At first glance they look like friends out for a casual hack on a blowy Exmoor morning. The only giveaway is the Avon and Somerset police badge on the back of the riders' high-visibility jackets.

This is the force's new crime-fighting initiative, Rural Community Watch, a mounted team that will provide more access to its biggest and wildest beats.

Thirty volunteers have signed up so far to patrol on horseback the lanes, bridleways, valleys and moors of Exmoor. They are trained to look out for anything suspicious and report back to the car-bound bobby, PC Nick Wood.

If a hiker gets lost or a walker is injured high on the West Country moor, they may be able to get there before a rescuer in a car or on foot and save the danger and expense of scrambling the force helicopter.

Wood said that Neighbourhood Watch worked well on Exmoor. A "horse watch" has also been set up, aimed at combatting the many thieves who target equine equipment. "This is a combination of the two," he said. "With the cuts, resources up here are a big issue and so we need to be as dynamic and imaginative as we can to cover Exmoor."

It is a huge area. Wood has 350 square miles to patrol and often does 150 "slow miles" a day along winding country lanes. The crime rate is not huge but there is a problem with burglars breaking into barns and outhouses and stealing equipment, with fly-tipping, deer poaching and, occasionally, sheep rustling. Because there are relatively few crimes, residents feel it all the more deeply when something does go wrong.

As volunteers, the participants have no more power of arrest than any other citizen. They are not allowed to follow or search and are not expected to get involved in the policing of hunting – one of the most sensitive issues in these parts.

"They are professional eyes and ears," said Wood. "They are aware of the policing priorities in the area. Anything suspicious sticks out like a sore thumb anyway and they can report that back to me. At the very least it will slow motorists down, at the most we'll be getting some great intelligence out of it."

Among the volunteers out on patrol in the village of Huish Champflower on the edge of the moor when the Guardian visited was Mary-Anne Ghazala and her mount, an ex-racehorse called Strenue, once trained by Martin Pipe.

"We do have a problem around here with people stealing things like chainsaws and quad bikes," she said. "We'll be able to spot people we don't recognise if they seem a bit suspicious and take a note. Nick will be able to look them up on one of his clever machines."

Would she like the same sort of powers as a police officer? "Good lord no," said Ghazala, a British Horse Society instructor. "This is just a way of helping the police out a bit. Most of us are hacking out anyway so we can just do our bit while we're exercising our horses."

There is a stringent process, however, before a rider can become a member of the patrol. A candidate must undergo a security check and demonstrate that they can safely walk, trot and canter both on and off-road. Horses must be "obedient, quiet, mannerly".

Once in, the riders are issued with that high-visibility jacket, a notebook and torch and are obliged to put in a certain amount of time each month. They are also expected to keep their tack – saddle and bridle – in good order and make sure their horse is "clean and tidy". They do not get paid, not even expenses, and, obviously, have to provide their own horse.

Other forces, including Hertfordshire and Norfolk, have trained special constables to patrol on horseback but Avon and Somerset have preferred to go down the volunteer route, part of its "active citizenship" campaign.

Amanda Cowley, who looks after four children, three horses and works as a book-keeper, has also – somehow – found time to become a volunteer. "I think it's important we all try to do our bit to help the police." She will be keeping a particular eye out for dodgy scrap dealers and poachers. "They tend to come out at night to poach but are around earlier in the day checking places out," she said.

Helen Goff will be patrolling on her 20-year-old thoroughbred, Sula. He thought he was going hunting today (legally, of course) but seems happy to be walking the lanes around Huish Champflower.

"I think we're be a very visible presence in these high-visibility jackets. One of the really good things is that we know the area very well. And we're high up so we can see a lot more than you see in a car."