Prairie Chickens on Your Open Grasslands
A minimum of 4,000 to 5,000 acres of open grassland is believed necessary to support a stable population. As a result, several well-managed farms are normally required to provide adequate acreage for a self-sustaining flock.
Permanent grass tracts of 160 acres or larger are best, but these may be managed in 10- to 40-acre parcels. Management that leaves grasses standing 10 to 17 inches tall from September through June is critical for winter roosting and nesting. The grasses also should be sturdy enough to withstand strong winds and heavy precipitation. Light grazing during nesting is acceptable. Very light grazing can improve cool-season grasses and create value for nesting and brood rearing. At least 50 percent of the landscape should provide nesting habitat to sustain the population. Burns help keep litter from becoming too thick, but no more than one-third of the total area managed for nesting should be burned in any given year.
Hens occasionally move newly hatched broods considerable distances to reach areas with abundant forbs—particularly to legumes more than 25 inches tall, which provide both a protective canopy and harbor abundant insects. Significant bare ground allows easy movement and open space to dry off from overnight dew. Management aimed at providing nesting sites near suitable brooding habitat helps reduce travel by young chicks and may increase survival.
Woody cover is not important for prairie chickens in winter. However, broods do use low-growing (3- to 10-foot) shrubs to escape summer heat. These shrub clumps should comprise only 1 to 5 percent of the landscape. Trees should be kept to a minimum and confined to riparian (or the lowest) areas in the landscape.
Management of fescue pastures usually involves close grazing that eliminates nesting cover. As a result, fescue offers little habitat of value to prairie chickens. Tall fescue can serve as nesting habitat if it is left idle. However, idle fescue tends to form a monoculture with few insects, making it poor brood habitat. Prairie chickens may use fescue pastures to dry off after rains or heavy dew, but these must be near taller cover that provides some protection from predators.
Native warm-season grass or native prairie remnants provide excellent summer forage for livestock. Burning a different one-fourth to one-third of native grass pastures each spring will focus livestock grazing on the burned portion. This seems to produce competitive livestock gains and both nesting and brood-rearing habitat.
Cool-season hayfields with combinations of timothy, orchard grass, clovers and alfalfa often are used for nesting. Because cutting may occur before most nests hatch in early June, cool-season hayfields may become nesting “traps.” Delaying hay harvest until mid-June will avoid most, but not all, nests. Adults and broods use hayfields for feeding following hay harvest; adults make use of legumes and chicks forage for insects.
Native prairie hayfields also provide brood habitat. However, annual haying does not leave enough cover to provide nesting habitat the following spring. Haying prairie remnants every other year can improve hay yields and provide nesting cover for prairie chickens half the time.
CRP fields and other grasslands not used for agricultural production offer opportunities for prairie chicken management. If planted to native warm-season grasses, a portion of these idle fields must be disturbed each year by mowing, burning or disking to prevent the grasses from becoming too tall and thick. Some non-native cool-season grasses such as timothy, smooth brome and orchard grass mixtures provide suitable habitat and require less frequent disturbance.
However, any idle grass cover has the potential to become too tall and dense in Missouri. Nesting prairie chickens may avoid grasses taller than 30 inches. To improve these grasses for the birds, rotary mow in September to a height of 14 inches. Moderate grazing also can help diversify the structure of these otherwise rank stands of idle grass.