| [altitudinal distribution, richness and composition of bird assemblages in a mountainous region in southern nayarit, mexico]. | elevation gradient studies have strengthened the evaluation of changes in richness and composition of bird assemblages. they also provide information on environmental variables that determine bird distribution, and the variables that define their population structure. our aim was to describe their variation through an elevational cline in southern nayarit, mexico. to analyze the behavior of richness across the gradient, we gathered information through point counts in nine elevational intervals ( ... | 2016 | 29465917 |