Bees in Winter

Numerous people have asked me if bees hibernate. The answer is no, but they do dramatically change their behaviour and physiology.
In the summer, a worker bee will live for about 6 weeks. The queen is continuously laying eggs through the summer (up to 2,000 per day!) and so new workers are being produced. The queen stops laying in the winter and so the workers have to survive until Spring when she starts laying again. In late August and early September the workers feed heavily on pollen. This builds up their stores of fat, protein and glycogen. In this way they can live for up to 6 months.
Bees can survive in low temperatures as long as they are dry. As the temperature drops in Autumn they begin to form a rugby ball shaped cluster within the hive. This reduces heat loss - much like the penguins in the film "March of the Penguins". The bees at the centre of the cluster eat honey and create heat as they exercise their internal muscles. A cluster temperature of 31 C with an outside temperature of - (yes minus!) 28 C has been recorded. Without any eggs or larvae to care for, the cluster temperature is normally 20-30 C. They only leave the hive on warmer days for cleansing flights
There are a number of factors that determine whether a colony survives the winter. Last winter losses were 20% nationally. I have done all I can this year to help Genesis colony survive - I really hope they make it.