Hunts across the West are engaged in a ‘nationwide criminal conspiracy to encourage and sustain fox populations in order that they can be hunted’.

That was the claim by anti-hunt campaigners after a undercover operation found that artificial earths in hunting areas are still being maintained to make sure there are foxes to hunt.

The covert surveillance operation was undertaken from July to October this year by teams of monitors from the League Against Cruel Sports, and targeted hunts the length and breadth of England.

Hunts have denied that the artificial fox earths, the maintenance of them and video footage of people bringing food for the foxes are anything to do with them, and said the claimed evidence “proves nothing”.

The revelation that artificial earths, to encourage foxes to breed, are maintained to keep fox numbers up dealt a major blow to the hunting lobby’s argument before the 2005 ban that foxhunting was necessary as a form of pest control. That they are still being maintained six years after the ban, claims the League Against Cruel Sports, shows that hunts are still routinely breaking the ban and intentionally hunting foxes. Monitors discovered three artificial earths in woodland around Stow-on-the-Wold and Cold Ashton in Gloucestershire, on land regularly hunted by the Heythrop Hunt. In Wiltshire, close to the Badminton Estate, the monitors discovered three more artificial earths were still being maintained.

In other locations in the country, artificial earths were discovered with metal grilles hanging near them, which the league said was to make it easy to quickly block them up on hunt days.

But the league claimed the most damning evidence came in Dorset, where hidden cameras filmed an unknown man dragging a barrel full of offal and dumping it close to a newly maintained artificial earth, inhabited by foxes.

The spot between the villages of Cattistock and Evershot in Dorset, is owned by the Hon. Charlotte Townsend, the master of the Cattistock Hunt. Hidden cameras filmed a man dumping a barrel of animal by-products in the wood and filmed the foxes taking the food away.

The league’s chief executive Joe Duckworth said the findings were the “tip of the iceberg”, given that 87 per cent of the hunts they chose to look at had artificial earths in their regularly hunted woodland. “In just a short space of time our investigators have shown without a shadow of a doubt that there is a determined effort among the hunting community to keep fox numbers artificially high.

“The evidence points at a pattern of extreme behaviour which I am convinced goes far and beyond the evidence obtained by the league in this investigation and may be connected with other wildlife crimes such as hunting with dogs,” he added.

League chairman John Cooper said: “This evidence points to a nationwide criminal conspiracy by foxhunts to encourage and sustain fox populations in order that they can be hunted.”

The league admitted it cannot definitively prove that the people who maintain the earths or feed the foxes are connected to local hunts.

The joint master of the Cattistock, Will Bryer, said the Cattistock was the victim of a ‘smear campaign’. “We refute these allegations, they’re ridiculous,” he said. “Artificial earths have been around since the beginning of time but we have no use for them now. If someone is putting food out for foxes, it’s not us.”

And Tim Bonner, from the Masters of Foxhounds Association, said the hunts had nothing to do with artificial earths. “The earths are not only used by hunts. They are also used by gamekeepers to locate foxes so they can find them and kill them,” he said.