- Wasp population increased on last few years
- Swarms hit UK three weeks later than usual
- Long winter allowed wasps to hibernate, while late summer provided abundant food
- Dog almost died in Dundee after suffering more than 130 wasp stings
If you thought this glorious late summer sunshine was a perfect occasion for picnics, think again.
A plague of wasps has struck Britain - and they're heading for a hamper near you.
Experts today warned that the late spring and long winter have allowed the stinging insects a long and undisturbed hibernation.
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Attack: Billions of wasps are hitting Britian as the late summer brings them abundant food supplies
Experts said that after a few bad years for wasps caused by a run of dreary, wet summers, this year's conditions had given the creatures a boost - contributing to a population explosion that is only starting to unleash its full effect.
Billions of the airborne menaces are emerging from their nests and taking to the skies for their annual feeding frenzy around three weeks later than in previous years.
A bumper crop of fruit this year is likely to keep the creatures going until they either die or go into hibernation after the Autumn.
And with plenty of insects to feed on and a dry end to the summer - not to mention all those sugary drinks lying around by people making the most of a sunny end to the summer holidays - the wasps are more than making up for their late arrival.
Victim: Susan Bruce with her seven-year-old Cocker Spaniel Betty, who were both attacked by a swarm of wasps
A swarm nearly claimed the life of one cocker spaniel in Tentsmuir Forest near Fife Scotland.
The seven-year-old dog, named Betty, went into anaphylactic shock when she was stung more than 130 times.
Owner Susan Bruce, 35, who is a vet with the PDSA animal charity in Dundee, said: 'It was terrifying. They really went for Betty. There were so many that she was completely covered.
'We tried to outrun them, but they got hold of Betty. There were so many wasps in her coat.
Danger zones: the UKWaspWatch site shows London as the area of the UK worst hit by wasps this year
'We tried to fight them off but they stung us too. It was particularly bad for Betty and she collapsed at the side of the path.'
Betty survived after being rushed to the vet, where she was treated with strong steroids and spent the night under observation.
When the vets later posted details of the incident on their Facebook page, several people replied, saying they had also been attacked by wasps.
The hotspot for wasps appears to be in London, according to pest controller Rentokil, which has set up an interactive website to allow users to log wasp sightings and rate them by severity.
Swarm: The insects are amassing in greater numbers and later than in previous years
The capital is followed by Nottingham, Birmingham, Manchester and the South West of England, according to the UKWaspWatch site.
Stuart Roberts, chairman of the Bee, Wasps and Ants Recording Society, said: 'Only four weeks ago I was being asked where all the wasps had gone.
'Firstly, we had a really cold winter which meant that hibernation was more successful than usual.
'The worst thing the wasp queen can have is a warm winter because they fidget and use up the food reserves. I suspect this has had an effect on mortality.
Sticking around: The wasps are likely to remain on the scene until the end of the Autumn, when they die or go into hibernation
'And of course, we have had some quite reasonable weather this year.
'This year I would say the wasps - like everything else in the insect world - are about three weeks late because of the lateness of Spring.
'The late Spring, I suspect, has meant they have just stayed in hibernation for longer, and have been delayed by the cold weather.
'And simply, a warmer drier summer is good for wasps because for a start if you have got a really dreary winter, the queen can't get hold of the food and you get massive mortality.