Red foxes enhance long‐term tree growth near the Arctic treeline

Abstract Recent climate warming is expected to increase tree growth and productivity, substantially altering ecological function boundaries in northern ecosystems. Although largely determines the range of trees any biome, variations microsite conditions can influence on a finer scale. Red foxes ( Vulpes vulpes ) are found most terrestrial ecosystems considered ecosystem engineers through their denning activities. Added soil nutrients from prey remains, feces, urine could benefit dens subarctic regions by alleviating nutrient limitations. We examined white spruce Picea glauca growing eight red fox paired control sites at Arctic treeline. Radial was 55% higher for than between 1897 2017, despite similarities ages densities. This enhanced more pronounced younger trees, consistent with decrease age among all trees. By promoting near treeline, may act as hotspots reproduction. impacts depend spatial distribution dens, predators create distinct microhabitats across landscape, leading increased vegetation persisting over many decades.