Where the bison roam

Meet the wild beasts restoring Blean Woods

Kent Wildlife Trust has introduced bison – last seen in the UK 12,000 years ago – to restore degraded forest in Blean Woods. It’s one of the UK’s most ambitious conservation projects. Just don’t go calling it rewilding, Weald warden Matt Hayes tells Karen Thomas

The noticeboard in the ranger’s cottage in Blean Woods is festooned with biro drawings of bison. Kent Wildlife Trust (KWT) is rolling out new, bison-themed merch – T-shirts, tote bags, cuddly toys, pens and mugs – in its giftshops. But Kent’s newest celebrities are lying low as Weald warden Matt Hayes leads our small group through the woods.

“Usually, when the press visit, they want to see bison,” says the KWT media manager. “It’s nice to show media around who understand why maybe they won’t.”

The bison are definitely around. Head bison ranger Tom Gibbs is tracking their tags on his laptop. He points out the slow-moving dots on the screen.

And as we start the tour, three young rangers return from their morning walkabout. Yes, they’ve run into the herd – three females, a bull and the one-year-old calf – on the northern edge of the enclosure below the road.

Newest of the five is the bull. He’s quite the character, say the rangers. His party trick is to hide behind trees, unaware that his flanks are bulging out on either side for all to see.

The bull – like the other bison – has no name. Wild means wild and Kent’s bison rangers have rules: no cute names, no tracking by drones, no non-essential human contact.

Blean Woods is a stretch of degraded woodland outside Canterbury in Kent. It’s not obvious bison territory. Blean is Old English for rough ground. At more than 1,200 ha, Blean is one of England’s largest ancient forests and, until the 20th century, most of it was church land.

Kent bison: a working herd

Sessile oak, hazel, beach, oak and willow once thrived on Blean’s acidic clay, but the woodland has been overmanaged for centuries. During the 18th century, Kent hop makers replaced the original species with sweet chestnuts to make planting frames. When hop farming collapsed, foresters planted fast-growing conifers for timber.

The timber plantations have turned a natural woodland into close-packed regiments of pine trees, the ground beneath drained and lifeless; no understory, few fungi – a woodland wasteland.

“The forest has changed massively,” Hayes says. “About a third is conifers, about a third is sweet-chestnut monoculture and the rest is a mix of oak and broadleaf forest. Since Kent Wildlife Trust bought Blean from a merchant bank 20 years ago, we’ve set about trying to change that.

“We need to change the structure – get rid of the conifers and break up the dominant sweet chestnuts. We’re coppicing to create new structures and return variety to the forest. And we’ll take what we learn from the animals’ different grazing patterns and scale it up.”

Which is where the bison come in. As they push through forests, bison break branches and fell trees, letting daylight reach the forest floor. They take dust baths that clear the ground for reptiles and burrowing insects. Their thick fur traps, transports and sheds seeds. Birds gather shed fur to line their nests.

Scientists think that the UK lost its forest bison at the end of the last ice age. These European bison are distant cousins, but will play the same role at Blean as their ancient forebears.

KWT’s Wilder Blean project released the three female bison into West Blean in summer 2022. One was pregnant; her calf made a surprise appearance in the autumn. The bull arrived from Germany last December.

The bison are Blean’s star turn, but since March, they’ve had a support act: three female Iron Age pigs, six male Exmoor ponies and four longhorn cattle. Between them, the animals are managing a woodland 11 times the size of the Vatican, grazing and turning the earth to help new plants to establish. Their dung will feed invertebrates and fungi to support a more natural ecosystem.

The four longhorns – a bull and three cows – have their own territory. They play a similar role to the bison, clearing woodland, grazing and creating the deadwood that fungi and invertebrates love. The ponies graze vegetation back to ground level, rather than uprooting plants wholescale as pigs do.

The pigs are a cross between wild boar and domesticated Tamworth pigs. They turn the ground, breaking up dense soil and clearing bracken so that seeds can germinate. “We couldn’t bring wild boar, because of dangerous wild animals legislation,” Hayes says. “That would have been the wildest option, but you can’t put them anywhere people will be.”

The rangers will set baselines to monitor and measure how the animals regenerate the woodland and how this boosts biodiversity and carbon capture. They will compare the bison-grazed areas, the cattle-grazed areas and areas that are forested and share the findings with partners including the RSPB, the Woodland Trust, Kent County Council, the Forestry Commission and Kentish Stour.

The carbon-monitoring work is KWT’s biggest such programme to date. It’s early days for UK carbon offsetting, but KWT and its parent, the Wildlife Trusts, are working to develop Wilder Carbon credits (see The Environment December 2022).

Wilder forest management

Wilder Blean fuses many strands. It aims to restore nature, capture carbon and boost Kent leisure and tourism. However, delivering all of that is tricky to balance.

Covid-19 reconnected so many of us with nature, but the more we love the great outdoors, the more pressure we put on green spaces. And rewilding stirs up strong passions.

When Scotland reintroduced sea eagles, sound and fury on social media pitted hill farmers and pet owners against conservationists. Perhaps this is why Hayes wants to avoid the label. “This project uses a wilding approach,” he says. “We don’t say rewilding – we’re just trying to get Blean Woods wild… Climate change and biodiversity loss mean we can never rewild completely, in any case.

“Often, conservation tries to maintain things as they existed at a specific point in time. This project isn’t about going back in time to some set point, way back in history. We want to return Blean to a more natural state – a mosaic of mixed broadleaf trees. We want the forest to be whatever it wants to be – no more planting, letting natural processes do the work.”

So KWT must work with local people, too, to build support for Wilder Blean – to invite interest, but not so much that it disturbs the animals. Blean draws dog walkers, horse riders, runners, day trippers, foragers and cyclists. If you go down to the woods today, you’re in for a big surprise: it’s busy.

At the time of writing, the trust was raising money to buy and install bison bridges. These overpasses have viewing sections to let people watch the animals pass through a tunnel below without disturbing them.

Success for Wilder Blean will mean more biodiversity, more carbon capture, more connected nature corridors and more green spaces for people.

“It’s about getting more nature – but it’s also about enthusing people, about getting them to think,” Hayes concludes. “We’ve visited and learned from bison-restoration projects in the Netherlands, but we’ll also be learning as we go. In turn, we hope people will come and learn from us.

“We are so disconnected from nature. People like the pine trees – they think these are real, natural woods, that this is what forests are like. But the plantations are almost as far removed from natural woodland as a high street. Most people don’t think about little things like seed dispersal. We need to spread that message, to reconnect people to nature.”

This story is published in the December 2023 / January 2024 issue of The Environment magazine