Niche differentiation and its relationship with food abundance and vegetation complexity in four frugivorous bat species in southern Mexico

Species can co-exist within a community when their use of limiting resources is differentiated. To test whether differentiation facilitates coexistence, we quantified differences and overlap in habitat use, fruit consumption, morphological characteristics, and the relationship with vegetation structure for two pairs of ecologically similar frugivorous bat species, Carollia sowelli and C. perspicillata, and Artibeus jamaicensis and A. lituratus. In Carollia sowelli and C. perspicillata, differences in body mass and wing aspect ratio were not reflected in differences in fruit or habitat use (diet overlap, 96 percent; habitat overlap, 98 percent). However, the capture rate of Carollia sowelli positively correlated with canopy openness, and that of C. perspicillata positively correlated with tree height. Body mass and wing characteristics of Artibeus species suggested a greater maneuverability for A. jamaicensis. Also, more A. jamaicensis individuals were captured feeding on Ficus spp., while Artibeus lituratus preferred fruits of the early successional tree Cecropia. However, both habitat overlap and diet overlap were higher than by chance (diet overlap, 75 percent; habitat overlap, 92 percent). The co-existence of the four bat species in the study area may be facilitated by the abundance of the food resources forming part of the diets of both Carollia species, by the morphological differences between the Artibeus species, which allow the differentiation of foraging behavior in relation to fruit consumption, and by the structural characteristics of the vegetation