Research in the Cairngorms NP has shown that non-lethal predator management can significantly boost breeding success for Western Capercaillie:

Diversionary feeding of predators boosts Capercaillie breeding success
Research in the Cairngorms National Park has shown that non-lethal predator management can significantly boost breeding success for Western Capercaillie. The three-year study revealed that with the number of chicks per female more than doubled in areas with diversionary feeding taking place. With fewer than 550 individuals left in Britain, there is a serious risk of Western Capercaillie becoming extinct for a second time nationally.