Foraging Behavior and Mortality of Ectatomma brunneum (Hymenoptera, Formicidae) in Simultaneous Exposure to Ant Baits and Conventional Diet in Laboratory by Viviane Cristina Tofolo 1,2 , Edilberto Giannotti 1,3 & Marcos Aparecido Pizano 4 ABSTRACT he objective of this work was to identify whether the presence of leaf- cutting ant baits in the foraging arena of the ant Ectatomma brunneum (Smith) afects its foraging behavior or causes mortality in laboratory. A multiple choice test was used, composed of ant baits with three diferent active ingredients (sulluramid, ipronil and chlorpyrifos) and the usual food based on proteins (Tenebrio mollitor (Linnaeus)) and carbohydrates. Using a camcorder, the observations revealed that the workers of E. brunneum stopped collecting conventional non-toxic food in order to collect toxic bait, hence causing mor- tality by ingestion and by contact with the active ingredients used. Although they visited the sources containing T. mollitor more oten, the few visits to the sources containing ant baits were enough to cause mortality of workers (14.44% with sulluramid and 20% with chlorpyrifos and ipronil). his work showed that the brands of ant baits used, which should be selective only to leaf-cutting ants, were attractive also to this species of non-target ant. Keywords: food choice, ants, sulluramid, ipronil, chlorpyrifos. INTRODUCTION he foraging behavior of many animals may involve complex strategies that help locate resources in the environment. In ants, it is a collective process consisting of both individual and group activities (Traniello 1989). Besides 1 Universidade Estadual Paulista (UNESP) Júlio de Mesquita Filho. Instituto de Biociências, Departamento de Zoologia. Avenida 24-A, 1515, Bairro Bela Vista, Rio Claro/SP, Brazil. CEP: 13506-900 - Phone: 0 55 19 3526-4285 - Fax 0 55 19 3526-4300. 2 E-mail: vivitofolo@yahoo.com.br (student grant by CNPq — Brazil) 3 E-mail: edilgian@rc.unesp.br 4 Universidade Estadual Paulista (UNESP) Júlio de Mesquita Filho. Instituto de Biociências, Departamento de Ecologia. Avenida 24-A, 1515, Bairro Bela Vista, Rio Claro/SP, Brazil. CEP: 13506- 900 - Phone: 0 55 19 3526-4225 - Fax 0 55 19 3526-4226. E-mail: mapizano@rc.unesp.br 599