I have two hobbies: beekeeping and building/flying multirotors or drones. There is rarely any overlap between the two but recently I have noticed a spate of YouTube videos with titles such as:
- Bees Attack Quadcopter Blades
- Angry Swarm of Bees Attack Drone also see Angry Swarm of Bees Attack Drone
- Quadcopter Attacked by Swarm of Bees
- Quadcopter/Drone attacked by Swarm of Bees
- Swarm of Bees Attack Drone. Bees vs. Drone
- Ar Drone Bee Attack!!
- FPV Drone Attacked by Drones Swarm Africanized Killer Bees Attack Guarding Queen
Some of these videos are picked up by the media and further sensationalized. Too bad they all get the story so wrong. These bees, drones actually, are not angry. They are simply horny and they think they found a virgin queen worth dying for.
For those readers new to honey bees, I offer this quick summary of honey bee biology. Honey bees have three castes or forms: sterile females or workers, males or drones, and typically a single reproductive female or queen. A queen's job is to lay eggs. She can lay up to 1500 eggs a day for several years. But first, she needs to copulate with about 12 (plus or minus 7) drones because she will never mate again once she starts laying eggs. Drones are flying penises. They carry genetic material. That's about all they are good for. They don't even have stingers like the girls do. Most drones will never mate with a queen but when they do, they do it in the air, the drone has his gonads ripped out of his body, and he falls to his death. Satisfied, I hope. The workers handle every other task: feed the queen and growing larva, put away honey, build out wax comb, fill cracks with bee glue, take out the dead, guard the entrance, warm or cool the inside of the hive, and forage for food.
What all of these videos show are drone congregation areas or DCAs. These are areas where drones from different colonies gather in hope of mating with a queen. A DCA is typically 10-40 meters above ground with a diameter of 30-200 meters. The utility of a DCA is that it provides an efficient way for a queen to acquire genetic material from outside of her own colony. Inbreeding is bad for any species.
DCAs have been known to persist in one geographic location for 12 years. This is curious because drones do not survive the winter as workers do (the girls kick their brothers out of the hive each Fall) so there must be something intrinsic in the area itself to attract drones from multiple colonies to the same place year after year. Yet another honey bee mystery waiting to be solved.
Drone congregation areas are not rare but their discovery is rare. They are normally discovered in urban areas by observing a number of dead drones on the concrete or asphalt. Balloons and kites with suspended nets and pheromone lures have been used in the past to study DCA but perhaps multirotors could offer a better research platform, eh?
How can I be so sure that these videos are of drone congregation areas?
- If you step through frames, you will see that these bees have rounded bottoms - that is the stingless abdomen of a drone.
- Workers have no reason to congregate above tree level because there is no food there. They may fly above tree level to reach a nectar source 3 miles distant but they do not tarry nor do they travel in packs.
- I know, I know, that's not what happens in the movie "Deadly Bees" but honey bees away from their colony are not aggressive. They will defend their colony and themselves but they do not attack unprovoked. Honey bees are vegetarians, for Pete's sake.
- The buzz of a multicopter may attract the horny drones in a congregation area. But I have flown my multirotor within a few feet of three busy hives - seeking to solicit a response - but the worker bees showed no interest or aggressive behavior at all.
For more information:
- Landscape Analysis of Drone Congregation Areas of the Honey Bee, Apis mellifera
- Of course of you really want to see bees attack a drone and a news crew, there is none better than this report from CNN's Jeanne Moos.