14 February 1997

PLIGHT OF HUMBLE BEE

VARROAS decimating effect on the honey bee population makes the survival of the bumble bee increasingly important to farmers and growers, says Richard Jones of the International Bee Research Association, referring to the bumble bees role as a pollinator. The parasite has already seriously reduced bee keepers colonies and is wiping out the feral honey bee population.

"Over the past 30 years several species of bumble bee have disappeared from arable regions of Britain. The progressive loss of wild pollinators could be arrested by careful management of the environment. Nest boxes to encourage colony development could play a part," he says.

Abandoned nests

The abandoned nests of small mammals and birds are among the nest sites chosen by the queen bumble bee when she emerges from hibernation. She will stock it with pollen and nectar, lay her eggs and raise her first batch of workers which will then forage for pollen and nectar too. The queen will continue to lay, and early in the summer all her offspring will be worker bees. Males and new queens are produced later in the season. They will leave the nest and mate. Only the new queens will survive the next winter. They hibernate after digging themselves into the soil.

The home a young queen will seek the following spring will need to be the size of a football – to accommodate a large "family" – and it must be warm, dry, insulated and well drained.

Favoured sites

Holes in the ground, often beside masonry, concrete or rocks which warm up slowly by day and release stored heat at night, are favoured nesting sites. Cavities in buildings, hedge banks or tussocky grassland are also a natural choice. Common species of bumble bee do not collect the bedding material they require, so the chosen hole must contain dry grass or leaves, moss or scraps of paper.

You can tempt bumble bees to nest in your garden by creating a simple nest box and lining it with fresh or used hamster, gerbil or pet mouse bedding. Upholsterers cotton wadding, clean dry moss or fine hay are also suitable, but be sure to avoid any materials that have been treated with pesticide.

Nest boxes may be made from house bricks, large terracotta flower pots and wood – be sure the wood has not been treated – as shown in the diagrams on this page. Note that the sheet of clear plastic beneath the roof of the wooden nest box is suggested to give you an opportunity to observe activity in the nest. It is not essential.

Set out several nests to improve the chances of getting the home you have made occupied, advises the International Bee Research Association who will be happy to supply further information.

Send a large SAE (300mm x 225mm or 12in x 9in) for a copy of the associations catalogue listing its charts, books and field guides, to IBRA, 18 North Road, Cardiff CF1 3DY (01222-372409).