What happens to bees in the winter?

During the winter months, honeybees cluster together to stay warm inside the hive. They do not hibernate like some animals. They still function (at a much slower pace) and move throughout the hive as a coordinated colony consuming the honey that they stored the previous summer.

Contrary to what you may think, cold is not the biggest threat to bees over the winter. In fact, it is moisture and condensation that can kill entire colonies of bees.

Bees are quite good at staying warm all winter long. Each honeybee can detach her flying muscles from her wings and use those same muscles to generate heat by vibrating. The bees then cluster tightly within the hive. It remains a balmy 35° Celcius at the centre of the cluster, all winter long.

Because of the warmth inside the hive, without adequate ventilation, condensation will form on the top of the hive and then drip down on top of the cluster. It’s this moisture that will kill bee colonies over the winter. Proper ventilation is crucial to the survival of honeybees when the weather is cold outside.

Adding ventilation

There are numerous ways to add ventilation to a hive. When adding ventilation to my hive, I wanted to add sufficient ventilation while still protecting my hive from robbing¹. After researching online and listening to others at my local beekeeping association, I came up with the idea of using a paint stir-stick on top of my inner cover in order to add a nice gap under the outer cover, sheltered from the elements and small enough to guard against robbing.

I simply cut up a paint stick into short lengths and then glued one small portion to the four corners of my inner cover. Since this portion of the inner cover is not considered “inside” the actual hive, it’s unlikely that the bees will fill the small gaps with propolis the way they would do if the gap was on the underside of the inner cover.

The whole process took only a few seconds to cut and glue the the paint stick and the cost was free, since you can pick up these sticks at just about any hardware store that sells paint.

Paint stick cut up
A honey bee on stir stick ventilation
Paint sticks glued to inner cover

¹ Robbing occurs when other wasps, honeybees or insects get into the hive through an unguarded entrance and steal valuable honey from within.