Pest controllers are reporting a doubling of wasp-related call-outs this year, while there has also been a big rise in people seeking medical help for wasp stings.

Kevin Higgins, spokesman for the British Pest Control Association, said: "The warm and wet conditions are perfect for wasps. We’re seeing many more multiple wasp nests at single sites this year. You find three or four in an attic. Our members have so much work they’re turning it down.

"The season is lasting longer. It’s at its peak at the moment and with warm weather it could last until the end of September when it only used to last to the start."

Rentokil, the pest control company, reported a 125 per cent national rise on last year in call-outs to deal with wasp nests which are up to four times normal size. NHS Direct also said the volume of calls about insect bites and stings during August was 28 per cent higher than last year.

Reuben Young, of pest control firm Scottish Wildlife Management, said: "It’s definitely been a good year from our point of view. A lot of people have been contacting us with problems with wasps and it’s been busy."

Wasps – or Vespula vulgaris – live in paper nests of up to 10,000 workers, often in abandoned animal burrows, garden sheds, or lofts.

In the late spring the queen will emerge from hibernation and lay eggs which hatch into sterile female workers who build the nest and feed larvae.

Towards the end of the summer the queen lays more eggs which produce male wasps and fertile females which will be the queens of next year’s nests.

Cold weather eventually kills the males, the workers and the foundation queen, but not before the workers do not have to feed the larvae with high-protein food and can go out to satisfy their own cravings for sweet goodies like fruit and jam. As it gets colder, the wasps become more irritable, and this is not helped by them feeding and becoming "drunk" on over-ripe fruit.

But milder spring and winter seasons could mean more wasps are surviving. A Scottish Natural Heritage spokesman said: "

We have seen a very wet, warm season so far and that could mean a greater survival rate. And with the lull in the weather over the past week or so, wasps may have had a greater opportunity to come out of the nests and forage for food. That may have brought a short-term blip in the number of wasps, as they are all coming out at the same time."

WHILE not regarded as particularly hostile, wasps will sting if annoyed or when defending their nest.

When they are not after your lunch they feed mostly on other insects or carrion. The answer to the question posed by the book Does Anything Eat Wasps?, is quite a lot, including birds.

Although considered a nuisance, wasps do have their uses – some have been cultured and used in the biological control of agricultural pests as they prey on other insects.

A wasp uses its sting for killing prey, but it can also use it very effectively for defending itself. The sting has associated glands which produce venom. A sting can be very painful, but is normally not dangerous. But in some cases more serious effects occur and repeated stings can cause anaphylactic shock which can prove fatal. Symptoms include respiratory distress, swelling of the face and vomiting with abdominal pain. Last year experts warned of the dangers of wasp stings after two men in England died from anaphylactic shock.

According to research by insurance firm esure, more than a million drivers a year crash because of insects flying into their cars.