Living in a burned landscape: woodland caribou (Rangifer tarandus caribou) use of postfire residual patches for calving in a high fire - low anthropogenic Boreal Shield ecozone

摘要

Environment and Climate Change Canada (ECCC) calculated that 55% of Saskatchewan's Boreal Shield has been disturbed by wildfire in the last 40 years. The 2012 Canadian Federal Recovery Strategy for woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) states that these large-scale natural disturbances can cause caribou to cease use of portions of their range. This assumption neglects the potential habitat value of postfire residuals. We tested this assumption using 2 years of GPS data obtained from 56 female caribou to identify calving site selection. Seventy-nine calving events were identified from 91 individual calving seasons. For both calving and postcalving periods, woodland caribou preferred nonburned (&40 years) over burned habitats (&= 40 years). Within burned areas, residual patches dominated by bogs-fens were preferred, indicating that burns with residuals are important woodland caribou calving habitat. The residuals may act as island refuges providing food-security, while surrounding burns provide reduced visual obstruction from which caribou can detect approaching predators. Although more data are necessary to make robust conclusions, this study provides novel insight into the ecological interactions of forest fires with woodland caribou in northern Saskatchewan, and offers important considerations regarding critical habitat identification and range-level planning to ensure all suitable caribou habitats are identified.