Adjustment of honey load by honeybee pollen foragers departing from the hive: the effect of pollen load size

摘要

Honeybee foragers load a small amount of honey into the crop when they leave the hive. This "honey at departure" is used as a material to build pollen loads (glue honey) as well as fuel during flight in pollen foragers. We investigated the relationship between the size of pollen loads that a forager collected and the amount of honey at departure in the Western honeybee, Apis mellifera. Dancing pollen foragers increased honey at departure with the size of collected pollen loads. Analysis of the waggle-run duration revealed that the size of pollen load affected the rate of increase of honey at departure with food source distance in dancers. The increase rate was significantly higher in dancers that had returned to the hive with large pollen loads versus nectar-collecting dancers, but not in those with smaller pollen loads. The higher increase rate may reflect additional fuel carried for the return trip in pollen-foraging specialists that do not use collected nectar as fuel. Although honey carried by departing dance followers also increased significantly with the size of pollen load carried by dancers, the adjustment was different from that of dancers. These results suggest that recruited bees adjust the amount of honey at departure, including glue honey, based on communicated information and modify the amount of honey load subsequently based on their own experience.