Avian and Bat Mortality at Wind Installations

MetricTypical ValueHotspot ValueNotes
Bird fatalities (per MW/yr)1.319Median/Max, US field surveys
Bat fatalities (per MW/yr)350Median/Max, US field surveys
Total US bird deaths/yr0.6-1.5MAll wind facilities
Total US bat deaths/yr1.7-2.8MAll wind facilities
Bat fatality reduction (curtailment)44-54%Up to 80%Cut-in speed 5-5.5 m/s
Energy loss (curtailment)<2%1% (targeted)Annualized
Bird fatality reduction (blade painting)Up to 70%Species/site-specific
Eagle fatality reduction (shutdowns)Up to 80%Targeted shutdowns

Invertebrate and Pollinator Response

MetricChangeNotes
Arthropod abundance (post-construction, 2 yrs)-50%Direct mortality, habitat loss
Pollinator abundance (5 yrs, restored)+10-30%Above pre-disturbance, with best practices
Restoration time to baseline3-5 yrsNative flowering strips, minimal mowing
Panel stow or adaptive mowingEssentialMaximizes recovery, reduces disturbance

Vegetation Structure and Trophic Cascades

MetricObserved ChangeNotes
Small mammal density (≤200m from turbines)-20-40%Habitat simplification
Raptor displacementUp to 1 kmHawks, owls, long-term studies
Functional connectivity (no corridors)-30%Grassland specialists, 50 MW solar
Connectivity restoration (corridors)+15-25%Vegetated strips, mosaics
Mesopredator release riskIncreasedLowered small mammal abundance
Data: Arnett et al. 2024; AWWI 2025; Forister et al. 2023; Mola et al. 2024; Prevedello et al. 2023; McRae et al. 2023; peer-reviewed syntheses.

Biodiversity and Ecological Connectivity