As the year comes to an end for the summer honeybee, so a new season begins for the winter bee.
Unlike a lot of our ‘flying insects’ honeybees don’t hibernate, instead they use the winter months to do a bit of housekeeping; looking after the Queen, getting rid of waste and removing corpses.
Egg laying practically ceases and the population drops. The winter bees, who can live up to ten times longer, have replaced the harder-worked summer bees. Food consumption is at a minimum as there’s little, if any, brood-rearing and practically no work to be done. The winter cluster will only be broken during warm spells or if the colony is disturbed by the beekeeper or predators.
The honeybee is cold-blooded and has no system of temperature control. Bees can raise their body temperature by rapidly moving their wing muscles, in other words shivering. They can also keep their body temperature up by flying, so even in temperatures below freezing they may fly outside the hive for short periods. If the bee’s body temperature falls below about 18°C they’re unable to exercise their wing muscles and when their body temperature falls below about 10°C they’ll eventually die.
As the outside temperature falls below 18°C the bees begin to gather closer together to form a cluster. The cluster forms around the Queen and any brood still in the colony (much like penguins on the ice in the Antarctic). Part of the cluster will be in contact with the food stores. The bees in the middle of the cluster generate the heat by eating honey and exercising their wing muscles. Those on the outer layers form a good layer of insulation to reduce heat loss from the cluster. The cluster expands or contracts to maintain the temperature in the hive.
As you can see despite the winter months and colder climate there’s not much rest in store for bees and there’s still plenty to be done in a bee hive.