A wildlife conservation charity has called on landowners to introduce new species into Wales' landscape.
The Wilderness Foundation said there were economic benefits to be gained from "wilding" the Welsh countryside.
Its spokesman Toby Aykroyd said: "Wales has some surprisingly large wild, areas that are bringing negligible benefit to communities and land holders."
The charity says it can advise on how best to re-establish birds of prey, beaver and even species like elk.
The Wilderness Foundation, formerly the Wildlife Trust, was established in 1974 by the explorer and philosopher, Sir Laurens van der Post.
It is part of a worldwide network of conservation bodies whose aim is encourage the public to appreciate wilderness areas, and for rural communities to protect the wild animals in their locality.
Spokesman Mr Aykroyd said "wilding" an area - re-establishing species which have disappeared, perhaps centuries earlier - can bring a long-term economic benefit from tourism and alternative livelihoods.
Six beavers have been introduced to an estate in Gloucestershire
The foundation has identified Snowdonia and the Brecon Beacons as areas where herds of wild animals could be reintroduced, bringing "nature tourism".
He said: "It's very much up to local people to decide what's appropriate for their area.
"Farmers are having a hard time of it. What were proposing is giving farmers a range of wildland or natural habitat-related activities, nature tourism being one of them."
He said the charity had received "positive feedback" on 22 schemes across Europe where beaver had been reintroduced into the wild and that the success of red kite in Wales was also an indicator of how landowners could benefit from encouraging new species.
Mr Aykroyd said the Wilderness Foundation had been in touch with a number of conservation bodies, including the Countryside Council of Wales.
On Thursday, six Eurasian beavers were released into an enclosed reserve as part of a conservation project at the Lower Mill Estate in the Cotswold Water Park in Gloucestershire.
However, the estate owners will not be allowed to release them into the wild because they are not native species.
Biologist and broadcaster Howie Watkins told the BBC the reintroduction of animals like beavers into the Welsh countryside should be done "very, very carefully".
"It's a crazy plan but it just might work given enough time. These upland areas are impoverished - it's a process our Neolithic ancestors started 4,000 years ago," he said.
"They changed them possibly forever, but there is a possibility we could make them more productive for wildlife again."
And he said it was vital that anyone planning to release non-native animals into the wild should get their "paperwork sorted" first.
Defra said that any release of a non-native species must be subject to a scientific environmental assessment and licensed under wildlife legislation.