Winter temperatures have arrived; the low temperature for today is 21 degrees F! You might be inclined to think that these winter temperatures are hard on honeybees and that they’d rather have mild, warmer winters. But you’d be wrong! Our honeybee, species originally brought over to North and Central America by early explorers from Europe about 500 years ago, evolved with winters. They have amazing traits that allow them to survive prolonged freezing temperatures. Each healthy honeybee hive has 20-30,000 individual honeybees that survive in the hive by lowering their metabolic rate, eating honey stores, and vibrating their wings to stay warm. They exist in what is called a “winter cluster” with all the bees huddling into a ball shape rotating into the middle of the cluster, then out to the outer boundary of the cluster over and over again. This allows for warmth to be generated, as well as high carbon dioxide levels to build, which helps maintain those lower energy-saving metabolic rates. A healthy hive can maintain that winter cluster for months on end, surviving on only 1/3 of a pound of honey per day for those 20-30,000 individual honeybees.
What happens when we have an unusual warm spell in the middle of the winter months? The honeybees get confused and think that spring has sprung. They break up that winter cluster and start leaving the hive to forage for nectar, only to find that nothing is blooming! This wastes an incredible amount of energy, drains honey stores, and puts the hive at risk of not surviving until spring. The optimal daytime temperature range for European honeybees is 32-41 degrees F, but as long as winter temperatures stay below 55 degrees F, the winter cluster is maintained and honeybees should handle the winter just fine.
Below photo of a winter clustered honeybee hive is courtesy of www.scientificbeekeeping.com. The founder of Scientific Beekeeping, Randy Oliver, has been an incredible source of data-driven beekeeping guidance to the Beekeeping Association at the UofU since the club’s founding.
The Buzz at the UofU Beehives
By Amy Sibul, Faculty adviser to the Beekeeping Association at the University of Utah