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With nesting and brooding, the researchers found no evidence that wind turbines had any effects on where the females built their nests or took their broods. Interestingly, researchers observed that the chickens were less likely to place their nests near roads; most hens nested at least half a mile away. When studying the chickens' movement within their home ranges, data again provided no suggestion of any kind of avoidance of the wind farm. The birds moved freely around the turbines. In March and April of 2013, technicians also gathered fresh feces of male greater prairie-chickens after watching their behaviors. This information was analyzed by a graduate student mentored by Dr. LaReesa Wolfenbarger at the University of Nebraska-Omaha. In the end, they found no evidence that the wind turbines had any effects on the birds' stress hormone levels. Mammalian predators of various species were also observed at trail camera sites. Data has determined that the surveys provided weak evidence that coyotes, specifically, were avoiding wind turbines. Similarly, the raptor surveys showed weak evidence that avian predators were avoiding the turbines as well. These findings did not translate into any increased or decreased survival of hens, according to Powell. Hens that were spending more time closer to the wind turbines had the same survival probability as hens that spent more time farther away from the turbines. "There may be potential for turbines to change predator dynamics, but we didn't find any effects of the turbines on survival on hens using that landscape," Powell said. However, observations of male greater prairie- chickens suggest a different hypothesis. To study behavior, researchers separated behaviors into two categories: breeding and non-breeding. Breeding behaviors include aggression, combat, getting into position to dance, and showing off to a female. Non- breeding behaviors include standing, feeding, and feather maintenance. What the researchers found was that male greater prairie-chickens closer to the wind turbines spent less time in non- breeding behaviors, and therefore they spent more time displaying breeding behaviors than males farther away from the wind turbines. "One non-breeding behavior is actually standing and scanning for predators instead of being engaged in mating," Powell explained. "So the prairie chickens have to fight and display, but they also have to stop and check out the scene every once in a while to make sure that they're safe. One idea to explain that is maybe they don't have to stop as much to check out for predators in the air because there are fewer predators in the air." Powell and his team also found some compelling data from the sound recordings of the prairie chickens booming, which were sent to acoustic experts Dr. Edward J. Walsh and Dr. JoAnn McGee at the Boys Town National Research Hospital in Omaha for analysis. In addition to gaining a solid baseline on sound at different distances from the lek, there were a few aspects in the birds' vocalizations that were affected. Male prairie chickens that were closer to the wind turbines displayed booms that were longer in duration and with higher sound pressure levels. "So basically, the amount of energy they were using to produce their boom – you can almost think of it as how much they were shouting to boom – was higher," Powell said. Furthermore, ambient background noise was also recorded before the chickens arrived in the early mornings. The acoustic experts found that the ambient background noise that was half a mile away from the wind farm was significantly higher than on other leks farther away. This evidence suggests that the chickens closer to the turbines are perceiving additional sound, which would explain why they were "shouting" more. How will these findings affect the wind-power industry in Nebraska? "If anything, our results will make it potentially a little easier for wind energy. But people seem to be proceeding with caution, but maybe with a little less anxiety on some fronts," Powell said. "That NPPD site was one of the first to be built, so it's a smaller facility. Now, some of these are built with 105 or 110 wind turbines. That's the next question. So if this wind farm would've been 105 instead of 36, would there have been differences? We don't know. Even with what we found, I think there is still a bit of caution to extrapolate that there are no effects of wind energy on prairie chickens." Decisions Come spring, the wind turbines will continue to hum while the prairie chickens take up dancing again. Busloads of photographers and birders will arrive in the Sandhills to witness this remarkable ritual – an earnest display of romance that has captivated so many hearts. These birds are one of the prairie's greatest enchantments, and through partnership between all who depend on and love this landscape, hopefully we will be able to enjoy the prairie chickens' charms for a long time yet. Having spent the last 15 years studying the Sandhills, Powell's work is not possible without cooperation from landowners, as 97 percent of Nebraska is privately owned. "It's the decisions that people are making on their farms and ranches that drive what goes on in our wild landscapes. Hopefully, we've given a bit more information to folks to help them make those decisions." ■◗ NOVEMBER 2016 • NEBRASKAland 51 Hunting Prairie Chickens • Grouse season, which includes prairie chickens and sharp-tailed grouse, begins Sept. 1, 2016 and ends Jan. 31, 2017. • Along with a hunting permit and habitat stamp, a special grouse permit is required to hunt on the east zone (east of U.S. Highway 81). West zone hunting requires no special permit. • East zone daily bag/possession limit is 3/3 birds and West zone is 3/12. • Check the 2016 Hunting Guide for more information. Find online hunter education at huntsafenebraska.org.