False widow spiders are 'not aggressive' towards humans
A school in Gloucestershire has closed for the day because of an outbreak of Britain's most venomous spider.
The Dean Academy, in the Forest of Dean, said it "had identified an issue with false widow spiders" in its ICT block and other areas of the site.
Conservationists believe a change in the climate could be the cause of an increase in sightings of the species.
The false widow (Steatoda nobilis) is the most dangerous of the 12 species of biting spider known in Britain.
There have been no reported deaths from its bite in the UK.
Stuart Hine, manager of the Insect Identification Service at the Natural History Museum, spoke to Newsbeat about the false widow spider.
Is the false widow spider dangerous?
"It's not deadly at all. It's a species which can bite and does bite.
"Generally speaking symptoms are no worse than a bee or wasp sting and in truth you're more likely to be stung by a wasp than you are to be bitten by this spider."
Are the false widow spider numbers increasing?
"It certainly seems it from some media reports. It's a spider which is expanding its range in the UK. It's done so very quickly in the last 15 years.
"One of the reasons is it likes the environment of our homes, gardens and urban environments. It makes its webs and survives there very nicely.
"It loves a south-facing conservatory where it will live in the very hottest parts of it and they can be very abundant in and around our homes."
Is the false widow aggressive towards humans?
"They're certainly not out to get us. It's not aggressive.
"When people do get bitten, and this is very infrequent generally speaking, it's because they've got inside clothing and they've been pressed against the skin when we put that on, or occasionally in bedding. That's the only circumstance that they bite.
"It's more usually the males at this time of year that wander into homes and they're looking for female spiders.
"The likelihood of a bite is very low and usually symptoms are not that severe."
Where might you find a false widow?
"Females very much stay in their webs. They're a great spider for that.
"They make a web, they expand it, they build on it and they can stay there for up to three years.
"They won't harm us at all and they do some great work in ridding our homes of flies and wasps and arguably some other nuisance insects."
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