The ants are said to be more attracted to electricity than food and drink
Ants believed to have a "kamikaze attraction" to electricity have been discovered in one of England's finest National Trust gardens.
Colonies of Lasius neglectus, the so-called Asian super ant, have being found at Hidcote Manor, near Chipping Campden, in Gloucestershire.
It is thought to be the first recorded sighting in the UK, although they have been spotted in mainland Europe.
They are naturally drawn to electrical currents so can pose a fire risk.
The species was first identified in Budapest 20 years ago. The ants look like a common black garden variety.
English Heritage and the National Trust carried out investigations into infestations within the Hidcote estate to identify them as lasius neglectus.
The Asian super ant is highly-dependent on aphid honeydew and is associated with a wide range of tree species.
Their compulsion to follow electricity is stronger than their need for food or drink.
Swarms of ants around electrical cables can cause blackouts.
Brian Ridout, English Heritage entomologist and architectural conservator, said they may have gone unnoticed for some time.
"The behaviour of the ants didn't agree with that of any known UK species," he said.
"Our suspicions were confirmed when samples were sent to the Universitat Autonoma de Barcelona which has been studying major infestations of them in Spain.
"They look just the same as the common black garden ant, although there will be ten to a hundred times as many of them."
The National Trust said 35,000 ant carcasses were found in one electrical junction box at Hidcote.
Simon Ford, nature conservation advisor for the National Trust in Wessex, said: "The ants themselves pose little direct threat to us as they don't bite people or pets.
"Their habit of creating super-colonies means they pose a threat to native species by out-competing them for food and space, and their attraction to electrical circuitry means they could pose a fire risk.
"Researchers have feared for several years that this species would make it to the UK, and while the Hidcote colony is the first case recorded, it is not clear if it is the first in the UK or indeed that it is the only one.
"It is very likely the ants are more prolific."
The super ant is resistant to traditional insect poison so the National Trust is now working with pest controllers to investigate other options, including bait systems.