It’s not simple being a queen — a bumblebee queen, that’s. To start out her colony within the spring, an expectant queen should first survive the winter by hibernating alone within the soil, the place she’s susceptible to hazards like floods.
It seems these bee queens are royally as much as the duty. In a serendipitous discovery, researchers have discovered that hibernating bumblebee queens can survive being submerged in water for as much as every week.
Bee biologists Sabrina Rondeau and Nigel Raine had been learning how hibernating queens reply to pesticide publicity (SN: 3/29/12). Condensation within the fridge storing the dormant bees in Raine’s lab on the College of Guelph in Canada unintentionally triggered 4 of the vials housing queens to flood, the pair describe April 17 in Biology Letters.
“I used to be very involved at first,” says Rondeau, now on the College of Ottawa. “I assumed, in fact, they had been lifeless.” However to her nice shock, when she picked the queens up with forceps they began fidgeting — undeniably alive.
Rondeau and Raine determined to check extra rigorously simply how waterproof bumblebee queens are. They gathered 143 widespread japanese bumblebee queens (Bombus impatiens) left over from one other experiment (these bees can be found commercially, and weren’t collected from the wild). Seventeen queens served as controls and weren’t submerged underwater, whereas the others had been both submerged or left floating on the water’s floor for both eight hours, 24 hours or one week. All of the bees had been housed in particular person vials and saved at chilly hibernation temperatures.
This was meant to imitate attainable real-world flooding situations, the place a queen’s hibernation chamber might doubtlessly be stuffed with water or solely partially submerged. How typically that occurs is unknown. Observations of bumblebees overwintering within the wild are scarce, however queens have been discovered to usually desire sloped floor and sandy soils that will not be vulnerable to flooding. Even so, it appears the bugs are ready for catastrophe.
It turned out that the 4 queens who survived unintentional fridge flooding had been hardly outliers. Of the 21 queens that had been submerged for seven days after which allowed to renew hibernating, 17 had been nonetheless alive eight weeks after their aquatic ordeal. This price of survival was not statistically totally different from that of the 17 bees that had been by no means submerged — 15 of them survived to eight weeks.
When first pulling the queens out of the water, Rondeau says they seemed like a bee that you simply’d fish out of a swimming pool. However after a day again within the fridge, “they’re fluffy once more, lovely, like nothing occurred,” she says. “Extraordinarily shocking.”
The discovering raises many extra questions, Raine says. “Does it have an effect on their skill to discovered colonies? Does it have an effect on reproductive success of the colony?”
There’s additionally the query of how the queens handle to outlive being underwater for therefore lengthy. Many grownup bugs have variations to assist them keep away from drowning, like closing their spiracles — the physique openings they breathe by means of — to stop water from getting in. Rondeau suspects that the lowered metabolism of hibernating queens additionally helps, as they will go longer with their spiracles closed than they might in the event that they had been absolutely awake and energetic.
“What it actually exhibits is how little we all know — and the way a lot there may be to study — in regards to the bumblebee life cycle,” says Elizabeth Crone, a biologist on the College of California, Davis. “Their interactions with flowers are top-of-the-line studied phenomena in ecology. In distinction, we all know little or no about their nesting, hibernation and replica.”
