Anyone who has ever tried to get rid of a mole from the garden may find it hard to believe but the species is feared to be on the wane.

Moles are notoriously hard to remove once they have infested a field or lawn, but a lack of the invertebrate species that they eat may be stopping them in their tracks.

Conservationists are concerned that this may be a sign of a deeper problem in Britain’s ecosystem so they have started a project to encourage the public to help to conduct a survey to establish where the animals can still be found. The best clues, of course, are molehills. The mounds of earth thrown up to the surface, often over manicured lawns, are the most visible sign of moles and are an ideal indicator of their presence.

By collecting sightings from all over the country the People’s Trust for Endangered Species hopes to build up a detailed map of where they can still be found.

Jill Nelson, the chief executive of the trust, recognises that to many gardeners and equestrians, whose horses can break their legs by stepping on molehills, moles are anathema but she defended the animals as an important part of the ecosystem.

“If moles are in trouble in an area it’s an indication that the things they are feeding on might be in trouble, which may in turn point to some trouble with the land. Ultimately, it will affect us,” she said.

“The only thing I can say for gardeners is, ‘If you have moles you obviously have very healthy land’. The fact your lawn has been dug up is perhaps unfortunate but at least it’s a healthy environment,” she added.

Moles can be a friend to gardeners because they eat pest species of insect larvae including leatherjackets, cockchafers and carrot flies.

Ms Nelson added: “Seeing a molehill is the only reliable means we have of recording the presence of moles. By gathering this information from surveyors across the UK we will be able to produce a distribution map of moles and judge whether there are areas where they are scarce.”

The MoleWatch survey runs until the end of the year and volunteers have already recorded 16,000 sightings of molehills. For details go to www.molewatch.org.uk.

Secretive lives

— Moles live virtually all their lives underground. They come to the surface only in the breeding season to collect leaves for nests

— They like earthworms and beetles. An adult eats almost two thirds of its body weight each day They create a network of tunnels into which invertebrates fall. The mole’s saliva paralyses earthworms so that they can be stored in specially constructed larders

— There are 42 species worldwide. Up to 25 can live in 1 hectare

— At the start of the 20th century more than 1 million moleskins were sold in London annually and 12 million were being sent to US to be used in breeches, waistcoats and ladies’ coats

Source: PTES, Encyclopedia of Mammals, Times database

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