“Great things can happen when researchers are willing to share data.” That’s one of the take-homes for Dr. Virginia Winder, author of a recently released study that examines factors affecting space use by female prairie-chickens. Sixteen researchers contributed to the study, which analyzed nearly twenty years of data on ten populations of greater and lesser prairie-chickens in five states.
Female lesser prairie-chicken (left) wears a satellite transmitter that tracks her movements (photo Jeremy Roberts, Conservation Media).
The study offers important insights about managing prairie-chicken habitat. First, Winder found that prairie-chickens actively select for prairie habitat. While prairie habitat made up 45-89% of the landbase of the study sites (cropland dominated the remaining landbase), prairie-chicken home ranges comprised 70-97% prairie habitat.
As Winder explains it, “prairie-chickens are using the prairie above and beyond its availability, which means they’re actively selecting for it.” Simply put, prairie-chickens need prairie habitat—cropland doesn’t provide a habitat substitute, and interspersing prairie and cropland habitats can affect the way prairie-chickens use the landscape.
Second, proximity to lek sites (springtime mating display areas) was a strong and consistent predictor of space use for female prairie-chickens at all ten sites. More than 95 percent of the 382 females monitored in the study had home ranges centered within three miles of leks during the breeding and nesting period (March through August).
According to Christian Hagen, co-author of the study and science advisor to the Lesser Prairie-Chicken Initiative (LPCI), this finding validates LPCI’s conservation strategy of focusing habitat improvement efforts on the range surrounding lek sites.
“The study substantiates that targeting specific portions of this prairie landscape—in particular, grassland habitat around leks—is the right way to go, across the bird’s distribution,” says Hagen.
Researcher tracks radio-tagged prairie-chickens (photo courtesy David Haukos).
Hagen explains that the females’ choice for nesting and brooding habitat seems to be dictating where males choose to lek. “In the absence of detailed research, leks can provide a strong indicator of the areas important to the viability of the population.”
Third, the data analysis showed significant site variation in the relative importance of other predictors of space use. Winder explains that prairie-chickens are dealt a far different hand in New Mexico than they are in Kansas, in terms of plant composition, rainfall, and levels of human disturbance. The birds respond differently to these varied prairie habitats.
“What we call a prairie in New Mexico is very different from what we call a prairie in Kansas, even though it’s the same bird using both those habitats.” Winder said. This suggests that generalized habitat management guidelines may not always be appropriate for prairie-chickens.
For Hagen, the study brings home the fact that prairie-chickens are truly landscape-scale species, evidenced by the finding that females use a median home range of up to 14.2 square miles of habitat during the breeding season alone. Given their need for landscape-scale habitat, lesser prairie-chickens require landscape-scale conservation—the central aim of the Lesser Prairie-Chicken Initiative.