Bumblebees Can Survive Underwater 0 7

Research has shown that queens of the common eastern bumblebee (Bombus impatiens) can remain underwater in a state of hibernation for up to a week. Considering that bumblebee queens typically burrow into the ground for winter, scientists suggest that this trait may help them survive during floods in the wild.

“We know that about a third of all bumblebee species are currently at risk of extinction, but this does not apply to the common eastern bumblebee,” said Dr. Sabrina Rondo from the University of Guelph in Canada, adding that the team aims to determine how flood resilience affects the health and viability of these insects.

This discovery was unexpected

Rondo and her colleague, Professor Nigel Raine, made this discovery accidentally when water entered containers with hibernating bee queens in the laboratory.

After the scientists noticed that the bumblebees survived this incident, they decided to conduct a full experiment. The study involved 143 queens of the common eastern bumblebee in hibernation, each placed in a separate plastic tube with a moist top layer of soil. The tubes were sealed with perforated lids and stored in a dark refrigerator for a week.

Once the researchers confirmed that the bees remained alive, they kept 17 tubes as controls and added cold water to the remaining 126. In half of these tubes, the queens floated on the surface, while in the others, they were submerged underwater.

In both cases, one-third of the tubes were left for eight hours, another third for 24 hours, and the final third for seven days, simulating different flooding conditions. The team then transferred the bees to new tubes and monitored their survival.

The results showed that survival rates were similar regardless of the duration and conditions under which the queens were kept — 88% of the controls and 81% of the queens that were underwater for a week survived after eight weeks. However, heavier queens had a better chance of survival.

Scientists note that such results are unusual, as most insects that overwinter in the adult stage, including many ground beetles, cannot cope with immersion in water and are forced to leave floodplains to survive.