Reintroducing wolves to Scottish Highlands could help address climate emergency

Reintroducing wolves to the Scottish Highlands could lead to expansion of native woodland which could take in and store one million tonnes of carbon dioxide (CO2) annually, according to a new study.

A team of researchers led by the University of Leeds modelled the potential impact of wolves in four areas classified as Scottish Wild Land, where growing red deer populations eating tree saplings is suppressing natural regeneration of trees and woodland.

They used a predator-prey model to estimate that the reintroduction of wolves to areas in the Cairngorms, South-west Highlands, Central Highlands and North-west Highlands would lead to a total population of around 167 wolves – enough to reduce red deer populations to a level that would allow trees to regenerate naturally.

We need to look at the potential role of natural processes such as the reintroduction of species to recover our degraded ecosystems.

Wolves controlling the red deer population could lead to an expansion of native woodland that would take up one million tonnes of CO2 each year – approximately 5% of the carbon removal target for UK woodlands that the UK’s Climate Change Committee suggest as necessary to reach net-zero by 2050. 

The researchers estimate that each wolf would lead to an annual carbon uptake of 6080 tonnes of CO2, making each of the predators "worth" £154,000, using accepted current valuations of carbon.

The results of their study are published in the journal Ecological Solutions and Evidence.

This is the first time that the potential impacts of wolf reintroduction on woodland expansion and carbon storage in the UK have been assessed, and the researchers believe the results provide further evidence of the role large carnivores can play in delivering the nature-based solutions required to address the climate emergency.

Lead author Professor Dominick Spracklen at the School of Earth and Environment said: “There is an increasing acknowledgement that the climate and biodiversity crises cannot be managed in isolation. 

“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.”

Loss of native woodland

Wolves were eradicated from Scotland around 250 years ago, leaving red deer with no natural predators and allowing their populations to grow across the country. Despite ongoing management, red deer numbers in Scotland have significantly increased over the last century, with the latest estimates thought to be as high as 400,000.

Lack of natural tree regeneration has contributed to the long-term decline and loss of native woodland. Scotland today has one of the lowest levels of native woodland in Europe, with only 4% of the country covered.

The natural regeneration of trees is largely restricted to areas where deer are excluded by fences. More intensive deer management in some locations has been shown to help tree regeneration, with an increasing number of seedlings when red deer numbers were reduced to fewer than four per km2.

Discussions around potential large carnivore introductions to the UK and elsewhere are ongoing. The wolf population in Western Europe now exceeds 12,000 and they occupy 67% of their former European historical range, including human-dominated landscapes in Central Europe.

Even the Netherlands, a country considerably more densely populated than Scotland now has wolves resident again.  

The researchers recognise that the debate around the reintroduction of wolves to the Scottish Highlands will not be without controversy, particularly among livestock farmers and deer stalkers.

However, they argue that the benefits of reintroducing wolves need to be considered. The financial benefits associated with carbon uptake and storage would be in addition to the other well-documented economic and ecological impacts of wolf reintroduction, including ecotourism, a reduction in deer-related road traffic accidents, a reduction in Lyme disease associated with deer and a reduction in the cost of deer culls.

Lee Schofield, a co-author of the study, farmer and author, added: “Our aim is to provide new information to inform ongoing and future discussions about the possibility of wolf reintroductions both in the UK and elsewhere.

“We recognise that substantial and wide-ranging stakeholder and public engagement would be essential before any wolf reintroduction could be considered. Human-wildlife conflicts involving carnivores are common and must be addressed through public policies that account for people’s attitudes for reintroduction to be successful.”

Further information

• Read ‘Wolf reintroduction to Scotland could support substantial native woodland expansion and associated carbon sequestration’ in Ecological Solutions and Evidence
• For media enquiries, please contact Kersti Mitchell in the University of Leeds press office via k.mitchell@leeds.co.uk
• More Faculty of Environment news.