Three years on from the ‘knitting together’ of 3,400 hectares of priority habitat to create the UK’s first-ever ‘super’ National Nature Reserve (NNR) on the Purbeck Heaths in Dorset, the National Trust is working with reserve partners on an ambitious project to create a 1,370-hectare open ‘savannah’ for free-ranging, grazing animals as it would have been thousands of years ago.
The Purbeck Heaths super reserve is a rich mosaic of lowland wet and dry heath, valley mires, acid grassland and woodland, along with coastal sand dunes, lakes and saltmarsh.
Already one of the most biodiverse places in the UK it is home to thousands of species of wildlife, including all six native reptiles.
With ambitions to make the area even more nature-rich, the National Trust, RSPB, Natural England and Dorset Area of Outstanding Natural Beauty) have created an open grazing site across half of the super NNR where ponies, pigs and cattle will roam freely to graze alongside deer to help shape a more diverse landscape with richer habitats.
Here they can browse and turn over the soil in ways that are already benefiting wildlife from birds such as nightjars to tiny plants such as yellow centaury, while the fence removal has made the area even more accessible to people.
David Brown, National Trust lead ecologist for Purbeck said: “Over large swathes of open grassland and heath, these domestic grazers are now mimicking their wild ancestors, who would have shaped habitats in the past.
“We can’t bring back aurochs, the native ancestors of our domestic cattle, but we can use our 200 Red Devon cattle to graze and behave in equivalent ways.
“Similarly, Exmoor ponies mimic the actions of now-extinct tarpan horses, and the quirky, curly coated Mangalitsa pigs are rooting around like wild boars.
“We’re also discovering that by letting them get on with their own thing as much as possible, our grazing animals explore new habitats and discover different types of vegetation to eat – all of which help create a more dynamic and complex ecosystem.”
In a natural environment, large herbivores also play a crucial role in helping plants and less mobile insect species move around the landscape – carrying seeds and larvae on their fur and hooves, or in their dung.
By giving cattle, ponies and pigs this huge landscape to wander around, they are helping rare and threatened species such as Purbeck mason wasps, and heath bee-flies disperse and build stronger populations.
David said: “Grazing in their own individual ways, these animals are slowly forming diverse, wildlife friendly habitats.
“Cattle are untidy eaters, leaving messy tussocks perfect for insects; pigs turn over the soil and help sand lizards burrow; and ponies nibble tightly down to the ground creating grassland lawns full of specialist flowers such as storksbill and waxcap fungi.
“These grasslands can be really important for pollinating insects too, including rare mining bees.
“It’s the perfect mix of habitats in which biodiversity can thrive, and a great landscape for people to also roam freely.”
Tom Munro, Dorset AONB Manager said: “As well as making the landscape richer for nature, some of these grazing animals will provide good quality food and support the local economy through ecotourism, such as camping and safaris.
“The Purbeck Heaths partners have also brought together local businesses, community groups, parish councils and schools to create a sustainable tourism plan – to manage the impact of visitors on nature and also increase the value of the landscape to local people and the economy.”
Successes of the ‘Super’ NNR
In 2022, Studland Heath saw the highest numbers of silver-studded blue butterflies recorded in 45 years of monitoring; on one of the monitoring transects their numbers increased from 111 in 2011 to 1317 a decade later.
And, at RSPB Arne alone, Dartford warblers have increased from just two breeding pairs in 1965, when there were less than 10 pairs nationally, to 92 pairs in 2022 – and over the whole super NNR there are now thought to be about 300.
Rare plants are also thriving in greater numbers including marsh gentians, great sundews and pale dog violets and yellow centaury.
Last year, ospreys bred on the edge of the NNR for the first time in 200 years – following a reintroduction project that began in 2017 by local charity Birds of Poole Harbour.
The UK’s largest native bird, the white-tailed eagle is also now regularly seen flying over the reserve, following its introduction to the Isle of Wight.
Another positive outcome is that through the super NNR being bigger and better connected, the landscape is now more resilient to fire.
Last August a disposable barbecue set fire to Studland heath and devastated an area of about 5 hectares – but because the site is now nestled within 3,500 hectares of heathland, wildlife is already recolonising from all sides.
The fire has had a much smaller impact than if it had been a small, isolated nature reserve.
The super NNR will also be the base for the BBC’s forthcoming series of Springwatch with the first live show on Monday 29 May with viewers able to enjoy this spectacular landscape from their sofas and find out more about the wildlife that lives there.