Wind Energy Threat to Bats Growing

Updated 09/04/2020

The cumulative impact of wind power facilities in killing migratory bats threatens to become an environmental crisis that cannot be ignored (O’Shea et al. 2016). By 2012, more than 600,000 bats were being killed annually (Hayes 2013). By 2014, this number had risen to 2.22 million annually,  and the number is likely substantially higher today (Smallwood 2020). The Bats and Wind Energy Cooperative (www.batsandwind.org) has made outstanding progress in developing credible assessment methodology and potential mitigation techniques. However, there still is no consistent implementation or sufficient guidance on mortality thresholds that should trigger mitigation (Arnett 2012). In most cases, the only mitigation is on behalf of already listed endangered species (negotiated through Incidental Take Permits under Section 10 of the Endangered Species Act).

Management and permitting agreements are often left to the discretion of local entities who have little or no experience in wildlife or other environmental issues, though their decisions can have far reaching national and international consequences. Further complicating matters, there remains a paucity of credible science to document population sizes or forecast long-term mortality impacts, too often leaving costly litigation as the only option for resolving controversy.

Proactive companies who have provided funds and taken risks to help scientists conduct the research required to solve problems are inadequately rewarded, and an unfortunately large number of others have gained an economic advantage by failing to implement even the simplest, most cost-effective mitigation recommendations, for example feathering blades at low wind speeds. This approach can reduce bat mortality by 77 percent over a fall season of 75 nights at a cost of only 1 percent of total annual output (Arnett et al. 2010).

Education at many levels is urgently needed in order for both bats and proactive companies to benefit in time to avoid a costly environmental confrontation. At current rates of wind industry expansion and resulting bat mortality, additional species almost certainly will be driven into endangered status, risking a backlash from traditional environmentalist supporters, not to mention the cost of increased endangered species mitigation and litigation. Though communication with landowners and decision makers can be extremely important, nothing is likely to prove more immediately effective than simple provision of clear industry incentives.

One possible approach to avoiding public demands for heavy-handed government regulation is for conservation and industry leaders to cooperate in developing criteria by which companies can be objectively ranked relative to their collaboration in preventing or mitigating harm to bats, birds and other wildlife. These rankings could be used to help green energy investment advisors guide their clients, many of whom seriously care about the environment. Even investors whose only concern is avoidance of costly delays and litigation likely could be influenced. Such an approach need not require perfection to serve as an important guide in the right direction.

Criteria could include the extent to which a company avoids high-risk locations, incorporates approved mitigation techniques and collaborates with scientists to monitor mortality and improve problem solving techniques.