Wolves Could Return to Scotland and Restore Native Woodlands

Wolves once vanished from the Scottish Highlands

For centuries, no wolf howl has echoed through the Scottish Highlands. Now, a research team argues that these long-vilified predators should be restored to the landscape.

Their simulations indicate that bringing wolves back could help native woodlands return to Scotland while drawing carbon out of the atmosphere.

Human hunting completely eliminated wolves (Canis lupus) from Scotland. Tradition holds that the final wolf was killed roughly 250 years ago, although local myths and legends make the precise date difficult to establish.

At about the same time, the Jacobite rebellion of 1745 brought sweeping changes to land use across much of the country. Forests were cleared and extensive shooting estates were created.

Removing this apex predator disrupted woodland ecosystems as a whole, allowing its prey, red deer (Cervus elaphus), to increase without restraint.

Current estimates put Scotland's red deer population at as many as 400,000. The animals trample and browse on young tree saplings which, without that pressure, could develop into woodland. Native woods now cover under 4 percent of Scotland's land area, among the lowest proportions in Europe.

This is a classic example of a predator acting as a 'keystone' species: the brick in an arch that keeps the wider structure standing. Wolf reintroductions have succeeded in several nationally managed ecosystems in the US, most notably Yellowstone National Park.

In principle, restoring wolves to Scotland's wild areas would lower deer numbers and give woodland an opportunity to recover.

"There is an increasing acknowledgment that the climate and biodiversity crises cannot be managed in isolation," says lead author and environmental scientist Dominick Spracklen from the University of Leeds.

"We need to look at the potential role of natural processes such as the reintroduction of species to recover our degraded ecosystems and these in turn can deliver co-benefits for climate and nature recovery."

Wolf reintroduction, deer populations and woodland recovery

The researchers' modelling suggests that reintroducing wolves in four important Scottish areas could support a population of around 167 wolves. Within as little as two decades, that number could reduce deer density in those locations to only four per square kilometre (0.4 square mile).

They calculate that each wolf could enable enough woodland recovery to absorb 6,080 metric tons (6,702 US tons) of carbon dioxide annually. At current carbon-market values, this would be worth about US$195,000.

According to the model, the subsequent growth of native woodland would store 100 million metric tons of CO₂ across 100 years, "sufficient to make an important contribution to national climate targets".

"Large-scale expansion of woodlands, facilitated through the return of wolves, can contribute to national climate targets and could provide potential economic benefits to landowners and communities through carbon finance," the authors write.

Concerns over wolves in Scotland

Safety issues must, understandably, be considered. The question is deeply divisive, and with good reason.

"Human-wildlife conflicts involving carnivores are common and must be addressed through public policies that account for people's attitudes for a reintroduction to be successful," says ecologist and farmer Lee Schofield, a co-author of the paper.

The team believes that experience from wolf reintroductions in the US and Europe could offer useful lessons. Although wolves' intimidating reputation is not without foundation, ecosystem collapse and severe climate change are hardly harmless alternatives.

"This substantial carbon sequestration and the potential financial benefit related to wolf reintroduction may influence landowner and land manager perspectives around large carnivores," the team writes.

The study was published in Ecological Solutions and Evidence.