If you’ve ever seen a dead bee that looks like it’s partially burst, it’s likely that it died a more NSFW death than you imagined — it seems out that when drones die in intense heat, their final move is to ejaculate out a portion of their own abdomen. Dr. Alison McAfee, a postdoctoral fellow at UBC’s Michael Smith Laboratories and an expert in bee health, stated in a statement that when drones die from shock, they spontaneously ejaculate. “They have a large endophallus that protrudes from their bodies and is roughly the size of their own abdomen. It’s a bit of a stretch.”
McAfee and her colleagues sought to chill hives to prevent bees from “explosively ejaculating to death” in a research analyzing bee die-offs during high heatwaves in British Columbia. After one beekeeper approached McAfee with images of dead drones during a 2021 heatwave, he discovered that others in the vicinity had seen similar significant die-offs, particularly of their tiny beginning colonies known as “nucs.” Some beekeepers reported losing up to half of their nucs.
McAfee had been focusing on queen bees as a method of monitoring the environment, but he recognized that drone deaths may be just as essential. “We know that half of drones will die of heat stress after six hours at 42 degrees,” McAfee stated. “At two or three hours, the more delicate ones start to die. That’s not a temperature they should be exposed to on a regular basis, yet drones were being stressed to the point of death.”
In addition to reducing the resources available for bees to build new hives, fewer drones mean less genetic variation. This might lead to a decrease in disease resistance and other issues. Only 40 percent of queen bees successfully mated during the heatwave investigated, compared to 75 to 80 percent in better conditions. McAfee attempted a various techniques of cooling the hives while monitoring the temperature throughout the heatwave to avoid these issues.
One solution was to provide the bees with a sort of cooling station in the form of a sugar syrup feeder. “Bees would naturally seek out water to bring back to the hive and cool down by fanning it with their wings, which produces evaporative cooling in the same way that we do when we sweat,” McAfee stated. “Putting syrup nearby should allow them to accomplish the same thing, and the sugar in it will encourage them to eat it quicker.”
The alternative solution, while less attractive, was more effective: covering the hives with styrofoam lids. Cooling stations kept hives 1.1°C (1.98°F) lower than controls, whereas styrofoam covers kept hives 3.5°C (6.3°F) cooler. Furthermore, the styrofoam insulation maintained temperatures consistent, making the hive warmer at night and cooler during the day, so it could be used to protect bees from the cold in the winter and from ejaculating themselves to death in the summer.
