New research from sites across the Northwoods Rewilding Network, coordinated by rewilding charity SCOTLAND: The Big Picture, shows that rewilding has led to dramatic increases in biodiversity. On rewilded land, the amount of suitable space and habitat for birds increased more than fivefold, while the numbers of bumblebees and butterflies rose by over tenfold. Separate analysis of the network suggested these rewilded landscapes support an estimated 2.5 million pollinating insects. The findings highlight the critical role that long-term nature recovery can play in reversing biodiversity loss and restoring ecosystem resilience in Scotland.

The Scotland-wide chain of over a hundred landholdings has supported £4.2 million in local investment since its launch in 2021. The latest survey looked at recent and historical rewilding action and found striking gains in both the variety and abundance of species, providing some of the strongest evidence yet that rewilding delivers measurable ecological recovery.

Northwoods partners are committed to nature recovery and share a vision for an ecologically restored landscape, where natural processes are reinstated, habitats are better connected and species can recover and thrive. The network is based on a set of key rewilding principles, and seeks to demonstrate how the approach can be applied across different scales and settings, for the benefit of nature, climate and people.

‘Measuring the variety and abundance of different birds, bumblebees and butterflies, our survey set out to answer whether we could demonstrate that rewilding leads to improved biodiversity, and whether we could show this across the Northwoods network,’ explains Northwoods Rewilding Officer, Aidan Maccormick.

Supported by a team of specialist ecologists and surveyors, Aidan undertook multiple survey visits to a total of 11 sites from across the Northwoods network, where there were rewilded areas right next to non-rewilded areas. The team surveyed both the rewilded and non-rewilded areas over spring and summer, to assess birds at five of the sites, and butterflies and bumblebees at a further six others.

‘The results are astonishingly clear,’ says ecologist, Dr Ross Macleod, from Liverpool John Moores University, who analysed the data. ‘We detected bumblebees and butterflies more than 3,000 times, and recorded 1,000 pairs of breeding birds, over 120 kilometres of walked transects. On rewilded land, biodiversity surged across the board, with the number of bird species up 261% and their breeding territories up by 546%. For pollinators, the variety of bumblebee and butterfly species more than doubled, their abundance increased over tenfold, and the number of nectar-rich plants they could use in the rewilded areas rose by around 250%.’

‘We also recorded greater variety and abundance of red and amber listed birds – those of conservation concern,’ continues Aidan. ‘Species such as spotted flycatcher, cuckoo and woodcock are relatively common on Northwoods rewilded areas, bucking the national trend of almost catastrophic declines.’

Several of the successfully rewilded sites are also reaping the benefits of diversifying, like Comrie Croft – a former livestock farm and conifer plantation that’s been converted into a regenerative farm and popular eco-tourism destination. ‘We were keen to create a place where people and nature could thrive side by side,’ explains founder and owner, Andrew Donaldson. ‘Families, jobs, wildlife - it doesn’t have to be either or. It’s hugely satisfying to know that a site that was a nature-depleted, non-native woodland making little money 30 years ago, is now an award-winning, rewilded mountain biking destination that receives 50,000 visitors a year but also supports four times as many birds.’

Argaty Red Kites at Lerrocks Farm near Stirling is another example. The livestock farm doubles up as a rewilding estate, where visitors can enjoy guided tours and spend time in wildlife-watching hides. ‘It’s exciting to know our rewilded areas support ten times the number of bumblebees,’ says owner Tom Bowser. ‘These areas are still essential to our farming business, either forming part of our wildlife watching areas, or being grazed by our beef herd. For us, rewilding is a win for both nature and income. Our native woodlands now support more than 15 times the numbers of birds they used to, they’re home to beavers and red kites, and also provide shelter for our livestock. So they’re essential for a healthy business and a healthy ecosystem.’

‘These results show us that rewilding not only works but is extremely effective,’ continues Aidan. ‘Whether it’s turning a conifer plantation into a naturally regenerating native woodland, or increasing wildflower species in cattle pasture, we have shown that having more native habitats and natural processes leads to higher biodiversity. But just as crucially, we’ve shown that rewilding can work alongside business, from food production to recreation and tourism.’