Several ant species are reported to be important predators of insect pests (Way and Khoo, 1992; Veeresh et al.. 1995). In East Africa, ants were found to be important natural enemies of Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) (Van den Berg and Cock, 1993a, b), one of the most serious pests in the Old World (Reed and Pawar, 1982).