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The Mexican Long-nosed bat (Leptonycteris nivalis) is the largest nectarivorous species in the New World, and one of three migratory nectarivores in Mexico. It is considered an ‘Endangered Species’ under the U.S. Endangered Species Act and ‘Threatened’ by the Mexican Federal List of Endangered Species. In 1994, a Recovery Plan was developed by the USFWS with the participation of Mexican and American researchers, and the most urgent actions to ensure the species protection were identified. Locating and protecting roosts are among the most urgent tasks recognized. With this study, we aimed to identify the most suitable areas potentially holding additional mating roosts of Leptonycteris nivalis, and we conducted surveys of these areas to confirm its presence, and to assess the reproductive state of individuals. We used Maxent, the Genetic Algorithm for Rule-set Production (GARP), and Bioclim algorithms to generate an agreement map of the potential distribution of additional mating roosts, and we implemented a Euclidian multidimensional distances analysis to identify ecologically similar regions to “La Cueva del Diablo”, the only mating roost known for the species. We identified suitable areas in the states of Morelos, Puebla and the State of Mexico. We visited seventeen caves distributed in ten different localities in these areas. For two consecutive years, we found the species in a cave called: “La Cueva de los Coyotes”, located in the State of Mexico, where we captured eighteen individuals, including a pregnant female. The location of an unknown roost so far, occupied by individuals of L. nivalis, and among them a pregnant female, allows us to reflect about the reproductive dynamics of the species. In that sense, reproductive populations may be splitting into smaller colonies to mate, other than “La Cueva del Diablo”, or pregnant females might me moving to additional and nearby roosts to spend the rest of the winter season. Using these tools and further refinements we may be able to locate additional mating roosts, thus, providing more possibilities for the application of conservation measures for the protection of the species.

Baird’s tapir (Tapirella bairdii), white-lipped peccary (Tayassu pecari), and collared peccary (Dicotyles tajacu) sympatrically occur in the Lacandon Forest of Chiapas, México. These species contribute to maintain ecosystem dynamics through herbivory, seed dispersal, and seed predation, constituting important prey for large carnivores and hunters. We analyzed activity patterns and habitat use of the three focal species to assess the degree of temporal and spatial habitat segregation among them in Montes Azules Biosphere Reserve (REBIMA) and surrounding communities. Between February and October 2015 we deployed camera-traps during 8,463 camera-trap days to estimate the presence and activity of tapirs and peccaries in two habitat types: “conserved” (REBIMA), and “transformed” (community forests; AFC). Habitat use and activity patterns of tapirs and peccaries were assessed through logistic regression models. We found that Baird’s tapir was almost exclusively nocturnal with a trend towards crepuscular activity, while both peccary species were diurnal, therefore showing a high daily temporal segregation from the tapir. Both peccary species were similarly active in the two study sites, while tapirs were more active in continuous forest within the protected area. The occurrence of tapirs and white-lipped peccaries depended on the presence and proximity of water sources and roads. Our results suggest that spatial segregation of the habitat allows coexistence of both peccary species in the study area. AFC have potential for maintaining populations of tapirs and peccaries in the Lacandon Forest. Conserving these forests by local communities is essential to ensure the persistence of these mammals.

We evaluated the morphometric variation of wing mite Periglischrus paracaligus Herrin and Tipton, along with the distribution of their host Leptonycteris yerbabuenae Martinez and Villa, in Mexico. A total of 115 female and 96 male specimens of P. paracaligus were used to conduct linear and geometric morphometric analyses. We assessed the influence of the geographic distribution of the migratory and nonmigratory populations of its bat host species on changes in size and shape on these parasites. Both analyses revealed high intraspecific variation in P. paracaligus, but subtle geographic differentiation. None of the approaches used identified a consistent pattern that separates unambiguously migratory from nonmigratory populations. Females presented more phenotypic variation than males and UPGMA analyses showed southern and northern colonies grouped in two distinct clades. Males on the other hand showed randomly grouped colonies with no geographic concordance. Interestingly, the most differentiated colony was the north Pacific colony of Jalisco. For both, males and females, isolation by distance (IBD) was not observed. We discuss these results as a possible scenario of contact between migratory populations located in northern Mexico with nonmigratory populations in other localities in central and southern Mexico conforming to a panmictic population along with their distribution range.

Spatial capture–recapture models have been widely used to estimate densities of species where individuals can be uniquely identified, but alternatives have been developed for estimation of densities for unmarked populations. In this study we used camera-trap records from 2018 to estimate densities of a species that does not always have individually identifiable marks, Baird's tapir Tapirus bairdii, in the Sierra Madre de Chiapas, southern Mexico. We compared the performance of the spatial capture–recapture model with spatial mark–resight and random encounter models. The density of Baird's tapir did not differ significantly between the three models. The estimate of density was highest using the random encounter model (26/100 km2, 95% CI 12–41) and lowest using the capture–recapture model (8/100 km2, 95% CI 4–16). The estimate from the spatial mark–resight model was 10/100 km2 (95% CI 8–14), which had the lowest coefficient of variation, indicating a higher precision than with the other models. Using a second set of camera-trap data, collected in 2015–2016, we created occupancy models and extrapolated density to areas with potential occupancy of Baird's tapir, to generate a population estimate for the whole Sierra Madre de Chiapas. Our findings indicate the need to strengthen, and possibly expand, the protected areas of southern Mexico and to develop an action plan to ensure the conservation of Baird's tapir.

Evaluating the degree of disturbance of any region to determine its relative importance for conservation purposes requires procedures that are relatively inexpensive and that yield accurate results fast. Because bats are abundant, diverse, and easy to sample, especially in the Neotropical rainforest, they fulfill several of the requirements of indicator species as identified in the literature. For 10 months we sampled bat communities in the Selva Lacandona in Chiapas, Mexico, at 15 sites representing five habitats. We also measured 10 variables representing vegetation structure and diversity at each site. With fuzzy-set techniques we produced a gradient classification of disturbance for the 15 sites based on the vegetation data. We explored the relationship between vegetation conditions, described as the membership degrees in the construct "fuzzy forest set" (the complementary fuzzy set of "disturbance"), and four bat community variables. Bat species richness, number of rare bat species, and the bat diversity index were positively correlated with the vegetation scores, and relative abundance of the most abundant bat species was negatively correlated with vegetation scores. A high number of phyllostomine species in a community is a good indicator of low levels of disturbance. Although a single indicator group will probably not be sufficient for decision-making processes in conservation, evaluating bat populations may be a good first step in assessing an area's conservation value, especially in rainforest regions.La evaluación del grado de perturbación de una región particular para determinar su importancia relativa para propósitos de conservación requiere que los procesos de toma de decisiones utilicen tecnologías relativamente baratas y que proporcionen resultados precisos pronto. Puesto que los murciélagos son abundantes, diversos y fáciles de muestrear, particularmente en las selvas húmedas del Neotrópico, llenan varios de los requerimientos de las especies indicadoras. Muestreamos por 10 meses comunidades de murciélagos en la Selva Lacandona de Chiapas, México, en 15 sitios representantes de cinco hábitats. También medimos 10 variables representantes de la estructura y diversidad de la vegetación en cada sitio. Mediante el uso de técnicas de conjuntos difusos produjimos una clasificación gradual de la perturbación de la vegetación para los 15 sitios. Exploramos las relaciones entre las condiciones de la vegetación, descritos como los grados de membresía en la construcción de los conjuntos difusos del bosque (el conjunto difuso complementario de la perturbación) y cuatro variables de la comunidad de murciélagos. La riqueza de especies de murciélagos, el número de especies de murciélagos raros, y el índice de diversidad de murciélagos estuvieron positivamente correlacionados con los valores de la vegetación y la abundancia relativa de la especie más abundante estuvo negativamente correlacionado con estos valores. Un alto número de especies de Phyllostominae en la comunidad es un buen indicador de bajos niveles de perturbación. Sin embrago, un solo grupo indicador probablemente no es suficiente en el proceso de toma de decisiones en conservación. La evaluación de poblaciones de murciélagos puede ser un buen primer paso en la evaluación del valor de un área para la conservación, especialmente en regiones de selva húmeda.

Bobcats (Lynx rufus) are distributed throughout North America, but bobcat densities have been well-documented primarily only for the United States. The highest known density of this species is in the southern United States, and from there their density decreases northward to southern Canada. Despite the fact thatMéxico contains about 35 % of the species range, there are no data on their abundance or density in México. The objectives of this study were to document the density of bobcats from northwestern to southern México and to understand the abundance patterns of this species. Camera traps were used in combination with capture-recapture models to estimate densities. Using the MaxEnt ecological niche model, the potential distribution of the bobcat was obtained. With an effort of 2,070 camera trap days, we obtained 41 bobcat photographs in five localities from 2005 to 2007. Our estimated bobcat densities varied from 0.05 to 0.53 bobcat/km2. Using MaxEnt, we estimated the available habitat in each site and extrapolated the density data to obtain a range of bobcat population estimates per site. The areas estimated were between 1,861 to 16,663 km2, with a population from 592 to 2,161 bobcats. Bobcat density in México is highest in the north and decreases to the south of its range. Probably the optimal habitat for this species is found in the southern United States and northern México where the highest densities of its entire distribution occur.

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.

The first record of Phyllops falcatus (Gray, 1839) in Mexico is documented from the island of Cozumel, Quintana Roo. This species is present in the Antilles, distributed in all the Cuban archipelago, Cayman Islands, and Hispaniola. It is likely that a hurricane moved these bats from Cuba to Cozumel. The Cozumel record extends the distribution more than 200 km west. Two new records from Cozumel of the bats Lasiurus ega and Molossus alvarezi are also provided.

The flat-headed myotis (Myotis planiceps) was declared extinct in 1996 but rediscovered in 2004, thus the reference to a revenant, one who came back from the dead, as it was declared extinct in 1996 but rediscovered in 2004. However, the species still faces serious extinction risk. To aid in the strategic planning and priorities for conservation, we studied roosting ecology. These bats inhabit the Chihuahuan Desert in one of the smallest distributional ranges of any mammal. Using radiotelemetry, we located 25 summer roosts, all in the skirts of dry leaves of yucca trees (Yucca carnerosana). We conclude that to roost, these bats search for clumps of tall yucca trees with a mean height of 3.93 m and mean width of skirts of 1.35 m.

Latitudinal migration increases fitness of migrants by allowing them to exploit favorable conditions in nonadjacent geographic regions. Other consequences also may follow, such as interactions with parasites. Migrants may have lower parasite prevalence and abundance than resident individuals because of their ability to abandon infested areas or due to mortality of highly infested hosts. To further understand whether variation in ectoparasite loads is influenced by migration, we investigated whether prevalence and abundance of two species of obligate ectoparasites, the wing mite Periglischrus paracaligus (Mesostigmata: Spinturnicidae) and the bat fly Nycterophilia coxata (Diptera: Streblidae, Nycterophiliinae), of the lesser long-nosed bat, Leptonycteris yerbabuenae, varied between migratory and resident populations throughout their range in Mexico. We examined the presence or absence of migratory behavior, as well as sex and reproductive status of the host because ectoparasitism differentially affects the sexes. Our results showed that the prevalence of both ectoparasites did not vary between migrant and resident females or males, but abundance of the wing mite P. paracaligus was lower in migrant females compared with resident females, with an important influence from the reproductive status of the host. A partial negative relationship between ectoparasite loads and latitudinal migration therefore was demonstrated.

Understanding species distributions and the variation of assemblage structure in time and space are fundamental goals of biogeography and ecology. Here, we use an ecological niche modeling and macroecological approach in order to assess whether constraints patterns in carnivoran richness and composition structures in replicated assemblages through time and space should reflect environmental filtering through ecological niche constraints from the Last Inter-glacial (LIG), Last Glacial Maximum (LGM) to the present (C) time. Our results suggest a diverse distribution of carnivoran co-occurrence patterns at the continental scale as a result of spatial climatic variation as an important driver constrained by the ecological niches of the species. This influence was an important factor restructuring assemblages (more directly on richness than composition patterns) not only at the continental level, but also from regional and local scales and this influence was geographically different throughout the space in the continent. These climatic restrictions and disruption of the niche during the environmental changes at the LIG-LGM-C transition show a considerable shift in assemblage richness and composition across the Americas, which suggests an environmental filtering mainly during the LGM, explaining between 30 and 75% of these variations through space and time, with more accentuated changes in North than South America. LGM was likely to be critical in species functional adaptation and distribution and therefore on assemblage structuring and rearranging from continental to local scales through time in the continent. Still, extinction processes are the result of many interacting factors, where climate is just one part of the picture.

Cave bats have an intimate association with their roosts. Size, structural heterogeneity, and microclimatic conditions are traits of caves known to affect the structure of these assemblages. The effects of the natural and anthropogenic landscape factors around caves on the structure of these assemblages are poorly known, especially in areas with large cave clusters. We assessed the effects of cave size and surrounding landscape attributes on the richness and species composition of cave-roosting bats in 13 caves distributed in two landscapes with large cave clusters in Caatinga dry forests, Brazil. In a 1-km buffer around caves, we obtained 13 internal cave and external landscape variables. Candidate univariate models using generalized linear models were constructed and the Akaike information criterion was used for model selection. The cave size model explained richness and variance in the species composition; larger caves tended to have greater richness and assemblage composition varied depending on the cave size, hence affecting the occurrence of certain species, some of conservation concern (Natalus macrourus, Furipterus horrens). The cave connectivity model affected only the richness; caves located in denser cave clusters had higher richness likely attributed to movement of bats among caves by a more diverse array of species. Both environmental and anthropic variables affected species composition, but differently depending of the landscape context of cave location (protected versus nonprotected area). The extent these landscape variables affected the species composition was due to species-specific responses, and observed in the mean colony sizes of the species shared between the cave systems. All the landscape variables that we tested affected the structuring process of cave-roosting bats assemblages, and evidences that variables found in disturbed karstic landscapes also affect the structure of the assemblage (e.g., large colonies of vampire bats). However, the ubiquitous effect of cave size on both richness and species composition reinforces the critical importance of the roost in the life of these flying mammals. Os morcegos que se abrigam em cavernas têm uma associação muito íntima com seus abrigos. Sabe-se que as características de caverna, como o tamanho, heterogeneidade estrutural e condições microclimáticas estáveis, afetam a estrutura das assembleias dos morcegos cavernícolas. No entanto, os efeitos dos fatores externos naturais e antrópicos da paisagem em torno de cavernas na estrutura das assembleias destes morcegos são pouco conhecidos, especialmente em paisagens cársticas com grandes aglomerados de cavernas. Assim, avaliamos os efeitos do tamanho da caverna e dos atributos da paisagem circundante na riqueza e composição de espécies de morcegos em 13 cavernas distribuídas em duas paisagens de Caatinga com grandes aglomerados de cavernas no Rio Grande do Norte. Em um buffer de 1 km ao redor de cada caverna, obtivemos 13 variáveis de paisagem interna (tamanho da caverna) e externa (número de cavernas circundantes, variáveis antropogênicas e ambientais); Modelos candidatos univariados usando GLM foram construídos e o Critério de Informação de Akaike foi usado para a seleção dos modelos. O modelo de tamanho das cavernas explicou a riqueza e a variação na composição das espécies; cavernas maiores tendem a ter maior riqueza e composição da assembleia variando de acordo com o tamanho da caverna, afetando, portanto, a ocorrência de certas espécies, algumas vulneráveis (Natalus macrourus, Furipterus horrens). O modelo de conectividade da caverna afetou apenas a riqueza; cavernas localizadas em aglomerados maiores tinham maior riqueza. As variáveis ambientais e antrópicas afetaram diferentemente a composição das espécies dependendo do contexto da paisagem da localização da caverna (área protegida versus não protegida). As variáveis da paisagem afetaram a composição das espécies ocorreu de uma forma específica em algumas espécies e foi observada no tamanho médio das colônias das espécies compartilhadas entre os sistemas de cavernas. Todas as variáveis da paisagem que testamos afetaram o processo de estruturação de assembleias de morcegos cavernícolas, incluindo aquelas que são características de uma paisagem cárstica perturbada. Todas as variáveis de paisagem que testamos afetaram o processo de estruturação de assembleias de morcegos que pousam em cavernas e evidenciam que variáveis encontradas em paisagens cársticas perturbadas também afetam a estrutura da assembleia (por exemplo, grandes colônias de morcegos vampiros). No entanto, o efeito ubíquo do tamanho da caverna sobre a riqueza e a composição das espécies reforça a importância crítica do abrigo na vida desses mamíferos voadores.

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Migratory animals live in a world of constant change. Animals undergo many physiological changes preparing themselves for the migration. Although this field has been studied extensively over the last decades, we know relatively little about the seasonal changes that occur in the microbial communities that these animals carry in their guts. Here, we assessed the V4 region of the 16S rRNA high-throughput sequencing data as a proxy to estimate microbiome diversity of tequila bats from fecal pellets and evaluate how the natural process of migration shapes the microbiome composition and diversity. We collected samples from individual bats at two localities in the dry forest biome (Chamela and Coquimatlán) and one site at the endpoint of the migration in the Sonoran Desert (Pinacate). We found that the gut microbiome of the tequila bats is dominated largely by Firmicutes and Proteobacteria. Our data also provide insights on how microbiome diversity shifts at the same site in consecutive years. Our study has demonstrated that both locality and year-to-year variation contribute to shaping the composition, overall diversity, and “uniqueness” of the gut microbiome of migratory nectar-feeding female bats, with localities from the dry forest biome looking more like each other compared to those from the desert biome. In terms of beta diversity, our data show a stratified effect in which the samples’ locality was the strongest factor influencing the gut microbiome but with significant variation between consecutive years at the same locality. IMPORTANCE Migratory animals live in a world of constant change. The whole-body ecosystem needs a strong adapting capacity to thrive despite the changes. Our study used next-generation sequencing to determine how gut microbial change along the migratory path of the nectar-feeding tequila bats. The study of the gut microbiome is a great tool that can provide important insights that are relevant not just for management and conservation but also an initial investigation of the extent of the adaptation and preparedness of the individual animals, with respect not just to their current environment but also to all the environments involved in their yearly cycle.

Myotis planiceps is an insectivorous species with a distinctive flat-headed morphology among Myotis species. Its distribution is restricted to the northeastern Mexico highlands, and uses trees of Yucca carnerosana to roost. The particular ecological and morphological characteristics of this species make it a likely resource-use specialist. We evaluated the morphological specialization of M. planiceps as compared with thirteen American congeners belonging to different dietary categories, using a geometric morphometric protocol and multivariate statistical analyses. We estimated morphological differences across dietary categories, including M. planiceps as a separate group, and evaluated the effect of cranial size and diet on variations in cranial morphology. We found a significant differentiation of this species in all the cranial shape characters, with soft insectivores as the dietary group closest to M. planiceps. Additionally, diet explained similar percentages of shape variance in cranial and mandibular characters, and the highest interaction between diet and cranial size was recorded in the braincase. In general, the smallest sizes and thinner skulls were observed in soft insectivores. Our findings do not support a significant relationship between skull shape characters, described by the first principal component, and hardness of food items, but we found a significant association with the mandible shape. No phylogenetic structure was observed in the residual variance of these models. We found trends of change in cranial morphology associated with specialized habitats, the mandibular characters being more contrasting in the fishing bat M. vivesi, and the braincase morphology being more contrasting in M. planiceps, a species that lives in restricted habitats and probably feeds on soft insects.

Bats are assumed not to use vision for communication, despite recent evidence of their capacity for color vision. The possibility that bats use color traits as signals has thus been overlooked. Some tent-roosting bats have a potential for visual signaling because they exhibit bright yellow skin, a trait that in birds often acts as a sexual signal. We searched for evidence of sexual dichromatism in the yellow bare skin of Honduran white bats Ectophylla alba, the first reported mammal with a capacity to deposit significant amounts of carotenoid pigments in the skin. We found that skin yellow chroma, a measure that reflects carotenoid content, increases in the ears and nose-leaf during development probably due to an increase in dietary carotenoid accumulation. Once in the adulthood, the yellow color of the nose-leaf becomes brighter in males, representing the first evidence of sexual dichromatism in a bat. The nose-leaf brightness tends to covary positively with the body condition of males. We also found that the skin shows a reflectance peak at 530 nm that virtually coincides with the main reflectance peak (540 nm) of the back side of Heliconia leaves used as roosts. This suggests that these leaves were selected because of camouflage benefits, and the rich lighting conditions of these roosting places then favored the use of skin coloration as a sexual signal. These findings open a new perspective in the physiological and behavioral ecology of bats in which vision has a more relevant role than previously thought.

Migration of ungulates (hooved mammals) is a fundamental ecological process that promotes abundant herds, whose effects cascade up and down terrestrial food webs. Migratory ungulates provide the prey base that maintains large carnivore and scavenger populations and underpins terrestrial biodiversity (fig. S1). When ungulates move in large aggregations, their hooves, feces, and urine create conditions that facilitate distinct biotic communities. The migrations of ungulates have sustained humans for thousands of years, forming tight cultural links among Indigenous people and local communities. Yet ungulate migrations are disappearing at an alarming rate (1). Efforts by wildlife managers and conservationists are thwarted by a singular challenge: Most ungulate migrations have never been mapped in sufficient detail to guide effective conservation. Without a strategic and collaborative effort, many of the world's great migrations will continue to be truncated, severed, or lost in the coming decades. Fortunately, a combination of animal tracking datasets, historical records, and local and Indigenous knowledge can form the basis for a global atlas of migrations, designed to support conservation action and policy at local, national, and international levels.

Exceptionally long-lived species, including many bats, rarely show overt signs of aging, making it difficult to determine why species differ in lifespan. Here, we use DNA methylation (DNAm) profiles from 712 known-age bats, representing 26 species, to identify epigenetic changes associated with age and longevity. We demonstrate that DNAm accurately predicts chronological age. Across species, longevity is negatively associated with the rate of DNAm change at age-associated sites. Furthermore, analysis of several bat genomes reveals that hypermethylated age- and longevity-associated sites are disproportionately located in promoter regions of key transcription factors (TF) and enriched for histone and chromatin features associated with transcriptional regulation. Predicted TF binding site motifs and enrichment analyses indicate that age-related methylation change is influenced by developmental processes, while longevity-related DNAm change is associated with innate immunity or tumorigenesis genes, suggesting that bat longevity results from augmented immune response and cancer suppression., DNA methylation profiles from 26 bat species accurately predicts chronological age, while longevity-related methylation patterns across the genome suggest that bat longevity results from augmented immune response and cancer suppression.

The jaguar (Panthera onca) is one of the most threatened carnivores in the Americas. Despite a long history of research on this charismatic species, to date there have been few systematic efforts to assess its population size and status in most countries across its distribution range. We present here the results of the two National Jaguar Surveys for Mexico, the first national censuses in any country within the species distribution. We estimated jaguar densities from field data collected at 13 localities in 2008–2010 (2010 hereafter) and 11 localities in 2016–2018 (2018 hereafter). We used the 2010 census results as the basis to develop a National Jaguar Conservation Strategy that identified critical issues for jaguar conservation in Mexico. We worked with the Mexican government to implement the conservation strategy and then evaluated its effectivity. To compare the 2010 and 2018 results, we estimated the amount of jaguar-suitable habitat in the entire country based on an ecological niche model for both periods. Suitable jaguar habitat covered ~267,063 km2(13.9% of the country’s territory) in 2010 and ~ 288,890 km2(~14.8% of the country’s territory) in 2018. Using the most conservative density values for each priority region, we estimated jaguar densities for both the high and low suitable habitats. The total jaguar population was estimated in ~4,000 individuals for 2010 census and ~4,800 for the 2018 census. The Yucatan Peninsula was the region with the largest population, around 2000 jaguars, in both censuses. Our promising results indicate that the actions we proposed in the National Jaguar Conservation Strategy, some of which have been implemented working together with the Federal Government, other NGO’s, and land owners, are improving jaguar conservation in Mexico. The continuation of surveys and monitoring programs of the jaguar populations in Mexico will provide accurate information to design and implement effective, science-based conservation measures to try to ensure that robust jaguar populations remain a permanent fixture of Mexico’s natural heritage.

Wing mites of the genus Periglischrus are ectoparasites exclusively associated with phyllostomid bats. These mites show high host specificity and have been studied to understand the evolutionary history of their bat hosts mainly by using a morphological variation. Through a phylogeographic approach, we analyzed the genetic diversity and population genetic structure of the ectoparasite Periglischrus paracaligus Herrin and Tipton which parasitizes Leptonycteris yerbabuenae Martínez and Villa (lesser long-nosed bat) in Mexico. By the implementation of a multilocus approach, we found that P. paracaligus populations were diverse for haplotype diversity, and had values ranging from 0.5 to 1. No genetic structuring in the P. paracaligus parasites was observed along with the distribution of the host, L. yerbabuenae, in Mexico, nor when populations or regions were compared, but our results revealed a process of historical demographic expansion in all the analyzed markers. We discuss possible scenarios that could explain the lack of population structure in the light of the data analyzed for the parasites and the biology of L. yerbabuenae, such as the interplay between parasite and host traits being responsible for the genetic make-up of parasite populations. We also inferred its phylogenetic position among wing mites parasitizing the two other species of Leptonycteris bats. Long-nosed bats’ monophyly helps to explain the observed presence of distinctive clades in the wing mite’s phylogeny in specific association with each long-nosed bat host species.

Bats hold considerable potential for understanding exceptional longevity because some species can live eight times longer than other mammals of similar size [1]. Estimating their age or longevity is difficult because they show few signs of aging. DNA methylation (DNAm) provides a potential solution given its utility for estimating age [2-4] and lifespan [5-7] in humans. Here, we profile DNAm from wing biopsies of nearly 700 individuals representing 26 bat species and demonstrate that DNAm can predict chronological age accurately. Furthermore, the rate DNAm changes at age-informative sites is negatively related to longevity. To identify longevity-informative sites, we compared DNAm rates between three long-lived and two short-lived species. Hypermethylated age and longevity sites are enriched for histone and chromatin features associated with transcriptional regulation and preferentially located in the promoter regions of helix-turn-helix transcription factors (TFs). Predicted TF binding site motifs and enrichment analyses indicate that age-related methylation change is influenced by developmental processes, while longevity-related DNAm change is associated with innate immunity or tumorigenesis genes, suggesting that bat longevity results, in part, from augmented immune response and cancer suppression.

Vaccines that autonomously transfer among individuals have been proposed as a strategy to control infectious diseases within inaccessible wildlife populations. However, rates of vaccine spread and epidemiological efficacy in real-world systems remain elusive. Here, we investigate whether topical vaccines that transfer among individuals through social contacts can control vampire bat rabies-a medically and economically important zoonosis in Latin America. Field experiments in three Peruvian bat colonies, which used fluorescent biomarkers as a proxy for the bat-to-bat transfer and ingestion of an oral vaccine, revealed that vaccine transfer would increase population-level immunity up to 2.6 times beyond the same effort using conventional, non-spreadable vaccines. Mathematical models showed that observed levels of vaccine transfer would reduce the probability, size and duration of rabies outbreaks, even at low but realistically achievable levels of vaccine application. Models further predicted that existing vaccines provide substantial advantages over culling bats-the policy currently implemented in North, Central and South America. Linking field studies with biomarkers to mathematical models can inform how spreadable vaccines may combat pathogens of health and conservation concern before costly investments in vaccine design and testing.

Letter to the Editor COVID-19 has spread around the globe, with massive impacts on global human health, national economies and conservation activities. In the timely editorial about conservation in the maelstrom of COVID-19, Evans et al. (2020) urged the conservation community to collaborate with other relevant sectors of society in the search for solutions to the challenges posed by the current pandemic, as well as future zoonotic outbreaks. Considering the association of COVID 19 with bats (Zhou et al., 2020), bat conservationists will undoubtedly be key actors in this dialogue, and thus an action plan on how best to adjust bat conservation to this new reality, alongside a transdisciplinary research agenda, are clear priorities info:eu-repo/semantics/publishedVersion

For species widely distributed on the American continent, we can expect to find divergent lineages because historical events, such as the Andean uplift, the emergence of the Panama isthmus, and the Milankovitch climate cycles, affected genetic connections among populations, as well as population sizes. There are only one mammalian species on the American continent, which shows a transcontinental distribution (from South to North America) and had a South American origin, the nine-banded armadillo (Dasypus novemcinctus). By sampling 242 D. novemcinctus from 16 countries, we explored the number of mitochondrial lineages across its complete range and assessed the climatic distribution and demographic history. We found four well-supported and highly divergent monophyletic lineages, which show a parapatric distribution. The geographic distribution of three of those lineages is wide, and the climatic conditions that they occupy are very different. In the middle of the Pleistocene, strong demographic expansions occurred in populations from three lineages, while in the Last Glacial Maximum (LGM), population sizes of the four lineages apparently were stable, despite the dramatic changes detected in available areas with a suitable habitat. The geographic distribution of the mitochondrial lineages does not correspond with the six subspecies defined by morphological characteristics. Our results provide tools for planning future studies utilizing ecological, morphological, and genomic analyses to elucidate the number of taxonomic units, which should be recognized. A clear delineation of the distribution and status of these units will be invaluable for the conservation management of the nine-banded armadillo.

Although the Near Threatened jaguarPanthera oncaranges from the south-west USA to central Argentina, populations outside Amazonia are generally small and isolated. One such area, the Sierra Madre de Chiapas in the state of Chiapas, Mexico, is potentially an important area for jaguar conservation but information on the species in this region is limited and its conservation status is unknown. In this study we documented the occurrence and abundance of jaguars in the Sierra Madre de Chiapas complex. We compiled all available records of the species within the region and conducted a camera-trap survey during August 2015–December 2016. Interviews were conducted to determine the perception of the jaguar by cattle owners and to obtain information on any livestock predation. We found that jaguars still occur throughout the Sierra Madre de Chiapas landscape, including the plains on the Pacific Coast of Chiapas, but its abundance in the region is low. On the basis of our findings we have incorporated the Sierra Madre de Chiapas in Mexico's National Jaguar Conservation Strategy, and recommend that international organizations include this area in their priorities for jaguar conservation. To improve coexistence between jaguars and the communities of the Sierra Madre de Chiapas, strategies need to be developed, in collaboration with the local communities, to improve livestock practices for reduction of predation by jaguars, to strengthen government conservation policies and to implement educational and communication programmes about the importance of this species in the region.

Gene flow and historical demography influence the level and distribution of population genetic variation. The nectar-feeding bat Leptonycteris yerbabuenae is a colonial and migratory species in tropical and subtropical regions of North America. We examined the distribution of genetic diversity among colonies of this species and assess whether a population in Baja California Peninsula shows signature of historical demographic change. We expected low genetic differentiation, because individuals are highly mobile and share mating sites. We also predicted a demographic signature consistent with past climatic fluctuations. During the spring maternity season, we sampled 120 individuals of six colonies along a 450 km transect in the Baja California Peninsula, Mexico. Individuals were genotyped with eight nuclear microsatellite loci and 1739 bp of two mitochondrial markers. We record weak but significant levels of nuclear structure and no mitochondrial differentiation among these colonies suggesting a high level of gene flow mediated by females. Genetic diversity estimation per colony and in the region was moderate, and consistent with previous studies. The mitochondrial data indicate that the population in the Baja California Peninsula experienced a demographic expansion during or after the late Pleistocene, probably related to the expansion of food resources. This is the first detailed genetic population study of L. yerbabuenae on the spatially disjunct part of its geographical range and it is the first record of a demographic expansion in a migratory nectar-feeding bat species from North America. Our results contribute to understanding the past demography and the natural history of this species in the Baja California Peninsula.

Parasites are a selective force that shape communities and ecosystems. Hosts represent a food source, habitat, and a way to disperse. In recent years, investigations dealing with bats and their role as hosts to numerous parasitic organisms, including metazoan ectoparasites and endoparasites have increased, and soft ticks (Parasitiformes: Ixodida: Argasidae) are among the best known. In Mexico, 16 species of soft ticks associated with bats have been reported up to now, but there are no specific records of soft ticks parasitizing Leptonycteris yerbabuenae in the country. Herein, we record for the first time the presence of Ornithodoros dyeri parasitizing L. yerbabuenae and report an extension of its geographic distribution. The same tick species was also recorded from the California leaf-nosed bat (Macrotus californicus). Data on prevalence, mean intensity, mean abundance, tick identification, and possible scenarios of life cycle associations for O. dyeri and one of its hosts, L. yerbabuenae, are discussed.

Migratory species that cross geopolitical boundaries pose challenges for conservation planning because threats may vary across a species’ range and multi-country collaboration is required to implement conservation action plans. The lesser long-nosed bat (Leptonycteris yerbabuenae) is a migratory pollinator bat that was removed from the Endangered Species List in the United States in 2018 and from threatened status in Mexico in 2013. The seasonal ecology and conservation status of the species is well understood in the core part of its range on mainland Mexico and in the southwestern United States, but relatively little is known about the species on the Baja California peninsula in northwestern Mexico, a part of its range range separated by the Gulf of California. We studied the seasonal ecology of lesser long-nosed bats on the Baja peninsula at 8 focal roosts along a 450-km north-to-south transect to test hypotheses about migratory or residential status of the species on the Baja peninsula. We provide evidence of an extensive population of lesser long-nosed bats on the Baja peninsula that is primarily seasonally migratory and includes 2 mating roosts with males on the southern part of the peninsula. Seasonal ecology of lesser long-nosed bats was closely associated with the flowering and fruiting season of the cardón (Pachycereus pringlei), the dominant columnar cactus on the peninsula. However, we discovered that some female lesser long-nosed bats arrive and give birth at southern roosts in mid-February, about 2 months earlier than other migratory populations in more northern Sonoran Desert habitats. We documented the loss of nearly a third of the known maternity roosts during the study, demonstrating that action to protect key roosts remains a high priority. Migratory pollinators are particularly vulnerable to climate and land-use changes and we recommend continued monitoring and research to guide effective range-wide conservation of the species. Las especies migratorias o con rangos de distribución amplios que incluyen fronteras geopolíticas, representan desafíos particulares para la planificación de estrategias de conservación, ya que las amenazas así como las tendencias poblacionales pueden variar a lo largo de su rango geográfico y se requiere la colaboración de múltiples países para implementar planes de acción que permitan su conservación. El murciélago magueyero menor (Leptonycteris yerbabuenae) es un murciélago polinizador migratorio que recientemente fue sacado de la lista de especies en peligro en los Estados Unidos en 2018 y en México en 2013. La ecología estacional y el estatus de conservación de esta especie, ha sido bien estudiado en el centro de su rango de distribución en México continental, pero se sabe muy poco acerca de la especie en la Península de Baja California en el noreste de México, región que está separada del resto del rango por el golfo de California. Nosotros estudiamos la ecología estacional del murciélago magueyero menor, en ocho cuevas a lo largo de un transecto de 450 km norte-sur, en la Península de Baja California y pusimos a prueba la hipótesis del status migratorio o residente de sus poblaciones en esta región. Proporcionamos la primera evidencia de una extensa población de esta especie en la península, a cual es principalmente migratoria estacional e incluye dos cuevas de reproducción ubicadas al sur de esta región. La ecología estacional del murciélago magueyero menor estuvo fuertemente asociada con la estación de floración y fructificación del cardón (Pachycereus pringlei), el cactus columnar dominante en la península. Nosotros también descubrimos que algunas hembras llegan y dan a luz en las cuevas más sureñas, a mediados de febrero, cerca de dos meses antes que otras poblaciones migratorias, en el desierto de Sonora del norte. Durante el tiempo de este estudio, documentamos la destrucción de una de las cuevas de maternidad, lo que demuestra la necesidad de acciones de conservación para proteger estos refugios. Los polinizadores migratorios son particularmente vulnerables a cambios en el uso del suelo y al cambio climático y recomendamos continuar con el monitoreo y la investigación, con el fin de guiar su conservación a lo largo de todo el rango de distribución de la especie.

The aim of this research was to detect rabies virus in peripheral tissues in captive vampires. Vampire bats were inoculated with 106 MICLD50 of homologous rabies virus. Bats displayed clinical signs of rabies beginning on d 8 until the 19th d post-inoculation (pi). Rabies virus antigens were found in the brain of all rabid bats. Viral RNA was detected in brain, salivary gland and tongue tissue by RT-PCR and nested PCR (nPCR). Viral genome was also detected in organs unrelated to the central nervous system. Rabies virus was not detected in saliva nor documented from any tissues without occurrence of viral antigens in the brain. Host humoral response was most pronounced via the induction of viral neutralizing antibodies (VNA) from d 8 to 20 pi, having a peak at d 14 with 0.9 IU. Antibody levels were variable, but tended to remain high after inoculation, showing significant differences to the negative control group (P=0.001). This research is one of the few recent studies focused upon Desmodus rotundus and contributes to the basic knowledge of rabies virus pathogenesis, which is required for an understanding of perpetuation in a major viral reservoir in Latin America.

Bats show the greatest variety of mating strategies in mammals. Social structure can be influenced by roost characteristics, for example, if the roost is defendable and its availability limited, it becomes an important resource that partially determines the mating system type. In the species that use tents as roosting sites, it has been suggested that males can defend the tent in order to attract and have access to females. Ectophylla alba is an obligate and exclusive tent user, and it has to build tents periodically. Its mating system has been classified as polygyny by its resource defense, and it has a temporary group structure of one male and several females. This study seeks to determine the composition and stability of the groups of this species and to learn whether males defend the tent or the females in it in order to gain copulations. This study was conducted in 2006 in Tirimbina, Biological Reserve in Sarapiqui, Costa Rica, where groups of bats were captured (N = 38). The individuals were marked (N = 98), and their reproductive status was determined. The behavior of the individuals was recorded with video cameras and infrared light (300 h total). Throughout the year, some individuals were more closely associated to other individuals, determining that groups are stable independent of the reproductive season. The proportion of males in the groups does not vary according to reproductive season, and in most groups, there is more than one adult male. The males spend different amounts of time in the tents and do not show antagonistic behavior with other members of the group. Based on the social structure, the classification of the mating system should change to “a stable group of several males and females,” which may be confirmed in the near future by the results of an ongoing paternity study.

Nightly movements of bats have been described for only a handful of species around the world. The lesser long-nosed bat (Leptonycteris yerbabuenae) is a migratory pollinator recently delisted from threatened status in Mexico and proposed in early 2017 to be delisted from endangered status in the United States. Documenting the nightly movements of these bats and how they use the desert ecosystem when they spend the summer in Sonora, Mexico, is critical for protection of their habitat and to understand food availability and landscape use. We used inert fluorescent powder to mark thousands of bats emerging from a cave used as a day roost, then examined bats captured at known foraging sites for this marker. We also marked individuals captured at foraging sites with different colors of powder that enabled us to search for dyed feces in the cave. Our results demonstrate that these bats made round trips of ca. 100 km flying from their roost cave to their nightly foraging grounds, which exceeds all distances known from other phyllostomid or nectar-feeding bats in the world.