Strength in numbers of clustering bees


Strength in numbers of clustering bees

At this time of year, all bees should be fed and treated for the varroa mite, and settled for the winter, although on dry warm days they are still bringing in pollen and probably nectar mostly from ivy.

Ivy is a wonderful plant for honeybees in the autumn.

Beekeepers are often asked if bees hibernate? They don’t. They form a cluster. Clustering is necessary for self-preservation.

Bees are poikilothermic and all that means is that they assume the temperature of their surroundings, so if the temperature drops to zero degrees, a bee’s body temperature will go to zero degrees and it will freeze to death.

Colonies of bees have adopted a method to overcome this deficiency by gathering together in the hive to form a heat reserve.

Bees start to cluster at an ambient temperature of 14C, forming a ball with the comb running through it, the top of the ball will be in contact with the store of honey at all times, and below this where the combs are empty, the bees will creep into the cells, making the cluster almost solid, the cluster has an outer shell of bees which can be very dense ranging in thickness from 25mm to 75mm thick.

The outer shell temperature must be maintained at 7C , (below this the outer bees will drop off and die), to maintain the critical temperature as the cluster contracts and expands.

The temperature in the centre of the cluster ranges from 20C to 30C when there is no brood in the hive, which usually happens around December/ January, and when the queen starts laying next February or so, temperatures will have to be maintained at 35C.

You may ask how do bees maintain this temperature? Well, they cluster to reduce their surface area thereby reducing heat loss.

Bees create heat within their body by muscular activity and then within the cluster. The muscles used are the indirect flight muscles. To flex these muscles the bees need to consume honey, so the cluster needs to be near food at all times.

It is very important not to disturb the cluster, even taking off the roof for a quick look can cause a rise in temperature within the cluster by up to 6C, the bees realise there is some interference, and break the cluster to investigate and fly out.

Excluding mice from the hive is paramount, apart from the damage they do to the comb, the disturbance to the cluster can result in weakening or even loss of the colony.

The modern open mesh floors have very big openings, why I don’t know, I’m sure the makers are not beekeepers, so they need a mouse guard which is pinned across the opening, and has bee space for the bees to exit and enter.

Clustering is the nucleus for next year’s honey crop.

Some important points for wintering: Make sure the bees have sufficient food to keep them going until next spring.

Keep out unwanted visitors like mice and check there is no damage after high winds.

Dampness, too, can be a serious problem, make sure there are no leaking roofs, as bees can withstand cold, bur not wet and dampness.

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