Artificial Breeding of Native Bumblebees Bombus atratus y Bombus bellicosus (Hymenoptera, Apidae)

Abstract

Bumblebees (Bombus) are excellent pollinators that contribute to the maintenance of many ecosystems and commercial crop production. Commercial rearing of bumblebees has been performed for 30 years with some Eurasian and Northamerican species. Uruguay has two native bumblebees: Bombus atratus y B. bellicosus, whose artificial rearing is considered difficult. During the spring and summer of 2009-2010 and 2010-2011 breeding experiments were performed with both species of bumblebees. Experiences started with mated queens recently emerged from hibernation captured during spring. Queens were placed in wooden boxes of 5x10x10 cm with a pollen ball of 1.5-2 cm diameter and sugar syrup 50%, and were kept in an oven at 28 ºC. The 2009-2010 experience started with 42 queens (40 B. atratus and 2 B. bellicosus) and the 2010-2011 experience with 89 queens (82 B. atratus and 7 B. bellicosus). The 21.5 and 30.3% of the queens in the first and second experience respectively, had at least one worker. The greatest loss of queens was found in the period from the introduction of the queen in the box until the onset of oviposition (64.3 and 53.9% for the first and second experience, respectively). Results obtained in these small scale experiences are in the range of those reported under similar conditions for other bumblebee species.