It^s not as though anyone was really surprised.
Minnesota^s ruffed grouse numbers declined for the second year in a row, indicating that the regular 10-year population cycle identified by wildlife biologists is still in charge of the state^s grouse population.
Statewide, drumming counts were down 40 percent from 2000. The northeast, north and central hardwoods regions all showed similar declines of 45 percent, 42 percent and 46 percent respectively. Grouse drumming dropped in the northwest region by just 13 percent, but that region had seen a substantial drop (35 percent) from 1999 to 2000. The only zone showing no decline was in the southeast, where counts were low but stable.
DNR wildlife biologists attribute the decline to the ruffed grouse^s inexplicable 10-year population cycle, which they have tracked for more than 50 years.
"The extent of this year^s decline," said Bill Berg, DNR wildlife research biologist, "may be partially due to the cold wind chills and severe snow crusting in the north in late winter."
Berg also noted that the wet and cold late spring, when hen ruffed grouse were on their nests, "does not bode well for chick survival this summer."
The grouse survey, which has been run for 52 consecutive years since 1949, tallied the number of drumming male ruffed grouse on 113 routes throughout the species^ Minnesota range.
Berg said that the ruffed grouse^s population cycle will likely continue dropping over the next few years. Despite the decrease, Berg noted that there still should be some excellent grouse hunting in most of the range this fall. "Even with the decline, Minnesota will continue to have the highest population of any state in the country," he said.
The ruffed grouse^s 10-year population cycle occurs naturally, but Berg said that hunters have helped enhance populations overall through hunting fees. Those fees fund DNR habitat programs that provide the birds with additional food and shelter. One such program is cooperative work between DNR wildlife managers and foresters to increase grouse habitat on timber sales of state forest land.
SHARP-TAILED GROUSE NUMBERS DROP Berg also reported that sharp-tailed grouse numbers declined substantially in both zones to near-record lows. After nearly a half decade of slight population increases, sharptail numbers dropped 37 percent range wide. Observers looking for male sharptails dancing on the bird^s traditional mating areas, called leks, noted 43 percent fewer in the east-central range and 30 percent fewer in the northwest range.
Berg said the late winter conditions likely contributed to the decline in sharptails. In recent years, the DNR has increased prescribed burning and shearing that keeps trees from overtaking the open brushlands that sharp-tailed grouse need to survive.
Though discouraged by the decline—northwest sharptail numbers are down 76 percent from 1980 levels—Berg remains optimistic that the bird can recover.
"We^re working on the habitat, but there^s not much we can do about the weather," he said.
Berg also reported that snowshoe hare numbers were at their highest level since 1990 and suggests an upturn in the state^s hare population.
Ruffed and sharp-tailed grouse surveys are conducted each spring by DNR Wildlife Division staff and other cooperators. Trends in the more than five decades of ruffed grouse survey information have verified the 10-year population cycle. Knowing that the natural cycle, and not hunting harvest, is responsible for regular grouse population declines, DNR wildlife managers have been able to increase the hunting season to nearly four months. In the 1940s, before they had survey data, wildlife managers often closed the grouse season to protect populations that fluctuated naturally regardless of season length.
This spring, ruffed grouse drumming routes were completed by cooperators including DNR Wildlife, Chippewa and Superior national forests, Tamarac and Agassiz national wildlife refuges, Camp Ripley, Vermillion College, land departments of Cass and Beltrami counties, Blandin Paper Co., the Ebert Family, 1854 Authority, and Fond du Lac, White Earth, Leech Lake, Red Lake and Mille Lacs Indian bands.
Sharptail dancing ground counts were conducted by staff and volunteers from the DNR Wildlife Division and Agassiz National Wildlife Refuges, and by volunteers from the Minnesota Sharp-tailed Grouse Society.