Thieves have struck at the last stronghold of England’s rarest ant species a conservation charity has announced today.

Devon Wildlife Trust (DWT) says a nest belonging to narrow-headed ants has been stolen from its Chudleigh Knighton Heath nature reserve in south Devon.

A single nest can hold a colony of between 1,000 and 5,000 ants, along with one or more breeding queens which can live for as long as 25 years.

The theft was discovered in mid-October when conservation researchers carrying out regular checks on the ants found a hollow where a known nest had been. The surrounding ground showed clear signs of digging with a spade.

Chudleigh Knighton Heath is a Site of Special Scientific Interest (SSSI), while narrow-headed ants are also a Section 41 species, Nationally Rare, and Near Threatened on the IUCN Red List of species, so removing the nest is against the law.

The theft has been reported to Devon and Cornwall Police. DWT is asking anyone who might have information about the incident to come forward.

The nature reserve is the last stronghold for the narrow-headed Ant in England. A small number of colonies still exist in Scotland, including on the Royal Family’s Balmoral Estate.

The species, which is named after the distinctive ‘pinched’ look to their heads, was once much more widespread but has seen its numbers dwindle over the past 100 years as its favoured heathland homes have been lost to development and agricultural change.

Julia Balfour the DWT’s species recovery officer said: “The removal of an established nest is a significant loss for this species. Narrow-headed Ant colonies develop slowly, and each mature nest, with its long-lived queens, represents many years of growth that cannot quickly be replaced.

“This is a crime every bit as serious as illegal raids on wild bird eggs. It shows the pressures that our nature and wild places are under.

“Our most recent survey recorded 142 active nests on the nature reserve, so every nest matters. This is the last population of Narrow-headed Ants in England, and losing even one colony sets back years of careful work by our staff, volunteers and partners.

“This incident makes us even more determined to ensure that our work to secure their future is a success.”

PC Lucy Wyatt is part of the rural affairs team at Devon & Cornwall Police. “Sites of Special Scientific Interest are legally protected and it is a criminal offence for any person to intentionally or recklessly damage, destroy, or disturb the protected area, she said.

“If you’ve seen anything suspicious in recent weeks or have any information that may assist us with our investigation, please contact us by calling 101 or filling in a form on the Devon & Cornwall Police website, quoting crime reference: 50260284768.”