When you think of an aquatic animal, a bee is probably not what springs to mind. Yet new research indicates that certain bumblebees can survive completely submerged for at least a week, suggesting that they are far more resilient than anyone thought.
This discovery happened completely by accident in the lab of Dr. Sabrina Rondeau, then an ecologist at the University of Guelph in Canada. In 2021, Rondeau was studying the effects of pesticides on hibernating queen bees (specifically, common eastern bumblebees) by storing them in 300 soil-filled tubes in a refrigerator in an attempt to replicate the conditions in which they hibernate. When she opened the refrigerator several days later, she was dismayed to find that condensation in the fridge had produced enough water to completely submerge four of the insects.
Yet rather than mourning the loss of her research subjects, Rondeau made a fascinating discovery: all four of those queens had survived and soon started moving when returned to a dry environment. To further investigate their miraculous survival, Rondeau then conducted an experiment in which she exposed 143 hibernating common eastern bumblebee queens to various levels of water for either eight hours, one day, or one week. The control group was kept dry, another group floated on the water’s surface, and the last group was completely submerged.
Twenty-one bees were submerged for an entire week, and 17 of them (81%) survived the experience and resumed their normal appearance and behavior once returned to a dry vial. The bees that were kept dry for the full week had a survival rate of 88%, only slightly higher than the fully underwater queens. All of the groups appeared comparably healthy when checked eight weeks later. Interestingly, the heaviest bees appeared to have the best chance of survival overall.
Survival miracle or basic bee anatomy?
- *Researchers remain baffled at how the bees, which are terrestrial creatures, were able to withstand being underwater for days without drowning. However, the mechanics of bee hibernation offer some clues. Queen bees spend around eight months underground between autumn and spring, with their metabolism greatly slowed and little oxygen intake, before emerging to start a new colony.
- *The queen bees’ ability to withstand submersion seems like a huge advantage for their survival while underground. It means they have a good chance to escape unscathed when subjected to flooding, which appears to be becoming more frequent due to climate change.
- *The astounding results of Rondeau’s research leave many questions still unanswered. Beside the basic quandary of how their anatomy prevents them from drowning, scientists are also wondering whether the queens suffer any lasting negative effects from submersion. And presumably, the bees can’t survive underwater indefinitely, even in their hibernating state. There is also the question of how common this ability is among species besides the common eastern bumblebee.
