"It's beginning to feel like the Wild West up here when it comes to sheep crime - it's soul-destroying," says farmer Colin Abel, scanning his flock high up on west Dartmoor farmland.
This winter - like most years - Mr Abel is missing more than 400 ewes.
He says in the last decade he has lost nearly £500,000 worth of livestock to sheep rustling, which is pushing some farmers to the brink of quitting or bringing their flocks off the moors.
Devon and Cornwall Police says livestock theft is challenging to police but its officers are "pursuing every line of inquiry" through "forensics, surveillance, tracking and more".
