Birds & Bats
Cascade Community Wind takes the impact of wind turbines to avian wildlife seriously and do our best to ensure that each of our turbines has a net positive impact. While individual birds can be killed by impacts with wind turbines, studies show that this is relatively rare, and that bird populations are not affected by well placed turbines.
Bird impact is one of the most common concerns about wind turbines and there is one early wind farm in California that has a fairly serious impact on birds. Since then better turbine design, serious consideration of birds in every project and more skillful sighting of wind turbines has led to wind turbines having a very minimal impact on birds such that organizations like the Sierra Club and the National Audubon Society have come out strongly in favor of wind power.
Of the relatively few birds that are killed at wind turbine sites in the Pacific Northwest,69% are birds in the same family as pigeons. Only 7% are raptors, such as hawks, eagles and owls.
While every bird death is something to take seriously, glass windows on our houses are the cause of far more bird deaths than will likely ever occur through wind energy production.
Northwest Bird Impact
Source: Cumulative Fatality Impacts: Synthesis and Approaches to Address Them, Wallace Erickson
This study looked at studies covering 10 large wind farms in Washington and Oregon and gives a pretty good summary of what to expect as far as bird deaths per Megawatt per year. If one of CCWC’s one Megawatt wind projects hits the average for the NW wind farms studies then we would expect about 2 birds per year to be killed about 1/3 of them would be bats and once every 14 years one would be a raptor, the rest would be common song birds. We expect to save more birds than this by avoiding the pollution of fossil fuel based electricity and by our support of local environmental organizations improving habitat. 2% of the net profits from each of CCWC’s turbines is donated to a local non profit such as a local chapter or the Audubon Society, Ducks unlimited, or other organization with the intent to mitigate the small but real environmental and aesthetic impacts of wind turbines. While each turbine does not have sufficient income to support a post installation monitoring program we do invite these environmental groups to do volunteer surveys as well as telling our land owners to report any fatalities. In this way we can learn from existing installations.
NWCC Bird & Bat Fatality Literature Review
A great Summary of avian impact research by the National Wind Coordinating Collaborative can be found at the below link. This report does a good job of showing the complex realities of wind in relation to avian species, while yes the impact is generally low there are exceptions, and there are ways to minimize impact and there are unanswered questions. Cascade Community Wind will continue to follow best practices for minimizing and mitigating avian impacts as more knowledge is made available.
