Behavioral effects of wind farms on wintering Sandhill Cranes (Grus canadensis) on the Texas High Plains

Texas has a superior annual capacity for wind power which has led to the erection of multiple wind farms across Texas with many more facilities planned. Wind energy is vital for a shift to carbon-emission free energy, however there has been relatively little research investigating the effects of wind farms as disturbance factors across the landscape. This project examines how wind energy infrastructure affects Sandhill Crane (Grus canadensis) behavior including landscape level habitat uses.

Sandhill cranes are known to avoid areas of human activity and wind farms have been shown to render surrounding habitat of up to 1 km unsuitable to other species through direct effects (destroying habitat) and indirect effects on (avoidance). I examined the distribution of cranes at multiple wind farms on the Southern High Plains of Texas. I evaluated the effects wind farms have on roost occupancy, habitat use and crane behavior by comparing areas with wind turbines to those without for presence of cranes at roosting sites and behavior of cranes at foraging sites.

I found that cranes within wind farm plots exhibited more vigilant behavior and less resting behavior. The distance to the nearest turbine contributed to 18% of the variation in the percent of cranes seen resting. Crane density and flock size are both negatively correlated with distance to turbines. Cranes in the vicinity of wind farms were found in smaller flocks, in larger habitat patches and closer to the road than cranes in control plots. Cranes also showed different habitat preferences within wind farms plots, utilizing non-foraging habitat which they avoided in control plots. Surveying playas in Texas using occupancy modeling methods resulted in no combination of variables explaining crane presence or absence in playas.

To make effective management and conservation decisions, managers must be furnished with tools that help them understand large-scale ecological processes. Evaluating crane risk to wind farms based on behavioral characteristics can be used to predict areas of avoidance and help preserve important crane habitat in a rapidly developing landscape.