Thermal Images of Winter Bees

I had the opportunity to borrow a FLIR E30 thermal imaging camera from a friend about a week ago. We used the FLIR to take some images of our hives in Winter.
The lighter zones in these images show the heat signature of the bees winter cluster. Honey bees form a football-sized cluster with the queen at the center. The worker bees shiver their flight muscles to generate heat and keep her warm all winter long. The cluster moves through frames of stored honey — working from the bottom to the top — to generate enough heat to survive our Midwestern winters.  (It was several degrees below 0°F when we captured these imsges.)

We like seeing the cluster low in the hive. That means there’s lots of honey still stored above them. For the hives that show the colony clustered high in the stack, we will add some sugar cakes to help them make it through the winter.