Empirical evidence that diversionary feeding increases productivity in ground-nesting birds.

The recovery of predator populations may negatively impact other species of conservation concern, leading to conservation conflicts. Evidence-based solutions are needed to resolve such conflicts. Robust, large-scale field experiments provide the most rigorous evidence to justify new forms of intervention. Still, they are hard to implement and often call for indirect and non-invasive monitoring. In this study, we used camera traps to experimentally evaluate diversionary feeding to reduce conservation conflict and non-invasively monitor capercaillie hen productivity over 3 years under a randomized control (unfed) and treatment (fed) design. Diversionary feeding significantly increased the probability that a detected hen would have a brood. Brood size decreased over time, but the change did not differ between fed and unfed treatments. Importantly, the increased chance of having a brood with diversionary feeding substantially increases overall productivity at the end of the sampling season. This was just 0.82 (0.35-1.29) chicks per hen without diversionary feeding, and more than doubled to 1.90 (1.24-2.55) with diversionary feeding. This study provides compelling empirical evidence that diversionary feeding positively affects productivity, offering an effective non-lethal solution to the increasingly common conservation conflict where both predator and prey are afforded protection.