Response by wintering mule deer and other species to low-volume parial cutting every 30 years in interior douglas-fir forest in Central British Columbia

Summary: "In the early 1980s, wildlife managers were concerned about the effects of traditional timber harvesting methods on the sustainability of mule deer (Odocoileus hemionus) populations in interior Douglas-fir (Pseudotsuga menziesii var. glauca) forests within the central interior of British Columbia. Research on habitat requirements and a low-volume, single-tree selection silvicultural system experiment at Knife Creek near Williams Lake, B.C. helped inform legal management requirements for mule deer winter range. In 2013-2014, 30 years after the first harvest entry at the Knife Creek site, the long-term effects of the original harvest were assessed using winter track counts, an index of relative habitat preference, on the original transects of the 1984-1991 study. A second harvest entry in the single- tree selection system was conducted in 2014. Post-harvest winter track densities were measured from 2015 to 2019. Mule deer track densities were similar among the first post-harvest period (1984-1991) and second entry pre-harvest period (2013-2014) in the original single-tree selection and no-harvest control treatments, which suggests that the first harvest entry had no long-term effects on mule deer winter habitat use. Pre-harvest (2013-2014) track densities of mule deer and red squirrel (Tamiasciurus hudsonicus) were similar among the single-tree selection and no-harvest control treatments, which further supports evidence of no long- term effects. Winter habitat use by mule deer and red squirrel appeared to be unaffected by the 2014 harvest entry: track densities were similar in both treatments during both moderate (25-40 cm) and deep (>40 cm) snow conditions from 2015 to 2019. Post-harvest track counts for marten (Martes americana) and coyote/fox (Canis latrans/Vulpes vulpes) were much lower during deep snow conditions than moderate conditions in both treatments. This study demonstrates that mule deer winter habitat can be successfully managed using the low-volume, single-tree selection silvicultural system with set minimal residual basal area targets and a 30-year cutting cycle. Furthermore, a diverse community of winter wildlife species continued to use the partially cut forest post-harvest."--