Postdiapause mating in bumblebee queens (Bombus terrestris): a novel strategy for conservation and laboratory breeding

Abstract

In bumblebees, successful colony establishment typically requires mating before diapause, as unmated queens were previously thought to have limited reproductive potential. However, the possibility of postdiapause mating has remained largely unexplored. This study investigated the reproductive success of Bombus terrestris queens by reversing the typical sequence of mating and diapause under laboratory conditions. Gynes underwent diapause for 4 or 7 months before mating with unrelated males. The results revealed high survival rates during diapause, with no significant differences between the two diapause durations. Postdiapause mating success was also high, with 82.6% of queens in the 4-month group and 77.7% in the 7-month group successfully mating. The length of diapause appeared to slightly affect the ability of nests to produce new gynes, but the difference was not statistically significant. These findings challenge the assumption that unmated gynes are inevitably constrained in their reproductive potential. If confirmed in other species, this strategy could provide a valuable tool for conservation breeding programs.