Nice
video! I know that honeybees can communicate with a complex system of pheromones
Honey bee pheromones
The alarm pheromone will alert the rest of the hive that there is trouble, and it is not much fun to be around a hive when the alarm is sent out.
Although it seems that there is a lot less known about bumblebees but I would suspect that it is a similar thing.
from
bumblebee.org "The method of communication is a pheromone (a chemical substance secreted by one animal which influences the behaviour of other animals), however it seems only to encourage other workers to go out to forage; there does not seem to be any other information conveyed by the pheromone. The pheromone contains eucalyptol, farnesol and ocimene, and has been produced artificially. The release of this compound, for short periods at regular intervals, increased foraging traffic 3 fold. This could be used commercially in greenhouses to induce workers in nest newly introduces to the
greenhouse to go out and pollinate the crop by gathering pollen. This is especially useful in crops which produce no nectar such as tomatoes. "