Honey bees warn nest mates of danger

Honey bees warn nest mates about dangers they encounter, with a signal that is like a `stop` sign for others foraging for food at "dangerous" locations.

Last Updated: Feb 13, 2010, 13:24 PM IST

Washington: Honey bees warn nest mates about the dangers they encounter, with a special signal that is like a `stop` sign for others foraging for food at "dangerous" locations, research says.
The discovery resulted from a series of experiments on honey bees foraging for food that were attacked by competitors from nearby colonies fighting for food.

The bees under attack produced a specific signal to stop nest mates which recruited others for "dangerous" locations.

Honey bees use a waggle dance to communicate the location of food and other resources. Attacked bees directed "stop" signals as nest mates waggle, dancing for the dangerous location.

James Nieh, associate biology professor at University of California-San Diego (UCSD), said this peculiar signal was known previously by scientists to reduce waggle dancing and recruitment to food, but until now no one had firmly established a "clear natural trigger" for that behaviour.

The stop sign is a brief vibrating signal lasting a 10th of a second with the bee vibrating at about 380 times per second.

"It is frequently delivered by a sender butting her head into a recipient, although the sender may also climb on top of the receiver," Nieh said.

Bee researchers originally called it a "begging call", because they believed the signalling bee made it to obtain a food sample from the receiver.

But Nieh discovered in his experiments that one trigger for this signal, which caused the waggle dancers to stop and leave the nest, was attacks from bee competitors and simulated predators.

The more dangerous the predator or competitor, he found, the more the stop signals bees produced to prevent other bees from moving to that location. "This signal is directed at bees who are moving towards the dangerous food location," explained Nieh, according to a UCSD release.

The findings are slated for publication in the February issue of Current Biology.