Urgent warning over food crops being destroyed by rising stowaway pests and non-native frogs invading Britain

SNAKES, frogs and lizards have been caught entering mainland Europe and the UK on potted plants and cut flowers, according to scientists.

These "hitchhiking intruders" could cause severe damage to crops and the countryside, experts at the University of Cambridge have warned in a new study.

Snakes and Italian wall lizards have been imported into countries like the Netherlands undetected among ornamental olive trees.

While a South American tree frog was spotted in a bunch of roses at a florist's shop in Sheffield.

Experts said that if live animals are getting past the border, then much smaller and more invasive insects and fungi could too.

“Adult snakes and lizards are just the tip of the iceberg," Professor William Sutherland, of the university's Zoology department, warned.

"If they’re getting through, what’s the chance of us spotting small insects and fungi – the things that really cause the problems?"

Regulations and border checks are currently in place.

But with potted plants becoming increasingly popular, the sheer volume of them being traded at speed makes it extremely difficult to intercept all the pests and diseases they carry, Dr Silviu Petrovan, of the university's Zoology department and senior author of the study, said.

"Even with the best of intentions, unwanted hitchhikers are getting through customs import checks all the time," he said.

Nevertheless, researchers have said the standards must be "urgently" improved and for data on risks from trade to be collected and shared.

Dr Petrovan, a frog specialist, was called in to identify the South American tree frog from the Sheffield florist.

He thought it was a prank, until it became clear it must have arrived on the cut roses from Colombia via Ecuador.

"If you can get this type of fragile small vertebrate arriving alive in a flower shipment without being noticed at customs, just how hard it must be to detect very small agricultural insect pests or their eggs," he said.

Warmer summers will also fuel the issue, the study noted.

Researchers cautioned that disease-carrying mosquitoes, which previously died in northern Europe's colder winters, may now survive.