A PLEA for co-operation by dog-owners during the lambing season has come from Dartmoor National Park Authority.

The authority, in conjunction with the RSPB and the Ministry of Agriculture, Fisheries and Food, has asked that dogs be kept under close control during the critical period for lambing and calving on the moor.

The DNPA is also asking for co-operation from letterboxers in avoiding certain moorland areas to prevent disturbance to ground nesting birds.

Sue Halse, Moor Care officer, said: 'Many visitors and local people exercise their dog when enjoying Dartmoor. Although a dog may not be actively chasing livestock, its presence can still cause disturbance.'

She said ewes and cows are particularly vulnerable in the lambing and calving season.

'A frightened animal may abort or abandon its young — a tragedy for the animal and a financial loss to the farmer,' she said.

The nesting period for many birds like curlew, lapwing, dunlin, golden plover and skylark coincides with the lambing season — disturbance causes eggs to chill or birds to abandon their nests.

After a request from Willsworthy Conservation Group, the DNPA has asked that letter boxes are removed from the Tavy Cleave area during the lambing season of March 1 to July 15.

Letterboxers have also been asked to avoid using Steeperton Tor, Headland Warren, Cut Hill, Black Hill and Swelltor Quarries during this time.