The last lynx in Britain died over 1,000 years ago, victims of deforestation and a rampant fur trade.

But the long-eared wildcat could make a comeback in 2016 as part of an ambitious “rewilding” experiment.

A group of conservationists and scientists plan to release six Eurasian lynx at selected woodland sites around the country, believing the cats can revive ecosystems which have suffered in their absence.

“The lynx is absolutely perfect for the UK,” says Paul O’Donoghue, chief scientific adviser of Lynx UK. “The countryside is effectively dying with no forest regrowth and lynx will drive regeneration.”

Without predators, the deer population has grown unchecked. Overgrazing has decimated forest flora, and the loss of habitat also threatens rare birds and mammals.

Lynx naturally prey on deer, and it is hoped they will engineer a “trophic cascade” – the effect of introducing a predator to limit the species below them in the food chain, allowing the species below them to recover, and restore natural balance to the ecosystem.

Lynx UK also hopes the charismatic new arrival will spark public passion for conservation and eco-tourism, as it has in Germany.

“The Lynx is a magnificent animal with the power to inspire and captivate like no other UK species,” says O’Donoghue. “We feel it can be a flagship species for UK conservation.”

An independent cost-benefit analysis estimates that lynx could generate around £70 million ($105m) over 25 years through tourism and reducing the damage caused by deer.

The scheme has public support – one survey showed over 90% in favor – although farmers have expressed fears that livestock will become prey. Lynx UK say such attacks will be rare, based on data from similar programs in Europe.

For the initial five-year trial, lynx will be fitted with GPS trackers to monitor their movement, predation and breeding patterns. Should the trial prove successful, it will be extended and expanded.

Ecology of fear?

Across the world, conservationists are looking to lost predators to solve ecological crises, with campaigns to restore tigers to South China, grizzly bears to Washington State, and wolves to Scotland.

Much of the enthusiasm traces back to the seminal case of Yellowstone National Park.

Following the reintroduction of gray wolves to the Park in 1995, studies showed a striking recovery of plant species such as aspen and willow trees. The healthier habitat supported the return of animals, and even improved the flow of rivers by strengthening their banks.

Researchers concluded the predators were having dramatic effects, not only by killing elk that overgrazed plant species, but also by changing their behavior.

The “ecology of fear” was coined to describe the adaptation of prey to a new predator, and consequent benefits to the ecosystem. Proponents claimed that elk were avoiding areas perceived as dangerous, sparing plant life, and maintaining alertness that reduced their consumption.

But subsequent studies challenged the theory, showing that elk were still eating plant species in high-risk areas, and were not learning to anticipate attacks – particularly as wolves are roaming, unpredictable predators.

Predators are not a quick fix for long-term decline, argues Dr. Tom Hobbs of Colorado State University, an ecologist who has extensively studied re-introduction programs, including at Yellowstone.

“The removal of predators for decades causes changes in a system that make it resistant to the effects of reintroduction,” the ecologist says. He cites the loss of beavers at Yellowstone as a major obstacle to the recovery of plant life.

Hobbs acknowledges the value of predators to ecosystems, but is skeptical about the “ecology of fear” theory and believes rewilding efforts should focus on proven effects.

“Introduce a large, capable predator into an area and they will substantially reduce the numbers of prey – that’s the reason we are beginning to see recovery (in Yellowstone),” he says. “It’s a very clear mechanism to reduce grazing pressure and it has great merit. I don’t think it’s necessary to dress up behavioral effects.”

Building from the ground up

Rewilding Europe is dedicated to restoring natural function to ecosystems across the continent, aiming to establish one million wild hectares by 2022.

Reintroducing predators is a small part of the mission, says Managing Director Frans Schepers, who has enjoyed success building from the ground up. He points to the 1980s development of river landscapes in the Netherlands as a model of effective regeneration.

“Widening flood plains and removing dykes allowed river nature, including alluvial forests, to return, and the introduction of beavers,” says Schepers. “We built up a lot of experience that became an example for other parts of the world.”

The methods were adopted for rivers around the world, including the Rhine, Danube and Yangtze.

Rewilding Europe has the same bottom-up approach to participation, building a network of grassroots campaign groups across the continent with projects from re-introducing bison to Germany to building an oasis in southern Italy.

“We want to connect all the initiatives to learn from each other and share experiences”, says Schepers. “There are common principles but no blueprint – you have to look at local context. What works in the UK might not work in Romania.”

Progress depends on inspiring enthusiasm and an entrepreneurial spirit among local partners.

“It’s important this is demand driven rather than imposed on people,” the director says. “We try to find early adopters to work with…and start doing things on the ground.”

When projects do not have public support, Schepers notes, it can prove fatal for returning species - particularly predators.

Coexistence from a distance

As rewilding programs expand, the greatest challenge may be finding space that will be left untouched.

“Natural processes require sufficiently large areas to allow for dynamic changes to develop over time and space…this may represent a constraint,” says Enrico Brivio, spokesman of the European Commission, which funds several rewilding programs.

Brivio adds that protection for such areas requires “the exclusion or reduction of human interference.”

Author George Monbiot, a leading advocate of rewilding, also supports the creation of protected zones. But ultimately he hopes to rewild humans too.

Monbiot has argued that people can suffer from “nature deficit disorder” – without a connection to the wild world, we are more prone to mental and physical health problems from depression to obesity.

“My hope is that when we manage to restore magnificent ecosystems on our doorsteps, people exploring them will begin to discover aspects of themselves they never suspected they possessed,” says Monbiot.

“Thrilling encounters with wildlife and wild places (can) open your mind, expand your imagination, and show you ways out of anxieties and fears.”

The rewilding movement is now entering a critical phase, in which bold experiments will face increasing exposure and proximity to human populations.

The coming years could decide whether human civilization and wild nature can truly coexist.