|Sandhill Cranes fly in close proximity to wind turbines near Horicon National Wildlife Refuge in east-central Wisconsin, but to date no crane mortality has been associated with turbines in this area.|
|Sandhill Crane (Grus canadensis)|
The current placement of wind energy towers in the central and southern Great Plains may have relatively few negative effects on sandhill cranes wintering in the region, according to a U.S. Geological Survey study published today.
Midcontinental sandhill cranes are important to sporting and tourism industries in the Great Plains, an area where wind energy development recently surged. Scientists with the USGS compared crane location data from the winters of 1998-2007 with current wind tower sites in Texas, Oklahoma, Kansas and New Mexico prairies. Findings showed only a seven percent overlap between cranes and towers, and that most towers have been placed in areas not often used by cranes during the winter.
“Great Plains wetlands are critical to preserving valuable sandhill crane populations,” said USGS scientist Aaron Pearse, the study’s lead author. “Our findings can help managers minimize risks of future wind energy development to cranes by highlighting potentially hazardous locations.”
Using data from cranes tagged with satellite transmitters, the scientists estimated wintering crane distributions and habitat selection behaviors prior to and during wind tower construction, which began in 1999 but surged from 2004-2013. They then compared the early estimates with post-construction bird behaviors and current tower locations.
“Although about 50 percent of cranes in our study used locations that had wind towers nearby – within 10 kilometers, or about 6.2 miles – there were few instances in which high densities of cranes and high densities of towers coincided,” Pearse said.
The study further showed:
- A modest seven percent overlap between study areas visited by cranes during the winters of 1998-2004 and areas with wind towers constructed during 1999-2013;
- When they spent time near wind towers, the wintering cranes maintained an average distance of 6.5 kilometers, or about four miles, from the towers;
- Only five percent of wind towers in the Texas High Plains have been constructed in locations identified as highly preferred crane winter habitat; and
- Wintering cranes generally selected wetlands or upland areas near wetland basins.
Eighty percent of the midcontinent sandhill crane population resides in the central and southern Great Plains for up to half of the year. Potential threats of wind towers to cranes include collisions and avoidance of areas near towers, which reduces available roosting and foraging habitat.
For more information about USGS sandhill crane research, please visit the USGS Northern Prairie Wildlife Research Center website.