May 20 (UPI) -- With the help of radar technology, scientists are gaining new insights into the sexual lives of honeybee drones.
According to a new study, published Thursday in the journal iScience, bees gather in certain aerial locations where they attempt to intercept and mate with queen bees.
Previously, scientists have observed thousands of male honeybees gathering at "drone congregation areas."
But the phenomena is typically triggered by the deployment of pheromone lures, raising questions about whether the behavior is entirely natural.
For the new study, researchers attempted to spy on the sexual behaviors of honeybee drones using radar imaging. Their findings showed male bees move to and from a few different mating sites.
Scientists were able to track the flight paths of honeybee drones after attaching tiny transponders to the backs of several male bees. When a transponder receives a radar signal, it absorbs the radio waves and reemits a radar signal at a higher frequency.
These returned signals are picked up by a radar antenna, revealing the location and movements of the bees.
Researchers used several different antennas to triangulate the precise positioning of the tagged bees, plotting their movements in relation to landmarks mapped using GPS.
The data showed drones alternate between straight-line flight paths and long, looping flight patterns. Followup analysis showed the bees followed looped flight paths in four distinct locations. These congregation areas remained stable over a period of two years.
Researchers likened the behavior to the mating patterns of deer and mice, both of which gather to mate in areas known as "leks."
"We show that drones frequently visited more than one congregation area on a single flight," lead study author Joe Woodgate said in a news release.
"This is the first evidence for males of any species routinely moving between lek-like congregations and may represent a new form of lek-like mating system in honeybees," said Woodgate, a postdoctoral researcher at Queen Mary University.
Scientists found the flight patterns within the leks is similar to those practiced by swarming mosquitoes and midge flies.
As bees arc away from the center of the lek, they begin to accelerate back toward the center, creating an apparent force that helps stabilize the shape of the swarm.
"Our findings suggest drones locate congregation areas as early as their second ever flight, without apparent extensive search," said study co-author Lars Chittka.
"This implies that they must be able to get the information required to guide them to a congregation from observing the landscape close to their hive. In the future, we will look at how they accomplish this feat," said Chittka, a professor of sensory and behavioral ecology at Queen Mary.