Huge bumblebee and flower

A big big bumblebee pollinates a flower. The bumblebee is so big that it barely fits on the flower. Marvelous. But he flies dozens of times to this flower after making a couple of circles around. It's probably some sort of defensive tactic. The bumblebee is afraid to stay on the flower for a long time. Therefore, after collecting some pollen, the bumblebee flies off a couple of feet and then returns to the flower again.