Bumblebees Huddle in Packs When Danger's Near

Bumblebees tend to huddle in packs when they sense that danger is near, according to new research from Queen Mary University of London.

Bumblebees are sophisticated enough to distinguish between safe and dangerous environments, and so are attracted to flowers popular with other bees safely feeding. For their research, scientists had to train bumblebees to be able to sense the difference between safe and unsafe.

When bees landed on a flower associated with danger, foam pincers would trap the bee and prevent it from foraging. This simulates an attack by a crab spider, a predator that lurks on flowers to catch hungry pollinators, and can hide by changing its color.

In safe environments, bumblebees subsequently chose to feed from flowers at random, but in dangerous environments, the bees specifically flew to flowers that were occupied by other bees.

"It's similar to walking through a bad neighborhood -- you're more likely to choose a busier route, where there are lots of other people around than a deserted street, to get to your destination, since your chances of being attacked are probably lower," co-author and PhD student Erika Dawson said.

Chameleon-like predators such as the aforementioned crab spider can be hard to detect. Authors of this study - published in the journal Proceedings of the Royal Society B - suggest that bumblebees exchange information with one another to help them avoid dangerous situations that would lead to an encounter with such a predator.

"These results show a remarkable flexibility in pollinators' strategic foraging decisions. Bees normally spread themselves out among flowers to minimize competition, but when danger lurks they dine together to seek safety in numbers," commented co-author Professor Lars Chittka from Queen Mary's School of Biological and Chemical Sciences.

Bees do have other foes besides the obvious predators. Bees also battle pesticides, parasitic mites, frequently cut lawns and the harsh winter season, according to New Castle News report.