AWWI is pleased to release the 2016 update of Wind Turbine Interactions with Wildlife and their Habitats: A Summary of Research Results and Priority Questions. This document presents current scientific knowledge about the impacts of wind turbines on birds and bats in North America and how to avoid and minimize these impacts.
“The research summarized here is key to understanding and minimizing the impacts of wind turbines on birds, bats, and other wildlife,” said AWWI Director of Research and Evaluation Taber Allison. “At what levels and why do such impacts occur? What are we learning about technologies that have been proposed to avoid and minimize impacts? The research on such questions continues to expand and helps us design solutions to protect wildlife while developing and operating wind energy projects.”
Recent studies, summarized in this 2016 update, mostly confirm or refine previous findings, including:
- Current estimates of fatality rates from wind turbines do not appear likely to lead to population declines in most bird species, although, as some species decline because of a host of other factors, the potential for biologically significant impacts to some species, such as raptors, may increase.
- Small passerines (bird species including songbirds that are under 31 cm/12 in in length, such as sparrows and larks) account for the substantial majority (approximately 60%) of bird fatalities at wind energy facilities in North America.
- Three migratory, tree-roosting bat species (the hoary bat, the Eastern red bat, and the silver-haired bat) account for almost 80% of reported bat fatalities from wind turbines. The population levels of these bat species is poorly known, and the ecological impact of bat fatalities, whether from wind turbines or other causes, is therefore not known.
- There is concern that prairie chickens and greater sage-grouse will avoid wind energy facilities as they do utility poles, roads, and oil and gas platforms, and other development. Studies so far have found neutral, positive, and negative responses to wind energy development.
- The lighting currently recommended by the Federal Aviation Administration (FAA) for wind turbines does not increase collision risk to bats and migrating songbirds.
- The effect of turbine height on bird and bat collisions remains uncertain, with some studies indicating that bat collisions increase with wind turbine tower height, but with conflicting evidence for birds.
- Curtailing (stopping) blade rotation at low wind speeds results in substantial reductions in fatalities of bats.
- Efforts to increase turbine visibility to reduce collision fatalities have met with limited success, and several raptor species have shown little response to ultraviolet light.
In order to meet the highest level of scientific rigor, this Summary builds on peer-reviewed research and is itself reviewed by a team of scientific advisors.
The American Wind Wildlife Institute (AWWI) is a partnership of leaders in the wind industry, wildlife management agencies, and science and environmental organizations who collaborate on a shared mission: to facilitate timely and responsible development of wind energy while protecting wildlife and wildlife habitat. We envision a future where wildlife and wind energy thrive, allowing all of us — wildlife and habitat included — to reap the climate change mitigation benefits that wind energy makes possible.