Demands to reintroduce predators such as wolves and bears could significantly damage public support for rewilding the British countryside, a senior conservationist has said.

Francesca Osowska, chief executive of NatureScot, a government conservation agency, said rewilding could only succeed if it won support from people living in and managing the countryside, including farmers and Highland estate managers who are worried about losing their livelihoods.

She said focusing on totemic predators such as wolves risked alienating the people living in rural areas whose involvement is essential if the large-scale restoration programmes needed to address the climate and nature emergencies were to succeed.

Osowska said: “We need to think about rewilding as a much broader concept. We need to think about restoring all of nature, not just large mammals. And that goes from the pine hoverfly to ensuring that we’ve the right mix of forestry – different land types to have that mosaic of habitats.

“The vision I want is of a nature-rich future. Nature-rich means we’re all touched by and living in harmony with nature and able to benefit from it.”

“I began my walk on the Alladale Estate in Sutherland. At 28,000 acres, it comprises two valleys, Glen Alladale and Glen Mor. From the summit of the highest peak, Meall nam Fuaran, at 674m (2211ft), you can see the sea both ways. Paul Lister purchased the land in 2003. When he announced in 2007 that he intended to fence in Alladale and reintroduce two wolf packs, he generated the sort of media furore that most campaigns can only dream of. There was a  six-part BBC documentary – headlines called him the wolf man, and howling mad. But Lister is clear in his vision. “It’s carnivores that are needed to manage deer numbers,” he says. “Trees aren’t out of control in Scotland. Deer are.”

There is debate as to the extent that the forests of Caledonia once stretched. While both climatic and human factors contributed to their demise, it is deer that are preventing their return. Each tree I saw as I walked south was memorable for its scarcity, a single birch on a rocky outcrop, a clutch of rowan on an island in the river, each in some inaccessible spot where it had been protected from the nibbling.

A similar problem, caused by elk, was the reason behind the reintroduction of the wolf into Yellowstone National Park in 1995. How Wolves Change Rivers, narrated by journalist George Monbiot, was one of the more unlikely videos to go viral last year, now watched by more than 20 million people. Bringing back the wolf to Yellowstone, he claims, not only reduced elk numbers, but it kept them skittish and on the move, allowing for further regrowth of the trees.

Local MSP Robert Gibson sees people, not wolves, as “the most endangered species of all” in his constituency, as the young move south for education and employment. “This is a Clearances landscape,” he says, referring to the eviction of tenants to make way for sheep in the 18th and 19th Centuries, resulting in Scotland having one of the highest concentrations of land ownership in the world.