Ponies have roamed the moors of Dartmoor and Bodmin for years and are as much a part of the moors as the heathers that grow there. But is the very survival of the Dartmoor pony, which is the symbol of the National Park, now under threat? Helen Mark is on Dartmoor to meet some of the people whose lives revolve around the ponies and who are fighting to preserve them and ultimately the moorland on which they roam.