Urban Roosts: Use of Buildings by Florida Bonneted Bats - Elysia N. Webb, Holly K. Ober, Elizabeth C. Braun de Torrez, Jeffery A. Gore, and ...
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Urban Roosts:
Use of Buildings by
Florida Bonneted Bats
Elysia N. Webb, Holly K. Ober,
Elizabeth C. Braun de Torrez,
Jeffery A. Gore, and Ricardo Zambrano
No. 42 Urban Naturalist 2021
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Cover Photograph: A Florida Bonneted Bat (Eumops floridanus) captured during this study. Dade County,
Florida. Photograph © Elysia Webb.
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2021 Urban Naturalist No. 42
2021 Urban Naturalist 42:1–11
E.N. Webb, H.K. Ober, E.C. Braun de Torrez, J.A. Gore, R. Zambrano
Urban Roosts: Use of Buildings by Florida Bonneted Bats
Elysia N. Webb1, Holly K. Ober1,*, Elizabeth C. Braun de Torrez1,2,
Jeffery A. Gore3, and Ricardo Zambrano4
Abstract - Florida Bonneted Bats, Eumops floridanus, were first documented in Miami, Florida,
USA, in the 1930s. We summarized reports of these bats in the greater Miami area throughout the
past 80 years and documented new roosts by radio-tracking bats captured in semi-natural areas.
Florida Bonneted Bats in Miami consistently roosted in buildings, in contrast to other portions of
the species’ range where they use trees and bat houses. Throughout the past 60 years, reports of
building use have been confined to a small (40 km2) portion of the city. Bats regularly selected
buildings with architectural similarities (Mediterranean Revival style; characterized by stucco
exteriors, open chimneys with integrated arch covers, and clay tile roofs). To ensure adequate con-
servation measures are taken to minimize harm to this federally endangered species in urban areas,
we outline four topics in need of additional research and suggest four topics that should be covered
through targeted educational campaigns.
Introduction
Eumops floridanus (Allen 1932) (Florida Bonneted Bat) is a federally endangered spe-
cies endemic to southern and central Florida, with a geographic distribution believed to be
among the smallest of all bat species in the New World (FWC 2011, Timm and Genoways
2004). The US Fish and Wildlife Service (USFWS) listed Florida Bonneted Bats as feder-
ally endangered in 2013, citing concerns about habitat loss, degradation, and modification
from human population growth as well as the species’ small population size, slow reproduc-
tion, low fecundity, and relative isolation (USFWS 2013). The ongoing loss and modifica-
tion of natural areas is of great concern to the future wellbeing of these bats, given the small
size of their geographic range and the likelihood of climate change causing coastal portions
of the current range to become unsuitable (USFWS 2013).
Location and characterization of structures used as roosts for the Florida Bonneted
Bats has been identified as a key research priority of both the USFWS (USFWS 2013)
and the Florida Fish and Wildlife Conservation Commission (FWC) (FWC 2013). Most
recent efforts to identify roosts have occurred in natural areas, where the species has
been documented using Pinus palustris Mill and Pinus elliottii Engelm, Roystonea spp.
(Royal Palm Trees), and Taxodium distichum (L.) Rich, as well as artificial structures,
including bat houses and a utility pole (Angell and Thompson 2015; Belwood 1992;
Braun de Torrez et al. 2016, 2020 unpubl. data; Timm and Genoways 2004; Webb 2017
unpubl. data). Although decades-old records indicate the species resided in buildings in
the greater Miami area (Barbour and Davis 1969, Gore et al. 2015, Owre 1978, Robson
et al. 1989, Timm and Genoways 2004), little effort has been made to characterize the
types of structures used by bats or changes in use over time as urbanization has intensi-
fied. Guidelines recently established by the USFWS to minimize potential negative im-
1
Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL 32611 USA.
2
Florida Fish and Wildlife Conservation Commission, Gainesville, FL 32601 USA. 3Florida Fish and
Wildlife Conservation Commission, Panama City, FL 32409 USA. 4Florida Fish and Wildlife Conserva-
tion Commission, West Palm Beach, FL 33412 USA. *Corresponding author: holly.ober@ufl.edu.
Manuscript Editor: Brooke Maslo
12021 Urban Naturalist No. 42
E.N. Webb, H.K. Ober, E.C. Braun de Torrez, J.A. Gore, R. Zambrano
pacts to existing habitat for these bats (Florida Bonneted Bat Consultation Guidelines,
available at https://www.fws.gov/verobeach/ListedSpeciesMammals.html) delineate
not only the region where the species is presumed to occur (the “Consultation Area”)
but also the urban development boundary (the “South Florida Urban Bat Area”), where
the species is suspected to rely largely on artificial structures as roosts (Fig. 1A). Given
that a substantial portion of their geographic range is undergoing urbanization, there
is an urgent need to better understand use of urban environments by this endangered
species.
Our objective was to increase understanding of Florida Bonneted Bat roost use in the
most intensely urbanized region within their geographic range. Specifically, we identified
locations where these bats roosted in the greater Miami area and evaluated how the location
and type of roost structures has changed over time. Because the current Florida Bonneted
Bat Consultation Guidelines do not include recommendations for urban environments, this
synthesis of data from the greater Miami area can provide insight that directly informs con-
servation and management recommendations for these bats in this region as well as other
urbanizing areas across the species range.
Figure 1. Maps showing (A) the location of Florida within the USA, the region designated by the US Fish and Wildlife
Service (USFWS) as the currently accepted geographic range for Florida Bonneted Bats, Eumops floridanus (“Consulta-
tion Area”), and the location of our study region, designated by USFWS as the “South Florida Urban Bat Area”; (B) the
location of 2017 Florida Bonneted Bat (FBB) capture attempts within the “South Florida Urban Bat Area” and historical
and recent records of buildings occupied by Florida Bonneted Bats and; and (C) the area of most intense use over time
by Florida Bonneted Bats in Coral Gables (Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus
DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community).
22021 Urban Naturalist No. 42
E.N. Webb, H.K. Ober, E.C. Braun de Torrez, J.A. Gore, R. Zambrano
Materials and Methods
Historical Roosts
We used two approaches to compile a comprehensive list of all known roosts used by
Florida Bonneted Bats in the greater Miami area prior to the species’ listing as federally en-
dangered in 2013, which we refer to as the historical period. First, we completed a thorough
literature review of all reports using the Web of Science (Thomson Reuters) database. Be-
cause the species name has changed over time from Eumops glaucinus to Eumops glaucinus
floridanus to Eumops floridanus, we used each of these three scientific names as keywords
in our search as well as "Florida Bonneted Bat”, “Florida Mastiff Bat”, “Wagner’s Mastiff
Bat”, OR “Florida” AND “bat”. The literature search included publications between 1900
and 15 August 2020. We then searched the reference lists of these publications for addi-
tional relevant sources. Second, we contacted the four museums that hold E. floridanus or
E. glaucinus floridanus specimens (American Museum of Natural History in New York,
NY; Field Museum of Natural History in Chicago, IL; Florida Museum of Natural History
in Gainesville, FL; and Kansas University Natural History Museum in Lawrence, KS) and
requested details on the location where each specimen was obtained. From each published
report and each museum specimen, we recorded information on roost location, and for those
reported in buildings, we used publicly available information from commercial realty web-
sites to determine the year built and architecture type.
Recent Roosts
We also used two approaches to document structures used as roosts by Florida Bonneted
Bats in Miami recently, which we define as the period starting when the species was listed as
endangered in 2013 until 2020. First, we compiled a list of all reports to FWC, USFWS, and
University of Florida (UF) during this period. Reports included written, oral, and electronic
communication. Second, we captured bats and radio-tracked them to roost sites.
We selected four semi-natural areas evenly distributed across the greater Miami area
where Florida Bonneted Bats had been detected acoustically (Marks and Marks 2012; F.
Ridgley, Zoo Miami, Miami, FL, 2014 pers. comm.) to serve as potential bat capture loca-
tions. The southernmost area was Zoo Miami, located in Miami; the northernmost and east-
ernmost locations were the Granada Golf Course and Fairchild Tropical Botanic Garden in
Coral Gables; and the remaining site was Kendall Indian Hammocks Park in Kendall (Fig.
1B). We attempted to capture bats in each area during June and July 2017 by setting up
triple-high stacked mist nets on 7.3-m poles (Bat Conservation and Management, Carlisle,
PA) at two locations within Zoo Miami, three locations within the Granada Golf Course,
two locations within Fairchild Tropical Botanic Garden, and two locations within Kendall
Indian Hammocks Park. Mist nets were opened shortly before sunset, closed at 0200 h, and
checked every 10 minutes. Short-duration rain events were common many evenings; we
paused capture efforts whenever precipitation began and resumed once it ended. Adjacent
to each net, we situated an acoustic lure (BatLure™, Apodemus Field Equipment, Mheer,
Netherlands) to attract bats to the net. The lure broadcast Florida Bonneted Bat social calls
pre-recorded from a roost in Florida Panther National Wildlife Refuge, which is a tactic
demonstrated to markedly increase the capture rate of this species in mist nets (Braun de
Torrez et al. 2017). We netted for 26 nights: 18 nights at Granada Golf Course, two nights
at Fairchild Tropical Botanic Garden, three nights at Zoo Miami, and three nights at Kendall
Indian Hammocks Park.
32021 Urban Naturalist No. 42
E.N. Webb, H.K. Ober, E.C. Braun de Torrez, J.A. Gore, R. Zambrano
We recorded age, sex, reproductive status, mass, and forearm length for each captured
individual. Age was categorized as adult or juvenile, determined by the degree of fusion of
epiphyseal cartilages in the fourth metacarpal-phalangeal joint (Kunz and Anthony 1982).
Reproductive status for females was categorized as nonreproductive, pregnant, lactating,
or postlactating through palpation of the abdomen, presence of swollen nipples or milk.
Reproductive status for males was categorized as nonreproductive or reproductive through
the presence of abdominal or descended testes. We calculated body condition index (mass/
forearm length) of each individual to serve as a relative measure of bat condition (Jonas-
son and Willis 2011, Reynolds et al. 2009) that could be compared with reports for Florida
Bonneted Bats roosting in a natural area (reported in Ober et al. 2017b).
We attached VHF radio-transmitters (model LB-2, Holohil Systems Ltd., Carp, On-
tario, Canada) to all Florida Bonneted Bats captured, with the exception of juveniles,
pregnant or lactating female adults, or any bat for which the mass of the transmitter would
exceed 5% of the bat’s mass (Aldridge and Brigham 1988), in accordance with our permit
(TE23583B-2) and protocol approved by University of Florida IACUC (#201609497). Each
radio-transmitter was sewed onto a break-away collar closed with absorbable suture, and
each individual was released at the site of capture immediately after collar attachment.
Each bat to which a transmitter was attached was tracked by vehicle and on foot during
subsequent days until a structure used as a roost was identified. Each roost structure identi-
fied was verified with emergence observations after sunset that included colony size counts.
Because Florida Bonneted Bats typically emerge from their roosts long after sunset, and
because of the challenges associated with observing the emergence of bats from buildings in
residential areas with high housing densities, it was generally not possible to discern what
portion of each building bats were emerging from (e.g., beneath roof tiles, from chimney).
Lastly, we recorded information on the architecture of each building used as a roost and the
year it was built.
Results
Historical Roosts
Publications and museum records confirmed that Eumops specimens were collected
regularly in buildings in Miami during the 3-decade period extending from the mid-1930s
to the mid-1960s (Table 1; Figs. 1B, 1C). The first record of Eumops in Miami indicated
a bat was found by a student from “Edison High School” (Barbour 1936), likely Miami
Edison Senior High School located in Miami, but no indication of the location where
the bat was originally found was provided, so it is not included further in our analyses.
Schwartz (1952) subsequently described 5 male specimens recovered from the gymnasium
and grounds of “Miami High School” during the preceding 10 years (i.e., 1942–1952). As
the oldest high school in the county, Miami High School (i.e., Miami Senior High School)
has been in its current location since 1928 and is noted for its Mediterranean Revival ar-
chitecture. Jennings (1958) reported that 20 Florida Bonneted Bats had been collected from
Coral Gables, Coconut Grove, and Miami since the first report by Barbour in 1936, but
did not specify precise locations from which they originated. Robson (1989) reported that
Florida Bonneted Bat specimens were collected regularly in Miami during the midcentury.
In a table summarizing all bat specimens available in museums in 1989, he documented
18 individuals collected in the greater Miami area. These included three bats from Miami
High School, three from North Miami High School, one male from University of Miami
in Coral Gables in 1955, two males from chimneys in homes in Coral Gables in 1961 and
4Table 1. Description of buildings used by Florida Bonneted Bats, Eumops floridanus, in Miami, FL, indicating the year bats were observed, type of building, 2021
type of architecture, year built, location within Miami, description of bat use, and method used to determine use. Numbered superscripts denote museum reports,
and lettered superscripts denote published reports.
Year used Type of structure Architectural Year built Location in Description of bat use Location method
by bats type greater Miami
area
1949, 1951, Miami High School Mediterranean 1928 Miami 7 individuals found singly Museum1,2, indirect reporta,b
1953 (i.e., Miami Senior
High School)
1952 North Miami High Other 1951 North Miami 4 individuals Museum2, indirect reportb
School
1955 University of Miami Unknown Unknown Coral Gables 1 male Indirect reportb
1961 House Unknown Unknown Coral Gables 1 male in house chimney Indirect reportb
1962 House Unknown Unknown Coral Gables 1 male in house chimney Indirect reportb
1988 Office Building Art deco 1986 Coral Gables 1 female on exterior balcony Citizen reportc
5
1995 House Mediterranean 1926 Coral Gables 1 male entered through chimney Homeowner reportd
1997, 2014, House Mediterranean 1929 Coral Gables 1 male entered through chimney, Homeowner reportd, citizen
Urban Naturalist
2017 colony roosted, 1 male roosted scientistse, radio- telemetry
2015 Condominium Other 1981 Kendall Colony (n = 10) roosted Building renovator report
2017 House Other 1986 West Kendall 1 male roosted Radio-telemetry
2017 House Mediterranean 1925 Coral Gables 1 male roosted Radio-telemetry
2017 House Mediterranean 1928 Coral Gables Colony (n = 10) roosted Radio-telemetry
2018 House Mediterranean 1925 Coral Gables 1 male entered through chimney Citizen report
2020 Bell tower Mediterranean Unknown Pinecrest Colony (n = 15) roosted Citizen report
E.N. Webb, H.K. Ober, E.C. Braun de Torrez, J.A. Gore, R. Zambrano
1
Field Museum of Natural History, Chicago, IL
2
Florida Museum of Natural History, Gainesville, FL
a
Schwartz 1952
b
Robson 1989
c
Robson et al. 1989
d
No. 42
Gore et al. 20152021 Urban Naturalist No. 42
E.N. Webb, H.K. Ober, E.C. Braun de Torrez, J.A. Gore, R. Zambrano
1962 (Robson 1989), and one female from an office building balcony in Coral Gables in
1988 (Robson et al. 1989). Collection locations for eight other records simply indicate Cor-
al Gables (n = 7) or Miami (n = 1). The only published records of Florida Bonneted Bats
collected in the greater Miami area anywhere other than in buildings included three bats
reportedly taken on the ground (two of which were associated with construction projects),
all undated but presumably midcentury (Owre 1978); one bat under rocks in Coral Gables
in 1955 (Robson 1989); bats taken in low shrubbery, undated but presumably midcentury
(Jennings 1958); and bats in shafts of royal palm leaves, undated (Belwood 1992).
Our review of records obtained directly from the four museums now housing E.
floridanus/E. glaucinus floridanus specimens documented six additional records, leading to
a total of 20 individuals collected in the greater Miami area between 1949 and 1965. Only
10 of these records had precise descriptions of locations where specimens were collected;
all 10 were from either Miami High School or North Miami High School.
No specimens were reported during the 21-year period extending from 1966 to 1987,
leading to speculation that the species might have been extirpated from the region (Belwood
1992). Subsequently, a single pregnant female Florida Bonneted Bat was found roosting on
the 7th-floor balcony of an office building in Coral Gables in 1988 (Robson et al. 1989). A
single male Florida Bonneted Bat entered a home in Coral Gables through a chimney in
1995, and another male Florida Bonneted Bat entered a home with Mediterranean Revival
architecture in Coral Gables through a chimney in 1997 (Gore et al. 2015). Following these
records, there was again a period with no confirmed specimens in Miami for well over a
decade (1998–2013), although acoustic surveys suggested the species persisted (Marks and
Marks 2012).
Recent Roosts
Four incidents of Florida Bonneted Bats in buildings have been reported to FWC, US-
FWS, and/or UF since the species was federally listed (i.e., 2013–2020; Fig. 1B). The first
was a colony of bats tracked through auditory means to a home in Coral Gables in 2014 by
a Miami-based group of citizen scientists, the Bat Squad (Staletovich 2014). This colony of
bats emerged from beneath the clay tile roof of the same home with Mediterranean Revival
architecture that a male Florida Bonneted Bat had entered through a chimney in 1997 (Gore
et al. 2015). The second was a colony auditorily identified as Florida Bonneted Bats roost-
ing in two condominiums located in a complex in Kendall in 2016. The third was a single
male bat found within the living space of a home with Mediterranean Revival architecture
in Coral Gables in 2018; the homeowner believed the bat had entered through the chimney.
The fourth was a colony of bats located in a church bell tower in Pinecrest when the clay
tile roof was removed in 2020. The species identities of individuals in the third and fourth
incidents were confirmed by a local veterinarian (F. Ridgley, 2020, pers. comm).
During our radio-telemetry effort to locate roosts in 2017, we captured 11 Florida Bon-
neted Bats in greenspaces within the greater Miami area. Eight of these individuals were
captured at Granada Golf Course, two at Zoo Miami, and one at Kendall Indian Hammocks
Park; none were captured at Fairchild Tropical Botanic Garden. We captured four adult
males, three subadult males, three adult females, and one subadult female. One adult female
was pregnant and another was lactating, confirming that bats in the greater Miami area were
reproductively active.
We deployed transmitters on five bats (one adult female and four adult males), which
led us to discover four roost structures, all located in residences (Figs. 1B, 1C). One home,
located 5.8 km west of the capture site, was used by a lone male captured at Kendall Indian
62021 Urban Naturalist No. 42
E.N. Webb, H.K. Ober, E.C. Braun de Torrez, J.A. Gore, R. Zambrano
Hammocks Park. The other three homes were in Coral Gables, had Mediterranean style
architecture, and were within one km of each bat’s capture site, the Granada Golf Course.
Two of the homes used in Coral Gables were vacant and undergoing renovation. One of
these vacant homes was used as a roost by a colony of at least 10 Florida Bonneted Bats,
and the other which was the same home where Florida Bonneted Bats had been documented
in 1997 and 2014, was used by a lone male. The third home used in Coral Gables was also
used by a lone male.
The body condition indices (BCI) of bats of all sex and reproductive condition catego-
ries captured during this investigation were lower than those reported for Florida Bonneted
Bats in a natural area (Ober et al. 2017b) (Table 2). Small sample sizes precluded our ability
to determine if differences were statistically significant.
Discussion
There is a long history of building use by Florida Bonneted Bats in the greater Miami
area, the most urbanized region in Florida, despite urban intensification. This species was
first documented in the region in the 1930s, when Miami-Dade County had2021 Urban Naturalist No. 42
E.N. Webb, H.K. Ober, E.C. Braun de Torrez, J.A. Gore, R. Zambrano
with this architecture, as two of the three roosts reported by citizens and three of the four
roosts identified through radio-tracking were homes with similar architectural features. In-
terestingly, bats used one of the same homes in 2017 that they had used in 1997 and 2014,
despite the choice of millions of artificial structures across the 150 km2 area comprising the
greater Miami area. This residence was located within a neighborhood in Coral Gables used
consistently by Florida Bonneted Bats over the past three decades (Fig. 1C). Future research
should investigate what specific aspects of the buildings selected by Florida Bonneted Bats
in urban areas attract the bats. We found it difficult to distinguish exactly where bats were
exiting from structures during emergence observations and therefore recommend the use of
infrared or thermal-imaging video cameras during future emergence observations to build a
deeper understanding of which portion of the buildings bats are using as roosts. Character-
istics of homes in Coral Gables that may be appealing to roosting bats are the clay tile roofs
that provide ample crevices, the stucco substrate that minimizes temperature fluctuations,
the unusual chimney features typical of Mediterranean Revival homes, or the large yards
with lush vegetation that are more prevalent in this region than elsewhere in the greater
Miami area (Nijman and Clery 2015). The recent documentation of Florida Bonneted Bats
roosting in Kendall and Pinecrest, two regions that have not experienced the densification of
buildings typical of much of the rest of the greater Miami area, suggests Florida Bonneted
Bats may prefer areas with lower building densities and greenery (Nijman and Clery 2015).
Alternatively, it may be the clay tile roof of the belltower in Pinecrest, which is similar to
Figure 2. Many buildings established in Miami during the 1920s and 1930s featured Mediterranean Revival
architecture, characterized by elements depicted here, which may attract Florida Bonneted Bats, Eumops
floridanus. Illustrative credit: Elizabeth Braun de Torrez.
82021 Urban Naturalist No. 42
E.N. Webb, H.K. Ober, E.C. Braun de Torrez, J.A. Gore, R. Zambrano
that of many homes used as roosts in Coral Gables, that attracted bats to roost there. Clearly,
additional investigation is warranted to determine the relative importance to the bats of fac-
tors such as roofing material, building style, chimney architecture, and vegetation.
In contrast to natural areas, where Florida Bonneted Bats regularly roosts in trees (An-
gell and Thompson 2015; Braun de Torrez et al. 2016, 2020 unpubl. data), use of vegetation
by the species in Miami has not been documented in recent years. The last time Florida
Bonneted Bats were reported using natural vegetation in the greater Miami area was at least
3 decades ago, and it has possibly been much longer (bats taken from low shrubbery re-
ported in Jennings 1958; bats found in shafts of Roystonea regia Kunth reported in Belwood
1992; neither reported precise locational information or the year of these observations). It
is unclear whether bats in this urban region have been using buildings exclusively during
recent times because these structures provide roost conditions superior to those provided
by natural vegetation, whether vegetation with requisite characteristics has become limited
in availability over time, or whether bats have continued to use both natural and artificial
structures, but the former have not been investigated with adequate intensity to detect use.
To date, the greater Miami region is the only area within the species’ geographic range
where Florida Bonneted Bats have been reported to roost in buildings. Additional research
in other urban areas is recommended to determine if this pattern reflects a true lack of use
of buildings by the species in any other urban area.
We recommend comparisons of demography and fitness of Florida Bonneted Bats roost-
ing in urban areas relative to bats roosting in natural areas to determine if urban conditions
impart negative long-term population level impacts. Larger sample sizes are needed to
confirm or refute the trends suggested by the data reported here. The comparatively lower
body condition indices of bats of all sex and reproductive condition categories captured
during this investigation relative to those reported for Florida Bonneted Bats in a natural
area suggest that individuals in urban areas may be less fit. These differences may be due
to increased stress experienced by bats in Miami compared to natural areas, perhaps due to
artificial light pollution, elevated noise levels, or inferior diets (Jung and Threlfall 2016).
We also recommend additional research to clarify the timing of reproduction of urban
Florida Bonneted Bats. Given that purposeful exclusions of bats from buildings and roof
renovations are two primary pathways through which bat mortality or injury could occur
in urban areas, a better understanding of the timing of reproductive peaks among urban
populations of Florida Bonneted Bats could enable refinement of guidelines pertaining to
such activities. Currently, bats of all species cannot legally be excluded from man-made
structures in Florida when non-volant pups are present, which is designated as the period
extending from 15 April to 15 August (Florida Administrative Code Chapter 68A-4.001
and 68A-9.010). Research on Florida Bonneted Bats in a natural area in southwest Florida
suggests that the species may be aseasonally polyestrous with a peak pregnancy period in
spring (Ober et al. 2017a). A clearer understanding of when non-volant pups are least likely
to be present in buildings in urban areas would enable refinement of guidelines so that dis-
turbance to these bats is minimized during periods when they are most vulnerable.
Current guidelines specify that, if bats are discovered in a building undergoing renova-
tion at any time of year within the geographic range of Florida Bonneted Bats, consultation
with USFWS should occur prior to proceeding if the bats are suspected to be Florida Bon-
neted Bats (Florida Bonneted Bat Consultation Guidelines, available at https://www.fws.
gov/verobeach/ListedSpeciesMammals.html). This suggests the need for an educational
campaign to increase awareness that an endangered species of bat sometimes resides in
buildings in Miami. Such a campaign should include homeowners, who might encounter
92021 Urban Naturalist No. 42
E.N. Webb, H.K. Ober, E.C. Braun de Torrez, J.A. Gore, R. Zambrano
bats but consider them to be a nuisance or a human health concern and be unaware that
the animals are protected by conservation regulations or be unable to identify the species.
Efforts should prioritize those areas—such as Coral Gables—where older homes (built in
the 1920s and 1930s) are most common, particularly those with Mediterranean architec-
ture. Also, a training program should target individuals in professions likely to encounter
roosting bats, such as roofers and nuisance wildlife control operators, to ensure they can
identify Florida Bonneted Bats, know who to contact if they suspect they have found this
species, and are aware of the time of year of bat eviction restrictions.
Our study provides the initial foundation for understanding roost use by Florida Bon-
neted Bats in urban areas and highlights aspects of roost use about which our knowledge is
limited. As urbanization continues throughout south and central Florida, additional research
and targeted education efforts can play a critical role in the development and adoption of
appropriate conservation actions to ensure the continued existence of Florida Bonneted Bats
in Miami and other urban areas across the species’ range.
Acknowledgments
We thank Shalana Gray for participating in all aspects of field work. We also thank the following
individuals for facilitating access to properties where captures were attempted and assisting with radio-
tracking and/or roost emergence observations: Troy Hall, Amy Padolf, Frank Ridgely, Eduardo Sal-
cedo, and Sonya Thompson. We also thank Adam Ferguson, Verity Mathis, and Sandra Sneckenberger
for providing information. Lastly, we thank FWC, UF, and Bat Conservation International for funding.
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