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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.

The Central American brocket deer (Mazama temama) is widespread across the Mesoamerican forests, yet it remains largely unknown. Three subspecies are recognized currently within M. temama using pelage coloration as the primary diagnostic character. However, it remains unclear if there is any pattern of morphological variation throughout its distribution. We compared two models of morphological subdivision, namely the traditional subspecies and another based on biogeographic provinces via 2D geometric morphometrics and ecological niche modeling. The second model presented a better fit to the observed variation in cranial shape and size. We found divergence in skull size between individuals from Mexico and Guatemala (northern group) relative to specimens from Honduras, Nicaragua, Costa Rica, and Panama (southern group), the latter being 8% larger than the northern group. Centroid size showed a significant correlation with geographic distance suggesting an isolation-by-distance pattern. Low geographical overlap between the two clusters suggests niche conservatism. Late Pleistocene dispersal from South to Central America and differences in available resources with subsequent isolation due to climatic barriers therefore may have promoted differentiation in size albeit without extensive changes in shape. In this context, the Motagua-Polochic-Jolotán fault system probably plays a key role in promoting morphological differentiation by climatic isolation. Finally, we suggest that M. t. temama (Kerr, 1792) and M. t. reperticiaGoldman, 1913 should remain as valid names for the two morphological and ecologically differentiated groups detected here.

The gray wolf, Canis lupus, once inhabited much of the northern hemisphere worldwide; however, persecution drove its populations almost to extinction. In North America, diverse conservation programs have been implemented in the last decades to recover its populations in the wild, many of them guided by the historical distribution of the gray wolf subspecies. Over time, several authors have proposed different subspecies classifications. Nevertheless, most of them are mutually inconsistent regarding the number and distribution of subspecies, creating controversy when implementing conservation programs. This study used niche-based distribution models and cluster analysis to explore the bioclimatic profiles of C. lupus across North America and compare them with different subspecies classifications to identify environmental correlatives that support the proposed designations. Our cluster analysis results indicate that the optimal number of climatic groups was five, designated as Northern, Eastern, Western, Coastal, and Southern groups, with transitional overlap boundaries located at their peripheries, indicating climatic gradients between them and supporting the idea of intergrading zones. The geographic ranges of these groups mismatched to a different extent with all subspecies delimitations. In general, the boundaries of putative subspecies did not match the climatic patterns of North America. Our results may contribute to the recovery programs underway for this carnivore by identifying suitable areas for the release of individuals from specific lineages. New approaches to characterizing the intraspecific variation of the gray wolf should include all evidence available, including genetic, morphological, and ecological information.

Las emisiones antropogénicas de gases de efecto invernadero están causando un calentamiento del océano que tiene graves consecuencias para la biodiversidad marina. Entre las especies más vulnerables al cambio climático se encuentra la ballena jorobada, cuyas poblaciones se distribuyen en todos los océanos del mundo y realiza migraciones desde las zonas polares y templadas, donde se alimenta, hasta las áreas tropicales, donde se reproduce. El cambio climático ha alterado la disponibilidad de las presas de la ballena, provocando cambios en la duración de sus migraciones, su distribución, su estado de salud y su reproducción. Como resultado, algunas poblaciones de esta especie se encuentran En Peligro, aunque aún se conoce poco sobre los efectos precisos del cambio climático en su ecología y su población. Para abordar esta problemática, es necesario llevar a cabo estudios interdisciplinarios que permitan obtener información sobre la ballena jorobada desde diferentes perspectivas, a fin de construir estrategias de mitigación que estén alineadas con el enfoque de Una Salud y los Objetivos de Desarrollo Sostenible (ods).

The most popular sources of information on species distributions are the expert-derived maps and georeferenced occurrences, mainly those compiled by the Global Biodiversity Information Facility (GBIF). These sources have been constantly used with biogeographical and conservation goals. However, their degree of accuracy in representing geographical biodiversity patterns remains poorly understood. Here, we compared both sources of information on species distributions to estimate global patterns of richness and species composition of threatened vertebrates on marine islands.

The field of distributional ecology has seen considerable recent attention, particularly surrounding the theory, protocols, and tools for Ecological Niche Modeling (ENM) or Species Distribution Modeling (SDM). Such analyses have grown steadily over the past two decades—including a maturation of relevant theory and key concepts—but methodological consensus has yet to be reached. In response, and following an online course taught in Spanish in 2018, we designed a comprehensive English-language course covering much of the underlying theory and methods currently applied in this broad field. Here, we summarize that course, ENM2020, and provide links by which resources produced for it can be accessed into the future. ENM2020 lasted 43 weeks, with presentations from 52 instructors, who engaged with >2500 participants globally through >14,000 hours of viewing and >90,000 views of instructional video and question-and-answer sessions. Each major topic was introduced by an “Overview” talk, followed by more detailed lectures on subtopics. The hierarchical and modular format of the course permits updates, corrections, or alternative viewpoints, and generally facilitates revision and reuse, including the use of only the Overview lectures for introductory courses. All course materials are free and openly accessible (CC-BY license) to ensure these resources remain available to all interested in distributional ecology.

Non-native (invasive) species offer a unique opportunity to study the geographical distribution and range limits of species, wherein the evolutionary change driven by interspecific interactions between native and non-native closely related species is a key component. The red-eared slider turtle, Trachemys scripta elegans (TSE), has been introduced and successfully established worldwide. It can coexist with its native congeners T. cataspila, T. venusta and T. taylori in Mexico. We performed comprehensive fieldwork, executed a battery of genetic analyses and applied a novel species distribution modelling approach to evaluate their historical lineage relationships and contemporary population genetic patterns. Our findings support the historical common ancestry between native TSE and non-native (TSE