Wasps

Pest Name: Wasps - Vespidae, eg Vespula vulgaris / Vespa germanica

Markings: Variously marked, with characteristic bans of yellow/orange and black.

Location: A wide range of man-made and natural structures from soffit to sycamore.

Detection: Visual sightings of adults.  Complaints of stings.  The nest.

General Information:Size - 9-19 mm overall body length.  Two pairs of wings and a noticeable  'waist'.

Wasps provide much work for the pest control industry during the summer and autumn months.  They are social insects, forming colonies with usually one queen, and they live in nests made of paper-like material.  Their habit of building nests in homes and factories, and their feeding habits, seeking out sweet and fermenting matter, bring them into direct conflict with man.

Biology: The season begins with a young, fertilised queen that has managed to over winter.  She emerges from hibernation during April, searches out a suitable nest-building site and creates a pilot nest, or 'cell' from chewed fragments of wood mixed with saliva.  Into individual segments of the cell she lays up to 20 eggs, and cares for them through development, feeding them on insects etc.  These form the first brood, hatching into sterile worker wasps.  They then take over the task of enlarging the nest and tending the next and subsequent batches of eggs laid by the queen.

A typical nest is about a foot (30 cm) across and will contain about 4,000 wasps, but most pest controllers can tell a tale of a 'mega-nest' many feet across, packed with angry workers.

At the end of the season, male wasps and young queens emerge and mate.  The fertilised queens fly off to over winter, and thus begin another cycle.

Reasons for Control: Wasps are mainly controlled for their nuisance value, although there is some evidence that they may be vectors of disease, caused by their feeding habits in dustbins, waste skips and also on carrion. 

There is no need to discuss the sting of a wasp here, suffice to say it can be extremely painful and prove life-threatening to those susceptible to venom.  Over 50% of people who die from stings/bites by venomous animals are killed by the (not so) humble wasp.