Sleeping Bumblebees Can Survive a Week of Drowning

If you fall into a deep sleep in a full bathtub, you might not expect to wake up — unless you’re a queen bumblebee.

In fact, eastern queen bumblebees can hibernate underwater in frigid temperatures for up to a week. That’s what one ecologist discovered by accident, after receiving a shipment of 300 queen bees for unrelated research.

Sabrina Rondeau took delivery of the eastern bumblebee (Bombus impatiens) queens at Canada’s University of Guelph in 2021. Rondeau was studying how pesticides affect the bees during hibernation by placing them in topsoil-filled tubes, then refrigerating them — a method that mimics their natural dormancy cycle.

But Rondeau opened the fridge one day to a sorry sight: four of the tubes had filled with condensation, completely submerging the fuzzy insects inside.

Freaked out

“I kind of freaked out,” she said. “I was sure the queens were dead.”

Rondeau did her diligence, removing the bees from what she assumed were their tombs. Instead, all four queens stirred, then revived.

“[It was] really surprising,” said colleague Nigel Raine. “These are terrestrial organisms; they’re not really designed to be underwater.”

Don’t tell them that.

Rondeau and Raine quickly shifted gears to test the bees’ submarine resilience. When they further tested 143 bees, 81% of the queens submerged for a week survived.

Scientists still aren’t sure exactly how the bees do this, but it’s a testament to the cornerstone pollinator’s survivability. Queen bumblebees can spend months underground each winter, sleeping through the cold, wet months until they emerge again to feed and nest.

So while one-third of all bumblebee species around the world are in decline, this surprising insect seems to have a few survival tricks we were unaware of.

This widespread story of the bumblebees’ adaptability, which in the last couple of days has appeared in outlets from CNN to New Scientist, prompted media critic Rusty Foster to comment archly in his Today in Tabs newsletter:

“We accidentally drowned some bumblebees but then unexpectedly they lived, so we’re calling that “exciting new research results” and planning to drown a lot more bumblebees. Scientists!”

Sam Anderson

Sam Anderson takes any writing assignments he can talk his way into while intermittently traveling the American West and Mexico in search of margaritas — er, adventure. He parlayed a decade of roving trade work into a life of fair-weather rock climbing and truck dwelling before (to his parents’ evident relief) finding a way to put his BA in English to use. Sam loves animals, sleeping outdoors, campfire refreshments and a good story.