Are burning, grazing bad for prairie chickens in Flint Hills?
04/10/2011 1:04 AM
04/10/2011 1:04 AM
GREENWOOD COUNTY — She flew in from far out on the prairie, instinctually drawn to the low, humming calls that have floated across the spring Flint Hills for centuries.
The hen prairie chicken landed and a dozen male birds danced and pranced and called in crescendo as they vied for her attention.
Minutes later Lance McNew's gentle hands removed the female from a wire trap she had walked into.
She soon flew from sight, carrying a petite tracking collar biologists hope will help keep the iconic birds from possibly vanishing from the Flint Hills.
Prairie chickens are currently struggling. Lacking major changes, the species could vanish from the Flint Hills within 50 years at the current rate of decline, said McNew, a Kansas State University wildlife research biologist.
"In the past four years I have observed near complete reproductive failure," he said. "A prairie chicken has about a 5 percent chance of making it from being in an egg to an adult the next spring."
His research since 2006 shows too many nests and eggs are destroyed before prairie chicks hatch. The few that hatch seldom live long enough to fledge.
Many biologists think intensive burning and grazing practices used in the Flint Hills could be to blame for destroying needed spring habitat. By comparison the birds are thriving in the Smoky Hills, where burning is rare.
The bird's only salvation in the Flint Hills, some believe, is another grassland plan that uses less fire and less beef.
In a few years McNew hopes to have solid answers. Prairie chickens in the Flint Hills produce about one chick per every 10 adult females annually. That equates to an annual decline of about 30 percent in some areas.
"That's no way to sustain a population," McNew said.
Prairie chickens are as identified with the Flint Hills as chin-high bluestem, vivid wildflowers and striking sunsets.
"Prairie chickens are an important part of our wildlife heritage in Kansas," said Ron Klataske, Audubon of Kansas director. "Historical records show them in the millions in places like Iowa and Illinois and they're basically gone now. "
They're important enough that wildlife officials are investing about $860,000 in the four-year study.
K-State and the Kansas Department of Wildlife, Parks and Tourism combined fund about one-fourth the total. The U.S. Fish and Wildlife Service pays the rest from special excise taxes on shooting and hunting equipment.
Ranchers and land managers care enough to open nearly 70,000 acres of Flint Hills land to McNew and four other researchers.
Ranchers are asked to conduct business as usual while researchers place tracking collars on 50 hen prairie chickens per year.
Half the study area gets burned every year. The other pastures are burned on average every third year.
Too much of a good thing
Burning and grazing have been part of a healthy Flint Hills for thousands of years.
Lightning strikes and native people wanting to improve grazing areas have historically burned the Flint Hills. Huge herds of buffalo once grazed the tallgrass. Ranchers and cattle have continued the practice for the past 150 years.
"If it wasn't for ranchers we wouldn't have prairie or prairie chickens," McNew said as he drove through Chase County. "They've taken care of the prairie. We wouldn't be in the middle of the world's largest contiguous tallgrass prairie if they weren't burning and grazing. It would probably all be grown up in brush or cedar trees."
But prairie chickens need cover that's about a foot or more high for successful nesting so the hens and eggs are well-hidden.
In decades past they were able to find enough cover for good nesting.
Now every blade of grass is often burned for miles. Many ranchers also heavily stock cattle in recently burned pastures so cattle can take advantage of the growing grass. McNew and other biologists think intensive burning combined with large numbers of cattle eating the grass down is the one-two punch keeping the bird population down.
Past research shows about 85 percent of the hens nest every spring and lay sizable clutches. But nests in thinner covers are easily found by predators that range from bull snakes to bobcats. Chicks that hatch have no place to hide and usually end up eaten.
Patching the problem
Some ranchers who practice patch burning think it's the way to go.
Brian Obermeyer, of the Nature Conservancy, said they have been using the patch-burning method on the 11,000-acre Tallgrass Prairie National Preserve near Strong City for several years.
They have also stocked fewer cattle on their pastures.
"We've had about a three-fold increase in the number of prairie chickens counted on the (spring breeding grounds)," Obermeyer said. "In 2008 we had somewhere in the low-30s. Last year we had 93 birds."
He said others species of ground-nesting birds and some species of butterflies have improved in numbers.
"Things respond pretty quickly when you give them the right habitat," said Obermeyer.
Flint Hills rancher Bill Browning has been patch-burning on his ranch for about five years and also reports increased numbers.
Jim Pitman, Wildlife and Parks biologist, said population surveys on nearby lands show the birds in decline.
"I don't think it's a coincidence that the increases on the preserve started the same time as the patch-burning," he said.
McNew still isn't sold.
"Those cases are circumstantial evidence," he said. "We need a study like this one to prove things one way or the other."
If the study proves the benefits of patch burning for prairie chicken reproduction he hopes more ranchers will consider that option.
But trying to contain fires is more work than setting them. Browning estimates it takes him more than 20 hours to mow firebreaks around his ranch.
McNew hopes positive findings might encourage state or federal agencies to offer financial incentives to ranchers to encourage patch burning.
Hope for the future
Wednesday morning McNew and Browning sat in a blind on the rancher's land and watched the dozen males dance until the hen walked into a wire cage.
She was quickly fitted with a transmitter that easily tucked within her feathers.
Browning released the bird and watched it sail over the prairie his family has ranched for more than 100 years.
"Thirty-five years ago when we moved into our house you could step out and hear so many prairie chickens in so many directions. They were everywhere but not nearly any more," he said. "I'd sure like to hear it like that again someday."