How rewilding could turn Britain into a modern day Jurassic Park: Scientists want to reintroduce wolves and bears to the UK - but critics warn it could be 'catastrophic'

For many Brits, the idea of coming face-to-face with a wolf during a lovely woodland walk sounds unthinkable. 

But according to scientists, this particular 'rewilding' scheme could become a reality. 

British academics and land owners have proposed bring wolves, bears and even lynxes back to the British wild – as they used to roam here before dying out. 

But some are concerned that they could wreak havoc on flocks of sheep or even eat our pets – with one calling it a potential 'catastrophe' in the making. 

Wolves and bears are already in Britain – albeit in a zoo-style enclosure that's open to the public. 

At Bristol Zoo Project, run by the Bristol Zoological Society, the two species live in the same habitat together.

However, wolves and bears are not known to be roaming the British wild as yet – and some experts hope it stays that way. 

Andrew Connon, president of National Farmers' Union (NFU) for Scotland, called it an 'unacceptable' idea, following proposals the Highlands could be a home for them.

'NFU Scotland remains crystal clear that any proposals to re-introduce predators such as lynx, wolves or bears are wholly unacceptable to Scottish farmers and crofters,' he told MailOnline. 

Ian Convery, a professor of environment and society at the University of Cumbria, said wolves and bears would have to be 'translocated' from another country where they still thrive.

But one of the main considerations for authorities approving any such move is whether there's public acceptance for the translocation. 

'Public acceptance is likely to differ significantly across different sectors, and in general, those most likely to be affected by the translocation need to be listened to carefully,' Professor Convery told MailOnline. 

'The ecological case for wolves in Scotland is fairly clear, there is good habitat, good prey availability, and they would likely persist if translocated, but the social and political case is much more complex.' 

Dominick Spracklen, professor of biosphere and atmosphere interactions at the University of Leeds, said wolf reintroductions 'might never be feasible in the UK'. 

'Many people, particularly farmers, would not currently support a wolf reintroduction,' he told MailOnline.

'Wolves would prey on sheep and other livestock so farmers are right to be concerned; conflict between farmers and wolves remains a big issue across Europe.' 

However, there could be some benefits, he added; for example, wolves could potentially reduce the number of road traffic accidents involving red deer. 

Those in favour of the idea often point out that Britain used to be home to these creatures.  

The grey wolf (Canis lupus) roamed Britain from the inter-glacial times (roughly 50,000 years ago) to the middle of the 18th century before being hunted to extinction, while the brown bear (Ursus arctos), also once a common top predator in Britain, died out here an estimated 1,000 years ago. 

Proposals to reintroduce the grey wolf to the Scottish Highlands and English countryside date back more than quarter of a century. In 1999, Dr Martyn Gorman, a senior lecturer in zoology at Aberdeen University, said the canines could be helpful curbing red deer populations across Britain. 

Red deer consume tree saplings and bark from older trees, which prevents the growth of native woodland – so wolves could hunt them to keep deer numbers down. 

In the coming years, the idea of bringing wolves and other predators such as bears and lynxes to the UK received further backing from other figures – including Paul van Vlissingen, a wealthy Dutch landowner based in Scotland. 

In 2007, Imperial College London scientists said wolves could aid efforts to reforest the Scottish Highlands and increase bird biodiversity in the region. 

Then just over a decade ago, entrepreneur Paul Lister made headlines by announcing plans to release both species to Alladale, his 23,000-acre reserve northwest of Inverness. 

The multi-millionaire was inspired by Yellowstone National Park in Wyoming, which had an ecological rebirth after wolves were reintroduced in the mid-1990s. 

'The big vision is to have a minimum area of 50,000 acres, have a fence around it, and bring back wolves and bears into that area,' he told the BBC.   

However, a spokesperson for Alladale has said it no longer plans to introduce wolves or bears – although they would not confirm when or why the idea was scrapped. 

Alladale is still supporting a project working to return lynx to Scotland, the spokesperson confirmed. 

Bears, wolves and lynx are still spread across mainland Europe in countries where they were not driven to extinction – including Sweden, Germany and Spain. 

In rare cases, grey wolves have been known to attack humans, but they are not typically dangerous, according to wildlife charities. According to an EU analysis, there has not been a verified fatal wolf attack on humans in Europe in the last 40 years. 

Even if people are scared of wolves, they pose 'almost no threat to humans', Professor Spracklen said. 

'Documented cases of wolf attacks on humans in Europe are extremely rare (and when they have occurred have almost always been linked to rabies in Europe),' he told MailOnline.

The brown bear, which can be 6-7 feet tall when on hind legs, is generally less aggressive than the North American grizzly bear, but attacks can still happen. 

Human deaths following attacks by brown bears have been reported from Romania, Slovenia, Bosnia & Herzegovina, Croatia and Finland, according to the Wolves and Humans Foundation. 

Likewise, lynx typically ignore humans – but farmers are concerned because they are big enough to kill sheep much like wolves and bears are. 

Last month, Scotland’s First Minister John Swinney said the reintroduction of lynx, or any other carnivorous species such as wolves, would not take place under his government. 

However, the spokesperson for Alladale said the Minister's comments 'were not an official government ruling'. 

'We have signed an open letter to the First Minister sent by Steve Micklewright of Trees for Life, calling for him to retract his comments on the basis of evidence-based strong public support for Lynx reintroductions,' they said. 

In response to the idea, a spokesperson for The Wildlife Trusts said any such reintroduction 'must be carefully consulted on' with the public. 

'With 15 per cent of our species threatened with extinction, and 41 per cent suffering serious declines since the 1970s, the UK has the unenviable tag as the one of the most nature depleted countries in the world,' said Rob Stoneman, director of landscape recovery at The Wildlife Trusts. 

'Bringing back lost species is crucial if we are to reverse this catastrophic nature loss. However, any reintroduction must be carefully consulted on and planned with the people who will be directly impacted. 

'For example, one of the reasons that the River Otter Beaver Trial was such a success, and part of the reason wild releases of beavers are now legal in England, is because the animals had such overwhelming support from local people.' 

Brian Zimmerman, director of conservation and science at Bristol Zoological Society, which is keeping wolves, bears, lynxes and wolverines in enclosures at Bristol Zoo Project, told MailOnline: 'Our bears and wolves were all zoo born animals but they are by no means ‘tame’ and still considered wild animals.

'We encourage natural behaviours by having them in a natural setting, similar to the wild habitat that allows them to forage and explore the woodland as they would in the wild.

'In terms of danger to humans – any wild animal can be dangerous and there are well documented cases of both species having negative interactions with humans, usually as a result of human encroachment on their habitat. 

'However, most wild animals do prefer to avoid humans as they are afraid of them.'