White spruce demography and herbivory by snowshoe hares measured at latitudinal treeline in the Brooks Range, AK III - Spruce Data

Treelines in Alaska are advancing in elevation and latitude because of climate warming, which is expanding the habitat available for boreal wildlife species, including snowshoe hares (Lepus americanus). Snowshoe hares are already present in tall shrub communities beyond treeline and are the main browser of white spruce (Picea glauca), the dominant tree species at treeline in Alaska. We investigated the processes involved in a 'snowshoe hare filter' to white spruce establishment near latitudinal treeline in the Brooks Range, Alaska. To understand how hare browsing may affect the rate at which seedlings escape herbivory, we measured several demographic attributes of white spruce in, including spruce height, basal diameter, browsing history and age.