Pest Of The Week – Bumble Bees

Bumble Bees are a familiar sight during the summer in town and in the country. They are attractive insects and more amenable than honey bees as they do not sting unless really provoked. Bumble Bees are round and furry, with distinctive black and yellow markings. The common species are 19 – 38mm long. They make a loud buzz which can be disconcerting. They do not swarm.

Creation and Life of a Colony:
In Spring, the large Queens will be seen flying about looking for a suitable place to start a colony. Bumble Bees prefer dark, dry places such as old mouse nests, compost heaps, spaces under sheds and houses or paving stones and even on the ground in rough grass. The Queen has to start the colony on her own. She lays eggs which will develop into workers. She initially does all the work of making wax cells for the eggs, collecting food (nectar and pollen), feeding the larvae and defending the nest. If the weather is very wet or cold, her work may end in failure and she must start again. The colony is small compared to a hive of honey bees.

On sunny days in February bees can be seen looking for food in flowers such as willow and crocus. From April the workers start emerging. They are similar to the queen but smaller. The males come later and may or may not be the same colouring. Lastly, new queens are born in July & August. All groups of workers can be seen in June and July but by August and September usually only the red tailed brown and carder species remain. The colonies die out and the new mated queens find a suitable sheltered/dry place to overwinter. As a rough guide, the nests of common species can usually be found in a covered locality, such as underground, in or under sheds within buildings etc., and are vacated by early August.

Pollination by Bumble Bees:
Bumble Bees are important pollinators but they have been on the decline in recent years and farmers have had to change the crops that they grow, such as red clover, as they were getting insufficient pollination. They are good pollinators of field beans and rape. In commercial glasshouses Bumble Bees are kept, in special boxes, for pollinating tomatoes, strawberries, peppers etc. This is made possible in all seasons by immersing the queen in CO2 for 24 hours, after which she thinks that spring has come and starts nest building, whatever the season.

In our gardens they are essential, along with honey bees, for pollination.

Removal of a Bees Nest:
A bumble bee nest should not be disturbed or destroyed because of its high pollination value. However, if a colony is in a very inconvenient place, it can be removed and relocated. It must be about a mile away or the foragers will return to their old home. It is beneficial to leave a nest.



For advice or further information on bumble bees in Edinburgh, Glasgow, Aberdeen, Dundee or Perth, call GRAHAM pest control today and we could help.