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Mosquitoes affect human health and well-being globally through their roles as disease-causing pathogen vectors. Utilizing genetic techniques, we conducted a large-scale dietary study of three bat species common to the southeastern U.S.A.

Knowledge of genetic structure is essential for the long-term management and conservation of endangered species. We report the results from a genetic examination of the federally endangered Florida bonneted bat (Eumops floridanus) sampled from its range in southern Florida, USA. Bonneted bats are primarily found in four regions separated by approximately 100 to 250 kms, including three western natural areas (BW, PC, and CC) and one urban population on the east coast [Miami-Dade County (MD)]. We used 22 microsatellite loci and cytochrome b sequences to assess the extent of connectivity and levels of genetic diversity. Regional populations were highly differentiated (FST = 0.178) and model-based and multivariate analyses showed that MD was the most distinct among pairwise comparisons. Regional populations are small (i.e., Ne < 100) but demographically stable. Estimates of contemporary migration and historic gene flow suggest that regional populations do not frequently exchange migrants, but simulations suggest that the divergence among western regions is likely a result of recent genetic drift rather than long-term isolation. Significantly, mitochondrial DNA revealed that haplotypes from MD were similar or shared with those recognized as Eumops ferox from Cuba and Jamaica, and divergent (1.5%) from the remainder of bonneted bats in Florida. Our data support the management of each of the four populations as distinct population segments, and that BW, PC and CC combined are on an independent evolutionary trajectory from bats in MD. Critically, bonneted bats in Florida appear to harbor cryptic diversity that will require a reassessment of their taxonomy.

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.

Climate change will alter natural areas on a global scale within the next century. In areas vulnerable to climate change, scientists are regularly challenged to justify the resources needed for research and conservation. We face what may seem like a losing battle, especially in low-lying coastal areas where sea-level rise is predicted to severely degrade or destroy many ecosystems. Using sea-level rise in the low-elevation state of Florida, USA, as a case study, we argue that it is critical to remain engaged in the research, restoration, and conservation of natural areas threatened by climate change for as long as possible. These areas will continue to provide invaluable ecological and societal benefits. Additionally, uncertainty surrounding climate change forecasts and their ecological impact leaves room for optimism, research, and actions that are necessary for developing adaptation plans and mitigating further sea-level rise and other consequences of climate change. We urge scientists and particularly students beginning their careers not to forego research and conservation efforts of these imperiled lands but to face this unprecedented challenge with determination, creativity, and solution-based strategies.

Global biodiversity patterns are shaped by landscape structure and seasonality. Spatio-temporal patterns in bat assemblages are not well studied in grassland biomes but forest patches may provide important habitat for bats within these open grasslands. In the Greater Everglades Ecosystem (GEE), small fragments of diverse, critically imperiled pine rockland remain amidst a vast expanse of seasonally flooded grasslands (marl prairies). We used acoustic surveys to investigate the use of pine rocklands and marl prairies by bats across 2 distinct seasons (dry-cool and wet-warm). We detected higher mean bat activity in pine rocklands than marl prairies in the dry-cool season and higher bat species richness in pine rocklands in both seasons. Four of the 9 species of bats exhibited higher mean activity in pine rocklands than marl prairies and higher activity in the wet-warm season. The greater structural complexity of pine rocklands relative to marl prairies may be attractive to bats for roosting, foraging, and protective cover. Our finding of an interactive effect between vegetation community and season on bat activity suggests that pine rocklands may be more attractive to bats in the dry-cool season. This may be due to microclimate moderation, which likely leads to higher insect abundance for foraging bats. Pine rocklands in the GEE clearly provide ecological benefits that help support local biodiversity. These forest patches are important landscape elements for bats in grassland communities, where available roosts, prey, and protective cover may be limited.

As generalist predators, insectivorous bats exploit fluctuations in prey distribution and abundance. A more nuanced understanding of the influence of bats on arthropod pests requires documentation of the pest species bats consume and of the conditions associated with variation in rates of pest consumption. Here, we used high-throughput metabarcoding of DNA extracted from bat feces to investigate diets of 180 bats representing three Vespertilionidae species common to the southeastern US, a region dominated by agriculture and pine plantations. We detected 23 species of agricultural pests in bat diets, including pests responsible for severe economic damage, such as Helicoverpa zea, Spodoptera frugiperda, Chloridea virescens and Chrysodeixis includens. Incidence of pest consumption was high: 61% of all bats had consumed at least one agricultural pest species, with each bat consuming an average of 1.7 pest species. The likelihood of consumption of pests to row crops and the average size of pests consumed varied by bat species, with a large foliage-roosting species (Lasiurus seminolus) consuming a greater variety of pest species and pest species larger in size than smaller crevice, cavity, and cave roosting bat species (Nycticeus humeralis, Myotis austroriparius). Likelihood of pest consumption also varied among sampling periods (season) and among bats of different sizes (as reflected by wing length and mass). Overall, likelihood of pest consumption was higher in the late summer season than during spring or early summer, and higher among larger bats than smaller bats. Bat characteristics and seasonality were generally more effective than geographic features and weather conditions in predicting pest consumption patterns. Strategies for enhancing pest consumption services by bats in agroecosystems should strive to maintain and enhance diverse bat populations on a landscape scale by protecting and augmenting roost structures appropriate for each species. Our finding of widespread pest consumption by bats contributes to mounting evidence worldwide of the important role bats play in agricultural systems and highlights the value of incorporating bat conservation into integrated pest management programs globally.

Many Chiropteran species are gregarious, yet much remains to be learned about details of the sociality of most species. This is especially true for the endangered Eumops floridanus (Florida bonneted bat). Scant knowledge of the species’ natural history and ecological interactions has precluded the development of effective conservation strategies. We investigated several aspects of the social organization of E. floridanus roosting in bat houses in southwest Florida: group size, group composition, group stability, and seasonality of reproduction. Our findings suggest the species has characteristics more common to tropical bat species than temperate ones. The average roost size was 10 individuals, with colonies in a harem social structure all three times in the year they were assessed. Adults were much more likely than sub-adults to be recaptured at the same roosts during subsequent capture sessions. We suggest that the availability and distribution of roosts may alter the social structure of these bats and ultimately limit local populations. We did not find evidence of a distinct seasonal birthing period matching that of other temperate bat species. Results suggests the species is aseasonally polyestrous, making non-volant E. floridanus vulnerable to disturbance across a larger portion of the year than other bat species in the US.

Effective strategies for bat conservation require knowledge of species-specific roost ecology. Thus, conservation planning is difficult for species with poorly understood roost use, such as the federally endangered Eumops floridanus (Florida Bonneted Bat). Prior to this study, only 1 active natural roost had been documented throughout the Florida Bonneted Bat's geographic range. Search efforts to locate new roosts using several techniques have been unsuccessful. Here we present a simple methodology that we successfully implemented to locate a second Florida Bonneted Bat natural roost. Using acoustics, cavity searches, and emergence observations, we documented a colony of Florida Bonneted Bats roosting in a Pinus elliottii (Slash Pine) snag in Florida Panther National Wildlife Refuge in Collier County, FL. Our discovery highlights the importance of snags, and provides additional details to state and federal agencies tasked with species recovery.

Fire suppression has altered ecological communities globally. Prescribed fire regimes strive to restore function to these fire-dependent ecosystems by mimicking natural fire regimes. Although fire frequency is a widely acknowledged component of fire regimes, the importance of fire seasonality for biodiversity is less clear but appears to play a critical role for a variety of taxa, particularly in the North American Coastal Plain. In subtropical Florida, USA, fire historically occurred primarily at the transition from the dry to wet season (early wet season: April to June) when dry fuel accumulation coincides with a high incidence of lightning. We investigated the effects of fire frequency and season on endangered Florida bonneted bats (Eumops floridanus [G.M. Allen, 1932]), a species endemic to a region that evolved with frequent fires. We surveyed bat activity acoustically in 149 sites in fire-dependent vegetation communities (pine flatwoods and prairies), and evaluated the effects of fire frequency and seasonality, using burn records from the previous 18 years. Variation in bat activity was best explained by both fire frequency and season: bat activity decreased with early wet season (April to June) burn interval and increased with dry season (November to March) burn interval. Bat activity and foraging activity were highest in sites burned at > 3- to 5-year intervals during the early wet season. Fires during the historic fire season at a moderate frequency (> 3 to 5 yr) appear to optimize habitat for bats in both pine flatwoods and prairies, likely through increases in roosts, flight space, and insect prey availability. It appears that Florida bonneted bats are fire-adapted and benefit from prescribed burn programs that closely mimic historical fire regimes. We encourage consideration of both fire frequency and seasonality when managing ecosystems with fire.