The role of vegetation structure and abiotic factors affecting the temporal dynamics of ant foraging

Abstract

The study of foraging dynamics is essential to understanding the way organisms arrange themselves to reduce the effects of competition in the most diverse natural systems. The analysis of temporal foraging patterns is an important tool for understanding how ant communities respond to different environmental conditions. Thus, to verify how complexity of the vegetation and abiotic factors can influence ground-dwelling ants communities, we evaluated the foraging temporal patterns in three types of landscapes (Grassland, Arboreal Caatinga, Shrub Caatinga) in an area of dry seasonal rainforest. These environments were characterized by abundance of plant life forms. The ants were collected by pitfall trap, arranged in six rows each with five traps. The pitfalls were inspected every hour from 7:00 am to 6:00 pm, and temperature and humidity data were taken at the same time. The foraging structure of ant communities presented a nested pattern between the phytophysiognomies, but with variation in the observed metric values. For less complex environments, foraging activity was restricted to preferential times, demonstrating a temporal niche partition. Despite more complex environments have a greater richness of species foraging throughout the day, we found greater diversity in environment with intermediate complexity. Temperature influences the richness of foraging ants throughout the day, but we found no effect on diversity. Our results indicate that, although temperature may influence the temporal dynamics of ground-dwelling ant communities, changes in the structural complexity of the environment affect the foraging activity among species, influencing ant-mediated ecological processes.