Bat Dispersal Research Articles

Ectoparasite and bacterial population genetics and community structure indicate extent of bat movement across an island chain.

Few studies have examined the genetic population structure of vector-borne microparasites in wildlife, making it unclear how much these systems can reveal about the movement of their associated hosts. This study examined the complex host–vector–microbe interactions in a system of bats, wingless ectoparasitic bat flies (Nycteribiidae), vector-borne microparasitic bacteria (Bartonella) and bacterial endosymbionts of flies (Enterobacterales) across an island chain in the Gulf of Guinea, West Africa. Limited population structure was found in bat flies and Enterobacterales symbionts compared to that of their hosts. Significant isolation by distance was observed in the dissimilarity of Bartonella communities detected in flies from sampled populations of Eidolon helvum bats. These patterns indicate that, while genetic dispersal of bats between islands is limited, some non-reproductive movements may lead to the dispersal of ectoparasites and associated microbes. This study deepens our knowledge of the phylogeography of African fruit bats, their ectoparasites and associated bacteria. The results presented could inform models of pathogen transmission in these bat populations and increase our theoretical understanding of community ecology in host–microbe systems.

Effects of culling vampire bats on the spatial spread and spillover of rabies virus.

Controlling pathogen circulation in wildlife reservoirs is notoriously challenging. In Latin America, vampire bats have been culled for decades in hopes of mitigating lethal rabies infections in humans and livestock. Whether culls reduce or exacerbate rabies transmission remains controversial. Using Bayesian state-space models, we show that a 2-year, spatially extensive bat cull in an area of exceptional rabies incidence in Peru failed to reduce spillover to livestock, despite reducing bat population density. Viral whole genome sequencing and phylogeographic analyses further demonstrated that culling before virus arrival slowed viral spatial spread, but reactive culling accelerated spread, suggesting that culling-induced changes in bat dispersal promoted viral invasions. Our findings question the core assumptions of density-dependent transmission and localized viral maintenance that underlie culling bats as a rabies prevention strategy and provide an epidemiological and evolutionary framework to understand the outcomes of interventions in complex wildlife disease systems.

Animal seed dispersal recovery during passive restoration in a forested landscape.

Seed dispersal by animals is key for restoration of tropical forests because it maintains plant diversity and accelerates community turnover. Therefore, changes in seed dispersal during forest restoration can indicate the recovery of species interactions, and yet these changes are rarely considered in forest restoration planning. In this study, we examined shifts in the importance of different seed dispersal modes during passive restoration in a tropical chronosequence spanning more than 100 years, by modelling the proportion of trees dispersed by bats, small birds, large birds, flightless mammals and abiotic means as a function of forest age. Contrary to expectations, tree species dispersed by flightless mammals dominated after 20 years of regeneration, and tree richness and abundance dispersed by each mode mostly recovered to old growth levels between 40 and 70 years post-abandonment. Seed dispersal by small birds declined over time during regeneration, while bat dispersal played a minor role throughout all stages of succession. Results suggest that proximity to old growth forests, coupled with low hunting, explained the prevalence of seed dispersal by animals, especially by flightless mammals at this site. We suggest that aspects of seed dispersal should be monitored when restoring forest ecosystems to evaluate the reestablishment of species interactions. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.

Origin and evolution of the Micronesian biota: Insights from molecular phylogenies and biogeography reveal long‐distance dispersal scenarios and founder‐event speciation

AbstractMicronesian islands taxa show high endemism rates, but very little is known about their biogeographical histories. The lack of systematic biogeography is mainly due to insufficient phylogenetic research in Micronesia. With the recent increase in published molecular biogeographic data, we were able to, for the first time, answer fundamental biogeography questions by reviewing and analyzing numerous geological, ecological, and evolutionary studies. This review, in addition to providing an overview of Micronesian geological history, confirmed the importance of long‐distance dispersal mechanisms and founder‐event speciation, and morphological and physiological adaptations of plant propagules to cross vast stretches of ocean by wind, ocean currents, bird, or bat dispersal. These adaptations to habitat and geological features, including reef types, determined colonization success as well as inland dispersal and speciation mechanisms. We further identified the source areas of the Micronesian biota and reconstructed historical dispersal scenarios: a dominant Austro‐Melanesian dispersal scenario, an Indo‐Malaysian connecting to the Austro‐Melanesian dispersal scenario, and a Neotropical American and an African dispersal scenario toward Micronesia. Most generic origins were estimated between the Eocene and the Miocene and dispersed to Micronesia between the Miocene and the Pleistocene.

Presence of Light Pollution as a Latent Anthropogenic Influence of Bat Dispersal in Mindanao, Philippines

Background/Objectives: The study aimed to determine the extent of the presence of light pollution dispersal in Mindanao, Philippines that influences bat dispersal. Methods/Statistical analysis: Satellite imagery and radiance data (10-9 W/cm2*sr) from Visible Infrared Imaging Radiometer Suite (VIIRS) were processed using different python codes to identify the pixel count as the extent of light pollution radiance in Mindanao, Philippines from 2012 to 2019. The VIIRS was set at an overlay of 60 transparency levels thru Sky Quality Meter (SQM) at 85 transparency levels for a hybrid base map at an altitude of 100 km to cover the island of Mindanao. Findings: The increase and spread of pixel count as light pollution in the region from 2012 to 2019 have shown significant expanse in the region. Major cities were found to be predominating evidence of light pollution as it stretches from town to town with intensifying pixel counts year by year. Having a strong positive linear relationship as identified R2 value and the increase of pixel counts throughout the parameters of the study is also anticipated that the site shows possible progress towards the community. It shows the increasing radiance and the extreme dispersion on the amount of light being emitted from the ground is critical towards bats dispersion throughout the region. Novelty/Applications: This study fosters evidence the increasing light pollution in a bat-prone region might cause possible bat dispersal related to BtCoV and/or any disease-carrying species present in Mindanao, Philippines. Keywords: Light Pollution; Bat Dispersal; Mindanao; Philippines

Using Stochastic Modeling to Predict the Effect of Culling and Colony Dispersal of Bats on Zoonotic Viral Epidemics.

Frequent outbreaks of emerging infectious diseases originating from wild animals have highlighted the necessity of managing wildlife populations to prevent zoonotic spillover, and the appropriate development of management protocols required attention on gaining a better understanding of viral dynamics in wild animal populations. In east Australia, there have been outbreaks of Hendra virus (HeV) infection in horses and humans following spillover from the virus's reservoir hosts, flying foxes (family Pteropodidae), and bat culling and colony dispersal have been proposed as appropriate management strategies. A key factor relating to flying fox population structure that influences HeV dynamics is that these bats form metapopulations, and consequently, to assess this factor, we designed an epidemic dynamics model of HeV transmission, focusing on bat metapopulation dynamics. Specifically, using flying fox movement data, we stochastically simulated models for a hypothetical metapopulation of flying foxes to examine the impact of metapopulation-related parameters, and subsequently simulated probable scenarios of culling and colony dispersal to estimate their effects on the probability of epidemic occurrence. Modeling of the hypothetical metapopulation revealed that a reduction in the number of large-sized colonies would lead to an increase in the probability of epidemic occurrence within the bat population, whereas the strong spatial coupling among colonies was found to dilute the effects of altering the number of colonies and the number of bats in each colony through culling or colony dispersal of bats on the probability that an epidemic within the bat population would occur. Culling and colony dispersal scenarios showed no significantly beneficial effect with respect to reducing the probability of an HeV epidemic occurring in flying foxes, and may indeed prove counterproductive. In conclusion, the modeling results indicate that bat culling and colony dispersal may not be an effective strategy to control HeV epidemics.

Communicating risk in human-wildlife interactions: How stories and images move minds.

Effectively communicating risk is critical to reducing conflict in human-wildlife interactions. Using a survey experiment fielded in the midst of contentious public debate over flying fox management in urban and suburban areas of Australia, we find that stories with characters (i.e., narratives) are more effective than descriptive information at mobilizing support for different forms of bat management, including legal protection, relocation, and habitat restoration. We use conditional process analysis to show that narratives, particularly with accompanying images, are effective because they cause emotional reactions that influence risk perception, which in turn drives public opinion about strategies for risk mitigation. We find that prior attitudes towards bats matter in how narrative messages are received, in particular in how strongly they generate shifts in affective response, risk perception, and public opinion. Our results suggest that those with warm prior attitudes towards bats report greater support for bat dispersal when they perceive impacts from bats to be more likely, while those with cool priors report greater support for bat protection when they perceive impacts from bats to be more positive, revealing 1) potential opportunities for targeted messaging to boost public buy-in of proposals to manage risks associated with human-wildlife interactions, and 2) potential vulnerabilities to disinformation regarding risk.

Understanding the relationship between climatic niches and dispersal through the lens of bat wing morphology

AbstractClimate, an important dimension within the classical Hutchinsonian niche concept, represents abiotic variables that influence species distributions. As dispersal allows species to move and colonize new regions with distinct climates, the role of dispersal traits in determining the occupation of particular climatic conditions is hypothesized to be important in climatic niche determination. I test this hypothesis by investigating the effects of interspecific variation in bat dispersal abilities due to wing morphology on species climatic niches. For 74 phyllostomid bat species, I collected their niche positions (i.e. mean value of occupied climatic conditions) along the climatic space as defined by phylogenetic principal components, as well as wing variables related to flight performance and aerodynamics. To test how wing variables are related to species positions along climatic niche axes, I used a framework of phylogenetic regressions and model selection by information theory. I found that wing morphology has an important and positive influence on bat species niche positions in the climatic space. Species with increased relative wing loading have better flight performance which likely allowed them to overcome geographical barriers to dispersal in order to colonize areas with distinct climatic regimes, thus influencing their climatic niche configurations. My results reconcile the morphological role bat wings have on local habitat use with their effects on dispersal and their importance in shaping climatic niches at broad scales. Overall, my findings reinforce the roles of dispersal and complementary life‐history traits in determining species climatic niches. These results imply that traits linked to tracking suitable habitats may be important for adapting to climate change.

Landscape changes decrease genetic diversity in the Pallas’ long-tongued bat

Species with high mobility may have low genetic differentiation among populations due to historical long-distance dispersal, but recent studies show that bat dispersal may be affected by habitat loss and fragmentation. Here, we analyze the effects of landscape contemporary changes and dynamics in paleodistribution during the Quaternary on genetic diversity and differentiation in the Pallas’ long-tongued bat, Glossophaga soricina. We sampled 18 populations in landscapes with different land cover, and used nine microsatellite loci and the sequence of a fragment of the mitochondrial gene cytochrome b (CYB) to obtain genetic data. We performed ecological niche modelling and used general linear mixed models and optimization of multiple resistance surfaces to analyze how landscape structure and climatic suitability affect genetic diversity and differentiation. Our results show that the conversion of natural vegetation, such as forests and savannas, to agriculture, pastures or urban matrices (unsuitable habitats) decreases genetic diversity and increases inbreeding, but has no effect on genetic differentiation among populations, that was likely affected by spatial distance. Our findings point to the importance of maintenance of large areas of natural vegetation remnants to conserve genetic diversity of G. soricina, an important bat pollinator in the Neotropics.

Bat dispersal of fern spores in New Zealand

Bat dispersal of fern spores in New Zealand

Landscape structure and ecology influence the spread of a bat fungal disease

Abstract White‐nose syndrome (WNS), affecting multiple North American bat species during the hibernation period, is a highly pathogenic disease caused by the psychrophilic fungus Pseudogymnoascus destructans (Pd). Because the fungal pathogen persists in the hibernation site environment independently of the hosts, previous theory on spatial disease dynamics cannot predict WNS epidemics. However, the ability to understand factors contributing to the spread of white‐nose syndrome (WNS) in North America is crucial to the management of infected and susceptible bat populations as well as the conservation of threatened and endangered bat species. Utilizing recent theory on environmental opportunistic pathogens, we modelled the effect of (a) landscape clustering, (b) environmental conditions in hibernacula and (c) microbial competition on the spread of WNS. We used available, already published data to construct and parameterize our model, which takes into account the spatial distribution of hibernation sites, temperature conditions in both the outside ambient and hibernation site environment, bat population dynamics, dispersal and infection by the pathogen, which also has its host‐independent dynamics with the environment. We also consider the effect of outside‐host competition between the pathogen and other micro‐organisms on spatial disease dynamics. Our model suggests that pathogen loads accumulate in poorly connected hibernacula at short host dispersal, which can help found the epidemic. In contrast, invasion of the landscape is most successful at long host dispersal distances, with homogenous hibernation site distribution and heterogeneous between‐hibernation site temperatures. Also, increasing the mean temperature across hibernacula increases fungal growth rate, leading to higher disease prevalence and faster invasion rate. Increasing spatial heterogeneity in hibernaculum temperatures results in the formation of disease hotspots in warmer hibernacula, facilitating more effective spread of the disease in the landscape. Cold‐adapted competing microbes can prevent invasion, and therefore, overwintering in cold hibernacula increases probability of host survival. Sites that were suboptimal for overwintering prior to WNS may have importance in preventing local extirpations. Although the model is tailored for WNS, due to pressing need for results that can assist in planning conservation measures, these novel results can be broadly applied to other environmentally transmitted diseases. A plain language summary is available for this article.

A stem bat (Chiroptera: Palaeochiropterygidae) from the late middle Eocene of northern Anatolia: implications for the dispersal and palaeobiology of early bats

Fragmentary remains of an Eocene bat are described from the middle Eocene Luluk Member of the Uzuncarsidere Formation on the Pontide terrane, in what is now north-central Anatolia. The new taxon most closely resembles the palaeochiropterygids Lapichiropteryx and Stehlinia in terms of its known dental morphology, and it is referred to the stem chiropteran family Palaeochiropterygidae on this basis. Geological and palaeontological data indicate that the Pontide terrane was an island situated along the northern margin of Neotethys during the middle Eocene. The presence of a late-surviving stem chiropteran in an island context potentially illuminates dispersal patterns and capabilities among the earliest bats, which already enjoyed a nearly global distribution by the early Eocene. Other palaeochiropterygids for which postcranial material is known share little in common with extant bats that are capable of long-range dispersal across open water. The new Turkish bat taxon is consistent with a hypothetical dispersal corridor between Western Europe and India via islands on the northern margin of Neotethys and suggests a larger range of skeletal and locomotor variation within Palaeochiropterygidae than is currently recognised.

Terrestrial Behavior and Trackway Morphology of Neotropical Bats

Bats (Chiroptera) are unique among flying animals in being the only mammal capable of powered flight and the only extant group that is quadrupedal. Extant bats demonstrate varying levels of terrestrial competency, however, the terrestrial abilities of many groups are unknown. Here we examine the terrestrial ability and resultant traces produced by bats belonging to the families Phyllostomidae and Emballonuridae. Five different subfamilies of phyllostomids and the emballonurid Saccopteryx bilineata were video recorded and analyzed for their terrestrial locomotor behaviors over a sand medium, with resultant tracks and trackways cast and measured. Behaviors and traces were compared to morphological criteria previously hypothesized to constrain terrestrial abilities of bats. Type 1 species (presumed poor walkers) generally performed only a breaststrokelike crawl and nonambulatory searching behavior, whereas the terrestrially adept Type 3 Desmodus rotundus performed a diagonal sequence walk and bound. Behaviors and traces produced by the intermediate Type 2 S. bilineata were indistinguishable from those of the Type 1 bats. Results only partially support the hypothesized morphological basis for terrestrial ability in bats and indicate that ecological differences or as yet unrecognized morphological variations may be the cause of behavioral variations in bats of the same morphotype. This research fills gaps in our knowledge of the terrestrial behaviors of nondesmodontine phyllostomid bats, and is the first study to examine the terrestrial behaviors of any species of emballonurid. Results of this research can be used for comparison to potential bat traces recorded in the geologic record, allowing for a better understanding of bat evolution and dispersal patterns.

Assessing the potential impacts of a changing climate on the distribution of a rabies virus vector.

Common vampire bats (Desmodus rotundus) occur throughout much of South America to northern México. Vampire bats have not been documented in recent history in the United States, but have been documented within about 50 km of the U.S. state of Texas. Vampire bats feed regularly on the blood of mammals and can transmit rabies virus to native species and livestock, causing impacts on the health of prey. Thus cattle producers, wildlife management agencies, and other stakeholders have expressed concerns about whether vampire bats might spread into the southern United States. On the other hand, concerns about vampire-borne rabies can also result in wanton destruction at bat roosts in areas occupied by vampire bats, but also in areas not known to be occupied by this species. This can in turn negatively affect some bat roosts, populations, and species that are of conservation concern, including vampire bats. To better understand the current and possible future distribution of vampire bats in North America and help mitigate future cattle management problems, we used 7,094 vampire bat occurrence records from North America and species distribution modeling (SDM) to map the potential distribution of vampire bats in North America under current and future climate change scenarios. We analysed and mapped the potential distribution of this species using 5 approaches to species distribution modeling: logistic regression, multivariate adaptive regression splines, boosted regression trees, random forest, and maximum entropy. We then projected these models into 17 “worst-case” future climate scenarios for year 2070 to generate hypotheses about how the vampire bat distribution in North America might change in the future. Of the variables used in this analysis, minimum temperature of the coldest month had the highest variable importance using all 5 SDM approaches. These results suggest two potential near-future routes of vampire bat dispersal into the U.S., one via southern Texas, and a second into southern Florida. Some of our SDM models support the hypothesis that suitable habitat for vampire bats may currently exist in parts of the México–U.S. borderlands, including extreme southern portions of Texas, as well as in southern Florida. However, this analysis also suggests that extensive expansion into the south-eastern and south-western U.S. over the coming ~60 years appears unlikely.

Using sutures to attach miniature tracking tags to small bats for multimonth movement and behavioral studies.

Determining the detailed movements of individual animals often requires them to carry tracking devices, but tracking broad-scale movement of small bats (<30 g) has been limited by transmitter technology and long-term attachment methods. This limitation inhibits our understanding of bat dispersal and migration, particularly in the context of emerging conservation issues such as fatalities at wind turbines and diseases. We tested a novel method of attaching lightweight global positioning system (GPS) tags and geolocating data loggers to small bats. We used monofilament, synthetic, absorbable sutures to secure GPS tags and data loggers to the skin of anesthetized big brown bats (Eptesicus fuscus) in Colorado and hoary bats (Lasiurus cinereus) in California. GPS tags and data loggers were sutured to 17 bats in this study. Three tagged bats were recaptured 7 months after initial deployment, with tags still attached; none of these bats showed ill effects from the tag. No severe injuries were apparent upon recapture of 6 additional bats that carried tags up to 26 days after attachment; however, one of the bats exhibited skin chafing. Use of absorbable sutures to affix small tracking devices seems to be a safe, effective method for studying movements of bats over multiple months, although additional testing is warranted. This new attachment method has the potential to quickly advance our understanding of small bats, particularly as more sophisticated miniature tracking devices (e.g., satellite tags) become available.

Resolving the roles of immunity, pathogenesis, and immigration for rabies persistence in vampire bats.

Bats are important reservoirs for emerging infectious diseases, yet the mechanisms that allow highly virulent pathogens to persist within bat populations remain obscure. In Latin America, vampire-bat-transmitted rabies virus represents a key example of how such uncertainty can impede efforts to prevent cross-species transmission. Despite decades of agricultural and human health losses, control efforts have had limited success. To establish persistence mechanisms of vampire-bat-transmitted rabies virus in Latin America, we use data from a spatially replicated, longitudinal field study of vampire bats in Peru to parameterize a series of mechanistic transmission models. We find that single-colony persistence cannot occur. Instead, dispersal of bats between colonies, combined with a high frequency of immunizing nonlethal infections, is necessary to maintain rabies virus at levels consistent with field observations. Simulations show that the strong spatial component to transmission dynamics could explain the failure of bat culls to eliminate rabies and suggests that geographic coordination of control efforts might reduce transmission to humans and domestic animals. These findings offer spatial dynamics as a mechanism for rabies persistence in bats that might be important for the understanding and control of other bat-borne pathogens.

Population Genetics and Bat Rabies: A Case Study ofEptesicus serotinusin Poland

The serotine bat, Eptesicus serotinus is the most frequently rabies-infected (European bat lyssavirus 1-type, EBLV-1) bat species in Europe. To confirm Lyssavirus infection of this bat in Poland, we tested for the presence of rabies virus RNA from oropharyngeal swabs using RT-PCR. There was a 0.9% (two out of 212 individuals) level of infection within the overall population of serotine bats studied. However, an appreciation of the potential for pathogen transmission and disease risk requires an understanding of the dispersal of the primary host, and any large-scale geographic barriers that may impede gene flow. Thus, we also studied the patterns of bat dispersal via population genetics using nuclear (seven microsatellite loci) and mitochondrial (mtDNA control region) markers, examined in 12 subpopulations distributed across the country. Molecular analyses of microsatellite loci indicated high genetic diversity at all sites (heterozygosity observed, H o = 0.53–0.78), and extremely weak genetic structure in the Polish population of the species. The overall F ST was 0.012 (95% confidence interval: 0.006–0.020), and pairwise values ranged from 0.00 to 0.05. Only 22% of individuals were assigned to the subpopulation from which they were sampled. The Bayesian approach implemented in STRUCTURE also confirmed that all examined subpopulations should be treated as a single group, indicating a high level of gene flow. There was some evidence for female philopatry (genetic differentiation was greater in maternally-inherited mtDNA than nuclear DNA) and male-biased dispersal, e.g., H o and the variance of mean assignment were significantly higher in males than in females. Twelve individuals (seven females and five males) were identified as potential first generation migrants. Their migration routes ranged from 60–283 km in females ( ± SE = 177.9 ± 29.37) to 27–385 km in males (206.4 ± 58.95); surprisingly, no sexual differences were observed and this finding suggests that female-mediated gene flow may occur. MtDNA also produced a strong genetic signal for the demographic expansion (Fu's F S statistics, F S = -26.30, P < 0.01 and a star-shaped haplotype network), which took place roughly 33,000 years BP, i.e., before the Last Glacial Maximum. The genetic uniformity of the Polish population implies that there is no migration barrier to EBLV-1, at least within the country, and the potential threat of rabies virus spreading via migration of infected animals may be higher than previously thought.

Anthropogenic Roost Switching and Rabies Virus Dynamics in House-Roosting Big Brown Bats

Big brown bats (Eptesicus fuscus) are the most commonly encountered rabid bat in North America and represent an important source of wildlife rabies epizootics. Urban and suburban colonies of E. fuscus are often evicted from their roosts in houses, with poorly understood consequences for bat dispersal, population dynamics, and rabies virus transmission. We combined radiotelemetry and mark-recapture of E. fuscus with enhanced surveillance to understand the frequency of rabies virus exposure in house-roosting bats and to assess the potential for behavioral responses of eviction to exacerbate viral transmission. Serology demonstrated the circulation of rabies virus in nearly all sites, with an overall seroprevalence of 12%, but no bats were excreting rabies virus at the time of capture. Bats that were excluded from roosts relocated to houses <1 km from the original roost. However, behavioral responses to eviction differed, with bats switching repeatedly among new roosts in 1 site, but fusing with a neighboring colony in another. These findings confirm the circulation of rabies virus in E. fuscus that live in close contact with humans and companion animals, suggest mechanisms through which anthropogenic disturbance of bats might influence pathogen transmission, and highlight simple strategies to balance conservation and public health priorities.

Seed Dispersal in the Dark: Shedding Light on the Role of Fruit Bats in Africa

AbstractIn spite of their recognized importance as seed dispersers in other parts of the tropics, seed dispersal by fruit bats has received scant research attention in Africa. To evaluate the role of African fruit bats in seed dispersal, we studied fruits and seeds below 480 bat feeding roosts in the East Usambara Mountains of Tanzania. We compared these findings to those reported in other African localities to place our results in a broader context. We found 49 plant species dispersed by bats: 28 species, 18 genera, and one family are novel reports of bat dispersal in Africa. Approximately 20 percent of the submontane tree flora of the East Usambaras is bat‐dispersed, including both widespread and endemic trees. African fruit bats are important seed dispersers at our study site because they move seeds of dozens of species tens or hundreds of meters, even seeds that are too large to ingest (greater than 5 mm in length). Fruit bats are likely important seed dispersers in other Afrotropical forests, as bats elsewhere in Africa are known to consume 20 genera and 16 species of plants reported here. Insights from studying remains under bat feeding roosts offer a simple method to further document and substantially increase our understanding of the role of African fruit bats in seed dispersal.

Migration and dispersal patterns of bats and their influence on genetic structure

Abstract Bats are important ecosystems service providers, make a significant contribution to biodiversity and can be important pests and disease vectors. In spite of this, information on their migration and dispersal patterns is limited. In temperate bats, migration is most evident in females. This reflects seasonal differences in their habitat requirements, and the fact that seasonally suitable sites can be geographically distant. Tropical bats mainly migrate to track variation in food availability. Little direct information is available on the patterns and drivers of bat dispersal, although drivers may include mate competition and inbreeding avoidance. In many temperate species, differential energy requirements and local resource competition among the sexes drive sexual segregation in the summer: females remain philopatric to their natal region, and frequently to their natal colony, while males disperse. In contrast, many tropical Pteropodidae form single‐male/multi‐female groups in which local resource defence contributes to female‐biased or all‐offspring dispersal from the natal site. Population genetic studies are the most common source of evidence used to infer the spatial dynamics of bats. As expected, migratory species tend to have less genetically structured populations over large geographical scales due to mating outside of breeding areas, weak migratory connectivity and long‐distance movements. In contrast and as expected, populations of sedentary species tend to be more differentiated at smaller geographical scales. Despite this general pattern, a range of factors, including historical events, dispersal capabilities, and behavioural, ecological and geographical barriers, are implicated in the genetic partitioning of bat populations, irrespective of movement patterns. These factors limit the study of bat movements using only genetic methods. Combining population genetics with other methods, such as mark–recapture, tracking or stable isotope analysis, should provide more insight into the movements of these ecologically and economically important species.