Hygienic behavior in Brazilian stingless bees (Apidae, Meliponini)

Abstract

Social insects have many defense mechanisms against pests and pathogens. One of these is hygienic behavior, which has been studied in detail in the honey bee, Apis mellifera. Hygienic honey bee workers remove dead and diseased larvae and pupae from capped brood cells, thereby reducing the chance that the disease will spread within the colony. Stingless bees, Meliponinae, are common in Brazil, with c. 250 native species, and are increasingly being used for honey production and crop pollination. Like honey bees, stingless bees rear brood in sealed cells. However, there has been little research carried out on hygienic behavior in stingless bees. The project will investigate hygienic behavior in 3 species of stingless bees native to Brazil: Melipona scutellaris, Scaptotrigona depilis, Tetragonisca angustula. The main aim, Experiment 1, will be to characterize levels of hygienic behaviour that occur naturally in these 3 Brazilian stingless bee species against brood killed by freezing, which simulates the effect of a pathogen that kills brood. Experiment 2 will determine whether hygienic behavior is also effective against an important pest of stingless bees, phorid flies (Diptera, Phoridae), which can feed in a brood cell on the food placed there by the bees for the larva. Experiment 3 will characterize the behaviors carried out by worker bees engaged in hygienic behavior. The project will be carried out by Professor Francis Ratnieks (University of Sussex, England) in collaboration with Dr. Denise de Araujo Alves and Professor José Maurício Simões Bento of the Department of Entomology and Acarology, ESALQ, Piracicabam São Paulo State. The project will use existing hives and other facilities in the Laboratories of Beneficial Insects (Dr. Alves) and Chemical Ecology & Insect Behaviors (Prof. Simões Bento) at ESALQ. The results will be an important contribution to the biology of stingless bees and will also be of value in beekeeping and crop pollination with stingless bees in Brazil. The results will be written up for publication in an international scientific journal. (AU)