Copulation Environment Favorable for colony development of the European Bumblebee, Bombus terrersis

We investigated mating conditions about care temperature of queen before mating, mating period, and number of queen per mating cage to improve mating rate of Bombus terrestris. Among $19^{\circ}C$, $22^{\circ}C$ and $25^{\circ}C$, care temperatures of queen before mating, queen cared at $19^{\circ}C$ was more effective than those at $22^{\circ}C$ and $25^{\circ}C$ in death rate during care and mating periods, and colony development In case of mating period, oviposition rate and preoviposition periods at queen mated during 3 days were 89.3% and 11.4 days, respectively, which was higher and earlier than those of queen mated during 5 days and 7 days. The rate of worker emergence, colony foundation and progeny-queen production at 3 days-mated queen were also 2.0-11.6% higher than those at queen mated during 5 days and 7 days. In number of queen per mating cage, the rate of worker emergence, colony foundation and progeny-queen production queen mated at mating cage with 10 queens and 30 males were 41.5%, 25.9% and 23.2%, respectively. These values correspond to 1.5-6.8 folds those queen mated at cage with 20 queens and 30 queens. Therefore, we supposed that care temperature favorable for B. terrestris queen was $19^{\circ}C$ and the period need to mating was 3 days, and the number of queen per mating cage ($55{\times}45{\times}65\;cm$) was 10.