A seven-year study by a Kansas State University ecologist and his team has found wind energy development doesn’t ruffle the feathers of greater prairie chicken populations, according to a news release.
The researchers — led by Brett Sandercock, professor of biology — discovered the grassland birds are more affected by rangeland management practices and the availability of native prairie and vegetation cover at nest sites than by wind turbines.
Unexpectedly, the scientists also found female survival rates increased after wind turbines were installed.
Sandercock and his team were part of a consortium of stakeholders — including conservationists, wildlife agencies and wind energy companies — who studied how wind projects influence grassland birds.
The team started the study in 2006 with three field sites that were chosen for wind development: a site in the Smoky Hills in north-central Kansas, a site in the northern Flint Hills in northeastern Kansas and a site in the southern Flint Hills in southern Kansas.
The Smoky Hills site — the Meridian Way Wind Power Facility near Concordia — was developed into a wind energy site, which gave researchers the opportunity to observe greater prairie chickens before, during and after wind turbine construction. The researchers cooperated and collaborated with private landowners at each site.
The researchers studied the birds for seven breeding seasons and captured nearly 1,000 total male and female birds around lek sites, which are communal areas where males gather and make calls to attract females. Females mate with the males and then hide nests in tall prairie grass.
The scientists researched many different features of prairie chickens and their biology: patterns of nest site selection; reproductive components, such as clutch size, timing of laying eggs and hatchability of eggs; survival rates; and population viability.
The results are somewhat surprising, especially because similar studies have shown that oil and gas development affect prairie chickens, Sandercock said.
With wind power development, the researchers had the unexpected result of female survival rates increasing after wind turbines were installed, potentially because wind turbines may keep predators away from nest sites.
Female mortality rates are highest during the breeding season because females are more focused on protecting clutches than avoiding predators, Sandercock said.
The researchers also found that conservation management practices seem to have the strongest effect on the birds, he said. Prairie chickens are ground-nesting birds and need adequate cover for their nests to survive. Grazing and fire management practices can affect how much nesting cover is available for chickens.
The team is conducting follow-up studies to test mitigation strategies that may improve habitat conditions for prairie chickens. They are in their third season in a field study of patch burn grazing in Chase County and how it affects prairie chickens and grassland songbirds.
The final project report can be viewed at http://www.osti.gov/bridge/product.biblio.jsp?osti_id=1080446.