Factors Affecting the Probability of Bark-stripping by Deer in a Natural Forest: An Analysis Based on Tree Characteristics, Deer Habitat Utilization and Environmental Conditions

Risk factors affecting bark stripping by deer remains unclear, especially in natural forests where effective controls of damage on forestry and forest ecosystems are difficult. We investigated the distribution of debarked trees and the frequency of habitat utilization by deer in the snow melting season in a natural forest located at Furano, Hokkaido. Analyzing these data, we assessed the effects of tree characteristics and surrounding environments on the risk of bark stripping. The susceptibility of bark stripping was negatively affected by stem diameter, even though its basic level was different among species. Ulmus davidiana, which were extremely susceptible to bark stripping, tended to be more damaged in sites with low-elevation, high-irradiance, convex topography and where surrounded by poorly regenerated stands. Also for other species, risk of bark stripping was increased by convex topography and poor regeneration around the tree. These environmental conditions were similar to those conditions which tended to increase frequency of deer utilization. These results suggest higher risk of bark stripping in stands where frequently visited by deer in snow melting season.