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Wildlife conservation involves making management decisions with incomplete knowledge of ecological relationships. Efforts to augment foraging resources for the endangered Mexican long‐nosed bat (Leptonycteris nivalis) are progressing despite limited knowledge about the species' foraging behavior and requirements. This study aimed to understand L. nivalis responses to floral resource availability, focusing on individual agave‐ and local‐scale characteristics influencing visitation rates to flowering agaves. We observed bat visitation at 62 flowering agaves around two roosts in northeast Mexico on 46 nights in the summers of 2017 and 2018. We found visitation rate had positive relationships with two agave‐scale characteristics: the number of umbels with open flowers and the lower vertical position on the stalk of those umbels (i.e., earlier phenological stages of flowering). However, these factors exhibited strong negative interaction: with few umbels with open flowers, the position of flowering umbels had little effect on visitation rate, but when umbels with open flowers were abundant, visitation rate was more strongly related to the lower flowering umbel position. We also found relationships between visitation rate and two local‐scale characteristics: negative for the density of flowering conspecifics within 30 m of the focal agave and positive for the density of dead standing agave stalks within 30 m. Our findings suggest opportunities to augment foraging resources for L. nivalis in ways that are consistent with their foraging behavior, including: increasing the supply of simultaneously blooming flowers by planting agave species that tend to have more umbels with simultaneously open flowers; planting multiple species of agaves with different flowering times to increase the availability of agaves with open flowers on lower‐positioned umbels throughout the period when bats are present in the region; planting agaves in clusters; and keeping dead standing agave stalks on the landscape. Our study points to useful management strategies that can be implemented and monitored as part of an adaptive management approach to aid in conservation efforts. [ABSTRACT FROM AUTHOR]

The movement of individuals between roosts allows gene flow and influences the spatial distribution, dynamics, and genetic structure of populations. The objectives of this study were to describe the patterns of movement of the bats Mormoops megalophylla, Pteronotus fulvus, and Pteronotus mesoamericanus, between a mine (La Mina) and two caves (El Apanguito and Cerro Huatulco) and explore some drivers for the movements in Oaxaca, México using capture-recapture methods. From July 2016 to June 2017, we captured 5082 individuals (2369 P. fulvus, 1868 P. mesoamericanus, and 845 M. megalophylla). We obtained 292 recaptures, including 57 recaptures represented inter-roost movements (34 by P. fulvus, 18 by P. mesoamericanus, and 5 by M. megalophylla). Brownie's Multistate model showed that the movements among roosts were species-specific and were determined only by the roost occupied before capture for P. mesoamericanus, by the roosts used before and after capture for P. fulvus, or only by seasonality for M. megalophylla. The results showed that the reproductive condition could have influenced the movements between roosts in the three mormoopids, mainly due to the formation of maternity colonies of P. mesoamericanus and P. fulvus in the El Apanguito cave and exclusive colonies of M. megalophylla males in Cerro Huatulco. Due to the importance of the reproductive events that occur in the roosts studied, we suggest that the three roosts should be considered as part of the group of Important Sites for the Conservation of Bats in the state of Oaxaca. [ABSTRACT FROM AUTHOR]

Aim: Understanding speciation mechanisms requires disentangling processes that promote and erode population‐level divergence. Three hypotheses are raised that contemporary population structure is mainly shaped by refugial isolation, gene flow or both. Testing these hypotheses requires range‐wide phylogeography and integrative analyses across scales. Here we aimed to (1) re‐estimate the previously unresolved nuclear divergence within a widespread bat; (2) test the above three phylogeographical hypotheses and (3) inform conservation management under climatic change. Location: North America including the Caribbean. Taxon: The big brown bat (Eptesicus fuscus). Methods: We collected range‐wide samples and genome‐wide markers using restriction site‐associated DNA sequencing. Population structure was analysed by clustering methods and spatial estimations. Nuclear phylogeographical divergence was estimated using tree methods (concatenation and coalescence) and network analyses (TreeMix). Phylogeographical hypotheses were tested by comparing alternative evolutionary scenarios using demographic modelling. Species distribution modelling was used to help identify Pleistocene refugia and predict future range shifts under climatic change. Results: We identified three populations in the Caribbean, eastern and western North America. The western population further split into three phylogeographical clades: Pacific, southwestern North America and Mexico. Discordance among mitochondrial and nuclear topologies reflected strong impacts of gene flow without sex bias. Demographic modelling supported scenarios of historical isolation followed by secondary gene flow and estimated Holocene divergence times. Species distribution was essentially continuous during glaciation with possible regional isolation, and northward range shifts were predicted under future climatic change. Main Conclusions: Contemporary population divergence of big brown bats was shaped by both historical isolation and secondary gene flow, supporting the third phylogeographical hypothesis. While climatic change likely triggered initial divergence, ongoing gene flow has largely impacted the dynamic within‐species evolution and generated population divergence without speciation. [ABSTRACT FROM AUTHOR]

It has been suggested that Lasiurus cinereus cinereus migrates from summer roosts at higher latitudes to the coastal regions and southern latitudes in the United States and Mexico to overwinter, where little is known about its winter ecology. We found a hoary bat in a shrub in a conifer forest at high elevation in central Mexico in November 2019. We installed a camera trap and recorded it was hibernating for at least 12.7 days. Our record is by far the most southern hibernation location of tree bats in North America and it shows L. cinereus is capable of hibernating in a non-typical roost. We also open the possibility that camera traps may provide an additional, practical, and easy-to-use tool to study bat hibernation. Our finding expands the ultimate questions of why and where hoary bats decide to hibernate, migrate or both. [ABSTRACT FROM AUTHOR]

Wind energy development causes bat fatalities. Despite emphasis on understanding and reducing these impacts, few data are available for the southwest region of the United States and northern Mexico. We monitored bat fatalities for a full year (March 2017–March 2018) at a wind energy facility in south Texas near the United States–Mexico border. We established search plots of 100-m radius at eight randomly selected turbines (of 255) and searched the roads and pads at an additional 92 turbines. We conducted weekly searches from spring through fall and bimonthly during winter. We used GenEst (Gen eralized Mortality Est imator) to estimate bat fatalities corrected for searcher efficiency, carcass removal, and density-weighted proportion of area searched. We found 205 bats during standardized searches, the majority of which were Brazilian free-tailed bats (Tadarida brasiliensis , 76%). The corrected fatality estimates were 16 bats/megawatt/year (95% confidence interval [ CI ]: 12 – 30 bats/megawatt/year) across all species. Species composition at our site is similar to that of northern Mexico, an area of expanding wind energy development with no published studies. [ABSTRACT FROM AUTHOR]

A large part of the natural vegetation in the tropics has been replaced by pastures and crop fields. To evaluate the value of mango orchards in the conservation of phyllostomid bats in a fragmented, heterogeneous landscape in Veracruz, Mexico we compared species richness, total abundance, dominance, evenness and abundance per feeding guild of bats in mango polycultures, mango monocultures and in semi-deciduous seasonal forest. Using mist nets at ground level, we captured 882 phyllostomid bats belonging to 17 species. Bat species richness was similar between the mango orchards and the forest, but the number of bats was significantly higher in mango polycultures, followed by mango monocultures and the forest. The frugivore guild was the most numerous in the mango orchards. Sanguivores were notably more numerous in the forest. Our results suggest that both types of mango orchards are different from the forest, since they are characterized by differences in bat species composition and feeding guild. We conclude that mango agroecosystems, when small in size and close to the forest, are important in the conservation of bats; it is there where bats are abundant and maintain a level of species richness similar to that of the original vegetation. [ABSTRACT FROM AUTHOR]

Aim: The Mexican long‐tongued bat (Choeronycteris mexicana), Mexican long‐nosed bat (Leptonycteris nivalis) and lesser long‐nosed bat (Leptonycteris yerbabuenae) (Phyllostomidae: Glossophaginae) undertake long‐distance migrations from south‐central Mexico to the south‐western United States. It is proposed that these bats migrate along a nectar corridor of columnar cacti and Agave species, but this has not been tested with independent data and the spatiotemporal nature of this relationship is poorly understood. Our goal was to test this nectar corridor hypothesis and determine the relative importance of food plant and abiotic variables to the distribution and seasonal movements of these migratory nectarivores. Location: Mexico and the south‐western United States. Methods: We generated species distribution models (SDMs) of documented food plants for these bats. We then created SDMs for each bat following a model selection approach, using food plant and abiotic predictor variables. We modelled migration pathways for C. mexicana and L. yerbabuenae using circuit theory and seasonal SDMs based on seasonally available food plants. Main conclusions: Food plants were more important than climatic and topographic variables in shaping the distribution of these bats. The most important predictors of distribution were Agave, columnar cacti and species richness of food plants. Species richness of food plants was the most consistently important variable, but the components of this diversity varied by bat species: Choeronycteris mexicana was influenced by Agave and cacti; Leptonycteris nivalis was influenced solely by Agave; Leptonycteris yerbabuenae was influenced more generally by cacti, Agave and C3 plants. Migration models for C. mexicana and L. yerbabuenae provided independent support for the nectar corridor hypothesis and indicate shifts in relative importance of specific food plants throughout the year. These results suggest that conservation of these bats should focus more broadly on management for species richness of food plants, especially in tropical dry forests. [ABSTRACT FROM AUTHOR]

Bats face an unprecedented array of threats in the early 21st century, from traditional concerns such as habitat loss, to white nose syndrome and collisions with wind turbines. These growing challenges arise when the National Wildlife Refuge System, a system of public lands and waters that provides habitat for nearly every bat species in North America north of Mexico, is beginning its first revision cycle for its management plans, known as Comprehensive Conservation Plans. The U.S. Fish and Wildlife Service is thus uniquely positioned to assess its current contribution to sustaining viable populations of bats in the United States and incorporate those findings into the biological objectives that will guide Refuge management for the next 15 y. We present a review of the degree to which the first generation of Comprehensive Conservation Plans addresses bat conservation, and we provide recommendations to guide managers, planners, and partners in the development of the second generation of these Comprehensive Conservation Plans. [ABSTRACT FROM AUTHOR]