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Leopardus wiedii and Leopardus pardalis are endangered small felids. Its main altitudinal range expands from sea level to 1,500 m. Camera traps were placed in the Matawi Indigenous Park on the Nevado de Toluca Volcano. Photographic records were obtained of L. wiedii at 3,207 masl and of L. pardalis at 3,307 masl. This is the highest altitudinal record for margay in its distribution, and for ocelot is the highest in the northern hemisphere. [ABSTRACT FROM AUTHOR]

Copyright of Caldasia is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the most obvious impacts of roads is roadkill, a problem that is recently being addressed in Mexico. However, there are economic and human resource limitations to monitor the entire road network, assess its impacts, and propose mitigation measures. The black bear (Ursus americanus) is a top predator and the largest terrestrial mammal distributed in Mexico, currently the only of the Ursidae family. In recent years, its presence near human settlements and incidents on roads has increased. We generated a single MaxEnt model to identify characteristics of sites with high black bear roadkill risk and to identify these areas within protected natural areas. We obtained 83 bear roadkill records between 2008 and 2022, and we used a set of 16 variables that included landscape, road variables, and human variables. The model had an area under curve value of 0.96 indicating good performance and the Jacknife analysis identified influence on the roadkill risk of the distance to water bodies, protected areas, scrubland, drainages, and speed limit. We identified 3883.25 km of roads at high roadkill risk for black bears of which, 373.10 (9.6%) km were inside protected areas. We suggest placing speed bumps and effective signage on high-risk sections as a short-term, low-cost strategy. The results help to focus conservation efforts to specific sections of the road network, as roadkill is an increasing source of mortality that has not been evaluated for black bear in Mexico. This information is applicable for mitigating the impacts of existing roads and for planning new projects that have less impact on wild black bear populations and, at the same time, increase the safety of vehicle drivers. [ABSTRACT FROM AUTHOR]

Context. Road networks are related to two global problems: habitat loss and degradation, and the decline of biodiversity. Wildlife roadkill is one of the most obvious and immediate impacts of linear infrastructure that affects all vertebrate groups, and some species,such aslarge carnivores, are more susceptible to fragmentation by roads due to their wide-ranging movements and home ranges. Aims. Recently, black bear (Ursus americanus) sightings have increased in urban and suburban areas. The objectives of this study were: to identify and characterise road crossing sites used by black bears; to understand whether bears select specific landscape or road features for crossing; to compare crossing and roadkill sites; and to identify the most important variables in both groups to propose short-term mitigation strategies. Methods. For the analysis of crossing sites, black bear individuals were captured from 2014 to 2018 and released with a GPS collar. We also calculated the dynamic model of Brownian motion to identify the road crossing sites. We obtained collision records from field work and government agencies. We performed Firth’s penalisedlikelihood logistic regression models to identify the most important variables of highway or landscape in the probability of crossing or roadkill. Key results. We captured 15 black bear individuals (11 males and four females), seven of which crossed a road at least once. Most of the crossings occurred during the night, which explains the results of the regression model between crossing and roadkill sites because crossings are a function of the percentage of buses and urban use. We also found that the speed at roadkill sites is significantly higher than at crossing sites. Conclusions. This study contributed aspects necessary to understand the management of highways and reduce their impact on the black bear population in Mexico, such as the identification of priority mitigation sites. Systematic monitoring of roadkill in Mexico is required to propose specific mitigation sites that will benefit more vertebrate groups. Implications. The information generated in this research forms the basis of identification of optimal sites for strategies to mitigate the bear–road conflict and help the conservation of the species. [ABSTRACT FROM AUTHOR]

Copyright of Mammal Review is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Large carnivores have long fascinated human societies and have profound influences on ecosystems. However, their conservation represents one of the greatest challenges of our time, particularly where attacks on humans occur. Where human recreational and/or livelihood activities overlap with large carnivore ranges, conflicts can become particularly serious. Two different scenarios are responsible for such overlap: In some regions of the world, increasing human populations lead to extended encroachment into large carnivore ranges, which are subject to increasing contraction, fragmentation, and degradation. In other regions, human and large carnivore populations are expanding, thus exacerbating conflicts, especially in those areas where these species were extirpated and are now returning. We thus face the problem of learning how to live with species that can pose serious threats to humans. We collected a total of 5,440 large carnivore (Felidae, Canidae, and Ursidae; 12 species) attacks worldwide between 1950 and 2019. The number of reported attacks increased over time, especially in lower-income countries. Most attacks (68%) resulted in human injuries, whereas 32% were fatal. Although attack scenarios varied greatly within and among species, as well as in different areas of the world, factors triggering large carnivore attacks on humans largely depend on the socioeconomic context, with people being at risk mainly during recreational activities in high-income countries and during livelihood activities in low-income countries. The specific combination of local socioeconomic and ecological factors is thus a risky mix triggering large carnivore attacks on humans, whose circumstances and frequencies cannot only be ascribed to the animal species. This also implies that effective measures to reduce large carnivore attacks must also consider the diverse local ecological and social contexts. A worldwide study of large carnivore attacks on people analyzes and compares the main patterns and circumstances within and among species and across geographic regions, shedding light on this complex and critical type of human-wildlife conflict. [ABSTRACT FROM AUTHOR]

Dams must provide human development with economic viability, social equitability, and be environmentally sustainable However, environmental and social impacts are often negative and seldom considered in the design of these projects. We made a multitemporal analysis classifying 26 satellite images of several Mexican hydroelectric power stations between 1972 and 2016 to evaluate the effect of dams on the change in land use. Eleven socio-economic indicators were also compared before and after the construction of the dam to document effects on local communities. We use the Land Change Modeler to quantify the net changes in land use and land cover. We found a mean decrease in tropical forest (1,404.19 km2) and temperate forest (1,191.26 km2) and an increase in agriculture (2,241.26 km2) and urban use (92.9 km2). The results also show that although some indicators improved, the environmental deterioration around these projects shows that they are not sustainable. [ABSTRACT FROM AUTHOR]

In Mexico, information about ocelots is limited, which hinders the implementation of effective management and conservation measures. The purpose of this research was to provide basic information of population density, relative abundance and home range observed for the species in northwestern Mexico. Systematic sampling was implemented from January to December 2015 using photo-trapping as tool. Fifty-four camera-trap stations (37 double stations) were used, and the resulting grid covered an area of 182 km2. We applied six sampling periods of 59-62 days in each period. Density analysis was based on spatially explicit models and traditional capture-recapture models. The home range was estimated using the minimum convex polygon method. We obtained 135 photographic records of ocelots, of which 17 individuals were identified (five males, four females and eight individuals of undetermined sex). During six study periods, our sampling effort reached 19 710 trap-days. We estimate a capture rate for the study of 6.84 rec./1000 trap-days. The density of ocelots estimated with the Capture module in the MARK program ranged from 1.38 to 2.93 rec./100 km2. The results estimate using the SERC method showed a density of 0.93-3.06 individuals per 100 km2. The ocelots in the Northern Jaguar Reserve (NJR) had an average distribution area of 14.1 km2. The results of this research illustrate the importance of continuing studies of ocelots on the NJR to maintain a long-term viable population for northwestern Mexico. [ABSTRACT FROM AUTHOR]

Context: Land use change, habitat loss and fragmentation are the major threats to jaguar conservation in Latin America. Here, we integrate the information of jaguar's distribution to identify priority areas for its conservation. Objective: We evaluated the effect of topographic, anthropogenic and landscape variables on habitat suitability to evaluate potential core areas and biological corridors for jaguar conservation across Mexico. Methods: We compiled a database of jaguar occurrence records, geospatial data-set of all Natural Protected Areas and using the expert criterion of the Mexican jaguar specialists to define Jaguar Geographic Regions; i.e. well-defined large units with similar ecological characteristics across the geographic range of jaguars in Mexico. We then conducted analyses of ecological niche models to identify Jaguar Conservation Units; i.e. core units with jaguar populations of 15 or more individuals. We used Least Cost Path and Circuit Theory analyses to define the Biological Corridors; i.e. regions with enough habitat to allow for jaguar dispersal along their geographic range, but putting emphasis in connecting Jaguar Conservation Units. Results: We identified 5 Jaguar Geographic Regions (JGRs), 10 Jaguar Conservation Units (JCUs), and 13 Biological Corridors to maintain the connectivity of jaguar's populations across their whole geographic range in Mexico. Our results showed that JGRs cover 25% of the country but only 21% of those regions are currently protected in nature reserves. So, our study illustrates the importance of the creation of new protected areas or the implementation of other schemes of conservation to protect larger extensions of the jaguars' habitat in Mexico. It also indicates that despite the reduction of jaguar range in Mexico, there are still relatively large and well conserved areas capable of maintaining jaguar populations. Conclusions: Our results are a fundamental tool to guide the conservation and management of jaguars in Mexico. Our findings indicate that public jaguar conservation policy to protect the remaining jaguar habitat in Mexico should include the following actions: i) Strengthen established protected areas, ii) Create new protected areas, iii) Implement sustainable development programs to stimulate land owners to protect their lands, and iv) Develop mitigation measures for infrastructure. Although the window of opportunity is closing, our results indicate that there is still time to save jaguars and the plethora of species that share their habitat in Mexico. [ABSTRACT FROM AUTHOR]

Negative interactions between people and crocodilians have increased worldwide, but in Mexico there have been few systematic reports and no rigorous evaluation of this problem. We compiled information on negative interactions between people and the spectacled caiman Caiman crocodilus and American crocodile Crocodylus acutus from the Worldwide Crocodilian Attack Database for 1993–2018, and we investigated interactions in greater depth, through interviews with people in La Encrucijada Biosphere Reserve. We examined the relationship between the occurrence of negative interactions between people and C. acutus and the species' nesting season and abundance, and presence records. In Mexico, the frequency of negative interactions increases when anthropogenic activities occur close to nesting sites (< 30 km) and during the nesting season (February–September). In La Encrucijada, following negative interactions with crocodiles, the local inhabitants killed 30 crocodiles measuring > 2.5 m long in 2011–2012. The frequency of negative human–crocodilian interactions was not correlated with the abundance of crocodilians but was correlated with the number of presence records of crocodiles. Strategies to minimize these interactions include warnings at nesting sites, increased monitoring of anthropogenic activities during the nesting season, and management of nests to prevent them being destroyed by people. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia Ergo Sum is the property of Universidad Autonoma del Estado de Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the last century, the coyote (Canis latrans) has increased its distribution in Central America. Before the 1980s, it had not been recorded in Panama. New records show that coyotes have crossed the Panama Canal, indicating that continues to expand; therefore, there is a possibility that it will reach northern South America. Our objectives were to identify potential coyote colonization routes to South America, and the variables that favor its expansion. We hypothesized that habitat fragmentation benefits coyote expansion. We applied 7 algorithms to model the potential distribution of the coyote, using 196 presence records and 12 variables. The models with better performance were used to generate a consensus model. Using our consensus model and the areas with highest probability of presence, a potential colonization route was generated between Central America and northern South America. This route lies through southern Costa Rica, along the Pacific coast of Panama to the south, to the Andean mountains in northern Colombia. The variables that explained potential coyote distribution were human population density, altitude, and percentage of crops with positive influence, and tropical broadleaf forests with negative influence. These results indicate that human activities and deforestation are related to coyote distribution expansion. Actions can be implemented within the identified route to improve environmental management, in order to avoid the presence of the coyote in the ecosystems of northern South America. [ABSTRACT FROM AUTHOR]

Interactions between species and individuals can determine their survival in the wild. Most of the time these relationships are difficult to study in situ by direct observation. However, technology can help collect these data with minimal impact on animals' behaviour. Egg stage is certainly the most vulnerable life stage in crocodilians, but few studies have focused on animal species visiting crocodilian nests and associated egg predation. Herein, we use camera-traps in four Mexican states (Chiapas, Oaxaca, Jalisco, Tabasco) to determine vertebrate species and egg predators associated with wild nests of Caiman crocodilus chiapasius, Crocodylus acutus and Crocodylus moreletii. We recorded 72 species of vertebrates at nesting sites and obtained the first photographic evidence of crocodilian egg predation by Caracara cheriway, Cuniculus paca, Didelphis virginiana and Procyon lotor. We also identified commensalism, cooperation, and predation as types of interactions within observed nesting areas, which indicates the importance of crocodilian nesting areas for other wild vertebrates. Finally, we found that crocodilian egg predation depends on species richness present in the area of study, as well as crocodilian size. [ABSTRACT FROM AUTHOR]

Species coexistence at a given locality generally implies segregation along one of the three resource dimensions of the ecological niche: spatial, trophic or temporal. Temporal activity patterns of species are ecologically important as they expose how species exploit their environments. Using camera traps, we evaluated the temporal activity patterns and temporal overlap for a mammalian carnivore assemblage from Sierra Nanchititla Natural Park, central Mexico. We characterized and compared temporal activity patterns and temporal overlap between species pairs using circular statistics. Temporal overlap was analyzed using three temporal domains (full diel, diurnal, and nocturnal), and null models were used to contrast the empirical assemblage-wide temporal overlap in relation to randomly generated distributions. We found that pair-wise temporal overlap comparisons among species were quite heterogeneous and dependent on the temporal domain used for the analyses. Two major inferences can be derived from pair-wise analyses and the null model: (a) most of the carnivore assemblage show a nocturnal activity pattern in common and (b) most of the pair-wise comparisons indicate temporal segregation among species. The highest temporal overlap at the assemblage-wide level was found when only the nocturnal domain was evaluated and we found coincident temporal activities at the full domain level, independent of the temporal resolution used. Overall, our results suggest that carnivores with distinct trophic and habitat use like the margay (Leopardus wiedii) and gray fox (Urocyon cinereoargenteus) had temporal overlapping activity patterns to full diel and nocturnal domains, and species with similar trophic and habitat use always presented temporal segregation (gray fox and white-nosed coati, Nasua narica). Finally, species with predator-prey relationships (white-nosed coati and cougar, Puma concolor) showed segregation during the day but overlap at night. Our results indicate that species temporal activity patterns likely change in relation to different interspecific interactions such as predation and competition to allow species coexistence within this carnivore assemblage. [ABSTRACT FROM AUTHOR]

Land use changes are threatening the maintenance of biodiversity. Genetic diversity is one of the main indicators of biological diversity and is highly important as it shapes the capability of populations to respond to environmental changes. We studied eleven populations of Pseudoeurycea robertsi, a micro-endemic and critically endangered species from the Nevado de Toluca Volcano, a mountain that is part of the Trans-Mexican Volcanic Belt, Mexico. We sequenced the mitochondrial cytochrome b gene from 71 individuals and genotyped 9 microsatellites from 150 individuals. Our results based on the cytochrome b showed two divergent lineages, with moderate levels of genetic diversity and a recently historical demographic expansion. Microsatellite-based results indicated low levels of heterozygosity for all populations and few alleles per locus, as compared with other mole salamander species. We identified two genetically differentiated subpopulations with a significant level of genetic structure. These results provide fundamental data for the development of management plans and conservation efforts for this critically endangered species. [ABSTRACT FROM AUTHOR]

The golden eagle (Aquila chrysaetos) has been poorly studied in Mexico. Even though it is listed as threatened in this country, partly because of habitat fragmentation and direct persecution, little is known of its distribution. We assessed the potential distribution of this species in Mexico using ecological niche modelling (ecological niche factor analysis, artificial neural network, genetic algorithm for rule-set production, environmental distance, support vector machine, MaxEnt) and the weighted average ensemble method. The models were evaluated using the area under the curve of the receiver operating characteristics. We applied a threshold of 50% probability to obtain high-suitability areas and considered marginality and specialization calculated by ecological niche factor analysis and the most important variables to the model. We assessed and evaluated the percentage of high-suitability area occurring in all Mexican natural protected areas. The performance of the ensemble model was high (area under the curve = 0.93) and the most important variables contributing to the model were grasslands and tree cover percentage. The resulting high-suitability area is considerably fragmented, it comprises 16% of the country and just 8% of it is located in natural protected areas. We propose some urgent actions and conservation measures to face the main problems that are threatening the species in Mexico. [ABSTRACT FROM AUTHOR]

Information about human land uses, producing the least impact on wildlife and their habitats, is crucial to develop management strategies allowing coexistence between human beings and wildlife. We investigated the responses of the bobcat (Lynx rufus) and the coyote (Canis latrans) to different types of human activity by assessing the abundance, habitat use, and activity patterns of these species in response to extraction of firewood, grazing, and crop farming within their habitat. Photographic records of both carnivores were obtained from 18 camera-trap stations, distributed evenly within these three types of habitat disturbances. The highest relative abundance index for both carnivores was obtained at firewood extraction sites, followed by grazing sites, and croplands. The probability of carnivore sightings varied between species by type of disturbance and by season. The probability of bobcat sightings was highest within firewood extraction sites, with no effect of season, whereas that of the coyote was highest during winter, with no effect of type of human disturbance. An analysis of habitat use revealed that both carnivores avoided cropland sites. Activity patterns were similar, which suggests an absence of temporal segregation between these species; moreover, the activity patterns of both carnivores seems to be affected by intensity of human activities. Preference for woodland habitats by both carnivores denotes that firewood extraction is the disturbance that least affects bobcat and coyote populations; therefore, this kind of human activity could be the least impacting type of disturbance for the coexistence between humans and these carnivore species. [ABSTRACT FROM AUTHOR]

Copyright of Herpetozoa is the property of Pensoft Publishers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The isolated and fragmented populations are highly susceptible to stochastic events, increasing the extinction risk because of the decline in putative adaptive potential and individual fitness. The population has high heterozygosity values and a moderate allelic diversity, the heterozygosity values are higher than in most other Crotalus species and snake studies. Possibly these high levels of genetic diversity can be related to a large founder size, high effective population size, multiple paternity and overlapping generations. We did not find the genetic structuring but the effective number of alleles (Ne) was 138.1. We found evidence of bottlenecks and the majority of rattlesnakes were unrelated, despite the small sample size, endemic status, the isolated and fragmented habitat. The genetic information provided in this study can be useful as a first approach to try to make informed conservation efforts for this species and also, important to preserve the habitat of this species; the endangered Abies-Pinus forest of the Nevado the Toluca Volcano. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia Ergo Sum is the property of Universidad Autonoma del Estado de Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The study of predator–prey interactions is commonly analyzed using functional responses to gain an understanding of predation patterns and the impact they have on prey populations. Despite this, little is known about predator–prey systems with multiple prey species in sites near the equator. Here we studied the functional response of cougars (Puma concolor) in relation to their main prey, armadillo (Dasypus novemcinctus), coati (Nasua narica) and white‐tailed deer (Odocoileus virginianus). Between 2004 and 2010, cougar scats were collected along 5 transects to estimate the consumption of different prey species. A relative abundance index (RAI) was calculated for each prey species and cougar using 18 camera traps. We compared Holling type I, II and III functional response models to determine patterns in prey consumption based on the relative abundance and biomass of each prey species consumed. The 3 main prey species comprised 55% (armadillo), 17% (coati) and 8% (white‐tailed deer) of the diet. Type I and II functional responses described consumption of the 2 most common prey species armadillos and coati similarly well, while a type I response best characterized consumption of white‐tailed deer. A negative correlation between the proportions of armadillo versus coati and white‐tailed deer biomass in cougar scats suggests switching to consume alternative prey, confirming high foraging plasticity of this carnivore. This work represents one of the few studies to compare functional responses across multiple prey species, combined with evidence for prey‐switching at low densities of preferred prey. [ABSTRACT FROM AUTHOR]

Amphibians are globally threatened by habitat loss and fragmentation; species within the order Ambystoma are not the exception, as there are 18 species of mole salamanders in México, of which 16 are endemic and all species are under some national or international status of protection. The mole salamander, Ambystoma altamirani is a microendemic species, which is distributed in central México, within the trans-Mexican volcanic belt, and is one of the most threatened species due to habitat destruction and the introduction of exotic species. Nine microsatellite markers were used to determine the genetic structure, genetic variability, effective population size, presence of bottlenecks and inbreeding coefficient of one population of A. altamirani to generate information which might help to protect and conserve this threatened species. We found two genetic subpopulations with significant level of genetic structure (FST = 0.005) and high levels of genetic variability (Ho = 0.883; He = 0.621); we also found a small population size (Ne = 8.8), the presence of historical (M = 0.486) and recent bottlenecks under IAM and TPM models, with a low, but significant coefficient of inbreeding (FIS = -0.451). This information will help us to raise conservation strategies of this microendemic mole salamander species. [ABSTRACT FROM AUTHOR]

Top-down and bottom-up controls are hypothesized to regulate population structures in many ecosystems. However, few studies have had the opportunity to analyze both processes in the natural environment, especially on large carnivores like the cougar ( Puma concolor). Previously, studies show that cougar diet in the Sierra Nanchititla Natural Reserve (SNNR), central Mexico, is mainly armadillo, coati, and white-tailed deer. We assess whether top-down and/or bottom-up control regulate this endangered food web: (a) we predicted that seasonal per capita changes in abundance ( pca) of cougar will be positively affected by the abundance of their main prey; (b) primary productivity in SNNR will affect the pca of prey species, driving bottom-up control; and (c) armadillo, coati, and white-tailed deer pca will be affected by the abundance of cougar, generating top-down control. Using 15 camera traps for 6 years in the SNNR, we calculated a relative abundance index (RAI) and pca for cougar and each of the focal prey, and we used the normalized difference vegetation index (NDVI) as a proxy of primary productivity. We constructed multiple regression models and selected the best linear models based on ranking the AIC values. Our analysis suggests that P. concolor pca is best explained by bottom-up control and intraspecific feedback . White-tailed deer and armadillo pca were both significantly affected by cougar abundance, indicating top-down control for these prey species, but NDVI was not retained in any of the models selected for prey pca. Our results indicate that both bottom-up and top-down control are involved in regulating this endangered food web in the SNNR, Mexico. [ABSTRACT FROM AUTHOR]

The objective of the present paper is to provide a holistic framework to delineate 'territories of opportunity' where agrarian communities can manage areas to enhance the conservation of large vertebrates. The study was conducted Mexico, which is sociologically, culturally and ecologically complex, similar to other 'megadiverse' countries. We conducted ensemble niche modeling of endangered top predators to define a set of large vertebrate species. Environmental attributes were used to perform three distance-based and two artificial intelligence-based algorithms. Socio-cultural attributes were included to depict agricultural communities with strong social government schemes and clear evidence of well-managed natural resources. Other socio-economic attributes such as land acquisition cost, human agglomeration and anthropogenic land use were included in the analysis. Scenarios were computed and displayed cartographically with the aid of a geographic information system. Results showed that the largest concentration of biodiversity converges on regions with large land cover persistence and high local governance, defined as potential willingness to engage in conservation actions. The cartographic areas identified overlapped with current Mexican protected areas in only 2.7% of the country. Thus, conservation law enforcement in most of the country seems to be ineffective. Here we show that, in a number of territories, agrarian communities that have coexisted for millennia with umbrella species can be regarded as allies in biodiversity conservation. Results are discussed in the light of their relevance for future niche modeling, environmental policy design and implications for climate change. [ABSTRACT FROM AUTHOR]

Human activities are affecting the distribution of species worldwide by causing fragmentation and isolation of populations. Isolation and fragmentation lead to populations with lower genetic variability and an increased chance of inbreeding and genetic drift, which results in a loss of biological fitness over time. Studies of the genetic structure of small and isolated populations are critically important for management and conservation decisions. Ambystoma rivulare is a micro-endemic Mexican mole salamander from central Mexico. It is found in the most ecologically disturbed region in Mexico, the Trans-Mexican Volcanic Belt. The goal of this study of the population genetics of the micro-endemic mole salamander was to provide information to be used as a basis for future research and conservation planning of this species and other species of the Ambystoma genus in Mexico. The structural analysis found two subpopulations, one for each river sampled, with no signs of admixture and very high levels of genetic differentiation. Medium to high levels of heterozygosity and few alleles and genotypes were observed. Evidence of an ancestral genetic bottleneck, low values of effective population size, small inbreeding coefficients, and low gene flow were also found. [ABSTRACT FROM AUTHOR]

Nesting of the American crocodile (Crocodylus acutus) is affected by natural and anthropogenic processes. In Mexico, few studies exist on reproductive traits of wild populations. We assessed the key reproductive characteristics of C. acutus in the La Encrucijada biosphere reserve and the environmental and anthropogenic factors that influence them. From February to June 2014, we searched for nests in the reserve. Clutch incubation temperature was recorded by data loggers and climatic variables were obtained from La Encrucijada meteorological station. Additionally, outside the study area, net primary productivity was obtained for different sites in Mexico to relate it to clutch characteristics. We found 34 nests in nine nesting areas. Egg laying occurred in March, and hatching took place from mid-May to early June. Mean clutch and eggs characteristics are among the higher reported for C. acutus. Some egg attributes had a relationship with the net primary productivity. There was no relation between hatching success and external and internal characteristics of the nest. A high percentage of nests was poached (50%) mainly for egg consumption and fear of crocodiles, and the nests closer to the river, trees or human settlements are more likely to be poached. [ABSTRACT FROM AUTHOR]

Genealogical records of animals (studbook) are created to avoid reproduction between closely related individuals, which could cause inbreeding, particularly for such endangered species as the Panthera onca (Linnaeus, 1758). Jaguar is the largest felid in the Americas and is considered an important ecological key species. In Mexico, wild jaguar populations have been significantly reduced in recent decades, and population decline typically accompany decreases in genetic variation. There is no current census of captive jaguars in Mexico, and zoos do not follow a standardized protocol in breeding programs based on genetic studies. Here, we emphasise the importance of maintaining an adequate level of genetic variation and propose the implementation of standardised studbooks for jaguars in Mexico, mainly to avoid inbreeding. In addition, achieving the aims of studbook registration would provide a population genetic characterisation that could serve as a basis for ex situ conservation programmes. [ABSTRACT FROM AUTHOR]

Predator-prey dynamics are primarily determined by the predator's ability to hunt and the prey's strategies to avoid it. This dynamic can be influenced by ecological, environmental or anthropogenic factors. We analyzed the activity pattern of puma (Puma concolor) and its main prey species, armadillo (Dasypus novemcinctus), coati (Nasua narica) and white-tailed deer (Odocoileus virginianus) by means of photographic records. The pattern of activity of the predator species is not distributed uniformly throughout the day. No dependence of the activity pattern of the species on the moon phase was found. In addition, a statistically significant relationship between the activity pattern of puma and its main prey (armadillo) was obtained. [ABSTRACT FROM AUTHOR]

It is necessary to determine genetic diversity of fragmented populations in highly modified landscapes to understand how populations respond to land-use change. This information will help guide future conservation and management strategies. We conducted a population genetic study on an endemic Mexican Dusky Rattlesnake ( Crotalus triseriatus) in a highly modified landscape near the Toluca metropolitan area, in order to provide crucial information for the conservation of this species. There was medium levels of genetic diversity, with a few alleles and genotypes. We identified three genetically differentiated clusters, likely as a result of different habitat cover type. We also found evidence of an ancestral genetic bottleneck and medium values of effective population size. Inbreeding coefficients were low and there was a moderate gene flow. Our results can be used as a basis for future research and C. triseriatus conservation efforts, particularly considering that the Trans-Mexican Volcanic Belt is heavily impacted by destructive land-use practices. [ABSTRACT FROM AUTHOR]

White-tailed deer ( Odocoileus virginianus) are economically important in the Americas and are also the main prey of predators such as the jaguar ( Panthera onca) and puma ( Puma concolor), but human influence has led to the decline of their populations by hunting and increasing agricultural and pastoral land use. On the other hand, there is a lack of ecological knowledge on the species in central Mexico. We investigated the population density and activity pattern of white-tailed deer in the Sierra Nanchititla, Mexico, using 10 camera traps. Sampling was conducted over 18 months between 2004 and 2007. We identified deer in photographs, and the population abundance was estimated using the CAPTURE program and density by dividing the estimated abundance by the effective sampled area. The daily activity pattern was derived by using the recorded time in the photographs for each hour of the day. Population density was from 2.0 to 6.3 in the wet season and 0.8-12 individuals/km2 in the dry, showing a diurnal pattern. This study was one of the first using camera traps in Mexico, for a sampling period longer than 1 year and provided information for the development of management programs. [ABSTRACT FROM AUTHOR]

The article discusses a study on the mechanisms underpinning the coexistence among terrestrial carnivore predators at a temperate zone in central Mexico. Topics covered include a high dietary overlap within predator guilds, resource partitioning between guilds, and the effect of body size, morphology and prey segregation on carnivore coexistence. Also mentioned are the characteristics of the top predators Puma concolor and Panthera onca and mesopredators such as Leopardus pardalis.

The reduced immigration and emigration rates resulting from the lack of landscape connectivity of patches and the hospitality of the intervening matrix could favor the loss of alleles through genetic drift and an increased chance of inbreeding. In order for isolated populations to maintain sufficient levels of genetic diversity and adapt to environmental changes, one important conservation goal must be to preserve or reestablish connectivity among patches in a fragmented landscape. We studied the last known population of Ambystoma leorae, an endemic and critically threatened species. The aims of this study were: (1) to assess the demographic parameters of A. leorae and to distinguish and characterize the microhabitats in the river, (2) to determine the number of existing genetic groups or demes of A. leorae and to describe possible relationships between microhabitats types and demes, (3) to determine gene flow between demes, and (4) to search for geographic locations of genetic discontinuities that limit gene flow between demes. We found three types of microhabitats and three genetically differentiated subpopulations with a significant level of genetic structure. In addition, we found slight genetic barriers. Our results suggest that mole salamander’s species are very sensitive to microhabitat features and relatively narrow obstacles in their path. The estimates of bidirectional gene flow are consistent with the pattern of a stepping stone model between demes, where migration occurs between adjacent demes, but there is low gene flow between distant demes. We can also conclude that there is a positive correlation between microhabitats and genetic structure in this population. [ABSTRACT FROM AUTHOR]

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Small or isolated populations are highly susceptible to stochastic events. They are prone and vulnerable to random demographic or environmental fluctuations that could lead to extinction due to the loss of alleles through genetic drift and increased inbreeding. We studied Ambystoma leorae an endemic and critically threatened species. We analyzed the genetic diversity and structure, effective population size, presence of bottlenecks and inbreeding coefficient of 96 individuals based on nine microsatellite loci. We found high levels of genetic diversity expressed as heterozygosity (H = 0.804, H = 0.613, H = 0.626 and H = 0.622). The population presents few alleles (4-9 per locus) and genotypes (3-14 per locus) compared with other mole salamanders species. We identified three genetically differentiated subpopulations with a significant level of genetic structure (F = 0.021, R = 0.044 y D = 0.010, 95 % CI). We also detected a reduction signal in population size and evidence of a genetic bottleneck (M = 0.367). The effective population size is small (Ne = 45.2), but similar to another mole salamanders with restricted distributions or with recently fragmented habitat. The inbreeding coefficient levels detected are low (F = −0.619-0.102) as is gene flow. Despite, high levels of genetic diversity A. leorae is critically endangered because it is a small isolated population. [ABSTRACT FROM AUTHOR]

The article presents a study which evaluates the association between the spatial factors and management with the livestock predations by Puma concolor in Central Mexico. The study uses the linear regressions to identify the variables which are best predicted predation risk. Results show that the risk of injury to pumas is reduced by the predation selection for goats and the livestock vulnerability was increased by the lack of night shelter in relation to the nocturnal habitats of the animal.

The composition and energetic content of puma (Puma concolor) diet in Sierra Nanchititla Natural Reserve (SNNR), Mexico, were determined. We collected 183 scats, where 27 components were identified by occurrence (88.07% mammals). The puma's diet was mainly composed of armadillo (Dasypus novemcinctus, 40.33%), white-nosed coati (Nasua narica, 11.93%) and white-tailed deer (Odocoileus virginianus, 6.17%). Energetic analysis of prey indicates that the puma prefers those with higher energetic content (kcal/kg). The prey with the most energetic contribution is armadillo (2398.70 kcal/kg), followed by white-nosed coati (2225.25 kcal/kg) and finally white-tailed deer (2165.52 kcal/kg). The differences in energetic content between prey species were statistically significant. The number of individuals killed/year on average to support a puma was 51 armadillos, 16 white-tailed deer and 7 white-nosed coatis. The results indicate a greater consumption of prey that provide more kilocalories to the predator, and suggests the importance of quality meat in the diet of pumas. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The jaguar, Panthera onca, is a species of global conservation concern. In Mexico, the northernmost part of its distribution range, its conservation status, is particularly critical, while its potential and actual distribution is poorly known. We propose an ensemble model (EM) of the potential distribution for the jaguar in Mexico and identify the priority areas for conservation. Mexico. We generated our EM based on three presence-only methods (Ecological Niche Factor Analysis, Mahalanobis distance, Maxent) and considering environmental, biological and anthropogenic factors. We used this model to evaluate the efficacy of the existing Mexican protected areas (PAs), to evaluate the adequacy of the jaguar conservation units (JCUs) and to propose new areas that should be considered for conservation and management of the species in Mexico. Our results outline that 16% of Mexico ( c. 312,000 km) can be considered as suitable for the presence of the jaguar. Furthermore, 13% of the suitable areas are included in existing PAs and 14% are included in JCUs (). Clearly much more should be carried out to establish a proactive conservation strategy. Based on our results, we propose here new jaguar conservation and management areas that are important for a nationwide conservation blueprint. [ABSTRACT FROM AUTHOR]

Little is known about the status of Puma concolor populations in Central and South America. Due to this reason, the present study contributes to the knowledge on puma populations providing information on abundance and density in Sierra Nanchititla, Mexico, as well as comparing recorded values against those obtained from zones of high and low concentration of camera traps. The sampling was carried out during a period of 30 months, which were divided into 3-month independent blocks. For the 8 first blocks, ten camera traps were set in an area where the separation among cameras was 1.6 km, and in the 2 last blocks 17 camera traps were set in an area where the separation was 4.6 km. The abundance was estimated between 2 and 5 individuals for the area with the highest concentration of cameras, lower than the abundance obtained in the area with the lowest concentration of cameras, i.e., 6 individuals. The density of the area with the highest camera concentration had a variation between 2.74 and 6.86 individuals/100 km2 in an effective survey area of 72.8 km2 and for the area of lowest concentration it was 1.21 individual/100 km2 in an effective survey area of 492.6 km2. [ABSTRACT FROM AUTHOR]

In this study the habitat use and activity patterns of the two of the largest cats of the Americas in central Mexico were studied. Three ways to detect felid presence were employed from August 2002 to May 2006: interviews, signs, and camera-traps. 478 records were obtained, from which 441 were from cougar and 37 from jaguar. These records included positive response in 118 of 140 interviews and 236 records of signs (mainly tracks and scats), and 124 photographs. Both felids preferred pine-oak forest habitats, with altitudes higher than 1800 m, distances between 3509 and 4377 m from roads, between 2329 and 4650 m from settlements, and distances to very steep slopes between 1048 and 2059 m, for jaguar, and for cougar lower than 1047 m. Jaguar activity was recorded mainly during nighttimes, between 0:00 and 6:00, whereas cougar was active between 4:00 and 6:00 and between 18:00 and 22:00 hours, avoiding the jaguar's principal activity period. [ABSTRACT FROM AUTHOR]

This article discusses a study which aimed to determine the food habits of the puma, Puma concolor, in the Sierra Nanchititla, Central Mexico. Researchers observed that the puma tends to prey on large mammals, the nine-banded armadillo, Dasypus novemcinctus, being its main prey. The results also revealed that the puma preys on the white-nosed coati, Nasua narica, and white-tailed deer, Odocoileus virginianus. In addition, the study showed that the food preferences of puma in Central Mexico resemble those recorded for puma in South America.

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The field of movement ecology has rapidly grown during the last decade, with important advancements in tracking devices and analytical tools that have provided unprecedented insights into where, when, and why species move across a landscape. Although there has been an increasing emphasis on making animal movement data publicly available, there has also been a conspicuous dearth in the availability of such data on large carnivores. Globally, large predators are of conservation concern. However, due to their secretive behavior and low densities, obtaining movement data on apex predators is expensive and logistically challenging. Consequently, the relatively small sample sizes typical of large carnivore movement studies may limit insights into the ecology and behavior of these elusive predators. The aim of this initiative is to make available to the conservation‐scientific community a dataset of 134,690 locations of jaguars (Panthera onca) collected from 117 individuals (54 males and 63 females) tracked by GPS technology. Individual jaguars were monitored in five different range countries representing a large portion of the species’ distribution. This dataset may be used to answer a variety of ecological questions including but not limited to: improved models of connectivity from local to continental scales; the use of natural or human‐modified landscapes by jaguars; movement behavior of jaguars in regions not represented in this dataset; intraspecific interactions; and predator‐prey interactions. In making our dataset publicly available, we hope to motivate other research groups to do the same in the near future. Specifically, we aim to help inform a better understanding of jaguar movement ecology with applications towards effective decision making and maximizing long‐term conservation efforts for this ecologically important species. There are no costs, copyright, or proprietary restrictions associated with this data set. When using this data set, please cite this article to recognize the effort involved in gathering and collating the data and the willingness of the authors to make it publicly available. [ABSTRACT FROM AUTHOR]