Britain faces black widow spider invasion as hordes of alien bugs now thrive in our warmer climate

Deadly black widow spiders could soon establish colonies in Britain due to warmer weather, experts warned today.

They said it was ‘only a matter of time’ before the extremely poisonous American arachnid join the 500 other alien bug species invading the UK each year.

New inhabitants, which ‘hitchhike’ here in food and plant imports, already include its cousin, the false widow spider.

Black widow

Threat: The arrival of black widow spiders is 'only a matter of time', experts say

Researchers believe many arachnids and insects are now able to survive and spread thanks to the UK’s increasingly mild climate caused by global warming.

And some recent arrivals, such as Asian Harlequin ladybirds and leaf beetles, are already threatening to wipe out some of Britain’s native species.

Conservation group Buglife wants import rules to be strengthened to stem the tide of alien species invasion.

Its director Matt Shardlow told Mail Online: ‘Other countries in the world, such as Australia and New Zealand, take great care about what biological material they allow in, because it can contain pests that can damage our goods, our livelihoods, our health and our biodiversity.

‘Currently in the UK, we have a laissez-faire attitude - there is an open licence for people to bring in dangerous pests.

‘The only course of action we have is to write a warning letter to foreign governments.’

Recent years have seen serveral of reports of ‘black widows’ being spotted in bunches of bananas and other fruit by members of the public.

Many such sightings are thought to have its similar-looking, but much less dangerous cousin, steatoda paykulliana, which is commonly known as the false widow.

Originally from southern Europe, it was first seen in Britain as early as the 19th Century but was not thought to have established colonies.

Now it has established itself around Plymouth, Devon, and, due to milder weather, it could spread more widely across the south of England.

‘If there was a warm period they would be able to survive, but a cold snap would kill them off,’ said Stuart Hine of the Insect Identification Service at the Natural History Museum in London.

‘But now, our increasingly warm climate is starting to suit many more spiders - and once they come in, they are able to stay put.’

He suggested that the black widow could soon follow suit.

‘There is no great reason that they wouldn’t survive here now - winters are now mild enough,’ he said.

‘It really is only a matter of time.’

But a spokesperson for the Department for Environment, Food and Rural Affairs (Defra) said that a new strategy was in place to ‘tackle the threat to the UK’s native biodiversity from unwanted pest species which have hitchhiked into the UK on plants’.