Effect of forest disturbance on ant (Hymenoptera: Formicidae) diversity in a Mexican tropical dry forest canopy

Abstract

Abstract1. Ants are the dominant insects in tropical forest canopies. The α and β diversities of ants change in response to forest disturbance. Understanding the response of ants to forest disturbance will help to guide ant conservation and forest management plans, especially in endangered ecosystems such as the tropical dry forest. 2. We analysed ant α and β diversities in 15 fragments (5 mature, 5 disturbed, and 5 secondary) of a tropical dry forest in central Mexico. We identified and measured all of the trees in two transects (10 × 50 m) established within each fragment. Pit‐fall traps were used to sample ants in all of the trees. 3. We identified 52 ant species (from a total of 11,524 individuals). The mature forest presented the greatest quantity of exclusive species and the highest α diversity. Ant composition differed among the mature forest but not between disturbed and secondary forest, and was related to tree size and richness. The β diversity was lower in the disturbed forest, reflecting the cost of biotic homogenization (15%). Among the β diversity components in all three forest types, this diversity was mainly influenced by turnover, while nestedness diminished in the disturbed forest. 4. In the tropical dry forest studied, anthropogenic disturbance homogenises the ant community, probably because the availability of resources is also homogenised, decreasing the α diversities of the canopy ants. Our results show the importance of the conservation of mature forests in terms of maintaining the diversity of canopy ants.