and the Refuge
Administration Act (16 U.S.C. 668dd-668ee). With regard to State lands,
all property and resources owned by FDEP are generally protected from
harm in chapter 62D-2.013(2), and animals are specifically protected
from unauthorized collection in chapter 62D-2.013(5), of the Florida
Statutes. At Babcock-Webb WMA, the FWC is the lead managing agency,
with FFS as a cooperating agency, and is responsible for operation
through a lease agreement; management is derived under article IV,
section 9 of the Florida Constitution, and guidance and directives
under the Florida Statutes (FWC 2003, p. 4). At PSSF, the FFS manages
the forest using the multiple-use concept, providing a balance for
recreational, environmental, and resource use needs, including forest
and wildlife management. Miami-Dade County Park lands are fragmented,
heavily used, and also try to balance recreational, natural, and
cultural uses.
The Florida bonneted bat's presence on Federal, State, and county
lands provides some protection, but does not insulate it from many
threats (see Factor A and Factor E). These lands provide clear
conservation benefits to the species, but protections may be limited in
extent (e.g., within the boundaries of the parcel). In some cases,
conservation benefits for the Florida bonneted bat may not be fully
realized on conservation lands due to various missions of individual
parcels and the demands of balancing the management of other wildlife
and habitats or multiple purposes and uses (e.g., recreation). Even
where wildlife conservation is the primary purpose, routine land
management practices (e.g., prescribed fire) can cause the loss of
roost sites, especially since locations of natural roosts are unknown
(see Factor A). Human use can cause disturbance and the use of
pesticides may increase the likelihood of direct exposure or may impact
the prey base (see Factor E).
Collecting permits can be issued ``for scientific or educational
purposes.'' Permits are required from the FWC for scientific research
on the Florida bonneted bat. For work on Federal lands (e.g., ENP,
BCNP), permits are required from the NPS or the Service, if work is on
NWRs. For work on State lands, permits are required from FDEP, FFS,
FWC, or Water Management District, depending upon ownership and
management. Permits are also required for work on county-owned lands.
Summary of Factor D
Despite existing regulatory mechanisms, the Florida bonneted bat
remains at risk due to the effects of a wide array of threats (see
Factors A and E). Based on our analysis of the best available
information, we find that existing regulatory measures, due to a
variety of constraints, do not provide adequate protection, and, in
some instances, may be harmful (i.e., taking of bats as ``nuisance''
wildlife). Educational efforts and training should help to raise
awareness and address some violations of existing regulations. When
finalized, the FWC's Florida bonneted bat management plan may
[[Page 61033]]
contain additional measures that can help protect habitat. However, we
do not have information to indicate that the aforementioned regulations
and programs, which currently do not offer adequate protection to the
Florida bonneted bat, will be revised and sufficiently supported, so
that they would be adequate to provide protection for the species in
the future. Therefore, we find that the existing regulatory mechanisms
are inadequate to address threats to the species throughout all of its
range.
Factor E. Other Natural or Manmade Factors Affecting Its Continued
Existence
In general, bat populations are in decline due to their sensitivity
to environmental stresses and other factors, such as slow reproductive
rates (Jones et al. 2009, pp. 93-115). The Florida bonneted bat is
likely affected by a wide array of natural and anthropogenic threats,
operating singly or synergistically, and in varying immediacy,
severity, and scope.
Inadvertent and Purposeful Impacts From Humans
In general, bats using old or abandoned and new dwellings are at
significant risk. Bats are often removed when they are no longer
tolerated by humans or inadvertently killed or displaced when
structures are demolished. Adverse human impacts on bats involve direct
killing, persecution, vandalism, and disturbance of hibernating and
maternity colonies (Harvey et al. 1999, p. 13). Belwood (1992, p. 217)
indicated that bats in south Florida appeared to decline drastically in
years just prior to that publication. Unpublished data by Belwood from
a 1982 survey of 100 pest control companies on the southeastern coast
of Florida showed that requests to remove ``nuisance'' bats from this
area all but ceased in the 20 years prior to that publication (Belwood
1992, p. 217). Homeowners and professionals use a variety of methods to
remove bats, including lethal means (C. Marks and G. Marks, pers. comm.
2008). Even when attempts are made to remove bats humanely, bats may be
sealed into buildings (C. Marks and G. Marks, pers. comm. 2008).
Despite regulations and efforts to raise awareness (see Factor D,
above), in some situations, bats are still likely removed through
inhumane and prohibited methods (e.g., removed from roosts with vacuum
cleaner-like apparatuses) and excluded from artificial roost sites
during sensitive time periods (e.g., inside the maternity season before
young are volant (capable of flying)) (A. Kropp, pers. comm. 2009).
Pest control companies unaware of or not in compliance with the
regulations that apply to bats have been known to remove them through
methods other than legal exclusions (FWC 2013, p. 9). Such activities
can result in direct mortality or injury of adults, juveniles,
dependent newborn pups, or fetuses, if pregnant females are affected.
In some cases, excluded individuals may not be able to readily locate
other suitable roosts (due to competition with other species, lack of
availability, or other factors). Since the breeding season of the
Florida bonneted bat is uncertain and adults may have young outside of
the typical maternity season, the FWC's draft species action plan
recommends that individuals consult with the FWC before excluding
Florida bonneted bats from a roost at any time of the year (FWC 2013,
p. 10).
In his dissertation on the ecological distribution of bats in
Florida, Jennings (1958, p. 102) stated that Florida bonneted bats are
encountered more often by humans than other bat species known to
frequent the Miami area. He attributed this to the species' habits,
which make it more conducive to discovery by humans. Jennings (1958, p.
102) noted, ``Some individuals were taken in shrubbery by gardners
[sic], some flew into houses at dusk and other isolated individuals
were taken under conditions indicating injury of some kind.'' The
Florida bonneted bat's ability to adapt well to manmade structures
contributes to its vulnerability and has likely been a factor in its
decline (C. Marks and G. Marks, pers. comm. 2008). Since roosting sites
are largely unknown, the potential to remove and exclude Florida
bonneted bats from human dwellings and artificial structures, either
inadvertently or accidentally, is high. Despite regulatory protections
provided under Florida law (see Factor D, above), direct and indirect
threats from humans continue, especially in urban, suburban, and
residential areas.
Similarly, Robson (1989, p. 15) stated that urban development has
resulted in the persecution of bats wherever they come in contact with
humans: ``Seemingly innocuous activities like removing dead pine or
royal palm trees, pruning landscape trees (especially cabbage palms),
sealing barrel-tile roof shingles with mortar, destroying abandoned
buildings, and clearing small lots of native vegetation cumulatively
may have a severe impact on remaining populations in urban areas''
(Robson 1989, p. 15). As the species may also use palm fronds for
roosting, the trimming of fronds and removal of mature palm trees for
landscaping may negatively impact individuals (K. Gillies, in litt.
2012). Harvey et al. (1999, p. 13) indicated that disturbance to summer
maternity colonies of bats is extremely detrimental. In general,
maternity colonies of bats do not tolerate disturbance, especially when
flightless newborns are present (Harvey et al. 1999, p. 13). Newborns
or immature bats may be dropped or abandoned by adults if disturbed
(Harvey et al. 1999, p. 13). Disturbance to maternity colonies of the
Florida bonneted bat may be particularly damaging because of this
species' low fecundity and low abundance. In short, wherever this
species occurs in or near human dwellings or structures, it is at risk
of inadvertent or purposeful removal, displacement, and disturbance.
Routine maintenance and repair of bridges and overpasses is a
potential threat. Bats can use highway structures either as day or
night roosts (Keeley and Tuttle 1999, p. 1). An estimated 24 of the 45
species of bats in the United States have been documented to use
bridges or culverts as roosts, and 13 other bat species are likely to
use such structures based upon their known roosting preferences (Keeley
and Tuttle 1999, p. 1). To date, the Florida bonneted bat has not been
documented to use these structures. However, a large colony of
Brazilian free-tailed bats was documented using the I-75 overpass at
the entrance of Babcock-Webb WMA, and a single Florida bonneted bat
call was recorded within 1.6 km (1.0 mi) of this overpass (S. Trokey,
pers. comm. 2008c). Given the species' flight capabilities and roosting
behaviors, the Florida bonneted bat could use this overpass or other
such structures (C. Marks and G. Marks, pers. comm. 2008; S. Trokey,
pers. comm. 2008c). The colony of Brazilian free-tailed bats was
excluded from the overpass in October 2011, prior to a widening project
on I-75, after the Florida Department of Transportation (FDOT)
coordinated the exclusion with FWC and the FBC (FWC, in litt. 2012).
The FWC had also constructed a community bat house near the overpass in
2009, to provide an alternate roost site (J. Morse, pers. comm. 2010).
Although it is not known if Florida bonneted bats will use community
bat houses, space was included to accommodate larger-bodied bats in
that structure (J. Morse, pers. comm. 2010). To date, the species has
not been found in the large community bat house at this site.
Maintenance and repair of bridges and overpasses or other
infrastructure may impact this species. For example, when bridges and
overpasses are
[[Page 61034]]
cleaned, bats may be subjected to high water pressure from hoses, which
likely results in injury or death (C. Marks, pers. comm. 2007).
Incidences involving high pressure water hoses have reportedly
decreased in Florida, and the FDOT is working with FWC to increase
their efforts to protect bats during maintenance and repair activities
at bridge sites with bats (FWC, in litt. 2012).
Competition for Tree Cavities
Suitable natural roost sites in south Florida appear limited, and
competition for available tree cavities may be greater now than
historically. In 1992, Belwood (1992, p. 220) stated that tree cavities
are rare in southern Florida and that competition for available
cavities from native wildlife (e.g., southern flying squirrel, red-
headed woodpecker, corn snake) was intense. Competition for cavities
since that time has presumably increased, due largely to continued loss
of cavity trees and habitat (see Factor A, above) and the influx of
nonnative or introduced species, which vie for available roosting or
nesting locations. Native wildlife and dozens of other nonnative or
introduced species (e.g., European starlings, black rats, Africanized
honey bees) in south Florida also now compete for tree cavities for
nesting, roosting, or other uses (W. Kern, Jr., in litt. 2012; M.
Ludlow, in litt. 2012).
In addition, numerous species of nonnative birds now occur in
Florida, and many are cavity nesters. More than 30 species of parrots
and 2 to 3 species of mynahs observed in the wild in south Florida use
cavities, and some may be competing with the Florida bonneted bat and
other native wildlife, for available natural or artificial structures
(W. Kern, Jr., in litt. 2012; http://myfwc.com/wildlifehabitats/nonnatives/birds/). Africanized honey bee hybrids, established in
Florida in 2005, are having significant impacts on cavity-nesting
wildlife throughout their expanding range in Central America, South
America, the Caribbean, and southeastern United States (Kern, Jr. 2011,
pp. 1-4; W. Kern, Jr., in litt. 2012). Africanized honey bee hybrids
now occupy the entire range of the Florida bonneted bat (W. Kern, Jr.,
in litt. 2012).
In summary, the extent of competition for cavity trees in south
Florida is not well understood. It appears that cavity trees are
limited and competition is greater now than historically. Despite the
lack of data, the possibility certainly exists for the Florida bonneted
bat to be impacted by competition for tree cavities from native or
nonnative wildlife.
Proposed Wind Energy Facilities
Wind power is one of the fastest growing sectors of the energy
industry (Horn et al. 2008, p. 123; Cryan and Barclay 2009, p. 1330),
and the development of wind energy facilities in Florida may be of
particular concern for the Florida bonneted bat as demand increases.
Migratory, tree-dwelling, and insectivorous bat species are being
killed at wind turbines in large numbers across North America (Kunz et
al. 2007, pp. 317-320; Cryan and Barclay 2009, pp. 1330-1340). Although
it is not clear why such species are particularly susceptible (Boyles
et al. 2011, p. 41), Kunz et al. (2007, pp. 315-324) proposed 11
hypotheses for the large numbers of fatalities at wind energy
facilities. Some of these include attraction to tall structures as
potential roost sites, attraction to enhanced foraging opportunities
(e.g., insects attracted to heat of turbines), echolocation failure,
electromagnetic field disorientation, and decompression (rapid pressure
changes causing internal injuries or disorientation of bats while
foraging). Similarly, Cryan and Barclay (2009, pp. 1330-1340)
categorized the causes of fatalities into two categories: proximate,
which explain the direct means by which bats die, and ultimate, which
explain why bats come close to turbines.
Based upon data modified from Johnson (2005 as cited in Arnett et
al. 2008, p. 64), researchers found that the Brazilian free-tailed bat
comprised 85.6 percent of bat mortalities noted at a wind energy
facility in Woodward, Oklahoma, and 41.3 percent of bat mortalities at
a High Wind, California, wind energy facility. Since the Florida
bonneted bat is also a free-tailed bat, it may demonstrate some similar
behaviors that place it at risk when encountering wind energy
facilities.
Bat mortalities at wind energy facilities may be seasonal in nature
(Johnson 2005, as cited in Kunz et al. 2007, p. 317). Most documented
mortalities in North America occurred between late summer and early
fall (Johnson 2005, as cited in Arnett et al. 2008, p. 66); Kunz et al.
2007, p. 317; Arnett et al. 2008, pp. 65-66). Taller turbines with
greater rotor-swept areas may be responsible for more bat mortalities
than shorter turbines with smaller rotor-swept areas (Arnett et al.
2008, p. 68). Bat mortalities are absent where turbines are not
spinning, indicating that bats do not strike stationary blades or
towers (Kerns et al. 2005, p. 91). Fatalities at wind energy facilities
tend to occur when wind speeds are <6m/second (19.7 ft/second) (Kerns
et al. 2005, p. 76). Bat mortalities were also negatively correlated
with rain (Kerns et al. 2005 p. 76). It should be noted, however, that
mortality monitoring at wind energy facilities is not standardized, and
there is a paucity of data for analysis. Most studies include less than
a full field season and may miss significant bat mortality events.
Differences between sites including scavenging rates, carcass
detection, and observer bias may all contribute to variations in bat
mortality records (Arnett et al. 2008, pp. 71-72).
The cause of bat mortality at wind energy facilities is not a
simple one of direct contact with blades or towers. Baerwald et al.
(2008, pp. 695-696) found that barotrauma is the cause of death in a
high proportion of bats found at wind energy facilities. Barotrauma
involves tissue damage to air-containing structures (such as lungs)
caused by rapid or excessive pressure change; wind turbine blades may
create zones of low pressure as air flows over them. In their
examination, Baerwald et al. (2008, pp. 695-696) found 90 percent of
the bat fatalities involved internal hemorrhaging consistent with
barotrauma, suggesting that even if echolocation allows for bats to
detect and avoid turbine blades, they may be incapacitated or killed by
internal injuries caused by rapid pressure reductions that they cannot
detect. Baerwald et al. (2008, pp. 695-696) suggested that the
differences in respiratory anatomy between bats and birds may explain
the higher incidence of bat fatalities from wind energy facilities (see
also Barclay et al. 2007, pp. 381-387). In short, the large pliable
lungs of bats expand when exposed to sudden drop in pressure, causing
tissue damage, whereas birds' compact, rigid lungs do not respond in
the same manner (Baerwald et al. 2008, pp. 695-696).
Wind turbine facilities are being planned for sites east and west
of Lake Okeechobee, and these may have an impact on the Florida
bonneted bat (M. Tucker, in litt. 2012). One proposed facility in
Glades County is roughly 14.5 km (9 mi) south of locations where the
species was recorded on the Kissimmee River in 2008 (M. Tucker, in
litt. 2012). In 2011, ``possible'' Florida bonneted bat calls were also
recorded on the proposed project site (C. Coberly, pers. comm. 2012).
Potential impacts from this proposed facility cannot be accurately
assessed at this time because it is not clear that the species uses the
site (i.e., occurs on site or moves to it during activities such as
foraging). The other proposed facility in Palm Beach
[[Page 61035]]
County has not recorded Florida bonneted bat calls on site (C. Newman,
pers. comm. 2012), and this county is not part of the species' known
historical or current range. Both wind energy development companies
have indicated that areas around Lake Okeechobee are the most suitable
sites in Florida for wind development, and if successfully developed,
additional sites could be proposed, increasing the risk of impacts from
wind energy to the Florida bonneted bat (M. Tucker, in litt. 2012).
While bat fatalities from wind energy facilities are well
documented, potential impacts to the Florida bonneted bat are difficult
to evaluate at this time, partly due to the uncertainty involving many
factors (e.g., location of facilities, operations, foraging distance).
Certain aspects of the species' status and life history may increase
vulnerability to impacts from wind energy facilities. The species'
small population and low fecundity make any additional potential
sources of mortality cause for concern. The species' high and strong
flight capabilities and fast-hawking foraging behavior may increase
risk. Conversely, as the species is nonmigratory, potential impacts
from wind energy facilities may not be as great in magnitude as perhaps
other bat species that are migratory. Implementation of the Service's
new land-based wind energy guidelines may also help to avoid and
minimize some impacts (Service 2012, pp. 1-71).
Pesticides and Contaminants
The impacts of pesticides and other environmental contaminants on
bat species are largely unstudied, particularly in the case of the
Florida bonneted bat. The life history of the Florida bonneted bat may
make it susceptible to pesticide exposure from a variety of sources.
Mosquito control spraying activities commonly begin at dusk when
mosquitoes are most active (http://www.miamidade.gov/publicworks/mosquito-spraying.asp). Because the Florida bonneted bat forages at
dusk and after dark, the possibility exists for individuals to be
directly exposed to airborne mosquito control chemicals or to consume
invertebrates containing pesticide residues from recent applications.
Additionally, because the Florida bonneted bat has been documented to
roost in residential areas (Belwood 1992, pp. 219-220), it is possible
for individuals to be exposed, either directly or through diet, to a
variety of undocumented, localized pesticide applications conducted by
homeowners. The potential exposure to or impacts of agricultural
chemical application on the Florida bonneted bat in Florida are largely
unknown.
Organochlorine (OC) pesticides have been linked to lethal effects
in bats (Clark et al. 1978, p. 1358; Clark et al. 1983, pp. 215-216;
O'Shea and Clark 2002, p. 239). Such pesticides have not been
registered for use in the United States for several decades, but due to
the extreme ability of OCs to persist in the environment, residues are
still detectable in soil and sediment in some locations in south
Florida. The possibility exists that the Florida bonneted bat may
consume invertebrates with elevated OC concentrations in areas with
substantial OC environmental concentrations, though this scenario would
be limited to specific sites and would not be expected to be a
widespread threat. No studies have been conducted that attempt to
assess the historical impact of OC pesticides on the Florida bonneted
bat.
Currently, OC pesticides have largely been replaced with OP,
carbamate, and pyrethroid pesticides. Carbamate and OP pesticides act
as cholinesterase inhibitors and are generally more toxic to mammals
than OC pesticides. However, they are not as persistent in the
environment and do not tend to bioaccumulate in organisms. Despite this
lack of persistence, Sparks (2006, pp. 3-4, 6-7) still found OP
residues in both bats and guano in Indiana and suspected that the
residues originated from consuming contaminated insects. Pyrethroids,
one of which is permethrin, are commonly used mosquito control
pesticides in south Florida that display greater persistence than OP
and carbamate pesticides, but still degrade much more rapidly than OC
pesticides and are believed to exhibit low toxicity to mammals.
Grue et al. (1997, pp. 369-388) reviewed the sublethal effects of
OPs and carbamates on captive small mammals and birds and found
impaired thermoregulation, reduced food consumption, and reproductive
alterations. Clark (1986, p. 193) observed a depression in
cholinesterase activity in little brown bats following both oral and
dermal application of the OP pesticide methyl parathion. Bats with
reduced cholinesterase activity may suffer loss of coordination,
impaired echolocation, and elongated response time. Alteration of
thermoregulation could have serious ramifications to bats, given their
high metabolic and energy demands (Sparks 2006, pp. 1-2). Reduced
reproductive success would be of concern because the Florida bonneted
bat already displays a low reproductive rate (Sparks 2006, p. 2). In
order to accurately evaluate the impact of such pesticides on the
Florida bonneted bat, additional work characterizing both pesticide
exposure and effects in bats is needed.
A reduction in the number of flying insects is a potential
secondary effect to consider when evaluating the impact of pesticides
on the Florida bonneted bat. In his status survey for the Florida
bonneted bat, Robson (1989, p. 15) suggested that mosquito control
programs are contributing to reduced food supplies for bats. Robson
(1989, p. 14) attributed the general reduced activity of bats along the
southeastern coastal ridge to the reduction of forested habitat and
reduced insect abundance. Although insect activity was not measured,
Robson (1989, p. 14) noted that the ``lack of insects on the
southeastern coastal ridge was striking when contrasted to all other
areas.'' While it is reasonable to suggest that reduced food supply or
increased exposure to pesticides may have led to the decline of the
population in the Miami area, this link is only speculative because no
rigorous scientific studies or direct evidence exists. Timm and
Genoways (2004, p. 861) indicated that the extant, although small,
population of the bat in the Fakahatchee-Big Cypress area of southwest
Florida is located in one of the few areas of south Florida that has
not been sprayed with pesticides. Marks and Marks (2008a, p. 15)
contended that if the species' rarity and vulnerability are due to a
dependence on a limited food source or habitat, then the protection of
that food source or habitat is critical. Marks (2013, p. 2) also
recommended that natural habitats conducive to insect diversity be
protected and that any pesticides be used with caution. At this time,
however, it is not known what food source or habitat is most important
to the Florida bonneted bat.
In addition to pesticide exposure, mercury represents another
potential threat to the Florida bonneted bat that has not been
investigated. According to the National Atmospheric Deposition Program,
the mercury deposition rate in south Florida is among the highest in
the United States (http://nadp.isws.illinois.edu). The movement of
mercury through the aquatic system and into the terrestrial food web
through emergent invertebrates has been documented in other areas
(Cristol et al. 2008, p. 335; Konkler and Hammerschmidt 2012, p. 1659).
Assuming that a similar mechanism is occurring in south Florida coupled
with high mercury deposition rates, the consumption of such
invertebrates may constitute a pathway for the Florida bonneted bat to
be exposed to mercury.
[[Page 61036]]
Nam et al. (2012, pp. 1096-1098) documented mercury concentrations in
brain, liver, and fur in little brown bats near a mercury-contaminated
site in Virginia that were significantly greater than mercury
concentrations in the same tissues of little brown bats at a reference
site, indicating the potential for bats to be exposed to and accumulate
mercury near mercury-impacted systems. It is likely that the Florida
bonneted bat experiences some degree of mercury exposure when foraging
to a large extent above mercury-impacted water bodies. While no known
studies have attempted to evaluate the impact of mercury on bat
populations in south Florida, the neurotoxic effects of mercury on
mammals in general have been well characterized in the scientific
literature.
In 2012-2013, the Service worked with FDEP, UF, and other partners
to analyze available Florida bonneted bat fur samples for total mercury
in an attempt to assess mercury exposure. Nine fur samples were
obtained from frozen specimens collected from a bat house in North Fort
Myers in 2010, following a cold temperature event. An additional six
fur samples were obtained from available specimens from UF's Natural
History Museum. Three of the museum specimens were collected in Miami,
Florida, in the 1950s. The remaining three museum specimens were
collected from Babcock-Webb WMA in 1979. Results of the mercury
analysis revealed an overall mean of 24.69 milligram (mg) Hg (mercury)/
kg (kilogram) fur (FDEP 2013, pp. 1-7; A. Sowers, pers. comm. 2013). A
wide range of variability was observed between the samples as the
measured values ranged from 5.7 to 57 mg Hg/kg fur (FDEP 2013, pp. 1-7;
A. Sowers, pers. comm. 2013). For reference, Evers et al. (2012, p. 9)
provided mercury fur concentrations in 802 bats spread across 13
species from the northeastern United States. Based upon limited data,
the mean mercury concentrations of the Florida bonneted bat samples
(24.69 mg Hg/kg fur) were higher than the means reported for any of the
13 species (Evers et al. 2012, p. 9). None of the mean mercury
concentrations of the northeastern bat species exceeded 20 mg Hg/kg fur
(Evers et al. 2012, p. 9). It should be noted, however, that some of
the maximum mercury values reported by Evers et al. (2012, p. 9) did
exceed what was observed as maximum values in the Florida bonneted
bats. The results from the Florida bonneted bat analysis, compared with
those of other bat species across the northeast, suggest that exposure
to mercury is of concern. Further research is needed to determine if
such mercury exposure is having an adverse impact on the Florida
bonneted bat.
In summary, the effects of pesticides and contaminants on bat
populations in general have not been studied thoroughly. In the case of
the Florida bonneted bat, data concerning the effects of pesticides and
other contaminants are virtually nonexistent. Despite this lack of
data, the possibility exists for the Florida bonneted bat to be exposed
to a variety of compounds through multiple routes of exposure.
Additionally, areas with intensive pesticide activity may not support
an adequate food base for the species. Further study is required to
more fully assess the risk that pesticides and contaminants pose to the
Florida bonneted bat.
Ecological Light Pollution
Ecological light pollution is described as artificial light that
alters the natural patterns of light and dark in ecosystems (Longcore
and Rich 2004, p. 191). It includes ``direct glare, chronically
increased illumination, and temporary, unexpected fluctuations in
lighting,'' and many sources (e.g., streetlights, lighted buildings and
towers, sky glow) contribute to the phenomenon (Longcore and Rich 2004,
pp. 191-192). Depending upon scale and extent, ecological light
pollution can have demonstrable effects on behavioral and population
ecology of organisms, by disrupting orientation (or causing
disorientation), affecting movements (attraction or repulsion),
altering reproductive behaviors, and influencing communication
(Longcore and Rich 2004, pp. 193-195). Behaviors exhibited by
individuals in response to artificial lighting can affect community
interactions (e.g., competition and predation), and cumulative effects
have the potential to disrupt key ecosystem functions (Longcore and
Rich 2004, pp. 195-196).
The effects of artificial lighting on bats and their prey have been
partially studied. A wide array of insects have been found to be
attracted to lights (Frank 1988, pp. 63-93; Eisenbeis and Hassel 2000,
Kolligs 2000 as cited in Longcore and Rich 2004, p. 194). For example,
Frank (1988, pp. 63-93) examined the impact of outdoor lighting on
moths and found that it disturbs many necessary functions and may
affect some moth populations. Although the primary prey items for the
Florida bonneted bat are not known, it is possible that artificial
lighting may be affecting insect abundance or availability and prey
base in some locations.
Some species of bats are attracted to artificial lights to exploit
accumulations of insects that congregate at light sources (Griffin
1958; Bell 1980; Belwood and Fullard 1984; Haffner and Stutz 1985/86;
Baagee 1986; Schnitzler et al. 1987; Barak and Yom-Tov 1989 as cited in
Rydell 1991, p. 206; Frank 1988, pp. 63, 76). In one study examining
seasonal use of illuminated areas in Sweden, Rydell (1991, p. 206)
found significant concentrations of foraging northern bats (Eptesicus
nilssoni) only in villages illuminated by streetlights, supporting the
hypothesis that northern bats were attracted to the villages by lights
and not houses. Artificial lights appeared to provide local patches of
food for some bat species during periods that may be critical for
survival (Rydell 1991, pp. 203-207). In another study, Rydell (1992,
pp. 744-750) examined the exploitation of insects around streetlamps by
bats in Sweden and found that only the fast-flying species that use
long-range echolocation systems regularly foraged around streetlamps,
but others did not. Longcore and Rich (2004, p. 195) suggested that the
increased food concentration at artificial light sources may be a
positive effect for those species that can exploit such sources, but it
also could result in altered community structure.
The Florida bonneted bat's behavioral response to ecological light
pollution has not been examined, and effects are not known. The
species' fast-flight and long range flight capabilities may make it
more able to exploit insects congregated at artificial light sources or
more susceptible to risks associated with such responses (e.g.,
increased predation or harm from humans). Alternatively, artificial
lighting may not be influencing the species' foraging or other
behaviors. Research on the effects of artificial lighting on the
Florida bonneted bat and its prey would be beneficial.
Effects of Small Population Size, Isolation, and Other Factors
The Florida bonneted bat is vulnerable to extinction due to its
small population size, restricted range, few occupied areas, low
fecundity, and relative isolation. The Florida bonneted bat only occurs
in south Florida and only in limited numbers (Timm and Genoways 2004,
pp. 861-862; Marks and Marks 2008a, pp. 11, 15; 2008b, p. 4; 2012, pp.
12-15). Based on the small number of locations where calls were
recorded, the low numbers of calls recorded at each location, and the
fact
[[Page 61037]]
that the species forms small colonies, Marks and Marks (2008a, p. 15)
stated that it is possible that the entire population of Florida
bonneted bats may number less than a few hundred individuals. Other
experts suggested the population may be ``in the hundreds or low
thousands'' (FWC 2011b, p. 3). Due to its small population size and
restricted range, the species is considered to be one of the ``most
critically endangered'' mammals in North America (Timm and Genoways
2004, p. 861). In general, species with restricted ranges are often
characterized by small population sizes and high habitat specialization
and are, therefore, more vulnerable to stochastic, demographic, and
environmental processes (Lande et al. 2003 as cited in Lee and Jetz
2011, p. 1333).
In a vulnerability assessment, the FWC's biological status review
team determined that the species met criteria or listing measures for
geographic range, population size and trend, and population size and
restricted area (Gore et al. 2010, pp. 1-2). For geographic range, the
review team estimated that the species occurs in a combined area of
roughly 17,632 km\2\ (6,808 mi\2\), well below the criterion of <20,000
km\2\ (7,722 mi\2\). The review team also inferred a severely
fragmented range, with three subpopulations, all of which occur in
coastal locations susceptible to hurricanes and other losses in habitat
(see Climate Change and Sea Level Rise and Land Use Changes and Human
Population Growth, above). The review team also inferred continuing
decline in both extent of occurrence and area, extent, or quality of
habitat. For population size and trend, the review team estimated <100
individuals known in roosts, with an assumed total population of mature
individuals being well below the criterion of fewer than 10,000 mature
individuals. Similarly, for population size and restricted area, the
review team estimated <100 individuals of all ages known in roost
counts, inferring a total population to number fewer than 1,000 mature
individuals, and three subpopulations were located in at-risk coastal
zones.
Slow reproduction and low fecundity are also serious concerns
because this species produces only one young at a time and roosts
singly or in small groups (FBC 2005, p. 1; Timm and Arroyo-Cabrales
2008, p. 1). Assuming a lifespan of 10 to 20 years for bats of this
size (Wilkinson and South 2002, pp. 124-131), the average generation
time is estimated to be 5 to 10 years (Gore et al. 2010, p. 7). The
small numbers within localized areas may also make the Florida bonneted
bat vulnerable to extinction due to genetic drift (loss of unique genes
through time), inbreeding depression (reduced fitness or survival due
to low genetic diversity), extreme weather events (e.g., hurricanes),
and random or chance changes to the environment (Lande 1988, pp. 1455-
1459; Smith 1990, pp. 310-321) that can significantly impact its
habitat (see Environmental Stochasticity, below). Information on the
extent of genetic diversity in historical or current populations is
lacking.
In general, isolation, whether caused by geographic distance,
ecological factors, or reproductive strategy, will likely prevent the
influx of new genetic material and can result in low diversity, which
may impact viability and fecundity (Chesser 1983, pp. 66-77). Distance
between subpopulations or colonies, the small sizes of colonies, and
the general low number of bats may make recolonization unlikely if any
site is extirpated. Isolation of habitat can prevent recolonization
from other sites and potentially result in extinction. The probability
of extinction increases with decreasing habitat availability (Pimm et
al. 1988, pp. 758-762, 776; Noss and Cooperrider 1994, pp. 162-165;
Thomas 1994, pp. 373-378; Kale 1996, pp. 7-11). Although changes in the
environment may cause populations to fluctuate naturally, small and
low-density populations are more likely to fluctuate below a minimum
viable population (i.e., the minimum or threshold number of individuals
needed in a population to persist in a viable state for a given
interval) (Shaffer 1981, pp. 131-134; Shaffer and Samson 1985, pp. 146-
151; Gilpin and Soul[eacute] 1986, pp. 19-34). If populations become
fragmented, genetic diversity will be lost as smaller populations
become more isolated (Rossiter et al. 2000, pp. 1131-1135).
Fragmentation and aspects of the species' natural history (e.g.,
reliance on availability of suitable roost sites, constant supply of
insects) can contribute to and exacerbate other threats facing the
species.
Overall, the Florida bonneted bat is vulnerable to a wide array of
factors, including apparent small population size, restricted range,
few occurrences, low fecundity, and relative isolation. These threats
are significant and expected to continue or possibly increase.
Environmental Stochasticity
Natural events such as severe hurricanes may cause the loss of old
trees with roosting cavities (Timm and Genoways 2004, p. 861). In
August 1992, Hurricane Andrew, a category 5 hurricane, struck southern
Miami-Dade County with sustained surface windspeeds of more than 145
mph and gusts exceeding 175 mph (Timm and Genoways 2004, p. 861). The
winds destroyed the majority of older trees and snags within several
kilometers of the coast that were potentially available as roost trees
(Timm and Genoways 2004, p. 861; W. Kern, Jr., in litt. 2012). Timm and
Genoways (2004, p. 861) indicated that habitat loss from development
(see Factor A), increased use of pesticides, and Hurricane Andrew may
have had a significant impact on an already small population of the
Florida bonneted bat. For example, historical hurricane damage in the
Miami area eliminated all of the large pine snags in one study area,
leaving less than half a dozen large snags within a 526-ha (1,300-ac)
area (F. Ridgley, pers. comm. 2013b).
Several less intense hurricanes have impacted both coasts of
Florida during the past decade. Acoustical surveys conducted in south
Florida prior to the hurricane season of 2004 (from 1997 through 2003)
were compared with results after the hurricanes (Marks and Marks 2008a,
pp. 12, D1-D6, E1-E26). The limited number of locations and low number
of recorded calls suggested that the species was rare before the 2004
storm season and that the population remained low afterward (Marks and
Marks 2008a, pp. 12-15). Prior to the 2004 hurricane season, calls were
recorded at 4 of 10 locations; after the hurricane season, calls were
recorded at 9 of 44 locations (Marks and Marks 2008a, pp. 12-15).
Actions taken by a private landowner to reinforce bat houses prior to
Hurricane Charlie in 2004, and Hurricane Wilma in 2005, likely
prevented the only known extant roost site (at that time) from being
destroyed; these storms caused significant damage to both trees and
other property on the site (S. Trokey, pers. comm. 2008c).
Major impacts of intense storms may include mortality during the
storm, exposure to predation immediately following the storm, loss of
natural or artificial roost sites, and impacts on foraging areas and
insect abundance (Marks and Marks 2008a, pp. 7-9; W. Kern, Jr. in litt.
2012; R. Timm, in litt. 2012). In general, bats could be blown into
stationary objects or impacted by flying debris, resulting in injury or
mortality (Marks and Marks 2008a, p. 7). Trees with cavities can be
snapped at their weakest point, which for the Florida bonneted bat may
have the most severe impact since the species uses cavities (Marks and
Marks 2008a, p. 8); competition for available cavities in south Florida
is intense (Belwood 1992, p. 220), and suitable roosting sites in
[[Page 61038]]
general are often limiting factors (Humphrey 1975, pp. 341-343).
Displaced bats may be found on the ground or other unsuitable locations
and exposed to natural predators, domestic pets, and humans (Marks and
Marks 2008a, p. 8). As pregnant females have been found in June through
September, hurricanes in Florida can occur at critical life-history
stages--when females are pregnant or rearing young--possibly resulting
in losses of pregnant females, newborns, or juvenile pups (Marks and
Marks 2008a, pp. 7-9). Because the entire population may be less than a
few hundred individuals (Marks and Marks 2008a, p. 15; 2012, pp. 12-
15), the Florida bonneted bat may not be able to withstand losses from
intense storms or storms at a critical life-history stage.
Alternatively, less intense hurricanes or mild, isolated storms may
create roosting opportunities, if tree snags (dead trees) are left in
place.
According to the Florida Climate Center, Florida is by far the most
vulnerable State in the United States to hurricanes and tropical storms
(http://climatecenter.fsu.edu/topics/tropical-weather). Based on data
gathered from 1856 to 2008, Klotzbach and Gray (2009, p. 28) calculated
the climatological and current-year probabilities for each State being
impacted by a hurricane and major hurricane. Of the coastal States
analyzed, Florida had the highest climatological probabilities for
hurricanes and major hurricanes, with a 51 percent probability of a
hurricane and a 21 percent probability of a major hurricane over a 152-
year timespan. Of the States analyzed, Florida also had the highest
current-year probabilities, with a 45 percent probability of a
hurricane and an 18 percent probability of a major hurricane (Klotzbach
and Gray 2009, p. 28). Based upon data from the period 1886-1998,
Neumann et al. (1999, pp. 29-30) also found that the number of tropical
cyclones within south Florida is high; analyses suggested that areas
within the species' range (e.g., Fort Myers, Miami) are expected to
experience more than 50 occurrences (tropical cyclones) per 100 years.
In addition, the analyses suggested that the incidence of hurricanes in
south Florida was roughly 30 per 100 years, higher than any other area
except for North Carolina (Neumann et al. 1999, pp. 29-30). The number
of major hurricanes (roughly 14 per 100 years) was higher than any
other area examined (Neumann et al. 1999, p. 30).
Studies suggest that the frequency of high-severity hurricanes in
the Atlantic will become more frequent as climate warms (Elsner et al.
2008, pp. 92-95; Bender et al. 2010, pp. 454-458; Grinsted et al. 2012,
pp. 19601-19605). One model projects a doubling of frequency of
category 4 and 5 storms by the end of the 21st century with a decrease
in the overall frequency of tropical cyclones (Bender et al. 2010, pp.
454-458). In another study that examined records since 1923, warm years
in general were more active in all cyclone size ranges than cold years,
and a significant trend in the frequency of large surge events was
detected (Grinsted et al. 2012, pp. 19601-19605). Increases in
hurricane-generated wave heights have also been detected along the
Atlantic coast (Komar and Allan 2008, pp. 479-488).
If hurricanes and tropical storms increase in severity, frequency,
or distribution, vulnerable, tropical, tree-roosting bat species may be
heavily impacted (Gannon and Willig 2009, pp. 281-301). Given the
Florida bonneted bat's tree-roosting habits, apparent low abundance,
few isolated colonies, and use of coastal areas, the species is at risk
from hurricanes, storms, or other extreme weather. Depending on the
location and intensity, it is possible that the majority of Florida
bonneted bats could be killed in a fairly broad area during a single,
large, high-intensity hurricane (R. Timm, in litt. 2012). More frequent
and intense storms, increased storm surges, and coastal flooding can
impact Florida bonneted bats and roosting and foraging habitat. Due to
the bat's overall vulnerability, intense hurricanes are a significant
threat, which is expected to continue or increase in the future.
Other processes to be affected by climate change include
temperatures, rainfall (amount, seasonal timing, and distribution), and
storms (frequency and intensity). Temperatures are projected to rise
approximately 2 [deg]C to 5 [deg]C (3.6[emsp14][deg]F to
9[emsp14][deg]F) for North America by the end of this century (IPCC
2007, pp. 7-9, 13). In addition to climate change, weather variables
are extremely influenced by other natural cycles, such as El
Ni[ntilde]o Southern Oscillation with a frequency of every 4 to 7
years, solar cycle (every 11 years), and the Atlantic Multi-decadal
Oscillation. All of these cycles influence changes in Floridian
weather. The exact severity, direction, and distribution of all of
these changes at the regional level are difficult to project.
This species is also vulnerable to prolonged extreme cold weather
events. Air temperatures dropped to below freezing and reached a low of
-2.0 [deg]C (28[emsp14][deg]F) in ENP on January 11, 2010; air
temperatures at Royal Palm for the first 2 weeks of January marked the
coldest period recorded over the previous 10 years (Hallac et al. 2010,
p. 1). The effects of this severe and prolonged cold event on the
Florida bonneted bats or other bats in Florida are not known, but some
mortality was observed. At least 8 Florida bonneted bats were lost from
the North Fort Myers colony during the event, before 12 remaining bats
were brought into captivity, warmed, and fed (S. Trokey, pers. comm.
2010a). Those rescued were emaciated and in poor condition. Initially,
only 9 individuals appeared to survive after this event, although 10
individuals were still alive at this site in April 2010 (S. Trokey,
pers. comm. 2010a-c). Approximately 30 Brazilian free-tailed bats were
found dead below a bat house in Everglades City during this event (R.
Arwood, pers. comm. 2010). Overall, approximately 100 Brazilian free-
tailed bats using bat houses were found dead following this severe cold
event (C. Marks, pers. comm. 2011). South Florida again experienced
cold temperatures in December 2010. Temperatures in December 2010 were
among the coldest on record within ENP (J. Sadle, NPS, pers. comm.
2011). In the short term, the severe and prolonged cold events in south
Florida resulted in mortality of at least several adult Florida
bonneted bats at one observed site (S. Trokey, pers. comm. 2010a).
However, it is not known if the species persisted at all sites
previously documented following the prolonged and repeated cold
temperatures in 2010. Overall, the long-term effects of prolonged and
repeated cold events on the species are not known.
Molossids, the family of bats which includes the Florida bonneted
bat, appear to be an intermediate between tropical and temperate zone
bat families (Arlettaz et al. 2000, pp. 1004-1014). Members of this
family that inhabit the warmer temperate and subtropical zones incur
much higher energetic costs for thermoregulation during cold weather
events than those inhabiting northern regions (Arlettaz et al. 2000,
pp. 1004-1014). At such temperatures, bats are likely unable to find
food and cannot re-warm themselves. Such a stochastic, but potentially
severe, event poses a significant threat to the entire population.
Impacts of past cold weather events are evident, but the effect on all
colonies is not known. Additional extreme weather events are
anticipated in the future, and such extremes can have disastrous
impacts on small populations of mammals (R. Timm, pers. comm. 2012).
[[Page 61039]]
Aspects of the Species' Life History and Climate Change Implications
For bats in general, climate changes can affect food availability,
timing of hibernation, frequency of torpor, rate of energy expenditure,
reproduction, and development rate (Sherwin et al. 2012, pp. 1-18).
Although increased temperatures may lead to benefits (e.g., increased
food supply, faster development, range expansion), other negative
outcomes may also occur (e.g., extreme weather, reduced water
availability, spread of disease) (Sherwin et al. 2012, p. 14). Food
abundance is a fundamental factor influencing bat activity (Wang et al.
2010, pp. 315-323). Insectivorous bats are dependent upon ectothermic
(cold-blooded) prey, whose activity is affected by climate conditions
(Burles et al. 2009, pp. 132-138). Aerial-hawking species such as the
Florida bonneted bat are likely highly sensitive to climatic changes
due to their dependence on a food supply that is highly variable in
both time and space (Sherwin et al. 2012, p. 3).
In assessing implications of climate change, Sherwin et al. (2012,
p. 4) identified two risk factors directly related to foraging: (1)
Bats inhabiting water-stressed regions, and (2) aerial-hawking species,
which are reliant on spatially variable food sources. Bats generally
have higher rates of evaporative water loss than other similarly sized
terrestrial mammals and birds (Herreid and Schmidt-Nielsen 1966;
Studier 1970 as cited in Chruszcz and Barclay 2002, p. 24; Webb et al.
1995, p. 270). Due to their high surface area to volume ratios and
large, naked flight membranes (wings), the potential for loss of
evaporative water is generally high (Webb et al. 1995, pp. 269-278).
Travelling farther to access water and food entails more energy
expenditure and may affect reproductive success (Sherwin et al. 2012,
p. 4). Considering foraging risk alone, the Florida bonneted bat may be
especially susceptible to climate changes since it is an insectivorous,
aerial-hawking species largely restricted to south and southwest
Florida, a region expected to become water-stressed in the future (see
Factor A, above).
Summary of Factor E
Based on our analysis of the best available information, we have
identified a wide array of natural and manmade factors affecting the
continued existence of the Florida bonneted bat. Inadvertent or
purposeful impacts by humans caused by intolerance or lack of awareness
(e.g., removal, landscaping activities, and bridge maintenance) can
lead to mortality or disturbances to maternity colonies. The Florida
bonneted bat's ability to adapt well to manmade structures has likely
been a factor in its decline because the bat tends to inhabit
structures that place it at risk from inadvertent or purposeful harm by
humans. Competition for tree cavities from native and nonnative
wildlife is a potential threat. Proposed wind energy facilities in the
species' habitat can cause mortalities, and this threat may increase as
the demands for such facilities increase. The species may be exposed to
a variety of chemical compounds through multiple routes of exposure,
and intensive pesticide use may alter insect prey availability.
Ecological light pollution may also be a potential threat. Small
population size, restricted range, low fecundity, and few and isolated
colonies are serious ongoing threats. Catastrophic and stochastic
events are of significant concern. All occupied areas are at risk due
to hurricanes, which can cause direct mortality, loss of roost sites,
and other impacts. More frequent intense hurricanes may be anticipated
due to climate change. Extreme cold weather events can also have severe
impacts on the population and increase risks from other threats by
extirpating colonies or further reducing colony sizes. Collectively,
many of these threats have operated in the past, are impacting the
species now, and will continue to impact the Florida bonneted bat in
the future.
Determination of Status
We have carefully assessed the best scientific and commercial
information available regarding the past, present, and future threats
to the Florida bonneted bat. The species occurs in limited numbers in a
restricted range in south Florida. Habitat loss, degradation, and
modification from human population growth and associated development
and agriculture have impacted the Florida bonneted bat and are expected
to further curtail its limited range (see Factor A). Environmental
effects from climate change, including sea level rise and coastal
squeeze, are predicted to become severe in the future, resulting in
additional habitat losses that are expected to place the species at
greater risk (see Factor A).
The Florida bonneted bat also faces threats from a wide array of
natural and manmade factors (see Factor E). Effects of small population
size, restricted range, few colonies, slow reproduction, low fecundity,
and relative isolation contribute to the species' vulnerability. Other
aspects of the species' natural history (e.g., aerial-hawking foraging,
tree-roosting habits) and environmental stochasticity may also
contribute to its imperilment. Multiple anthropogenic factors are also
threats (e.g., impacts or intolerance by humans) or potential threats
(e.g., wind energy projects, ecological light pollution) of varying
severity. As an insectivore, the species is also likely exposed to a
variety of pesticides and contaminants through multiple routes of
exposure; pesticides may also affect its prey base. Given its
vulnerability, disease and predation (see Factor C) have the potential
to impact the species. Finally, existing regulatory mechanisms (see
Factor D), due to a variety of constraints, do not provide adequate
protection for the species. Overall, impacts from increasing threats,
operating singly or in combination, place the species at risk of
extinction.
Section 3 of the Act defines an endangered species as ``any species
which is in danger of extinction throughout all or a significant
portion of its range'' and a threatened species as ``any species which
is likely to become an endangered species within the foreseeable future
throughout all or a significant portion of its range.'' By all
indications, the species occurs only in limited numbers within a
restricted range and faces considerable and immediate threats, which
place it at risk of extinction. Aspects of the species' natural history
may also contribute to and exacerbate threats and increase its
vulnerability to extinction. Since immediate and ongoing significant
threats to the Florida bonneted bat extend throughout its entire range,
we have determined that the species is currently in danger of
extinction throughout all of its range. Because threats extend
throughout the entire range, it is unnecessary to determine if the
Florida bonneted bat is in danger of extinction throughout a
significant portion of its range. Therefore, on the basis of the best
available scientific and commercial information, we have determined
that the Florida bonneted bat meets the definition of an endangered
species under the Act. In other words, we find that a threatened
species status is not appropriate for the Florida bonneted bat because
of the severity and immediacy of the threats, the restricted range of
the species, and its apparent small population size. Consequently, we
are listing the Florida bonneted bat as an endangered species
throughout its entire range in accordance with sections 3(6) and
4(a)(1) of the Act.
[[Page 61040]]
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened species under the Act include recognition, recovery actions,
requirements for Federal protection, and prohibitions against certain
practices. Recognition through listing results in public awareness and
conservation by Federal, State, Tribal, and local agencies; private
organizations; and individuals. The Act encourages cooperation with the
States and requires that recovery actions be carried out for all listed
species. The protection required by Federal agencies and the
prohibitions against certain activities are discussed, in part, below.
The primary purpose of the Act is the conservation of endangered
and threatened species and the ecosystems upon which they depend. The
ultimate goal of such conservation efforts is the recovery of these
listed species, so that they no longer need the protective measures of
the Act. Subsection 4(f) of the Act requires the Service to develop and
implement recovery plans for the conservation of endangered and
threatened species. The recovery planning process involves the
identification of actions that are necessary to halt or reverse the
species' decline by addressing the threats to its survival and
recovery. The goal of this process is to restore listed species to a
point where they are secure, self-sustaining, and functioning
components of their ecosystems.
Recovery planning includes the development of a recovery outline
shortly after a species is listed, preparation of a draft and final
recovery plan, and revisions to the plan as significant new information
becomes available. The recovery outline guides the immediate
implementation of urgent recovery actions and describes the process to
be used to develop a recovery plan. The recovery plan identifies site-
specific management actions that will achieve recovery of the species,
measurable criteria that determine when a species may be downlisted or
delisted, and methods for monitoring recovery progress. Recovery plans
also establish a framework for agencies to coordinate their recovery
efforts and provide estimates of the cost of implementing recovery
tasks. Recovery teams (comprising species experts, Federal and State
agencies, nongovernmental organizations, and stakeholders) are often
established to develop recovery plans. When completed, the draft and
final recovery plans will be available on our Web site (http://www.fws.gov/endangered), or from our South Florida Ecological Services
Field Office (see FOR FURTHER INFORMATION CONTACT).
Implementation of recovery actions generally requires the
participation of a broad range of partners, including other Federal
agencies, States, Tribal, nongovernmental organizations, businesses,
and private landowners. Examples of recovery actions include habitat
restoration (e.g., restoration of native vegetation), research, captive
propagation and reintroduction, and outreach and education. The
recovery of many listed species cannot be accomplished solely on
Federal lands because their range may occur primarily or solely on non-
Federal lands. To achieve recovery of these species requires
cooperative conservation efforts on private, County, State, and Tribal
lands.
Once this species is listed (see DATES), funding for recovery
actions may be available from a variety of sources, including Federal
budgets, State programs, and cost share grants for non-Federal
landowners, the academic community, and nongovernmental organizations.
In addition, pursuant to section 6 of the Act, the State of Florida
will be eligible for Federal funds to implement management actions that
promote the protection and recovery of the Florida bonneted bat.
Information on our grant programs that are available to aid species
recovery can be found at: http://www.fws.gov/grants.
Section 7(a) of the Act requires Federal agencies to evaluate their
actions with respect to any species that is proposed or listed as an
endangered or threatened species and with respect to its critical
habitat, if any is designated. Regulations implementing this
interagency cooperation provision of the Act are codified at 50 CFR
part 402. Section 7(a)(4) of the Act requires Federal agencies to
confer with the Service on any action that is likely to jeopardize the
continued existence of a species proposed for listing or result in
destruction or adverse modification of proposed critical habitat. If a
species is listed subsequently, section 7(a)(2) of the Act requires
Federal agencies to ensure that activities they authorize, fund, or
carry out are not likely to jeopardize the continued existence of the
species or destroy or adversely modify its critical habitat. If a
Federal action may affect a listed species or its critical habitat, the
responsible Federal agency must enter into consultation with the
Service.
Federal agency actions within the species' habitat that may require
conference or consultation or both as described in the preceding
paragraph include, but are not limited to: management and any other
landscape-altering activities on Federal lands administered by the
Department of Defense, Fish and Wildlife Service, National Park
Service, and U.S. Forest Service; habitat restoration by the U.S.
Department of Agriculture, Natural Resources Conservation Service;
issuance of section 404 Clean Water Act (33 U.S.C. 1251 et seq.)
permits by the U.S. Army Corps of Engineers; permitting of construction
and management of gas pipeline, power line rights-of-way, and wind
energy facilities by the Federal Energy Regulatory Commission;
construction and maintenance of roads, highways, or bridges by the
Federal Highway Administration; and pesticide registration by the U.S.
Environmental Protection Agency.
The Act and its implementing regulations set forth a series of
general prohibitions and exceptions that apply to all endangered
wildlife. The prohibitions of section 9(a)(2) of the Act, codified at
50 CFR 17.21 for endangered wildlife, in part, make it illegal for any
person subject to the jurisdiction of the United States to take
(includes harass, harm, pursue, hunt, shoot, wound, kill, trap,
capture, or collect; or to attempt any of these), import, export, ship
in interstate commerce in the course of commercial activity, or sell or
offer for sale in interstate or foreign commerce any listed species.
Under the Lacey Act (18 U.S.C. 42-43; 16 U.S.C. 3371-3378), it is also
illegal to possess, sell, deliver, carry, transport, or ship any such
wildlife that has been taken illegally. Certain exceptions apply to
agents of the Service and State conservation agencies. The Florida
bonneted bat is listed by the State of Florida; therefore, certain
State laws also apply. Listing will also require Federal agencies to
avoid actions that might jeopardize the species (16 U.S.C. 1536(a)(2)),
and will provide opportunities for funding of conservation measures and
land acquisition that would not otherwise be available to them (16
U.S.C. 1534, 1535(d)).
We may issue permits to carry out otherwise prohibited activities
involving endangered and threatened wildlife species under certain
circumstances. Regulations governing permits are codified at 50 CFR
17.22 for endangered species, and at 17.32 for threatened species. With
regard to endangered wildlife, a permit must be issued for the
following purposes: for scientific purposes, to enhance the propagation
or survival of the species, and for incidental take in connection with
otherwise lawful activities.
[[Page 61041]]
It is our policy, as published in the Federal Register on July 1,
1994 (59 FR 34272), to identify to the maximum extent practicable at
the time a species is listed, those activities that would or would not
constitute a violation of section 9 of the Act. The intent of this
policy is to increase public awareness of the effect of a listing on
proposed and ongoing activities within the range of the federally
listed species.
We estimate that the following activities would be likely to result
in a violation of section 9 of the Act; however, possible violations
are not limited to these actions alone:
(1) Unauthorized possession, collecting, trapping, capturing,
killing, harassing, sale, delivery, or movement, including interstate
and foreign commerce, or harming or attempting any of these actions, of
Florida bonneted bats. Research activities where Florida bonneted bats
are handled, captured (e.g., netted, trapped), tagged, fitted with
radiotransmitters or other instrumentation, or collected will require
authorization pursuant to the Act.
(2) Incidental take of the Florida bonneted bat without
authorization pursuant to section 7 or section 10(a)(1)(B) of the Act.
(3) Sale or purchase of specimens of this taxon, except for
properly documented antique specimens of this taxon at least 100 years
old, as defined by section 10(h)(1) of the Act.
(4) Unauthorized destruction or alteration of Florida bonneted bat
occupied or potentially occupied habitat (which may include, but is not
limited to, unauthorized grading, leveling, plowing, mowing, burning,
clearing, lighting, or pesticide application) in ways that kills or
injures individuals by significantly impairing the species' essential
breeding, foraging, sheltering, or other essential life functions.
(5) Unauthorized release of biological control agents that attack
any life stage of this taxon.
(6) Unauthorized removal or destruction of cavity trees and other
natural structures being utilized as roosts by the Florida bonneted bat
that results in take of the species.
(7) Unauthorized removal or exclusion from buildings or artificial
structures being used as roost sites by the species that results in
take of the species.
(8) Unauthorized maintenance or repair of bridges or overpasses
that are being used as roost sites by the Florida bonneted bat that
results in take of the species.
(9) Unauthorized building and operation of wind energy facilities
within areas used by the Florida bonneted bat that results in take of
the species.
We will review other activities not identified above on a case-by-
case basis to determine whether they may be likely to result in a
violation of section 9 of the Act. We do not consider these lists to be
exhaustive, and we provide them as information to the public.
Questions regarding whether specific activities would constitute a
violation of section 9 of the Act should be directed to the Field
Supervisor of the Service's South Florida Ecological Services Field
Office (see FOR FURTHER INFORMATION CONTACT). Requests for copies of
the regulations concerning listed animals and general inquiries
regarding prohibitions and permits may be addressed to the U.S. Fish
and Wildlife Service, Endangered Species Permits, 1875 Century
Boulevard, Atlanta, GA 30345 (Phone 404-679-7313; Fax 404-679-7081).
Jeopardy Standard
Prior to and following listing, the Service applies an analytical
framework for jeopardy analyses that relies heavily on the importance
of core area populations to the survival and recovery of the species.
The section 7(a)(2) analysis is focused not only on these populations
but also on the habitat conditions necessary to support them.
The jeopardy analysis usually expresses the survival and recovery
needs of the species in a qualitative fashion without making
distinctions between what is necessary for survival and what is
necessary for recovery. Generally, if a proposed Federal action is
incompatible with the viability of the affected core area
populations(s), inclusive of associated habitat conditions, a jeopardy
finding is considered to be warranted, because of the relationship of
each core area population to the survival and recovery of the species
as a whole.
Critical Habitat
Background
Critical habitat is defined in section 3 of the Act as:
(1) The specific areas within the geographical area occupied by the
species, at the time it is listed in accordance with the Act, on which
are found those physical or biological features
(a) Essential to the conservation of the species and
(b) Which may require special management considerations or
protection; and
(2) Specific areas outside the geographical area occupied by the
species at the time it is listed, upon a determination that such areas
are essential for the conservation of the species.
Conservation, as defined under section 3 of the Act, means to use
and the use of all methods and procedures that are necessary to bring
an endangered or threatened species to the point at which the measures
provided pursuant to the Act are no longer necessary. Such methods and
procedures include, but are not limited to, all activities associated
with scientific resources management such as research, census, law
enforcement, habitat acquisition and maintenance, propagation, live
trapping, and transplantation, and, in the extraordinary case where
population pressures within a given ecosystem cannot be otherwise
relieved, may include regulated taking.
Critical habitat receives protection under section 7 of the Act
through the requirement that Federal agencies ensure, in consultation
with the Service, that any action they authorize, fund, or carry out is
not likely to result in the destruction or adverse modification of
critical habitat. The designation of critical habitat does not affect
land ownership or establish a refuge, wilderness, reserve, preserve, or
other conservation area. Such designation does not allow the government
or public to access private lands. Such designation does not require
implementation of restoration, recovery, or enhancement measures by
non-Federal landowners. Where a landowner requests Federal agency
funding or authorization for an action that may affect a listed species
or critical habitat, the consultation requirements of section 7(a)(2)
of the Act would apply, but even in the event of a destruction or
adverse modification finding, the obligation of the Federal action
agency and the landowner is not to restore or recover the species, but
to implement reasonable and prudent alternatives to avoid destruction
or adverse modification of critical habitat.
Section 4 of the Act requires that we designate critical habitat on
the basis of the best scientific data available. Further, our Policy on
Information Standards Under the Endangered Species Act (published in
the Federal Register on July 1, 1994 (59 FR 34271)), the Information
Quality Act (section 515 of the Treasury and General Government
Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658)),
and our associated Information Quality Guidelines provide criteria,
establish procedures, and provide guidance to ensure that our decisions
[[Page 61042]]
are based on the best scientific data available. They require our
biologists, to the extent consistent with the Act and with the use of
the best scientific data available, to use primary and original sources
of information as the basis for recommendations to designate critical
habitat.
When we are determining which areas should be designated as
critical habitat, our primary source of information is generally the
information developed during the listing process for the species.
Additional information sources may include the recovery plan for the
species, articles in peer-reviewed journals, conservation plans
developed by States and counties, scientific status surveys and
studies, biological assessments, other unpublished materials, or
experts' opinions or personal knowledge.
Critical Habitat Prudency
We found that designation of critical habitat for the Florida
bonneted bat is prudent. For further discussion, see the proposed
listing rule (77 FR 60749; October 4, 2012).
Critical Habitat Determinability
Our regulations (50 CFR 424.12(a)(2)) further state that critical
habitat is not determinable when one or both of the following
situations exist: (1) Information sufficient to perform the required
analysis of the impacts of the designation is lacking, or (2) the
biological needs of the species are not sufficiently well known to
permit identification of an area as critical habitat.
In accordance with sections 3(5)(A)(i) and 4(b)(1)(A) of the Act
and regulations at 50 CFR 424.12, in determining which areas to propose
as critical habitat, we must consider those physical and biological
features essential to the conservation of the species. These include,
but are not limited to:
(1) Space for individual and population growth and for normal
behavior;
(2) Food, water, air, light, minerals, or other nutritional or
physiological requirements;
(3) Cover or shelter;
(4) Sites for breeding, reproduction, and rearing (or development)
of offspring;
and
(5) Habitats that are protected from disturbance or are
representative of the historical, geographical, and ecological
distribution of a species.
We conducted an evaluation to find if the designation of critical
habitat for the Florida bonneted bat is determinable. Based on that
evaluation, we are currently unable to identify the physical and
biological features essential for the conservation of the Florida
bonneted bat because information on those features for this species
remains uncertain. The apparent poor viability of the species recorded
in recent years indicates that current conditions are not sufficient to
meet the basic biological requirements of the species in most areas of
its current range.
Species-specific ecological requirements (e.g., natural roost
sites, seasonal changes in roosting habitat, dietary needs, seasonal
changes in diet, prime foraging habitat) are currently being
researched. Population dynamics, such as species interactions and
community structure, population trends, and population size and age
class structure necessary to maintain long-term viability, have not
been fully determined. As we are unable to identify many physical and
biological features essential to the conservation of the Florida
bonneted bat, we are unable to identify areas that contain features
necessary for long-term viability. Therefore, we find that critical
habitat is not determinable at this time.
As one peer reviewer stated during the public comment period,
identifying home ranges and habitat affinities of the Florida bonneted
bat is imperative to determining the physical and biological features
essential to the conservation of the species. In order for designation
of critical habitat to be meaningful and effective, the extent of the
species' range and the species' roosting affinities should be defined
prior to designation. The Service continues to work with researchers,
other agencies, and stakeholders on filling large information gaps
regarding the species and its habitat needs and preferences. We
continue to fund research and study the habitat requirements of the bat
and we intend to publish a proposed critical habitat designation for
the Florida bonneted bat in a separate rule in the near future.
Required Determinations
National Environmental Policy Act (42 U.S.C. 4321 et seq.)
We have determined that environmental assessments and environmental
impact statements, as defined under the authority of the National
Environmental Policy Act, need not be prepared in connection with
listing a species as an endangered or threatened species under the Act.
We published a notice outlining our reasons for this determination in
the Federal Register on October 25, 1983 (48 FR 49244).
References Cited
A complete list of references cited in this rulemaking is available
on the Internet at http://www.regulations.gov and upon request from the
Field Supervisor, South Florida Ecological Services Field Office (see
FOR FURTHER INFORMATION CONTACT).
Authors
The primary authors of this rule are the staff members of the South
Florida Ecological Services Field Office.
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, Transportation.
Regulation Promulgation
Accordingly, we amend part 17, subchapter B of chapter I, title 50
of the Code of Federal Regulations, as follows:
PART 17--[AMENDED]
0
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 1531-1544; 4201-4245, unless
otherwise noted.
0
2. Amend Sec. 17.11(h) by adding an entry for ``Bat, Florida
bonneted'' to the List of Endangered and Threatened Wildlife in
alphabetical order under Mammals, to read as follows:
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
[[Page 61043]]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species Vertebrate
-------------------------------------------------------- population where Critical Special
Historic range endangered or Status When listed habitat rules
Common name Scientific name threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mammals
* * * * * * *
Bat, Florida bonneted............ Eumops floridanus... U.S.A. (FL)........ Entire............. E 822 NA NA
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * *
Dated: September 19, 2013.
Rowan W. Gould,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2013-23401 Filed 10-1-13; 8:45 am]
BILLING CODE 4310-55-P