Tuesday, December 8, 2009
Honey Bees Cluster
When outside temperatures drop in the fall, the bees form a cluster inside the hive to maintain heat. The cluster generally maintains a temperature of about 68 degrees. The queen bee stops laying eggs and rests in the center of the cluster. Clustered bees actually generate heat by eating their high-energy food, honey, and then vibrating their flight muscles to raise their body temperature, a unique feat for an insect. The cluster also adjusts its internal temperature by expanding or contracting as needed. However, if the outside air temperature is very cold, the bees must consume greater amounts of honey to warm the cluster. The bees are not wasteful; they don’t attempt to warm the hive space outside the cluster of bees. The structure of the honey bee nest is itself very favorable for winter survival. The sheets of comb make good insulation. As the honey is eaten from the cells, the cells of dead air become an exceptionally effective barrier from the cold. However, during very cold weather, honey bees often cannot break away from their tight cluster to feed. The colony may starve, even when honey is available nearby. Click the picture. Opening the hive on a cold morning, I disturbed a late fall cluster of bees.