WILD boar living in the Forest of Dean could spread to neighbouring regions, such as Monmouthshire, by swimming across major rivers according to an expert.

Dr John Dutton, from the University of Worcester, was speaking to BBC Radio Gloucestershire about the UK's largest population of wild boar.

He said that the animals would be able to cross rivers such the Severn if they wanted to.

Dr Dutton believes one route the animals could take would involve the River Severn, Britain's fastest flowing and longest river.

Wild boar a can weigh up to 220lbs and reach nearly three feet in height.

The animals have been known to become territorial and confrontational if provoked.

Dr Dutton said that, if left unchecked, "they could reoccupy the whole country".

Although he admitted this would take some time.

"But the River Severn, certainly north of Gloucester, would not stop them crossing if they felt like it," he said.

The British Association for Shooting and Conservation (BASC) have said that an "action plan" is needed to mitigate the spread of the animals to other areas.

The group have highlighted "the role shooting plays in Wales’ environment" and have called for the production of a five-year Feral Wild Boar Management Action Plan for Wales.

BASC Wales director Steve Griffiths said: “There is a growing concern over the expanding wild boar population in the Forest of Dean and some wild boar releases in South Wales, too. "Apart from the extensive damage to road verges, village greens, gardens and football pitches for example, they contribute to an increased number of road traffic accidents, which can be fatal.”

“What is needed in Wales is an action plan that will enable us to get in control of the population, further our understanding of their ecology and benefit from the sale of wild boar meat."