What does the Great Recession and the housing market crash have to do with ruffed grouse hunting in Minnesota?

Everything.

The closing of six timber-consuming mills in Minnesota over the past five years has greatly reduced logging and -- if the trend isn't reversed -- will result in an older forest less productive for ruffed grouse and whitetail deer.

"Grouse numbers will go down if timber harvest is curtailed, no question," said Ted Dick, Department of Natural Resources grouse coordinator.

Timber harvest has fallen from a peak of 4.1 million cords in 1994 to an estimated 2.5 million cords this year -- a 39 percent drop. Sluggish demand for wood products used in home construction is blamed for most of the drop.

That means about 80,000 fewer acres of forest -- or 125 square miles -- are being cut now.

"That's 800,000 acres over 10 years," said Craig Schmid, DNR regional forestry manger in Grand Rapids. "It's significant."

Grouse reach their highest densities with a variety of aspen age classes, said Dick.

"If all your forest goes into older age classes, grouse densities will drop," he said. "If the trend continues, it doesn't bode well for the future of grouse hunting."

Hardboard or oriented-strand-board plants in Deerwood, Cook, Bemidji, Grand Rapids and Duluth all closed recently, as did a paper mill in Sartell. Some were closed permanently; others could reopen if the economy improves.

Said Wayne Brandt, vice president of the Minnesota Timber Producers Association: "With less wood being cut, that means fewer acres of young forest habitat, and that's bad for grouse and bad for deer."

And if the forest products industry doesn't cut timber, there are no other management options.

"It's the only tool we have to manage forest cover out there," said Schmid. It would be cost-prohibitive for the DNR to cut timber to manipulate wildlife habitat.

Less logging also affects hunter access.

"Most people are walking logging trails," Schmid said. "Those will be harder to find."

The shift in forest habitat won't be quick, because of the slow growth of forests. It takes five to 10 years for grouse to utilize a newly cut area. So ruffed grouse and grouse hunters will find decent habitat in the next few years.

"You won't notice it overnight, but over time the lower timber harvest level will result in less young aspen," Schmid said.

"If we stay where we are at, the forest will definitely get older. We're losing more wood fiber to insects and disease, and the overall health of the forest will decline."

Rocky Gutiérrez, professor at the University of Minnesota's Department of Fisheries, Wildlife and Conservation Biology, is more optimistic.

"If you believe the economy will never recover, then that's true [grouse numbers will decline]. But if the economy does recover and there's a greater demand for pulp and forest products, then this is a short-term trend."

And, officials say, biofuels made from timber could drive more logging in the future.

Gutiérrez, a grouse researcher, said besides fluctuations in the forest products industry, the future of ruffed grouse also is dependent on the forest management policies of the state and federal governments, the management of small forest parcels by landowners and the potential long-term effects of climate change on the northern Minnesota forest.

The DNR, for example, is trying to increase the proportion of conifers in the forest by 4 percent to 5 percent to attain a more natural forest, which could impact ruffed grouse.

"Sometimes that's at odds with the deer-grouse people, but it's a relatively small amount," Schmid said.

How all of this affects the number of grouse hunters is unknown. But the trend is fewer hunters. As recently as 1998, 142,000 grouse hunters pursued ruffies -- 48,000 more than last year.

But Dick said that regardless of the current trends, grouse and grouse hunting won't disappear.

"It just may not be as good as in some of the heyday years," he said.

Doug Smith • dsmith@startribune.com