Geographic and ecological analysis of the Bearded Wood Partridge Dendrortyx barbatus: some insights on its conservation status

Delimiting 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 decision-making process for conservation. One example is the BeardedWood 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 BeardedWood 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.