Molecular Detection of Dengue Virus, Zika Virus, and Chikungunya Virus Arboviruses in Neotropical Bats.

Background: The dengue, Zika, and Chikungunya arboviruses have spread in America in the past year, thus becoming global health issues. These viruses are maintained in nature in two transmission cycles: an urban cycle, transmitted from hematophagous mosquitoes to humans, and a wild cycle, recorded only in Africa and Asia, involving mosquitoes and nonhuman primates as natural hosts. The evidence shows that these arboviruses infect other wild mammals in America, such as rodents, marsupials, and bats. This study aimed to determine the potential natural infection of arboviruses in bats captured in contrasting sites (tropical forests, urban areas, and caves) in Oaxaca, Mexico. Materials and Methods: Liver samples were collected from some bats and tested for RNA from dengue, Zika, and Chikungunya with the quantitative real-time PCR assay. We analyzed 162 samples that encompassed 23 bat species. Results: No natural infection with any of the three arboviruses was detected in any sample tested. Conclusion: The existence of a wild cycle of the three arboviruses in the American continent is not ruled out. However, owing to the low or zero prevalence recorded in other studies and the present study, bats are likely involved in the arbovirus transmission cycle as accidental hosts.

Coronaviruses in Bats: A Review for the Americas.

The SARS-CoV-2 coronavirus is the focus of attention as it has caused more than three million human deaths globally. This and other coronaviruses, such as MERS-CoV, have been suggested to be related to coronaviruses that are hosted in bats. This work shows, through a bibliographic review, the frequency of detection of coronavirus in bats species of the Americas. The presence of coronavirus in bats has been examined in 25 investigations in 11 countries of the Americas between 2007 and 2020. Coronaviruses have been explored in 9371 individuals from 160 species of bats, and 187 coronavirus sequences have been deposited in GenBank distributed in 43 species of bats. While 91% of the coronaviruses sequences identified infect a single species of bat, the remainder show a change of host, dominating the intragenera change. So far, only Mex-CoV-6 is related to MERS-CoV, a coronavirus pathogenic for humans, so further coronavirus research effort in yet unexplored bat species is warranted.

Current Knowledge and Ecological and Human Impact Variables Involved in the Distribution of the Dengue Virus by Bats in the Americas.

Dengue fever, caused by the dengue virus (DENV), is one of the most important reemerging viral diseases transmitted by arthropods worldwide. DENV is maintained in nature in two transmission cycles: urban and sylvatic. The latter has only been recorded in Africa and Asia and involves nonhuman primates as natural hosts, although it has been suggested that other mammals may play a secondary role as potential reservoir host, including bats. The objective of this article is to review the current state of knowledge about DENV-positive bats in the Americas and to determine what ecological and human impact variables could favor DENV infection in bats. We performed a search of published studies on natural and experimental DENV infection in bats. From 1952 to 2019, 14 studies have been carried out (71.4% in the last decade) examining DENV infection in bats in seven countries of the Americas. DENV infection was examined in 1884 bats of 63 species and DENV was detected in 19 of these species. Clench's model estimated that more than 75 species could be carriers of DENV; therefore, considering that at least 350 species of bats are distributed in the Americas, to detect 95% of the DENV-bearing species, it would be necessary to examine about 10,206 bats of ∼287 species that have not been analyzed until 2019. The species with the highest number of positive cases were Molossus sinaloae and Artibeus jamaicensis. Species, colony size, mean annual temperature, mean annual precipitation, human population size, and bat collection site (site inhabited by humans, vegetation cover, and caves) contributed to explain the variation in DENV detection in bats in the Americas. These results provide evidence on the exposure of bats to DENV in different geographic areas of the Americas and a bat sylvatic transmission cycle is very likely to be occurring, where bats may be either accidental hosts, dead-end hosts, or potential reservoir hosts for DENV.

Estimation of bat colony size even with low recapture rates: an example based on the Cormack-Jolly-Seber model in Oaxaca, México / Estimación del tamaño de colonia en murciélagos incluso con bajas tasas de recaptura: un ejemplo basado en el modelo Cormack-Jolly-Seber en Oaxaca, México

Introduction: Group or colony size is an important variable that is related to biological, ecological, and conservation aspects of bats. However, estimating the size of each colony or group in roosts used by more than one species is particularly difficult, especially when recapture rates are very low (< 10 %). Objective: Estimate the colony size of 14 species of bats: one emballonurid, one natalid, four mormoopids, seven phyllostomids, and one vespertilionid, which roosted throughout one year (July 2016 to June 2017) in a mine and two caves -Cerro Huatulco and El Apanguito- in the Sierra Sur and Costa of the state of Oaxaca. Methods: We constructed capture-recapture histories per species and roost, and for species for which we obtained recaptures that represented at least 10 % of the captures, we used the probabilistic Cormack-Jolly-Seber model. In the case of species with no recaptures or with a recapture proportion lower than 10 %, we estimated the number of individuals per roost by applying the same proportion between the number of captured specimens and the estimated number for species with recaptures greater than 10 % and that they belonged to the same family or trophic guild. Results: The total estimated number of bats in the three studied roosts was 20 105. The highest colony size estimates were for the mormoopids Pteronotus fulvus and P. mesoamericanus from El Apanguito and P. fulvus from Cerro Huatulco, with 6 609, 4 092 and 2 212 individuals, respectively. Conclusions: The methodology used in this study allowed estimating the colony size for all registered species, even though only for 21.42 % the recapture rates were greater than 10 %. Therefore, we consider that this methodology represents a viable alternative to estimate colony size in other roosts. This information, together with the high species richness and importance for reproductive processes, allow us to propose these sites as Bat Protection and Conservation Areas in Mexico.

Introducción: El tamaño del grupo o colonia es una variable importante que está relacionada con los aspectos biológicos, ecológicos y de conservación de los murciélagos. Sin embargo, estimar el tamaño de cada colonia o grupo en refugios utilizados por más de una especie es particularmente difícil, especialmente cuando las tasas de recaptura son muy bajas (< 10 %). Objetivo: Estimar el tamaño de la colonia de 14 especies de murciélagos: un emballonúrido, un natálido, cuatro mormópidos, siete filostómidos y un vespertiliónido, que se refugiaron durante un año (Julio 2016 a Junio 2017) en una mina y dos cuevas -Cerro Huatulco y El Apanguito- en la Sierra Sur y Costa del estado de Oaxaca. Métodos: Construimos historias de captura-recaptura por especie y refugio, y para las especies que se obtuvieron recapturas que representaban al menos el 10 % de las capturas, utilizamos un modelo probabilístico de Cormack-Jolly-Seber para estimar el tamaño de sus colonias. En el caso de especies sin recapturas o con una proporción de recaptura inferior al 10 %, estimamos el número de individuos por refugio aplicando la misma proporción entre el número de individuos capturados y el número total estimado para las especies con recapturas mayores del 10 % y que pertenecieran a la misma familia o gremio trófico registradas con la mayor similitud ecológica y con suficientes recapturas para aplicar el modelo Cormack-Jolly-Seber. Resultados: El número total estimado de murciélagos en los tres refugios de estudio fue de 20 105. Las estimaciones de tamaño de colonia más altos fueron para los mormópidos Pteronotus fulvus y P. mesoamericanus de El Apanguito y P. fulvus en Cerro Huatulco, con 6 609, 4 092 and 2 212 individuos, respectivamente. Conclusiones: La metodología utilizada en este estudio permitió estimar el tamaño de la colonia para todas las especies registradas, a pesar de que solo para el 21.42 % las tasas de recaptura fueron superiores al 10 %. Por lo tanto, consideramos que esta metodología representa una alternativa viable para estimar el tamaño de colonia en otros refugios. Esta información, junto con los procesos de alta riqueza de especies y reproducción que tienen lugar en esta área, permiten proponer estos sitios como áreas de protección y conservación de murciélagos en México.

Reproduction and population dynamics of cave-dwelling bats in Costa of Oaxaca, México

Introduction: Reproduction is a critical phase for most living organisms and in bats the reproductive strategies exhibit considerable complexity and variability. Objective: To describe the reproductive patterns and population dynamics of seven bat species (Artibeus toltecus, Carollia perspicillata, Glossophaga soricina, Mormoops megalophylla, Pteronotus fulvus, Pteronotus mesoamericanus and Natalus mexicanus) that roost in one mine (La Mina) and two caves (El Apanguito and Cerro Huatulco) in the State of Oaxaca, in Southeastern México. Methods: Sampling was conducted monthly from July 2016 to June 2017. Bats were captured using a harp trap, which was placed at the entrance of the roosts. The captured bats were identified using taxonomic keys, marked with an aluminum ring, sex and age class were also determined. Reproductive activity was modeled through 63 GLMs for each species (504 in total). The best model was selected according to the Akaike Information Criterion (AIC). Results: A total of 5 836 bats were captured and marked, classified into 14 species, 10 genera, and five families. The most abundant species were: P. fulvus and P. mesoamericanus, representing 41 % and 32.3 % of the captures, respectively. The mormopids M. megalophylla, P. fulvus, P. mesoamericanus,together with N. mexicanus showed a restricted seasonal monoestrous pattern, while the phyllostomids A. toltecus, C. perspicillata, and G. soricina showed a seasonal bimodal polyoestry pattern. The monthly abundance of species fluctuated significantly (H= 13, df= 11, P= 0.044) in the three roosts throughout the entire study period and the best supported GLM that included the seven species showed that the six chosen variables (season, sex, roost, temperature, precipitation and humidity) were positively associated with reproductive activity. Conclusions: The reproductive activity of each species seems to be synchronized with the end of the dry season and the beginning of the rainy season, as well as influenced by factors such as temperature, humidity and roost site.

Introducción: La reproducción es una fase crítica para la mayoría de los organismos vivos y en los murciélagos las estrategias reproductivas exhiben considerable complejidad y variabilidad. Objetivo: Describir los patrones reproductivos y la dinámica poblacional de siete especies de murciélagos: Artibeus toltecus, Carollia perspicillata, Glossophaga soricina, Mormoops megalophylla, Pteronotus fulvus, Pteronotus mesoamericanus y Natalus mexicanus, que se refugian en una mina (La Mina) y dos cuevas (El Apanguito y Cerro Huatulco), en el estado de Oaxaca, sureste de México. Métodos: El muestreo se realizó una vez al mes de julio 2016 a junio 2017. Los murciélagos se capturaron utilizando una trampa de arpa que fue colocada en la entrada de los refugios. La especie de los murciélagos capturados fue determinada con claves de identificación taxonómica, además fueron marcados con un anillo de aluminio y también se determinó el sexo y la clase de edad. La actividad reproductiva fue modelada a través de 63 GLMs para cada especie (504 en total). El mejor modelo fue seleccionado según el Criterio de Información de Akaike (AIC). Resultados: Se capturaron y marcaron 5 836 murciélagos, incluidos en 14 especies, 10 géneros y cinco familias. Las especies más abundantes fueron: P. fulvus y P. mesoamericanus, que representaron el 41 y el 32.3 % de las capturas, respectivamente. Los mormópidos M. megalophylla, P. fulvus, P. mesoamericanus junto con N. mexicanus mostraron un patrón monoéstrico estacional,mientras que los filostómidos A. toltecus, C. perspicillata y G. soricina mostraron un patrón poliéstrico estacional bimodal. La abundancia mensual de las especies fluctuó significativamente (H= 13, df= 11, P= 0.044) en los tres refugios a lo largo del periodo de estudio y el GLM mejor respaldado que incluyó las siete especies mostró que las seis variables elegidas (temporada, sexo, refugio, temperatura, precipitación y humedad) se asociaron positivamente con la actividad reproductiva. Conclusiones: La actividad reproductiva de cada especie parece estar sincronizada con el final de la temporada seca y el comienzo de la temporada de lluvias, e influenciada por factores como temperatura, humedad y el sitio de refugio.

Densidad, idoneidad ambiental y nicho ecológico de cuatro especies de felinos americanos (Carnivora: Felidae)

Varias de las especies silvestres de la familia Felidae se encuentran en riesgo y el tamaño poblacional es uno de los parámetros ecológicos más importantes para determinar acciones efectivas de conservación. El tamaño poblacional está determinado por diferentes factores, tanto bióticos como abióticos, que en conjunto satisfacen los requerimientos de los individuos para sobrevivir y reproducirse, permitiendo la permanencia de las especies a través del tiempo. Debido a que el tamaño poblacional de una especie no es homogéneo a lo largo de su distribución, se han formulado varias hipótesis para explicar sus variaciones. Una propuesta considera que las poblaciones más grandes se ubican en las regiones con mayor idoneidad ambiental y el número de individuos decrece hacia las menos favorables. Otra hipótesis considera que el tamaño poblacional está relacionado con la estructura interna del nicho ecológico, en donde las poblaciones más grandes están ubicadas en el centroide del nicho y el tamaño declina conforme aumenta la distancia a éste. El objetivo de este estudio fue evaluar la relación de la abundancia poblacional con la idoneidad ambiental y el nicho ecológico en cuatro especies de felinos silvestres de América. La densidad de Lynx rufus (lince) se correlacionó positivamente con el índice de idoneidad ambiental, la mayor densidad de Panthera onca (jaguar) se ubicó en regiones cercanas al centroide del nicho, mientras que las densidades poblacionales de Leopardus pardalis (ocelote) y de Puma concolor (puma) no se ajustaron a las predicciones de ninguna de las dos hipótesis. La relación entre densidad de felinos con las características ambientales puede ser especie-específica y no seguir un patrón generalizado.

Several wild species of the family Felidae are at risk, and population size is one of the most important ecological parameters to determine conservation actions. Population size is influenced by different biotic and abiotic factors that satisfy the requirements of the species to survive and reproduce, allowing the permanence of the species through time. Because population size is not homogeneous throughout the distribution, there are several hypotheses to explain their variations. One proposal considers that more abundant populations are located in regions with environmentally suitability, and population size decreases towards the less favorable ones. Another hypothesis considers that the population size is related to the internal structure of the ecological niche, where the largest populations are located in the centroid of the niche, and the size declines as the distance to this centroid increase. The objective of this study was to evaluate the relationship between population abundance, environmental suitability and ecological niche in four wild felids species of America. The density of Lynx rufus (bobcat) was correlated positively with the environmental suitability index, the highest density of Panthera onca (jaguar) was located in regions near the centroid of the niche, while the population densities of Leopardus pardalis (ocelot) and Puma concolor (cougar) did not conform to the predictions of either of the two hypotheses. The relationship between feline density and environmental characteristics was species-specific, with no general pattern.

Efecto del manejo forestal en la herpetofauna de un bosque templado del occidente de Oaxaca, México / Effect of forest management on the herpetofauna of a temperate forest of western Oaxaca, Mexico

ResumenEl desarrollo de técnicas y tratamientos silvícolas tiene como objetivo principal el aumento de la productividad forestal, al mismo tiempo que minimiza el impacto sobre la diversidad. A pesar de ello, estas actividades modifican la estructura de la vegetación, así como el clima local, alterando la composición de las comunidades. El efecto de estos cambios puede ser mayor en aquellos grupos taxonómicos con alta sensibilidad a las alteraciones del hábitat, como es el caso de los anfibios y reptiles, que al ser los únicos vertebrados terrestres ectotermos, pueden verse seriamente afectados por las variaciones de clima local. El presente trabajo tiene como objetivo conocer las diferencias en diversidad de anfibios y reptiles en un bosque templado bajo dos tratamientos silvícolas (uno intensivo y otro de baja intensidad) y con diferentes tiempos de regeneración (uno, cinco y diez años) en la Sierra Sur del estado de Oaxaca, México. Se obtuvieron registros de 21 especies de herpetofauna (seis anfibios y 15 reptiles). La riqueza total de especies fue similar en ambos tratamientos; sin embargo, la composición varió entre sitios con diferentes tiempos de recuperación. La mayor abundancia de anfibios se presentó en los sitios con el tratamiento de baja intensidad, mientras que los reptiles fueron más abundantes en los sitios con el tratamiento intensivo. Se observó un mayor número de especies raras en los sitios intervenidos con el tratamiento intensivo, aunque los valores de diversidad verdadera de anfibios fueron similares entre tratamientos con intensidades diferentes, mientras que en los reptiles se observó una diversidad 33 % menor en los sitios bajo el tratamiento intensivo y un 28 % en los sitios con baja intensidad respecto al sitio control. Un Análisis de Complementariedad mostró una diferencia de hasta 86 % de disimilitud entre la composición de especies en sitios con el tratamiento intensivo. La intensidad del tratamiento estuvo asociada con un aumento en el número de especies, sin embargo la manera en que responden ante las modificaciones de hábitat depende en gran medida de las características poblacionales de cada especie, así como su habilidad de adaptación a las nuevas condiciones del hábitat.

Abstract:The development of silvicultural techniques has as main objective to maximize the production of timber, whereas at the same time minimize the impact generated during and after forest intervention in the local diversity. However, these activities change local climate, and this, in turn, alter the composition of natural communities. The effect of these changes may be greater in those taxonomic groups with high sensitivity to habitat disturbance, such as amphibians and reptiles, which are the unique terrestrial ectothermic vertebrates. The present study aims to know the differences in diversity of amphibians and reptiles in a temperate forest under two silvicultural treatments, one of low and the other of high intensity, as well as from one, five and ten years of regeneration since the last logging event, Sierra Sur of Oaxaca, Mexico. Records of 21 species of herpetofauna (six amphibians and 15 reptiles) were obtained. The total species richness was similar in both treatments; however, the composition varied between sites with different recovery times. Higher abundance of amphibian was presented on sites with the low-intensity treatment, while reptiles were more abundant at sites with intensive treatment. Compared to a mature forest without management, sites with intensive treatment have more rare species, although the values of true diversity of amphibians were similar between treatments with different intensities, while for reptiles sites under treatment showed less diversity that unmanaged site: 33 % for intensive treatment and 28 % at sites with low intensity with respect to one control site. Complementary Analysis showed a difference of 86 % between the compositions of species in sites with intensive treatment. The treatment intensity was associated with an increase in the number of species, but the way they respond to changes in habitat depends largely on the population characteristics of each species and its ability to adapt to new conditions. Rev. Biol. Trop. 64 (3): 931-943. Epub 2016 September 01.

[Effect of forest management on the herpetofauna of a temperate forest of western Oaxaca, Mexico]. / Efecto del manejo forestal en la herpetofauna de un bosque templado del occidente de Oaxaca, México.

The development of silvicultural techniques has as main objective to maximize the production of timber, whereas at the same time minimize the impact generated during and after forest intervention in the local diversity. However, these activities change local climate, and this, in turn, alter the composition of natural communities. The effect of these changes may be greater in those taxonomic groups with high sensitivity to habitat disturbance, such as amphibians and reptiles, which are the unique terrestrial ectothermic vertebrates. The present study aims to know the differences in diversity of amphibians and reptiles in a temperate forest under two silvicultural treatments, one of low and the other of high intensity, as well as from one, five and ten years of regeneration since the last logging event, Sierra Sur of Oaxaca, Mexico. Records of 21 species of herpetofauna (six amphibians and 15 reptiles) were obtained. The total species richness was similar in both treatments; however, the composition varied between sites with different recovery times. Higher abundance of amphibian was presented on sites with the low-intensity treatment, while reptiles were more abundant at sites with intensive treatment. Compared to a mature forest without management, sites with intensive treatment have more rare species, although the values of true diversity of amphibians were similar between treatments with different intensities, while for reptiles sites under treatment showed less diversity that unmanaged site: 33 % for intensive treatment and 28 % at sites with low intensity with respect to one control site. Complementary Analysis showed a difference of 86 % between the compositions of species in sites with intensive treatment. The treatment intensity was associated with an increase in the number of species, but the way they respond to changes in habitat depends largely on the population characteristics of each species and its ability to adapt to new conditions.

Density, distribution, and activity of the ocelot Leopardus pardalis (Carnivora: Felidae) in Southeast Mexican rainforests / Densidad, distribución y actividad del ocelote Leopardus pardalis (Carnivora: Felidae) en los bosques húmedos del sureste mexicano

The ocelot Leopardus pardalis is of particular significance in terrestrial communities due to its ecological role within the group of small-sized felids and as a mesopredator. However, despite the reduction of ocelot habitat in Southeast Mexico, there are still very few ecological studies. This research aimed to contribute with some ecological aspects of the species in this region. For this, 29 camera trap stations were established in a rain forest in Los Chimalapas (an area of 22km2) during a two years period (March 2011-June, 2013), in Oaxaca state, Southeast Mexico. Data allowed the estimation of the population density, activity pattern, sex ratio, residence time, and spatial distribution. Population density was calculated using Capture-Recapture Models for demographically open populations; besides, circular techniques were used to determine if nocturnal and diurnal activity varied significantly over the seasons, and Multiple Discriminant Analysis was used to determine which of the selected environmental variables best explained ocelot abundance in the region. A total of 103 ocelot records were obtained, with a total sampling effort of 8 529 trap-days. Density of 22-38individuals/100km2 was estimated. Ocelot population had a high proportion of transient individuals in the zone (55%), and the sex ratio was statistically equal to 1:1. Ocelot activity was more frequent at night (1:00-6:00h), but it also exhibited diurnal activity throughout the study period. Ocelot spatial distribution was positively affected by the proximity to the village as well as by the amount of prey. The ocelot population here appears to be stable, with a density similar to other regions in Central and South America, which could be attributed to the diversity of prey species and a low degree of disturbance in Los Chimalapas. Rev. Biol. Trop. 62 (4): 1421-1432. Epub 2014 December 01.

El ocelote Leopardus pardalis es importante en comunidades terrestres debido a su papel ecológico dentro del grupo de felinos de tallas pequeñas y como mesodepredador. A pesar de la disminución del hábitat del ocelote en el sureste de México, son pocos los estudios ecológicos. El siguiente trabajo presenta una contribución de algunos aspectos ecológicos de la especie en esta región. Se estimó la densidad poblacional, patrón de actividad, proporción de sexos, tiempo de residencia y distribución espacial del ocelote. El estudio se llevó a cabo mediante fototrampeo dentro de Los Chimalapas, en el estado de Oaxaca, sureste de México. Se establecieron 29 estaciones dentro de la selva alta y se cubrió un área de 22km2, durante dos años (marzo 2011-junio 2013). La densidad fue estimada usando Modelos de Captura-Recaptura para poblaciones demográficamente abiertas, las técnicas circulares fueron usadas para determinar si la actividad nocturna y diurna varió significativamente entre épocas y, un análisis discriminante múltiple fue usado para conocer cuáles variables explican mejor la abundancia del ocelote en la región. Se obtuvieron 103 registros de ocelote con un esfuerzo de 8 529 días-trampa. Se estimó una densidad de 22-38 individuos/100km2. La población del ocelote tuvo un porcentaje alto de transeúntes (55%) y la proporción de sexos fue estadísticamente similar de 1:1. El ocelote estuvo más activo en la noche (1:00-6:00am), pero exhibió actividad diurna durante todo el periodo de estudio. La distribución espacial estuvo afectada positivamente por la proximidad a poblados y por la cantidad de presas. La población del ocelote parece estable, con una densidad similar a otras regiones de Centro y Sudamérica, quizá debido a la diversidad de especies presa y al grado bajo de alteración en Los Chimalapas.

[Effects of landscape and vegetation structure on the diversity of phyllostomid bats (Chiroptera: Phyllostomidae) in Oaxaca, Mexico]. / Efectos de la estructura del paisaje y de la vegetación en la diversidad de murciélagos filostómidos (Chiroptera: Phyllostomidae) de Oaxaca, México.

The tropical forest fragmentation is known to affect the spatial structure of the landscape and habitat. These alterations can modify the attributes of bat assemblages, however, this phenomenon has been little studied and understood. In this work we evaluated the structure of landscape (i.e. composition and configuration) and vegetation, and its relationship with assemblage- and population-level characteristics of phyllostomid bats in a tropical rainforest of Southeastern Mexico. For this, we previously selected 12 sites located in continuous and fragmented forests, where bats were captured using mist nets during a two years sampling effort (144 nights). Bats relative abundance, species richness (diversity of order 0, 0D), Shannon diversity index (1D) and Simpson index (2D) were evaluated in all sites, and their relationship with seven measures of landscape structure and seven measures of vegetation structure was described using a Hierarchical Partitioning Analysis. A total of 1 840 individuals of 29 species of phyllostomid bats were captured in this period. Differences in the assemblages were manifested only in the relative abundance and not in the richness of the species. The assemblages of fragmented forest exhibited greater variation in species composition and a greater abundance of frugivorous and nectarivorous bats in comparison with the assemblages of continuous forest. The landscape configuration was related to the assemblage- and population-level attributes, contrasting with previous studies where the composition was a key element. At habitat level, tree density and canopy cover determined the abundance of bats. Nectarivorous and frugivorous bats were mostly found in disturbed vegetation landscapes, primarily due to landscape configuration (e.g. edge density). This phenomenon could be a response to the availability of food in primary and intermediate successional stages, which are characterized by an abundance of food value.

Efectos de la estructura del paisaje y de la vegetación en la diversidad de murciélagos filostómidos (Chiroptera: Phyllostomidae) de Oaxaca, México / Effects of landscape and vegetation structure on the diversity of phyllostomid bats (Chiroptera: Phyllostomidae) in Oaxaca, Mexico

The tropical forest fragmentation is known to affect the spatial structure of the landscape and habitat. These alterations can modify the attributes of bat assemblages, however, this phenomenon has been little studied and understood. In this work we evaluated the structure of landscape (i.e. composition and configuration) and vegetation, and its relationship with assemblage- and population-level characteristics of phyllostomid bats in a tropical rainforest of Southeastern Mexico. For this, we previously selected 12 sites located in continuous and fragmented forests, where bats were captured using mist nets during a two years sampling effort (144 nights). Bats relative abundance, species richness (diversity of order 0, 0D), Shannon diversity index (¹D) and Simpson index (²D) were evaluated in all sites, and their relationship with seven measures of landscape structure and seven measures of vegetation structure was described using a Hierarchical Partitioning Analysis. A total of 1 840 individuals of 29 species of phyllostomid bats were captured in this period. Differences in the assemblages were manifested only in the relative abundance and not in the richness of the species. The assemblages of fragmented forest exhibited greater variation in species composition and a greater abundance of frugivorous and nectarivorous bats in comparison with the assemblages of continuous forest. The landscape configuration was related to the assemblage- and population-level attributes, contrasting with previous studies where the composition was a key element. At habitat level, tree density and canopy cover determined the abundance of bats. Nectarivorous and frugivorous bats were mostly found in disturbed vegetation landscapes, primarily due to landscape configuration (e.g. edge density). This phenomenon could be a response to the availability of food in primary and intermediate successional stages, which are characterized by an abun-dance of food value.

La fragmentación de bisques tropicales altera la estructura especial del paisaje y del habitat . Estas alteraciones pueden modificar los atributos de las agregaciones de murciélagos, sin embargo este fenómeno ha sido poco estudiado y comprendido. Se evaluó la estructura del paisaje (i.e. composición y configuración) y vegetación, y sus relaciones con características a nivel de agregación (ensamble) y población de murciélagos filostómidos en una selva tropical del sureste de México. Se encontró que las modificaciones en las agregaciones solo se manifiestan en la abundancia relativa y no en la riqueza de especies. La configuración del paisaje fue un elemento relacionado con los atributos a nivel de ensamble y de población, contrastando con estudios previos donde la composición fue un elemento clave. A nivel de hábitat se encontró que la densidad arbórea y cobertura del dosel determinan la abundancia de murciélagos. Los murciélagos nectarívoros y frugívoros prefieren paisajes con vegetación alterada y están relacionados principalmente con la configuración del paisaje. Este fenómeno podría ser una respuesta a la disponibilidad de alimento en ambientes sucesionales primarios e intermedios, que se caracterizan por una alta proliferación de plantas con potencial alimenticio.

Density, distribution, and activity of the ocelot Leopardus pardalis (Carnivora: Felidae) in Southeast Mexican rainforests.

The ocelot Leopardus pardalis is of particular significance in terrestrial communities due to its ecological role within the group of small-sized felids and as a mesopredator. However, despite the reduction of ocelot habitat in Southeast Mexico, there are still very few ecological studies. This research aimed to contribute with some ecological aspects of the species in this region. For this, 29 camera trap stations were established in a rain forest in Los Chimalapas (an area of 22 km2) during a two years period (March 2011-June, 2013), in Oaxaca state, Southeast Mexico. Data allowed the estimation of the population density, activity pattern, sex ratio, residence time, and spatial distribution. Population density was calculated using Capture-Recapture Models for demographically open populations; besides, circular techniques were used to determine if nocturnal and diurnal activity varied significantly over the seasons, and Multiple Discriminant Analysis was used to determine which of the selected environmental variables best explained ocelot abundance in the region. A total of 103 ocelot records were obtained, with a total sampling effort of 8,529 trap-days. Density of 22-38 individuals/100 km2 was estimated. Ocelot population had a high proportion of transient individuals in the zone (55%), and the sex ratio was statistically equal to 1:1. Ocelot activity was more frequent at night (1:00-6:00h), but it also exhibited diurnal activity throughout the study period. Ocelot spatial distribution was positively affected by the proximity to the village as well as by the amount of prey. The ocelot population here appears to be stable, with a density similar to other regions in Central and South America, which could be attributed to the diversity of prey species and a low degree of disturbance in Los Chimalapas.

Population dynamics of the bat Dermanura tolteca (Chiroptera: Phyllostomidae) in a tropical forest in Mexico

The fruit-eating bat, Dermanura tolteca, has a broad geographic distribution in Mexico and it is a very important seed dispersal of Neotropical plants. Nonetheless, information on the biology of this bat species is scarce, especially with regard to demography. We studied some ecological aspects and population dynamics of D. tolteca from Southeastern Mexican State of Oaxaca. The study was conducted in a perennial tropical forest, over a period of 80 nights, a sampling effort of 73 200 mist-net-hour, from May 2006 to August 2007. A total of 176 specimens were captured, 98 females and 78 males. Population size was estimated in 237 individuals in the study area, with a greater number during rainy season. The population density of this bat, in its range of distribution in Mexico is low compared to other nose-leaf bats. Captures were correlated with monthly precipitation, and this result may be linked to food resources abundance in tropical and subtropical areas. The reproductive pattern was bimodal polyestrous, with birth periods between August-September and April-June. Greater body mass was observed in females than males. The male-female ratio and age-related demographics were similar to other noseleaf bats. The biological characteristics of D. tolteca are typical of nose-leaf bats of the family Phyllostomidae. Rev. Biol. Trop. 58 (4): 1323-1334. Epub 2010 December 01.

El murciélago Dermanura tolteca presenta una amplia distribución geográfica en México y es un importante dispersor de semillas de una variedad de plantas neotropicales. Sin embargo la información biológica sobre este murciélago es escasa, especialmente en aspectos demográficos. El objetivo de este trabajo fue documentar la dinámica poblacional y varios aspectos ecológicos de la especie. El trabajo fue conducido entre mayo 2006 y agosto 2007 en un bosque tropical perennifolio en el estado de Oaxaca, sureste de México, durante 80 noches, con un esfuerzo de muestreo total de 73 200m² de red-hora. Se capturaron 187 individuos, 98 hembras y 78 machos. Se estimó el tamaño poblacional en 237 individuos, con un mayor número en la época lluviosa. Las capturas están correlacionadas con la precipitación mensual y este fenómeno puede estar ligado a la abundancia del recurso alimenticio en zonas tropicales y subtropicales. La proporción de sexos y la estructura de edad son las típicas de varios murciélagos filostómidos. El patrón de reproducción fue del tipo poliestrica bimodal, con periodos de nacimiento entre agosto-septiembre y abril-junio. Las hembras muestran mayor peso corporal que los machos. Es posible que este murciélago presente una baja densidad comparada con la de otros murciélagos filostómidos en todo su rango de distribución en México.

Population dynamics of the bat Dermanura tolteca (Chiroptera: Phyllostomidae) in a tropical forest in Mexico.

The fruit-eating bat, Dermanura tolteca, has a broad geographic distribution in Mexico and it is a very important seed dispersal of Neotropical plants. Nonetheless, information on the biology of this bat species is scarce, especially with regard to demography. We studied some ecological aspects and population dynamics of D. tolteca from Southeastern Mexican State of Oaxaca. The study was conducted in a perennial tropical forest, over a period of 80 nights, a sampling effort of 73 200 mist-net-hour, from May 2006 to August 2007. A total of 176 specimens were captured, 98 females and 78 males. Population size was estimated in 237 individuals in the study area, with a greater number during rainy season. The population density of this bat, in its range of distribution in Mexico is low compared to other nose-leaf bats. Captures were correlated with monthly precipitation, and this result may be linked to food resources abundance in tropical and subtropical areas. The reproductive pattern was bimodal polyestrous, with birth periods between August-September and April-June. Greater body mass was observed in females than males. The male-female ratio and age-related demographics were similar to other nose-leaf bats. The biological characteristics of D. tolteca are typical of nose-leaf bats of the family Phyllostomidae.