An innovative conservation technique is bringing renewed hope for one of Scotland’s rarest birds after a new study revealed a 130 percent rise in capercaillie breeding success.
Using a method known as diversionary feeding, scientists and land managers have been able to double the chances of capercaillie hens raising broods in the wild.
With little more than 500 capercaillies left in the UK, this ground-breaking work in the Cairngorms could prove vital to the survival of the species.
Instead of targeting predators like pine martens with lethal control, researchers provided them with deer carrion during the short nesting window to reduce their impact on capercaillie nests.
The results were dramatic.
In areas where food was offered, 85 percent of hens were seen with chicks.
In areas without feeding, that figure dropped to just 37 percent.
Overall, productivity more than doubled from 0.82 to 1.90 chicks per hen.
The work was carried out by a partnership involving the University of Aberdeen, University of St Andrews, Forestry and Land Scotland, RSPB Scotland, NatureScot and Wildland Ltd, under the banner of the Cairngorms Connect Predator Project.
Dr Jack Bamber, who led the research at the University of Aberdeen, called the results compelling and said the approach aligns with modern ethical goals in conservation.
He believes the technique could benefit other threatened species facing similar pressures.
The deer carrion was only provided during the key eight-week period when hens are nesting and chicks are hatching.
By focusing the feeding window and using by-products from ongoing deer culling, the project ensured the approach remained sustainable and avoided boosting predator populations.
Dr Chris Sutherland of the University of St Andrews praised the collaborative nature of the work, saying the close involvement of wildlife managers helped ensure findings were both rigorous and practical.
Colin Leslie of Forestry and Land Scotland said the technique allows the organisation to avoid other forms of predator control, which have had limited success in the past.
He noted the combination of strategies from fence removal and habitat restoration to non-lethal predator management has led to an overall improvement in breeding success even as predator numbers have stabilised.
The strategy is now being deployed at 15 sites and is expected to be rolled out more widely across the Cairngorms National Park by 2026.
Kenny Kortland, project lead for Cairngorms Connect, described the research as a breakthrough in shifting predator behaviour and giving capercaillies the space to breed successfully.
At RSPB Scotland Abernethy, where diversionary feeding is now a core part of the work programme, the capercaillie population has been slowly increasing for five years.
Richard Mason, site manager at Abernethy, said the combination of feeding, habitat management and reduced human disturbance is giving the birds a real shot at recovery.
Carolyn Robertson, Cairngorms Nature Manager, said the results offer renewed optimism and will strengthen the Capercaillie Emergency Plan going forward.
The study was funded by the NERC SUPER Doctoral Training Partnership, with support from the University of Aberdeen and Forestry and Land Scotland.
