On Nest Densities of the Leaf-Cutting Ant Atta cephalotes in Tropical Primary Forest

Abstract

Atta nest densities in six undisturbed primary rain forest ecosystems in the Orinoco-Amazon basin have been estimated. The only species encountered was Atta cephalotes which occurred at a maximal density of 0.045 nests per ha. Three possible explanations for these low densities in contrast to those found in disturbed habitats are discussed. The number of clearings in the forest is proposed to be the limiting factor for colonization of new forest sites by A. cephalotes.