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Perimyotis subflavus (Tricolored Bat) was once common across the eastern United States, but in recent years, populations have declined drastically across the species' range, mainly because of mortality caused by white-nose syndrome. The fungus that causes white-nose syndrome has not been detected in Florida, and therefore the state may represent an important stronghold for the Tricolored Bat. We counted Tricolored Bats in Florida caves in January and February from 2014 to 2022 to better determine population size and document trends in abundance before the potential arrival of white-nose syndrome. We modeled trends in counts over time on the entire count dataset and on subsets based on karst region and cave size. In addition, we fit mixed-effects Poisson regression models to understand the influence of cave characteristics and investigator disturban ce on Tricolored Bat counts. Models of statewide bat counts exhibited a strongly decreasing trend (mean = -17% per year) with a 67% decrease overall across the study period. Warmer temperatures on the day of survey were associated with lower counts, and longer caves were associated with higher counts. We did not find an impact of investigator disturbance on bat counts. Although ambient temperatures influenced observed numbers, we cannot exclude the possibility that these long-term declines are the result of undetected or indirect losses from white-nose syndrome. It is unknown if Tricolored Bats roosting in other locations that are not routinely monitored (e.g., trees) are experiencing similar declines; thus, incorporating other monitoring methods would improve the understanding of Tricolored Bat population trends. [ABSTRACT FROM AUTHOR]

Background: Animal migration is a widespread global adaptation by which individuals move in response to environmental conditions to reach more favorable conditions. For bats in temperate climates, migration and hibernation are often associated with each other when these bats must migrate to reach suitable overwintering sites. However, differences in movement across the geographical range of a species and the degree to which hibernation drives migratory behavior of bats in subtropical climates, where conditions may remain warm with available prey year-round, remains incomplete. Understanding the migratory strategies of subtropical bats during winter is of increasing importance as they are threatened by stressors such as disease and environmental change. Methods: We evaluated migration patterns of tricolored bats (Perimyotis subflavus) in Florida, USA, through analysis of stable hydrogen isotope ratios of the fur. We inferred the summer geographic origins of the fur samples and estimated the minimum distance and likely direction traveled by hibernating individuals. We used linear models to examine whether hibernation region, colony size, and an individual's sex affected the distance traveled. Results: We sampled 111 bats hibernating at 40 sites and found that more than half (54.1%) of individuals were residents of the area in which they hibernated. We found that almost half of the sampled bats (43.2%) traveled from southern Florida to overwinter in North Florida. We also documented three individuals that traveled > 100 km from northerly origins, one of which had traveled an estimated minimum distance of 1382 km. We also found that tricolored bats moved farther to reach hibernacula in Northwest Florida and hibernacula with more populous colonies, with no difference in movement between sexes. Conclusions: Our results indicate a pattern of northward autumnal movements of tricolored bats in the subtropical southeastern portion of their range. We suggest that bats are differentially constrained at the edge of their geographical range, resulting in movement contrary to what is expected. Even though we found that few (2.7%) bats moved into Florida from farther north, those migrants can potentially transfer the fungus that causes the deadly white-nose syndrome, which does not currently occur in the state. Our results support the characterization of tricolored bats as flexible partial migrators, with a rarely exercised capacity for long-distance movements. [ABSTRACT FROM AUTHOR]

Many cave-roosting bats are declining in number throughout their range because of multiple threats, including disease, disturbance by humans, and habitat loss. Successful conservation of cave-roosting bats requires an understanding of the roles of microclimate, cave structure, and the surrounding landscape on the distribution and abundance of bats, and in particular, the use of winter cave roosts. Cave bats have been well studied in temperate climates, but we know little about these bats in subtropical climates. From 2015 to 2017, we conducted 399 winter surveys of 162 caves in Florida to evaluate factors affecting the presence and abundance of bats at cave roosts. We also determined whether temperatures at these cave roosts were suitable for Pseudogymnoascus destructans, the fungus that causes white-nose syndrome. Across all 3 y, we detected three species of bats: tricolored bat Perimyotis subflavus in 126 (77.8%) caves, southeastern myotis Myotis austroriparius in 51 (31.5%) caves, and a single Rafinesque's big-eared bat Corynorhinus rafinesquii. We analyzed the presence of both tricolored bats and southeastern myotis in caves by using mixed-effects models with a binomial distribution and the number of tricolored bats by using generalized linear mixed-effects models with a Poisson error distribution. Tricolored bat presence was significantly and positively influenced by a cooler cave surface temperature, larger cave entrance size, a single entrance, and the presence of solution holes. Tricolored bat abundance increased in longer, cooler caves that had solution holes, a single, unobstructed entrance, and had no signs of flooding. Southeastern myotis presence was positively associated with longer, domed caves. To be most effective, conservation efforts in subtropical climates should focus on caves with the identified characteristics. More than 90% of caves surveyed each year had a cave interior surface temperature below the upper critical growth limit for P. destructans (19.8°C), indicating that most Florida caves are suitable for growth of P. destructans. Therefore, regular monitoring of winter bat populations in subtropical caves may be important for detecting P. destructans and white-nose syndrome. [ABSTRACT FROM AUTHOR]

Corynorhinus rafinesquii (Rafinesque's Big-eared Bat) is uncommon and unevenly distributed throughout its range, and its populations are believed to be declining. The distribution in Florida, the southernmost extent of the range, is unclear, and recently published maps show records in only 16 counties scattered across the state. We compiled published and unpublished records of Rafinesque's Big-eared Bat in Florida and found 59 total records, including records from 13 counties where the species had not been previously reported. These new records expand the known distribution in Florida to 29 counties, including Miami-Dade County in extreme southeastern Florida. Our compilation of records clarifies the species' distribution in Florida, but several broad geographic areas still lack records despite the presence of forested wetland habitat potentially suitable for Rafinesque's Big-eared Bat. We recommend further survey efforts for Rafinesque's Big-eared Bat in 4 areas we identified where the species may be present. [ABSTRACT FROM AUTHOR]

Aberrant patches of white skin or fur known as hypopigmented marks have been observed in many mammal species worldwide, but they are typically limited to only a few individuals in a population. Hypopigmented marks were documented in only two museum specimens of the federally endangered Florida bonneted bat (Eumops floridanus) as early as 1950, but recent observations suggest that these marks may be more common in this species than previously believed. To better understand the occurrence and persistence of hypopigmented marks in Florida bonneted bats, we evaluated the variation in frequency, compared effects on survival, and assessed spatial and temporal differences of specimens at an intensively studied site and across the species range. From 2014 through 2017, we regularly captured Florida bonneted bats for demographic studies at Babcock–Webb Wildlife Management Area in Charlotte County and we observed hypopigmented marks on 172 (80.8%) of 213 individuals, the highest incidence known for bats. The proportion of hypopigmented marks did not differ with sex, age at first capture, or reproductive status, and importantly, we documented the persistence of hypopigmented marks in individuals over multiple months. We also found no difference in survival or capture probability between hypopigmented and solid-colored individuals. Using data from concurrent mist-net studies, we assessed the proportion of Florida bonneted bats with hypopigmented marks across the species range and found a higher proportion of individuals with hypopigmented marks in the two northern counties (80.8% in Charlotte County and 61.5% in Polk County) compared with the two southern counties (21.1% in Miami–Dade County and 16.7% in Collier County). Additionally, we compared the proportion of hypopigmented individuals in Miami–Dade County between recently captured/collected bats (post-2004) and historically (pre-1965) collected museum specimens and found more hypopigmented marks in recently captured bats. The persistence of hypopigmented marks over time, the presence of marks on bats from different locations, and our finding of no effect of age on the presence of marks all strongly suggest that the hypopigmented marks in Florida bonneted bats are the result of genetic rather than environmental factors. Further study is required to understand the mechanism underlying the high incidence of hypopigmented marks and to determine whether the prevalence of hypopigmented marks indicates low genetic diversity that could threaten Florida bonneted bats. [ABSTRACT FROM AUTHOR]

Once on the brink of extinction, the Florida panther (Puma concolor coryi) has reoccupied parts of its extirpated range in southern Florida, USA over the past 20 years, which has largely been attributed to genetic restoration efforts initiated in 1995 to combat inbreeding depression and subsequent deleterious traits. Concurrent to the resurgence, an increase in documented livestock depredation events has heightened concern over human-- panther conflicts. We examined 312 stomach content, scat, and feces (large intestine contents) samples collected 1989 to 2014 across the endemic range in southern Florida. We compared frequency of occurrence of prey items in samples by temporal (pre- and postgenetic restoration), geographic (north and south of 26° 10.017' latitude), and demographic (age and sex) categories. We observed an apparent temporal shift in prey item occurrence in scats, where raccoon (Procyon lotor) occurrence increased while wild hog (Sus scrofa) occurrence decreased, whereas white-tailed deer (Odocoileus virginianus) occurrence appeared constant. Post-genetic restoration, we observed a geographic difference in panther prey, where white-tailed deer and raccoons were consumed more commonly in the southern part of the study area (characterized by lower soil quality and higher hydrological fluctuations), while wild hogs were consumed more frequently in the northern part of the study area. Neither sex nor age appeared to affect frequency of prey occurrence. Pets and livestock were not frequently found in the samples we examined. Overall, our results show shifts in panther diets both temporally and geographically; however, no notable changes in frequency of livestock found in panther diets were observed. [ABSTRACT FROM AUTHOR]

Using the approach established by EPA's Environmental Monitoring and Assessment Program (EMAP), a shoreline monitoring survey was conducted in August and September 1999, encompassing the Florida Panhandle from Perdido Key, Florida to Port St. Joe, Florida. The objective of this survey was to demonstrate the use of a probabilistic survey for monitoring and estimating the condition of swimmable beach areas. Thirty stations were sampled using a probabilistic sampling design. Hydrographic data were collected in addition to samples for water chemistry. Bacterial indicators, enterococci and fecal coliforms, were enumerated from the water according to the EPA Beaches Environmental Assessment Closure and Health (BEACH) Program and Florida state guidelines. Additional criteria for site condition included the presence or absence of primary and secondary dunes, anthropogenic debris and vegetation. Based on EMAP evaluation guidelines and Florida state criteria, a baseline assessment of the condition of the Gulf of Mexico beach resources surveyed is presented.

In 1999, the United States Environmental Protection Agency Gulf Ecology Division initiated a pilot study to assess the condition of nearshore coastal resources. Near-shelf areas associated with coastal beaches are susceptible to land based activities, but are not consistently monitored. Additionally, few or no marine water quality criteria exist for evaluating these waters. The goal of this pilot study was to assess the ecological condition of Gulf of Mexico near-shelf resources using a probability-based survey design. Data are used to generate a baseline assessment of condition in coastal nearshore areas and provide a comparative tool for evaluating future trends in condition. Water quality, sediment quality and benthic diversity data can provide a baseline assessment for managers to evaluate the potential for future problems such as nutrient over-enrichment, sediment contamination and degraded biological condition. We present results from a probability-based survey demonstration assessing near-shelf resources along the Florida panhandle.