Abstract
Wind turbines have been hypothesized to affect bat populations; however, no comprehensive analysis of bat mortality from the operation of wind turbines in Canada has been conducted. We used data from carcass searches for 64 wind farms, incorporating correction factors for scavenger removal, searcher efficiency, and carcasses that fell beyond the area searched to estimate bat collision mortality associated with wind turbines in Canada. On average, 15.5 ± 3.8 (95% CI) bats were killed per turbine per year at these sites (range = 0-103 bats/turbine/yr at individual wind farms). Based on 4,019 installed turbines (the no. installed in Canada by Dec 2013), an estimated 47,400 bats (95% CI = 32,100-62,700) are killed by wind turbines each year in Canada. Installed wind capacity is growing rapidly in Canada, and is predicted to increase approximately 3.5-fold over the next 15 years, which could lead to direct mortality of approximately 166,000 bats/year. Long-distance migratory bat species (e.g., hoary bat [Lasiurus cinereus], silver-haired bat [Lasionycteris noctivagans], eastern red bat [Lasiurus borealis]) accounted for 73% of all mortalities. These species are subject to additional mortality risks when they migrate into the United States. The little brown myotis (Myotis lucifugus), which was listed as Endangered in 2014 under the Species At Risk Act (SARA), accounted for 13% of all mortalities from wind turbines, with most of the mortality (87%) occurring in Ontario. Population-level impacts may become an issue for some bat species as numbers of turbines increase.