Wildlife Trusts has said it wants to reduce the number of sheep on the estate by about two thirds from 1,500 to 500 and quadruple the number of cattle to 200.
But it also wants to introduce other species – the European bison has been extinct in the wild in Britain for more than 6,000 years but could be making a comeback.
Weighing up to 920kg (145 stone), it is one of the heaviest land animals in Europe and falls under the Dangerous Wild Animals Act.
The Wildlife Trusts’ director of landscape recovery, Dr Rob Stoneman, says while it would be “extremely unlikely” bears and wolves could be reintroduced, European bison could be a long-term prospect on the Rothbury Estate should it take over.
“It would be immensely exciting to have bison in the hills above Rothbury,” he says.
“We’ve introduced bison into Kent woodlands already really successfully, wouldn’t it be fantastic to have them in Northumberland?
“Never in high numbers, of course, because they range over quite a big area.”
However, he adds it has not yet been discussed with locals.
“If people didn’t want it to happen, we wouldn’t make it happen.”