A TINY beetle is threatening the future of Craven's renowned heather moors after attacking plants for the third summer running.

The heather beetle has infested up to a quarter of the 50,000 hectares of internationally important upland moors in the Yorkshire Dales on a scale of attack never seen in the area before.

The infestation was first noticed last year, but worsened this summer as large areas of heather were killed by the beetle which eats foliage, bark and roots, turning whole moors a rusty red colour before they die off.

Richard Wilson, English Nature conservation officer, said: "Not only is this attack threatening the economic viability of the moors, it is also threatening an internationally important habitat.

"We haven't reached catastrophe, but we have certainly reached minor disaster.

"Upland dry heath and blanket bog are largely confined to Britain and the habitat they provide for bird life, including grouse that underpin the economic viability of these uplands, is vital."

Mr Wilson added: "In the past, gamekeepers were able to promote the recovery of heather 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."

Moors in Wharfedale have been affected, and Mr Wilson said there would undoubtedly be a local loss of heather hillsides.

"Heather will just disappear from some hillsides. When the beetle affects small patches of heather, you can burn it and it will regenerate naturally, but you can't burn whole tracts of moor.

"We just have to wait and see what happens in future years, but it is entirely possible that depending how bad it gets some estates will feel they cannot wait three to 15 years for the heather to possibly recover."

The cause of the infestation is unclear, although climatic factors play a part and until the cause is known, there is little to be done to address the problem.

The Game Conservancy Trust has joined forces with the Northern Uplands Moorlands Regeneration Project in sending a questionnaire to all moorland owners, managers and gamekeepers to establish the true magnitude of the heather beetle problem.

Trust senior research scientist David Newborn said: "If the problem continues a research programme will be initiated to explore possible methods of control."

Conservationists and moor owners are hoping for a natural solution, either through a dry spring which will limit the survival of eggs, or in the form of a parasitic wasp that grows inside larva, killing it off.

Other alternatives, such as pesticides have been ruled out because they would kill off other invertebrates vital to the survival of moorland bird life.