Skip to main content
Dryad

Landscape factors influencing predation on capercaillie nests by two competing mesopredators: pine marten and red fox

Angoh, Siow Yan Jennifer1; Brainerd, Scott Michael1; Devineau, Olivier1; Odden, Morten1; Jahren, Torfinn1

Published Oct 13, 2025 on Dryad. https://doi.org/10.5061/dryad.nk98sf86d

Data files

Oct 13, 2025 version files 29.58 KB

Click names to download individual files

Abstract

Predation by pine martens (Martes martes) and red foxes (Vulpes vulpes) is an important factor influencing the population dynamics of capercaillie (Tetrao urogallus). However, there is a knowledge gap regarding the relative effects of these mesopredators on the reproductive success of capercaillie. To better understand how various landscape factors influence nest predation by pine martens and red foxes, we monitored capercaillie nests in Norway between 2009 and 2014 using camera traps. We classified the fate of 156 nests and employed a cause-specific hazard model to evaluate how different predators contributed to nest predation risk, while accounting for landscape covariates such as distance from nest to forest-clearcut edges, proximity to roads, and agricultural land density. We found that predation by pine martens and red foxes was the predominant hazard to capercaillie nests, with similar daily predation rates observed for both mesopredators. Nest predation by pine martens decreased with increasing agricultural land density and tended to increase along gradients from clearcuts to forest interiors. Moreover, pine marten predation tended to decrease with increasing distance from roads. Nest predation by red foxes increased with distance from roads, but only in areas characterized by high density of agricultural land. Red fox predation was not associated with distance to forest-clearcut edges or to agricultural land density. Our findings show that landscape factors differentially influence pine marten and red fox predation on capercaillie nests and highlight the importance of considering predator-specific effects while managing populations of game birds and their predators.