Herds of bison roaming the countryside is a sight more accustomed to the great plains of North America than the green fields of England.

But one North Yorkshire family have changed all that by bringing a number of the animals to graze the ancient parklands surrounding their home.

Roger and Julia Clutterbuck of Hornby Castle, near Bedale, now have a herd of seven bison - six cows and a bull.

The plan is use them as breeding stock and market the meat of their offspring under the Hornby Castle brand.

They are planning to set up their own shop and also sell the meat to local restaurants, several of which are keen to offer it on their menus.

There are less than 150 North American bison in the UK. The new arrivals have come to the estate from Wiltshire. Mr Clutterbuck had hoped to get the animals from Canada, but the discovery of BSE in the country led to exports being banned.

They have joined the estate's deer herd and are grazing in their own special enclosure, allowing walkers and riders to view them.

Mr Clutterbuck said: "They are gentle giants, but they have a tendency to be single minded - a full-grown one weighs almost one tonne and you can't tell them where to go.

"However they are remarkable because they will not cross a line, whether it's a single strand of wire or a railway line." He said the key to producing high quality meat was to keep the bison happy.

"If the raw meat is a very red, translucent colour, that is the colour of a happy bison," he said. "If you have an unhappy or stressed bison, unfortunately what you then get is a brown, grey meat.

"Bison meat is the most heart-friendly meat you can buy, with the lowest cholesterol level and very little fat."

The Clutterbucks, who received a grant from Defra's Rural Enterprise Scheme for the venture, are planning to use the income generated from the bison to help restore the parkland around the castle.

Old stock fences are being removed and arable land returned to grass to create a 550-acre expanse of parkland.