The effect of renewable energy amplified by habitat change
Increased wind energy development will potentially decrease bat habitat or cause direct mortality with severe effects on Regional Species of Greatest Conservation Need (RSGCN) - including the Silver-haired Bat (Lasionycteris noctivagans), Eastern Red Bat (Lasiurus borealis), Hoary Bat (Lasiurus cinereus), and Tri-colored Bat (Perimyotis subflavus). Additionally, changes in phenology of bats may make it difficult or impossible to create a wind curtailment schedule to reduce bat mortality at wind farms.
Bat fatalities caused by wind energy installments can increase as migration patterns and habitat use shifts in response to climate change. Wind energy installments have the potential to greatly impact bat populations by increasing fatalities by either directly striking bats, or through barotrauma (Sjollema et al., 2014; Friedenberg & Frick, 2021). Barotrauma is a sudden pressure change that damages air-containing organs (Sjollema et al., 2014). Friedenberg and Frick (2021) modeled the effect of terrestrial-installed wind energy on Hoary Bat populations under two build-out scenarios in the U.S. and Canada; suggesting that under high build-out scenarios, Hoary Bat populations could decline by 32-70% by 2025, with some scenarios projecting extinction risk with 40 years.
Bats use offshore habitats during migration and summer months, putting them at risk from expanding offshore wind development (Dowling, 2018; Sjollema et al., 2014). Most fatalities occur between mid-July and October, when migration peaks (Hayes et al., 2015). As climate change shifts migration patterns, studying these responses will be critical for adapting curtailment programs. High mortality rates could reduce genetic diversity and adaptive capacity, accelerating population declines. Minimizing fatalities benefits both wildlife managers and the wind energy industry, as extreme declines could trigger protective policies limiting new development or operations.
Balancing renewable energy goals with wildlife protection will require adaptive, evidence-based management to reduce bat mortality while supporting sustainable energy expansion.
Management Solutions
Solution 1: Proactive curtailment
Proactively curtailing terrestrial wind energy production to wind speeds of 5 m/s can achieve similar outcomes as smaller build-outs to maintain bat population viability and potentially reduce future conflict as curtailment was found to be more socially and politically feasible than reducing wind infrastructure (Friedenberg & Frick, 2021). However, cutoff speeds may be different for offshore wind developments because bats may be active during higher-than-optimal wind speeds so they can return and find terrestrial roosting sites (Sjollema et al. 2014). Models of curtailing offshore wind speeds projected minimal losses of energy production (Dowling 2018), pointing to a balanced solution for both wildlife management and renewable energy expansion.
Solution 2: Acoustic deterrents
Acoustic deterrents are a possible solution, but more research is needed on their efficacy before adopting wider use (Frick et al., 2020).
Solution 3: Research and Monitoring
Research on life-history of bat species, and biotic responses to climate change
Many bat species are data-deficient, so continued monitoring is important to understand how bats adjust to climate change and interact with wind installments (Frick et al., 2020, Hayes et al., 2015). This is particularly true as bat species expand their range (Loeb & Winters, 2013) or change their phenology (Jonasson & Guglielmo, 2016).
Solution 1 and 2 correspond to:
Terrestrial Wildlife Adaptation Menu -Strategy 7.1: Anticipate and manage conflict from increasing populations, range expansions, or changing behaviors.
Tribal Adaptation Menu -Strategy 13: Design and modify infrastructure and access to match future conditions and community needs.
Incorporate natural or low impact development into designs.
Terrestrial Wildlife -7.2 Manage conflict associated with societal adaptations to climate change
Tribal Adaptation Menu -5.4. Reduce negative impacts from anthropogenic disturbances
Solution 3 corresponds to:
Tribal Adaptation Menu Strategy 2: Learn through careful and respectful observation (gikinawaabi).
Tribal Adaptation Menu 2.1. Learn from beings and natural communities as they respond to changing conditions over time.
Tribal Adaptation Menu 7.4. Seek out or share traditional and/or cultural knowledge to inform management of sensitive or at-risk beings or communities.
References
Adapted from
Staudinger, M.D., A.V. Karmalkar, K. Terwilliger, K. Burgio, A. Lubeck, H. Higgins, T. Rice, T.L. Morelli, A. D'Amato. 2024. A regional synthesis of climate data to inform the 2025 State Wildlife Action Plans in the Northeast U.S. DOI Northeast Climate Adaptation Science Center Cooperator Report. 406 p. https://doi.org/10.21429/t352-9q86