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SummaryDelimiting the distribution of a species is a complex task because many determining factors are difficult to assess in the field. This is important because distribution is a key factor in the decisionmaking process for conservation. One example is the Bearded Wood Partridge Dendrortyx barbatus, a species endemic to the temperate forests of the Sierra Madre Oriental (SMO) mountain range in Mexico. Lack of knowledge of its distribution has generated confusion over the assignment of the correct risk category. With the aim of predicting the distribution area of the Bearded Wood Partridge and contributing to strategies for its conservation, we updated and extended the knowledge of its distribution by modelling its ecological niche using GARP and MaxEnt algorithms. We also analysed its environmental distribution using principal components analysis, and contrasted the two most important environmental variables with the species's distribution based on vegetation type. We found that the area potentially occupied by this species covers 17,956 km 2 according to GARP and 12,974 km 2 according to MaxEnt. We suggest that there is a biogeographic barrier which limits the distribution of this species in the southern part of its range. The abiotic variables that best explain its distribution are average annual precipitation and elevation, both of which coincide well with the distribution of cloud forest. A redefinition of the current range as recognised by IUCN is proposed along with the need to change its national risk category. ResumenDelimitar el área de distribución de una especie es una tarea compleja debido a que los factores que la determinan son difíciles de evaluar en campo; sin embargo, esto es importante porque el área de distribución de una especie es un factor determinante para la toma de decisiones en conservación. Este es el caso del Chivizcoyo Dendrortyx barbatus, una especie endémica a los bosques templados de la Sierra Madre Oriental (SMO) en México, cuya falta de conocimiento de su área de distribución ha generado confusión con respecto a su categoría de riesgo. Con el objetivo de predecir el área de distribución y contribuir con estrategias para su conservación, hemos actualizado y ampliado el conocimiento en torno a su distribución mediante el uso de modelado de nicho ecológico utilizando los algoritmos GARP y MaxEnt. También analizamos la distribución ambiental mediante un análisis de componentes principales y contrastamos las dos variables más importantes con los tipos de vegetación que frecuenta la especie. Los resultados obtenidos fueron que el área de distribución potencial de la especie de acuerdo con GARP fue de 17,956 km 2 y 12,974 km 2 con base en MaxEnt. Sugerimos la existencia de una barrera biogeográfica que delimita su área al sur de su distribución. La precipitación media anual y la altitud son las dos variables que explicaron mejor los patrones de distribución de la especie, cuyos valores coincidieron mayormente con el bosque mesófilo de montaña. Proponemos una redefinición del área de ...

Tropical forests are home to a rich biodiversity, and protected natural areas (PNA) represent one of the approaches adopted for conserving this biodiversity. However, PNAs are under constant threat of becoming too isolated in a landscape matrix frequently hostile to most of the species they harbor. A new system of conservation has recently been proposed in the form of areas under private protection (privately protected areas or PPAs) that complement the existing PNAs in their task of conservation. The objective of this study was to document the richness of mammal species that inhabit a 100 ha fragment of rain forest and pasture decreed as a PPA in southeastern Veracruz, Mexico, and to compare it to two nearby PPAs and one PNA of contrasting conservation values. Mammals were monitored in the three climatic seasons of the year through direct observation, track identification, and the use of Tomahawk, Sherman, and camera traps, as well as mist nets. We recorded 32 mammal species-including seven threatened species-belonging to 28 genera and 15 families. These results are important considering that 29 and 14 species have been reported for two other PPAs in the region that are 10 times larger. However, large mammals of the Orders Carnivora, Artyodactyla, and Perissodactyla were absent and are probably locally extinct. We propose that, under specific favorable conditions, forested PPAs can make an important contribution to strategies designed for biodiversity conservation in tropical ecosystems, by helping to conserve endangered species of both medium-and smallsized mammals.