Diverse environment appeals to prairie chickens
The better job ranchers do managing their grazing land, the better the habitat for wild game birds like the Lesser prairie chicken, according to a research assistant with the Kansas Cooperative Fish and Wildlife Research Unit. John Kraft told ranchers during the Nebraska Grazing Conference that lesser prairie chickens have variable habitat needs, but prefer large, continuous grasslands or native prairie over the CRP and ditch lands preferred by their counterparts, like grouse and pheasants.
“They select different habitats based on whether they are nesting or already have chicks,” Kraft said. In the spring, they prefer bare ground with a mixture of shrubs and sage-type vegetation. “They like spots on top of hills that are open so the males can display and be seen well,” he said. When the birds are nesting, they are looking for areas with the most amount of cover because they don’t want to be seen at all. Once the chicks hatch, they are looking for a medium range of habitat and open ground, so the chicks can move around easier.
The diversity of habitat needed by the birds concerns Kraft because contemporary grazing management strategies lean towards smaller pastures, shorter grazing periods and higher stocking densities. These strategies are becoming more popular among ranchers who want to more uniformly graze their grasslands. “As grazing strategies strive for uniformity in grazing pressure, habitat heterogeneity and biodiversity is sacrificed,” Kraft said. “Although some wildlife species reap benefits of homogenous or uniform grazing disturbance, the costs to species more reliant on variable vegetation structure are significant.”
Creating more and better habitat for the prairie chicken can be accomplished through landscape heterogeneity, he said. “Most commonly, patch-burn grazing has been the management regime of choice for creating landscape and pasture heterogeneity beneficial to grassland wildlife,” Kraft said, while admitting the technique lacks popularity among ranchers. Patch burn grazing is created by controlled burning of a part of the pasture and directing grazing pressure to a smaller part of the pasture to create highly used areas and lower used areas. “Studies have shown recently burned patches have higher forage quality than areas burned three years ago,” he said.
Since the practice is unpopular, an alternative may be utilizing better grazing management practices. Kraft proposes developing pasture heterogeneity through livestock grazing management strategies like pasture deferment, pasture size and stocking density. Utilizing patch grazing, along with placing water and mineral in strategic locations, and managing grazing pressure in multiple pastures can allow producers to better manage wild birds like the prairie chicken.
Kraft thinks producers can use forage quality to drive grazing distribution. He believes producers tend to stock smaller pastures with more livestock, while larger pastures are typically understocked. “If they could stock these pastures so the most pressure is concentrated on high quality forages, it would leave other areas that don’t have a lot of use,” he said.
Studies have shown that modest grazing utilization creates the most habitat for the prairie chicken. “The optimum lesser prairie chicken habitat is what they will use the most. I think it follows the basis of take half, leave half,” he said.
The prairie chickens place nests in the most robust habitat. “There is a low probability of nest placement when the availability of forage drops below 20 percent,” he said. “However, 20 percent forage utilization creates a more desirable nesting habitat. Twenty percent isn’t as plausible as 40-45 percent to a beef producer, but it can create a full variant of habitat structure using these variables.”
The birds could be trying to select from both habitats at one time. One pasture might offer better nesting habitat, like switchgrass that hasn’t been grazed, next to good brooding habitat that has been grazed more. It is a matter of nest success versus bird survival,” Kraft said. “At higher stocking density, you won’t get the increase in heterogeneity, which is driven by grazing selectivity. But, as pasture size increases, there is a higher probability of grazing habitat because we have a tendency to stock larger pastures lighter. With any increase in grazing pressure, we will see a dropoff in nesting habitat,” he added. ❖
— Clark is a freelance livestock journalist from western Nebraska. She can be reached by email at firstname.lastname@example.org.