Daily Rules, Proposed Rules, and Notices of the Federal Government
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This document consists of: (1) A proposed rule to list the Florida bonneted bat as an endangered species; (2) a finding that designation of critical habitat for the species is prudent; and (3) a finding that critical habitat is not determinable at this time because the biological needs of the species are not sufficiently well known to permit identification of areas as critical habitat.
We intend that any final action resulting from this proposed rule will be based on the best scientific and commercial data available and be as accurate and as effective as possible. Therefore, we request comments or information from the public, other concerned governmental agencies, Native American tribes, the scientific community, industry, or any other interested parties concerning this proposed rule. We particularly seek comments concerning:
(1) Additional information concerning the historical and current status, range, distribution, and population size of this species, including the locations of any additional populations or colonies of this species.
(2) Any information on the biological or ecological requirements of the species, especially life history information and habitat needs (e.g., preferred roosting and foraging habitat, nightly and seasonal movements, dispersal capabilities, diet, and seasonal changes in diet), and ongoing conservation measures for the species and its habitat.
(3) Biological, commercial trade, or other relevant data concerning any threats (or lack thereof) to this species and regulations that may be addressing those threats.
(4) Current or planned land use activities in the areas occupied by the species and possible impacts of these activities on this species.
(5) Additional information regarding the threats under the five listing 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.
(6) What physical or biological features (e.g., space, food, water, cover or shelter, sites for breeding and rearing of offspring, protected habitats) are essential to the conservation of the species.
(7) The reasons why we should or should not designate habitat as “critical habitat” under section 4 of the Act (16 U.S.C. 1531
(8) Specific information on:
(a) The amount and distribution of habitat for the Florida bonneted bat;
(b) What areas, which are occupied at the time of listing (or are currently occupied) contain features essential to the conservation of the species, should be included in a designation and why;
(c) Special management considerations or protection that may be needed in critical habitat areas, including managing for the potential effects of climate change; and
(d) What areas not occupied at the time of listing are essential for the conservation of the species and why.
(9) Information on the projected and reasonably likely impacts of climate
Please note that submissions merely stating support for or opposition to the action under consideration without providing supporting information, although noted, will not be considered in making a determination, as section 4(b)(1)(A) of the Act directs that determinations as to whether any species is a threatened or endangered species must be made “solely on the basis of the best scientific and commercial data available.”
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This document consists of: (1) A proposed rule to list the Florida bonneted bat (
We use many acronyms and abbreviations throughout this proposed rule. To assist the reader, we provide a list of these here for easy reference:
The Florida bonneted bat (
On September 18, 1985, we published a Review of Vertebrate Wildlife for Listing as Endangered or Threatened Species (50 FR 37958), which included the Florida mastiff bat as a category 2 candidate species for possible future listing as an endangered or threatened species. Category 2 candidates were those taxa for which information contained in our files indicated that listing may be appropriate, but for which additional data were needed to support a listing proposal. In a January 6, 1989, Animal Notice of Review (54 FR 554), the Florida mastiff bat continued as a category 2 candidate. On November 21, 1991, the Florida mastiff bat was upgraded from a category 2 to a category 1 species in an Animal Candidate Review for Listing as Endangered or Threatened Species (56 FR 58804), characterized as having a declining trend (indicating decreasing numbers or increasing threats or both). It remained a category 1 candidate (declining trend) in the 1994 review (59 FR 58982). In 1996, the Florida mastiff bat was removed from the candidate list (61 FR 7596) because the taxon was deemed to be more abundant or widespread than previously believed or not subject to any identifiable threat.
On November 9, 2009, we recognized the Florida bonneted bat (
On January 29, 2010, we received a petition from Wild South to list the Florida bonneted bat as an endangered species and to designate critical habitat pursuant to the Act (O'Malley 2010). The petition heavily relied upon the Service's 2009 species assessment, but did not provide any new substantial
On May 10, 2011, the Service announced a work plan to restore biological priorities and certainty to the Service's listing process. As part of an agreement with one of the agency's most frequent plaintiffs, the Service filed a work plan with the U.S. District Court for the District of Columbia. The work plan will enable the agency to, over a period of 6 years, systematically review and address the needs of more than 250 species listed within the 2010 Candidate Notice of Review, including the Florida bonneted bat, to determine if this species should be added to the Federal Lists of Endangered and Threatened Wildlife and Plants. This work plan will enable the Service to again prioritize its workload based on the needs of candidate species, while also providing State wildlife agencies, stakeholders, and other partners clarity and certainty about when listing determinations will be made. On July 12, 2011, the Service reached an agreement with a frequent plaintiff group and further strengthened the work plan, which will allow the agency to focus its resources on the species most in need of protection under the Act. These agreements were approved on September 9, 2011. The timing of this proposed listing is, in part, therefore, an outcome of the work plan.
The Service's decision to propose listing of the Florida bonneted bat resulted from our careful review of the status of the species and the threats it faces.
The Florida bonneted bat is a member of the Molossidae (free-tailed bats) family within the order Chiroptera. The species is approximately 130 to 165 millimeters (mm) (5.1 to 6.5 inches [in]) in length (Timm and Genoways 2004, p. 857) and the largest bat in Florida (Owre 1978, p. 43; Belwood 1992, p. 216; Florida Bat Conservancy [FBC] 2005, p. 1). The length of the tail ranges from 46 to 57 mm (1.8 to 2.2 in), hind foot 11 to 15 mm (0.4 to 0.6 in), ear 20 to 30 mm (0.8 to 1.2 in), and forearm 60.8 to 66.0 mm (2.39 to 2.60 in) (Timm and Genoways 2004, p. 857). Masses average 39.7 grams (g) (1.4 ounces [oz]) and range from 30.2 to 46.6 grams (1.1 to 1.6 oz) (Owre 1978, p. 43; Belwood 1981, p. 412; Belwood 1992, p. 216; Timm and Genoways 2004, p. 857). A pregnant female with a single fetus weighed 55.4 g (2.0 oz) (Belwood 1981, p. 412). Males and females are not significantly different in size (Timm and Genoways 2004, p. 857). Timm and Genoways (2004, p. 857) found no pattern of size-related geographic variation in this species.
Members of the genus
Wings of the members of the genus
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; color varies from black to brown to brownish-gray or cinnamon brown with ventral pelage paler than dorsal (Owre 1978, p. 43; Belwood 1992, p. 216; Timm and Genoways 2004, p. 857). The basisphenoid pits (paired depressions in the basisphenoid bone) of the skull are ovoid (egg-shaped) and moderately deep (Timm and Genoways 2004, p. 857). The tail projects beyond the interfemoral membrane (skin that stretches between the legs) (Owre 1978, p. 43; Belwood 1992, p. 216).
Allen (1932, pp. 256-259) first described a new genus and species of Pleistocene free-tailed bat,
Timm and Genoways (2004, p. 852) reviewed and reassessed the taxonomic status of bats of the genus
The Florida bonneted bat (
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
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-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
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, 2012). After the 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 February 2012, there are 18 bats using two houses at this location (S. Trokey, pers. comm. 2012). 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), 42 individuals are using 4 separate roosts, consisting of 7 bat houses among 4 sites (J. Myers, pers. comm. 2012a, 2012b; Marks and Marks 2012, pp. 8, 12, A61). These sites each consist of two bat houses on a single pole, with the exception of one site, which has a pole containing only one house. The most recent counts from simultaneous observations at these sites, taken at emergence on April 19, 2012, documented the following: 35 Florida bonneted bats at 2 houses, 5 at 2 houses, 1 at 2 houses, and 1 at 1 house (J. Myers, pers. comm. 2012a; Marks and Marks 2012, pp. 12, 19, A61). 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.
The Florida bonneted bat is active year-round and does not have periods of hibernation or torpor. The species is not migratory, but there might have been seasonal shifts in roosting sites (Timm
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. Based upon limited information, Florida bonneted bats feed on flying insects of the following orders: Coleoptera (beetles), Diptera (true flies), and Hemiptera (true bugs) (Belwood 1981, p. 412; Belwood 1992, p. 220; FBC 2005, p. 1). 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). No other similar analyses have been performed, but 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. 2012; S. Snow, Everglades National Park (ENP), pers. comm. 2012). This species may prey upon larger insects, which may be less abundant than smaller prey items (S. Snow, pers. comm. 2012). Since the species can take flight from the ground like other
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
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
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
Recent information on foraging 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 meters (30 feet) 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 meters (100 feet); call sequences are analyzed using software that compares calls to a library of 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).
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 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).
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 suggests that the species uses a wide variety of habitats (see Table 1) (Marks and Marks 2008a, pp. 13-14; 2008b, pp. 2-5; 2008c, pp. 1-28; 2012, pp. 1-22; R. Arwood, Inside-Out Photography, Inc., pers. comm. 2008a, 2008b, 2012; Smith 2010, pp. 1-4; S. Snow, pers. comm. 2011, 2012).
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 (
Similar roosting habitats have been reported for
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, canals, etc. (see Table 1). Table 1 lists locations and habitat types where Florida bonneted bats were recorded or observed (2003 to present) (Marks and Marks 2008a, pp. 13-14; 2008b, pp. 2-5; 2008c, pp. 1-28; 2012, pp. 1-22; R. Arwood, pers. comm. 2008a, 2008b, 2012; Smith 2010, pp. 1-4; S. Snow, pers. comm. 2011, 2012; FNAI 2012, pp. 1-28). Additional details on key sites are provided below Table 1.
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,
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 call was recorded in 16 survey nights in 2007 (Marks and Marks 2008a, pp. 11, A12-A14). The call 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. 2012; 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. 2012) and available land use covers derived from a geographic information system also suggest that the species uses a wide array of habitats within BCNP.
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 without a roost site being known (Smith 2010, p. 1).
In 2000, the species was found 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 calls at this location (Marks and Marks 2008a, pp. 6, 11, 14). In 2007, the species had been recorded at a backcountry campsite (Watson's Place) within ENP, comprised of mixed hardwoods (S. Snow, pers. comm. 2012). In 2012, the species was found within mangroves and mixed hardwoods at another backcountry campsite (Darwin's Place) along the Wilderness Waterway (Ten Thousand Island area), approximately 4.8 kilometers (km) (3 miles) east-southeast of Watson's Place within ENP (Marks and Marks 2012, pp. 8, 17, A53, B35, B38; C. Marks, pers. comm. 2012; S. Snow, pers. comm. 2012). 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 found in various natural habitats elsewhere in ENP and vicinity (S. Snow, pers. comm. 2011, 2012; Marks and Marks 2012, pp. 8, 14). It was found in wetlands and pinelands at the junction of the main park road and road to Long Pine Key (S. Snow, pers. comm. 2011, 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 (S. Snow, pers. comm. 2012; Marks and Marks 2012, pp. 8, 14, 17, A59). In March 2012, one suspect (presumed, but not confirmed) call sequence was also recorded on SR 9336 in an area of rural residential and agricultural habitat in Miami-Dade County (S. Snow, pers. comm. 2012). 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. 2012).
In 2008, the Florida bonneted bat was found 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; the other was at Platt's Bluff boat ramp at a public park on the Kissimmee River (Marks and Marks 2008c, pp. 11, 17). However, despite numerous attempts, 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 its range (C. Marks, pers. comm. 2012a; Marks and Marks 2012, pp. 3, 5, 8, 10) (see
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 such structures are 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 and eradicated or excluded from dwellings (see
This species may also roost in rocky crevices and outcrops on the ground, based on the discovery of an adult for which the specimen tag says “found under rocks when bull-dozing 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,
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 in Miami-Dade County (C. Marks, pers. comm. 2011; Ridgley 2012, p. 1; Marks and Marks 2012, pp. 8, 14, 16, A26). 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 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 (Ridgley 2012, p. 1; Marks and Marks 2012, pp. 8, 14, 16, A26). Surrounding habitats include natural areas and horticulturally altered landscape, with a variety of manmade structures (Ridgley 2012, p. 1).
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. 2011, 2012; Marks and Marks 2012, pp. 8, 13-14, 17, A35, A37).
The Florida bonneted bat can use artificial structures (Marks and Marks 2008a, p. 8; Morse 2008, pp. 1-14; S. Trokey, pers. comm. 2012). In fact, all of the active known roosting sites for the species are bat houses (two at a private landowner's house; four at Babcock-Webb WMA).
The species occupies bat houses on private land in North Fort Myers, Lee County; until 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. 2012). The bat houses are located near a small pond, situated approximately 5 meters (17 feet) above the ground with a south by southwest orientation (S. Trokey, pers. comm. 2012). The relatively high height of the houses may allow the large bats to fall from the roosts before flying (S. Trokey, pers. comm. 2012).
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 meters (17 feet) above the ground with north and south orientations (J. Myers, pers. comm. 2012a; Marks and Marks 2012, pp. 12, 19, A61). 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).
In summary, relatively little is known of the species' habitat requirements. Based upon available data above, it appears that the species can use a wide array of habitat types (see Table 1 above). Available information on roosting sites is extremely limited and particularly problematic, since the availability of suitable roosts is an important, limiting factor for most bat species. Existing roost sites need to be identified so they can be preserved and protected (Marks and Marks 2008a, p. 15). Uncertainty regarding the location of natural and artificial roost sites may contribute to the species' vulnerability (see
Records indicating historical range are limited. Morgan (1991, p. 200) indicated that
Timm and Genoways (2004, p. 856) noted that
Most of the historical records and sightings for this species are several decades old from the cities of Coral Gables and Miami in extreme southeastern Florida, where the species was once believed to be common (Belwood 1992, pp. 216, 219; Timm and Genoways 2004, p. 857; Timm and Arroyo-Cabrales 2008, p. 1). G.T. Hubbell also reported a female with young from Fort Lauderdale in Broward County; all of his sightings of Florida bonneted bats were near human dwellings (Belwood 1992, p. 219). Prior to 1967, G.T. Hubbell regularly heard loud, distinctive calls at night as the bats foraged above buildings and he routinely obtained several individuals per year that were collected during the winter months from people's houses (Belwood 1992, pp. 216-217). Layne (1974, p. 389) stated, “This bat has the most restricted range of any Florida mammal, being only known from Miami, Coral Gables, and Coconut Grove, where it inhabits buildings in residential areas with lush vegetative growth” (Barbour, 1936; Schwartz 1952a; Jennings, 1958).
Other early literature also mentioned Fort Lauderdale as an area where the species occurred (Barbour and Davis 1969, p. 231; Belwood 1992, pp. 218-219). However, in their comprehensive review, none of the specimens examined by Timm and Genoways (2004, pp. 856-857, 864) were from
As part of a status survey, Robson (1989, pp. 8-9) examined available specimens from museum collections (University of Miami, Miami-Dade Community College, and Florida Museum of Natural History) dating from 1951-1989. Of the 21 specimens examined, 11 were from Coral Gables, 4 were from Miami, 3 were from North Miami, and 3 were from Punta Gorda (Robson 1989, p. 8). As part of the same study, Robson (1989, p. 9) investigated 44 reports of bats throughout southern Florida in 1989, but did not collect or observe the Florida bonneted bat. Another 25 sites were selected for acoustical sampling as part of this study. Records of bats from the selected sites were generally scant or nonexistent; only one record from Coral Gables was found (Robson 1989, p. 9). Despite considerable effort (1,724 stops during 86.2 hours), no additional evidence of the species was found in this study (Robson 1989, pp. 9, 15).
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, confined to south 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) Range-wide surveys conducted in 2006-2007, funded by the Service, to determine the status of the Florida bonneted bat following the 2004 hurricane season, and followup 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. 2012); (4) surveys conducted in 2011-2012 in ENP by NPS staff (S. Snow, pers. comm. 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); and (6) recordings taken from proposed wind energy facilities in Glades and Palm Beach Counties (C. Coberly, Merlin Environmental, pers. comm. 2012; C. Newman, Normaneau Associates, Inc, pers. comm. 2012). These survey efforts and results are described in more detail below.
Results of range-wide acoustical surveys in 2006-2007 documented presence in Charlotte, Lee, Collier, and Miami-Dade Counties (see Table 1; Marks and Marks 2008a, p. 11). As part of this study, all previous known locations for the Florida bonneted bat and other previously unsurveyed areas were surveyed to determine presence (Marks and Marks 2008a, p. 3). In total, 50 survey nights were conducted at select locations in south Florida with 48 areas surveyed (Marks and Marks 2008a, pp. 9-10; 2012, p. 5). Echolocation calls were recorded by researchers at six of the areas surveyed (Marks and Marks 2008a, p. 10). Although Broward County was previously considered part of the species' range (Barbour and Davis 1969, p. 231; Belwood 1992, pp. 218-219; Hipes
Following this study, Marks and Marks (2008a, p. 10) concluded that “based on the surveys conducted to date, the full extent of the Florida bonneted bat population exists within a very limited range extending from the Babcock Webb WMA through southwest Florida to south Miami and Homestead.” More detailed information regarding locations is provided above (see