Lesser prairie-chicken decline concerns biologists
A small number of serious bird watchers worldwide have been privileged to see the mesmerizing dance of the lesser prairie-chicken during their spring breeding season. For others who desire to see this ancient and vocal all-out effort by the prairie grouse, time may be ticking away.
During a daybreak ritual, males seek out ridge tops of expansive prairie land for the booming, gobbling and frenetic display used to socialize and compete for females. Activity on these communal breeding grounds known as "leks," can be heard for a mile or more.
Lesser prairie-chickens once covered the prairie land of the Great Plains where they were an abundant game bird. Now a species in rapid decline, scattered populations are limited largely by the fact that their prairie habitat is also limited. A sustainable population of the lesser prairie-chicken requires about 25,000 acres of adjoining high-quality largely native grassland. And depending on the composition of the landscape, larger areas may be needed.
In Oklahoma, the lesser prairie-chicken has declined to the point of becoming a state species of special concern, vulnerable to extinction from limited range, low population and other factors.
In a unique weekend birding festival in northwest Oklahoma recently, a small but select group gathered to view lesser prairie-chickens on a lek, and to honor a rancher whose conservation efforts are aimed at protecting them and other bird species in decline.
At a presentation on the Selman Ranch, near Woodward, Okla., Dwayne Elmore spoke about the concern the lesser prairie-chicken presents to wildlife biologists.
"I like to call them the grassland canary. Because, like a canary in a coalmine, it is the first thing that goes when there is something wrong with the prairie; so, that is why I am really interested--not just to have another species around. The reason we want to keep our eye on them is because they are our early warning indicator that something is seriously wrong with the grasslands."
The whole western third of Oklahoma, including the Panhandle once teemed with the lesser-prairie chicken, he said.
Elmore, an Oklahoma Cooperative Extension Service wildlife biologist and assistant professor in the department of natural resource ecology and management at Oklahoma State University, was invited to speak to a group of Audubon members gathered to officially designate the Selman Ranch as an Important birding area and honor Sue Selman for her efforts in conservation.
Using a regional map to show known populations of the grouse species as distributed through a five-state area today, Elmore said there has been an overall 90 percent reduction in the species range.
The trend in Oklahoma since the 1980s, according to Oklahoma Department of Wildlife Conservation data, shows a precipitous decline. The species is presently listed by the U.S. Fish and Wildlife Service as warranted for protection and is now under an annual Endangered Species Act review that could upgrade the lesser prairie-chicken listing to endangered. A warranted listing with ESA shows that the FSW has concern over the future survival of the species, but that other species are in more eminent danger of extinction, Elmore said.
"Needless to say, range and population have been greatly reduced," Elmore said. "And the actual situation for the lesser prairie-chicken is not nearly as rosy for Oklahoma as the map suggests."
Because historical figures prior to the 1980s for Oklahoma populations are not available, Elmore said a comparison of populations is not possible. He said there has probably been a threefold or fourfold decline from what it was in the mid-80s.
"They have a strong avoidance of structures. It really doesn't matter what that structure is, whether it is trees, power lines, wind turbines, whatever--they just generally avoid those. There is an increased degree of avoidance ; as the height of the structure increases the avoidance increases--so that is very important when it comes to wind turbines," he said.
Prairie grassland birds evolved in a habitat that was largely wide open and treeless. Expanding agricultural uses including crops and grazing, along with increasing development into former prairie areas has greatly affected that ecosystem and the habitat needed to support a number of these species.
Range for the chicken outside of the small area in northwest Oklahoma presently includes areas in northeastern Texas, the whole southwest corner of Kansas, a small area in Colorado and the eastern tier line of counties in New Mexico, Elmore said.
The NREM department has a website at http://nrem.okstate.edu/index.html with information about programs offered in wildlife ecology and management as well as a newsletter and access to NREM Cooperative Extension publications.