MANHATTAN — Wind power development does not ruffle the feathers of greater prairie chicken populations, according to the results of a seven-year study from a Kansas State University ecologist and his team.
The researchers — led by Brett Sandercock, professor of biology — discovered that wind turbines have little effect on greater prairie chickens, and that these grassland birds are more affected by rangeland management practices and by the availability of native prairie and vegetation cover at nest sites. Unexpectedly, the scientists also found that female survival rates increased after wind turbines were installed.
“We don’t have evidence for really strong effects of wind power on prairie chickens or their reproduction,” Sandercock said. “We have some evidence for females avoiding the turbines, but the avoidance within the home range doesn’t seem to have an impact on nest site selection or nest survival.”
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.
“What’s quite typical for these birds is most of the demographic losses are driven by predation. We can say that with confidence,” Sandercock said. “What’s a little unclear from our results is whether that increase in female survivorship was due to the effects of wind turbines on predators.”
The researchers also found that conservation management practices seem to have the strongest effect on the birds, Sandercock 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.
“A lot of what drives nest survival is the local conditions around the nest,” Sandercock said. “Do they have good nesting cover or not? Our results are important because they suggest ways for mitigation.”