Tiny beetle causes big problems among the moorland heather

The 6mm-long heather beetle and its larvae are also threatening other large tracts of heather in the North Pennines.

The infestation was first noticed in 1999 and worsened last summer. The beetle eats heather foliage, bark and roots, turning whole moors a rusty red colour.

English Nature says attacks by the beetle are not new, but have never been seen on such a scale before.

Mr Richard Wilson, English Nature conservation officer in Leyburn, said the beetle was not only threatening the economic viability of the moors, but also an internationally important habitat.

"Upland dry heath and blanket bog are largely confined to Britain and the habitat that they provide for bird life, including merlin, short eared owl and golden plover, not to mention the grouse that underpin the economic viability of these uplands, is vital," he said.

In the past, gamekeepers had helped the heather recover by burning the affected areas.

"Yet with the scale of the problem we are witnessing today, that would mean burning whole moors, which simply isn't viable on either economic or ecological grounds," said Mr Wilson.

Although the climate has been a factor in the scale of the current infestation, the exact cause is not known so little can be done to overcome the problem.

The Game Conservancy Trust has joined forces with the northern uplands moorlands regeneration project and sent a questionnaire to all moorland owners, managers and gamekeepers to discover the extent of the problem.

Mr David Newborn, senior research scientist with the trust, said that if the problem continued, a research programme would investigate possible methods of control.

Conservationists and moorland owners are hoping for a natural solution, either through a dry spring or through a parasitic wasp which grows inside the beetle larva, killing it off from the inside.

Other remedies such as pesticides would only kill off other invertebrates that are vital to the survival of moorland bird life