Across the River Wolf and along several miles of muddy Devon lanes lies Derek Gow’s lair. Inside a crepuscular barn filled with a pungent aroma, an imposing, bearded Scot sits surrounded by his collection of animal skulls, stuffed beavers, taxidermied badgers and birds of prey. A distinctive stench wafts from the head of an ibex mounted on the wall. The barn is badged as an education centre but it would terrify some visitors.

This gothic scene reaches its climax when – bang! – a shot is fired nearby. Gow looks relaxed. “She’s not shooting anything,” he says of his neighbouring farmer. “It’s a gas gun, trying to scare a bunch of complacent geese.”

Gow, a former sheep farmer, has become one of the most remarkable figures in British conservation. After working in various zoos, he began captive-breeding water voles 25 years ago. Since then, working with conservation groups and landowners, he’s repopulated wetlands with 25,000 of the highly endangered mammal. The “vole room” on his rewilded farm still produces 1,000 each year.

Alongside voles, he started breeding beavers for fenced rewilding projects across Britain. A number escaped and now form a burgeoning population living freely along the 60-mile River Tamar between Devon and Cornwall. Over the past 15 years, other beavers mysteriously materialised on river systems across the country; Gow denies it was his work but beavers are officially recognised as a native species once again. After writing a popular book about bringing back the beaver, this former lover of sheep is following it with a book about the sheep’s mortal enemy, and the most controversial candidate for returning to Britain: the wolf.

At rewilding conferences, meek conservationists will say to Gow, “We’re not here to talk about the wolf.” “Why?” he asks now. “The opponents of rewilding hate you anyway. You’re never going to convince these people.”

The wolfman of Devon: Derek Gow in his barn, surrounded by his extensive collection of skulls and stuffed animals. Photograph: Leon Foggitt/The Observer

He wants to start a conversation about bringing back the wolf, and not just because this much-traduced carnivore has loped back into western Europe and is thriving in densely populated countries including the Netherlands, Belgium and Germany which, like us, are burdened by a long history of beastly folklore. “The big predators were the things we went for first,” he says. “It’s not very mature to view every animal from the badger up as a major threat, and the only solution is to destroy them. We can never come to terms with nature, with other life on this planet, if we can’t come to terms with big predators.”

Before we discuss Gow’s hunt for the wolf in British history, where he knits together myths, dusty historical records and modern ecology to show that wolves are more deeply embedded in our landscape than we imagine, he takes me on a tour of the 400-acre farm he is returning to nature.

We speed off in Gow’s little all-terrain vehicle, slaloming through the sodden fields, wheels spinning, mud splattering, no seat belts, up steep-sided hills that until a few years ago were a familiar English patchwork of green fields. Gow is creating a new kind of idyll. He identifies his acres by field hue. The emerald pastures straight from a picture book of the countryside are the heavily fertilised “improved” fields of his neighbours. These look neat but are mostly lifeless, usually containing a single species of grass upon which cows or sheep feed. The yellow, raggedy fields are his. They appear scruffy at this time of year but by summer will be bursting with yellow rattle, knapweeds and other wildflowers.

Neighbouring farmers bemoan the tangle of Gow’s untrimmed hedges. He has messed up his land further by dumping piles of broken-up concrete and pyres of dead branches in once-lush pastures. The branches are perches for wild birds whose droppings will seed more trees; the concrete piles will attract wheatears in winter and adders in summer. He’s dug 100 ponds and channels to boost declining birds such as woodcock and snipe; the beavers will do the rest, damming small streams to expand these new wetlands. Scientific studies have shown that once this watery habitat returns, so do insects, amphibians, reptiles and birds, in their thousands.

“It’s not changing the world. It’s not the Serengeti but slowly, slowly we’re starting to see things responding,” says Gow. “Small red damselflies have gone from 40 to 670 in three years. Kestrels and barn owls come back. This year, the first crane flew over. We had goshawks last week and a nightjar calling last summer. There are charms of goldfinch in the hundreds. I never thought this farm would become a bird-watching location.”

Gow’s rewilding is funded by his environmental consultancy (he’s currently relocating water voles for Sizewell nuclear power station) and backers including environmentalist and financier Ben Goldsmith. “A gentle, kind, able man”, says Gow. “The day will come when some of the things that he’s done can be talked about and he’s just been astounding.” Gow hopes to expand his own efforts by linking like-minded small landowners and investors. Pension-fund managers visited his farm the previous day. “We want to buy as much of the river corridor as possible, to safeguard the beavers on the river system,” he says. Gow’s neighbours wonder about lost food production but he insists that this land was boggy moorland until it was drained in the 1940s, and has subsequently only ever produced relatively small amounts of lamb, beef or milk.

Gow knows that his personal rewilding is a fragment within one of the most nature-depleted countries on the planet. His major contribution to rewilding Britain is through captive-breeding “at scale”. Aged 58, he is a man in a hurry. “I want to focus on species that need a hand,” he says. He’s still churning out water voles but this year will captive-breed adders to help connect increasingly isolated wild populations of this rapidly declining snake. He’s also breeding turtle doves, white and black storks and glowworms, and plans to start on mole crickets and other bird species. “We’ll have a little shot at red-backed shrike later this year. We also want to try breeding black grouse here.”

Gow, who is famously rude about both conservationists and farmers, criticises conservation scientists for their caution over reintroducing species. “You look at the environmentalists who die year on year in the Amazon in fights with ranchers and you look where we are and we’re so fucking useless,” he says. He may secretly admire farmers for getting on and doing stuff but he thinks too many farmers only reflect on the fact that their agricultural systems have destroyed nature when they reach retirement. “Many of these old men become contemplative at the end of their lives and by the time you get to your early 70s – it’s too late. I’ve no intention of getting to the age of reflection and saying, ‘I wish I’d done that 10 years ago’. Even if I fucking fail, I’m going to do it.”

The conservation “inertia” he criticises is derived, he believes, from a terror of making mistakes. “When we began with water voles we must’ve spent six years killing water voles in different ways, and then we got it right, and learned how to breed them,” he says. “There’s no such thing as mistakes, it’s just learning. It becomes a mistake when you continue fucking it up in the same sort of way.”

Gow is aiming to produce 30 wildcat kittens per year for a reintroduction still under consultation in Devon and Cornwall. Years of controversy over bringing back predators as unthreatening to human interests as wildcats have taught him that returning the wolf to Britain is fraught with difficulty. Wolves are destined to be pawns in a culture war that pits country against town. “Speak to people in London and everyone agrees it will be brilliant. Go to a meeting here…” Gow gives a dark look.

He’s still bristling about a recent meeting in the Cairngorms about beavers and wildcat releases in the national park. A parade of “bullying bastard” farmers arrived in “a wee convoy” of tractors to protest “on the basis of the national park releasing four beavers and 18 wildcat kittens, and the farmers say they are being disenfranchised, they are the indigenous people, they produce food, and they jump up and down and scream. And then the national park authorities who are not robust people just cave in, and before you know where you are even small things become impossible. You wouldn’t speak to a Norman overlord like that,” he says of the farmers’ complaints. “Or if you did, you’d only do so once.”

Gow’s knowledge of Norman overlords comes from researching the wolf’s traumatic British history. He was inspired by his mum telling him stories of “the last wolf” in Scotland when he was a child and by rearing two wolves in his zookeeper days. Gow, who has the open mind of an autodidact, began examining all the myths of the heroic slaughter of “last” wolves which, in parts of Scotland, were passed down generations in oral culture. “The point is to tell a story that is as funny as it can be when it comes to flaying and evisceration, which is not that funny, but also to tell a story that has a degree of warmth to it,” he says.

He pieced together legends from random witchcraft books serendipitously discovered in secondhand bookshops and cross-checked tall tales with academic histories and modern ecological knowledge. Gow believes the wolf clung on in Scotland until the late 18th century and, given that young satellite-tagged wolves have been found to wander 1,250 miles in modern-day Europe, youngsters would have repeatedly entered England.

For the English, wolves were “a symbol of something that was wild, subhuman, wrong, evil” that lived further north, says Gow. They were hated because in wars and plagues they would excavate graves and devour human carcasses. Gow knows from rearing wolves that they are dangerous animals but there are vanishingly few recorded incidents of wolves attacking people in modern western Europe. Wolves are a scapegoat. Were historic yarns of women and children being killed by wolves that era’s cover for male domestic violence? “It’s impossible to prove but it might be that,” says Gow. Ultimately, we exterminated wolves not because they imperilled us but because they ate into our wealth: wolves killed sheep, and wool made medieval Britain rich. “Sheep are wolves’ oldest enemy,” he says.

Ecologists calculate that Scotland has space for 50 to 94 wolf packs. Wolves, argues Gow, will produce many environmental benefits, chiefly reducing our 2m deer, a wild population growing by 10% each year and living at a far higher density than in any other European country. So many deer are decimating rare plants and preventing the natural regeneration of trees. But the main obstacle to the wolf’s return remains sheep.

Gow subscribes to the rewilders’ view exemplified by George Monbiot that sheep are ecological vandals responsible for the nature-denuded state of upland Britain. In North America, says Gow, national parks have wild animals such as bears as their symbols; the Yorkshire Dales national park’s is a Swaledale sheep. “Is that just the British sitting with their heads up their arse and not thinking how deeply inadequate it is?” asks Gow. “Landscapes with high densities of sheep have many fewer insects; there is erosion, vegetation loss, flooding and pollution.”

Wool wealth is no more and Gow says sheep farming is a failing industry and the “food security” argument is fatuous given more than a quarter of British lamb is exported. And yet subsidies continue to support it. “Just chucking a load of money at some sheep farmer on the top of Bodmin only prolongs the misery, and the mental-health issues (for struggling farmers) and the environmental destruction.”

“Just chucking a load of money at some sheep farmer on the top of Bodmin only prolongs the misery”: Derek Gow. Photograph: Leon Foggitt/The Observer

There seems to be something viscerally personal about Gow’s dislike of sheep today, given his long history tending to them. His son manages a flock of sheep, and a few still roam Gow’s farm “left over from my mother who used to show Shetland sheep. She died in 2006. Would she have wanted me to keep them? I don’t really think she’d be bothered. I don’t enjoy them any more. It’s the end. But it’s been a long and lingering love affair. I understand why people feel about them the way they do. It’s a very vulnerable animal and you’ve got Lambing Live and Countryfile ogling over a domestic animal that’s going to be a bundle of meat in six months’ time. There’s an old saying: sheep spend their whole life being afraid of the wolf only to be eaten by the shepherd.”

French shepherds are in uproar over that country’s resurgent wolf population because 12,000 livestock animals – mostly sheep – are predated each year. Gow points out that 15,000 sheep were killed by out-of-control dogs in Britain in 2016. He hopes high-tech solutions such as a sheep collar that emits a wolf pheromone which has been shown to keep sheep safe in Switzerland might lead to coexistence between farmers and wolves.

Ultimately, he thinks, the wolf will only be allowed back into Britain when future generations take charge. “We’ll have a different cultural landscape which will enable them to do this. But we should start to talk about it. If wolves are hunting roe deer on housing estates in Belgium, why not here? We live in a time where we’ve got an urban population being enthralled when they see a wolf. Is acceptance coming with it? When there was still a late-medieval mindset, 150 years ago, nobody would have accepted any of this. So we are in a different place. Therein lies hope. But it’s through a glass darkly.”

Hunt for the Shadow Wolf by Derek Gow (Chelsea Green, £20) is out now. Buy it for £17.60 at