Variable effects of snow conditions across boreal mesocarnivore species

Abstract

Mesocarnivores are increasingly recognized as key drivers of community dynamics, but the effects of bottom-up and abiotic factors on mesocarnivore populations remain poorly understood. We evaluated the effects of snow conditions, prey abundance, and habitat type on the distribution of five sympatric mesocarnivore species in interior Alaska using repeated snow-track surveys and occupancy modelling. Snow depth and snow compaction were the best predictors of mesocarnivore occupancy, with differential effects across species. Coyotes (Canis latrans Say, 1823) and red foxes (Vulpes vulpes (L., 1758)) occurred in areas of shallow, compact snow; Canada lynx (Lynx canadensis Kerr, 1792) occurred in areas of shallow, fluffy snow; and wolverines (Gulo gulo (L., 1758)) and marten (Martes americana (Turton, 1806)) occurred in areas of deep, fluffy snow. These findings indicate that altered snow conditions due to climate change may have strong direct effects on the distribution of northern mesocarnivores, with divergent effects across species.