Diversity, ecology, and vulcanism: bird assemblages of the Colima Volcanic Complex, Mexico

Abstract

Deterministic processes are fundamental in structuring the bird assemblages of the Colima Volcanic Complex, an area of high endemism, migration, and taxonomic turnover, but also for its volcanic activity, complex elevational gradient, and vegetation types. Herein we describe the bird assemblages of Colima Volcanic Complex and the ecological and biogeographical mechanisms that structure the species composition, based on incidence data and environmental variables. The results show that volcanic risk, elevational gradient, and cardinal orientation, are the explicative variables of the species richness patterns. A total of 397 species were recorded; 248 (62.5%) of which are residents, 149 (37.5%) are migratory, and 89 (22.4%) are in some category of endemism. There is a high dissimilarity (βSOR = 0.907) caused by a high taxonomic turnover (βSIM = 0.749). The most represented biogeographical affinity is the Mesoamerican domain with 41-47% of the resident species. We conclude that ecological and biogeographical processes structure the regional avifauna, providing a first approach to the understanding of volcanic activity as an active mechanism in the regional biological dynamics.