By Lauren Beavis & Rom Preston-Ellis & Anita Merritt A petition has been launched to save the famous Dartmoor ponies – which campaigners claim are at risk of ”extinction”. Nearly 100,000 signatures are calling on the government to halt the decline in the number of ponies that have freely roamed for centuries. Figures show 20 years ago there were 7,000 Dartmoor Hill ponies roaming free on Dartmoor in Devon – today there are only 1,000. Natural England has introduced new rules on the moorland – which mean farmers will now have to pay for grazing the ponies on common land. But a petition launch…