FORAGING STRATEGIES OF STINGLESS BEES (APIDAE, MELIPONINAE): THE RELATION BETWEEN PRECISION OF RECRUITMENT, COMPETITION AND COMMUNICATION.

Interspecific differences in foraging strategies of five species of stingless bees (Nannotrigona testaceicornis, Trigona corvina, T. fulviventris, T. nigra, Scaptotrigona pectoralis) were studied in Pozo Azul, Costa Rica. In several experiments, recruitment rate and competitive behavior were observed. One to four scouts of a feral nest were trained to feed from an artificial food source at 100 meters from the nest, after which two additional sources were opened at 10 and 20 meters from the first source and scouts were free to recruit. The rate of recruitment and initial time to start recruitment showed high variance between the species. T. nigra did not show any significant recruitment whereas S. pectoralis recruited significantly more foragers than the other species during the first hour. N. testaceicornis and S. pectoralis started recruitment significantly earlier than the other species. By means of direct observation on aggressive behavior and source monopolization of two species at the same source, the following dominance order was found: T. corvina>T. fulviventris>S. pectoralis>T. nigra / N. testaceicornis; the species with the most precise recruitment being dominant over the species with no or less precise recruitment.