Underwater Hibernation of Queen Bees Lasts Multiple Days, Avoiding Drowning

Underwater Resilience: Queen Bumblebees Survive Immersion for Days

Queen bumblebees have astonishingly demonstrated the ability to survive underwater for extended periods. This capability was discovered incidentally by researcher Sabrina Rondeau while studying hibernating bees for her doctoral studies. The queens survived being submerged in water due to condensation in stored soil-filled tubes, mimicking their natural underground winter burrows.

"I was terrified; it was unexpected," said Rondeau, who found only a small number of bees affected. She was intrigued by their survival and searched for answers, finding no one with relevant information.

To understand the extent of the Queens' underwater endurance, Rondeau and her team carried out experiments on Bombus impatiens queen bees, one of North America's most widespread species. Bumblebee queens were exposed to flooding conditions in carefully controlled tests, remaining submerged for eight hours, 24 hours, or an entire week.

Afterward, the bees were dried and monitored for eight weeks. Strikingly, 81 percent of the queens submerged for a week were alive after two months, nearly mirroring the survival rate of those never immersed. Why would bees evolve such a remarkable skill remains a significant question.

It seems that queens can withstand long periods underwater due to their remarkable lifestyle and an adaptive metabolic response. After mating during late summer or fall, they enter a winter hibernation underground, reducing their metabolic rate to minimal levels. Such hibernation previously only involved burrowing underground. Recent findings suggest that this survival secret may extend to underwater hibernation in response to flooding or other environmental changes.

The team emphasizes that more research is needed to better understand the health effects of immersion on queens and investigate whether this ability is common across different species. However, this discovery offers a lifeline for bumblebee populations faced with increasing flooding events due to climate change.

Climate change is causing more frequent and severe flooding, particularly in urban areas. At the same time, pollinators such as bees are under unparalleled threat from habitat loss, pesticide exposure, and changing weather patterns. The common eastern bumblebee is one of the more resilient species, showing fewer signs of decline. This newfound adaptation to flooding may be a factor in their resilience, offering hope for their survival in changing environments.

This research was recently published in the journal Biology Letters, with the study title "Unveiling the submerged secrets: bumblebee queens' resilience to flooding."

Sabrina Rondeau's research on hibernating bees led to the discovery of queen bumblebees' ability to survive underwater for extended periods.
The queens' survival underwater is attributed to condensation in stored soil-filled tubes, mimicking their natural underground winter burrows.
To investigate their underwater endurance, Rondeau and her team conducted experiments on Bombus impatiens queen bees and found that 81 percent of the queens submerged for a week were alive after two months.
The queens' ability to withstand long periods underwater may be due to their remarkable lifestyle and an adaptive metabolic response, allowing for metabolic levels to reduce during hibernation.
This research suggests that queens may be able to hibernate underwater in response to flooding or other environmental changes, offering a lifeline for bumblebee populations facing increased flooding events due to climate change.
More research is needed to understand the health effects of immersion on queens and determine whether this ability is common across different species, potentially demonstrating a factor in the resilience of some pollinator species facing multiple threats.