As it turns out, the male honeybee, or drone, suffers an extremely painful death during heat waves. We may think they die of heat stroke, but in fact they ejaculate until they die. Scientists are disturbed by this discovery.
The male bees get overheated, convulse, and explosively ejaculate themselves to death. The phallus that bursts from their lifeless bodies is the size of their abdomen.
Alison McAfee is a biochemist who specializes in honeybee fertility, and a post-doctoral fellow at University of British Columbia (UBC) and North Carolina State University. She stated that it is unknown why drones ejaculate post-mortem, but experts at UBC believe there is a remedy for the problem.
A possible solution is to cool the hives during extreme heat by using something like a polystyrene cover. A 2-inch polystyrene cover cools the hive by 4 degrees, which should hopefully keep the insects alive.
Dr. McAfee conducted research along with Armstrong-based beekeeper Emily Huxter, who reached out to McAfee initially about the project, and McAfee found the drone deaths very concerning. During the research, Huxter stayed on the ground and McAfee performed analysis remotely.
Drones always die after they mate, but the ejection of a phallus from their abdomen is unusual. A drone has only one known purpose: to mate with a virgin queen when he is sexually mature. They fly to the congregation area where drones from other hives go to find a virgin queen to chase in mid-air. They do not contribute in other ways to the hive. They are fed by worker bees, but when autumn comes, if they haven’t mated and died, they are kicked out of the hive to die alone.
Drones contain an entire phallus inside them. Their abdominal muscles contract very strongly when they mate. This same thing happens when they die for stress-induced reasons that we don’t understand, and this can cause the endo-phallus to appear outside their body, as explained by Dr. McAfee. She also said that the protrusion was a partial version, only about half of the structure.
This unrelated 9:05-minute video by insectsappeal is very educational about drone mating, if a little unusual:
McAfee is concerned that the film of the 2-inch polystyrene cover won’t cool the hive center, and this is where the queen lives. She wants to give drones syrup and polystyrene to carry into the hot dense core.
The polystyrene alone may be enough to prevent some colonies from dying but is only likely to work with smaller hives that are easier to cool.
According to scientists, about half of male bees will die after six hours at 42°C (107.6°F). This happened in British Columbia when it got that hot last summer, putting a dent in the local bee population. This could happen again in 2022.
Why it happens is a total mystery, says McAfee. More research must be done, and she intends to do it with Huxter. Eventually, she will check the temperature in different parts of the colony, not just the area right under the lid.
McAfee has studied the effects of heat on the fertility and survival of bees for years. She thought it was more of an issue for bees that get too hot when they’re being shipped from one province or country to another, in an unnatural environment. This is now making her think about other insects, too.
Bees do team work to keep themselves alive, but solitary insects don’t have that protection. If the heat is affecting honeybees, McAfee thinks it’s very likely that native species and wild insects are affected as well. Which makes this a super important area for ongoing research, she says.
The experiment has not been peer-reviewed, but several beekeeping experts at UBC back its findings.
If you want to see images of the poor dead and dismembered male drone bees, you can click here to view them.