Ruffed grouse counts still high; sharp-tail count decreases slightly

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Ruffed grouse counts still high; sharp-tail count decreases slightly
(Released June 20, 2011)

Minnesota’s ruffed grouse spring drumming counts were higher than last year across most of the bird’s range, according to a report released by the Minnesota Department of Natural Resources (DNR).

“The grouse population is probably still near the high end of the 10-year cycle because drumming counts this spring were between the values observed during 2009 and 2010,” said Mike Larson, DNR research scientist and grouse biologist. “Drum counts from the last three years haven’t followed the same smooth pattern as during the previous two peaks in the cycle, but relatively small changes in the index may be due to factors other than the density of grouse.”

Those factors could include weather, habitat conditions, observer ability and grouse behavior.

Ruffed grouse populations, which tend to rise and fall on a 10-year cycle, are surveyed by counting the number of male ruffed grouse heard drumming on established routes throughout the state’s forested regions.

This year observers recorded 1.7 drums per stop statewide. The averages during 2009 and 2010 were 2.0 and 1.5 drums per stop, respectively. Counts vary from about 0.8 drums per stop during years of low grouse abundance to about 1.9 during years of high abundance.

Changes in drumming counts compared to those during 2010 were not statistically significant. The averages, however, increased 18 percent in the northeast survey region, the core and bulk of grouse range in Minnesota, to 1.9 drums per stop. They also increased 16 percent to 2.1 drums per stop in the northwest and 32 percent to 0.4 drums per stop in the southeast. Grouse counts decreased 17 percent to 0.8 drums per stop in the central hardwoods region.

Minnesota frequently is the nation’s top ruffed grouse producer. On average, 115,000 hunters harvest 545,000 ruffed grouse in Minnesota each year, making it the state’s most popular game bird.

During the peak years of 1971 and 1989, hunters harvested more than 1 million ruffed grouse. Michigan and Wisconsin, which frequently field more hunters than Minnesota, round out the top three states in ruffed grouse harvest.

One reason for the Minnesota’s status as a top grouse producer is an abundance of aspen and other ruffed grouse habitat, much of it located on county, state and national forests, where public hunting is allowed. An estimated 11.5 million of the state’s 16.3 million acres of forest are grouse habitat.

For the past 62 years, DNR biologists have monitored ruffed grouse populations. This year,

DNR staff and cooperators from 15 organizations surveyed 125 routes across the state.

Sharp-tailed grouse counts decrease slightly

Sharp-tailed grouse counts in the northwest survey region decreased approximately 16 percent between 2010 and 2011, Larson said. Counts in the east-central region declined approximately 18 percent.

Observers look for male sharp-tails displaying on traditional mating areas, called leks or dancing grounds.

This year’s statewide average of 10.2 grouse counted per dancing ground was similar to the long-term average since 1980. Last year’s average of 10.7 grouse per dancing ground was down from the 2009 average of 13.6, which was as high as during any year since 1980.

During the last 25 years, the sharp-tailed grouse index has been as low as seven birds counted per dancing ground.

Overall, sharp-tail populations appear to have declined over the long term as a result of habitat deterioration. In recent years, the DNR has increased prescribed burning and shearing that keep trees from overtaking the open brush lands that sharp-tailed grouse need to thrive.

The DNR’s 2011 grouse survey report, which contains information on ruffed grouse and sharp-tailed grouse, is available online.