Wasps

Description

Wasps are probably the most familiar and generally disliked of all British insects.  Their bodies bear the characteristic black and yellow bands and have a narrow waist in the middle of the body.  They vary in size from the worker which is 10-15mm in length, to the queen, which is 20mm long, and they have two pairs of wings which lock together.  The needle-like sting is possessed only by the females and is concealed near the tip of the abdomen.

Distribution

Several species of wasp exist in the UK but the most abundant are the Common Wasp and German Wasp both of which are widely distributed.  Both species nest underground or in the cavities of trees, walls and buildings.

Significance

Wasps can be a nuisance but are not responsible for the spread of disease.  Although they are generally disliked because of their sting, this will only be used by most species when the wasp is aroused or frightened.  Wasps are responsible for causing serious damage to ripened fruit and are generally a nuisance when attracted to sweet smelling foods.  Their benefits, however, are not so widely appreciated, for in the spring and early summer, wasp grubs are fed on other insect pests.

Life cycle

The queen emerges from the nest in the autumn and, after mating, selects a suitable site for hibernation.  Late in the following spring the hibernation comes to an end and the surviving queens select a nest site.  The nest is usually located either in the ground, or in the roof cavities, and is built up from wood pulp which is moulded into the outer shell of the nest and contains many internal chambers.  The queen lays an egg in each of the chambers and these hatch into larvae which are fed by the queen on dead insects.

When fully grown, the larvae pupate and from the pupae sterile workers emerge.  These workers assist in rearing new larvae and the new queens.  Towards the end of the summer the queen lays a number of eggs which produce male wasps and these mate with the new queens.  As the weather becomes colder in the autumn, all the wasps die, except the new queens which fly away to find hibernation sites.  The old nests are not recolonised the following year.

Control

Wasp nests should always be treated by a professional as they pose a particular danger to you and your family.