Rice and Ducks in the Land of 10,000 Lakes

DU is restoring the natural productivity of Minnesota's historic wild rice lakes

a

Photo © Justin Skrzynski

DU is restoring the natural productivity of Minnesota's historic wild rice lakes

A half mile of paddling and we entered the lake, or rather rice field, for we could not see any water save the narrow stream we were pushing our boat in. At the first report of the gun, (fired at a stray mallard which got up in a hurry and came down again in like fashion) the mallards and teal arose with a noise like thunder all around us and all over the rice fields as far as we could see, and for two hours, as fast as we could keep the breechloaders going, we had rare sport, while our friends on shore kept up a fusilade, and assisted by their dogs, made a good bag. "Haviland," Forest and Stream magazine, ca. 1878.

Every part of this vast continent has its unique wetland habitats and waterfowling experiences. In Minnesota—the Land of 10,000 Lakes—this habitat is shallow lakes containing wild rice. Natural wild rice historically grew from northern Iowa east to Michigan and in boreal forest lakes and ponds in Canada, as well as in much of Minnesota. Humans have capitalized on this tasty, nutrient-rich seed for thousands of years, and Native American ricing camps have been identified on many of the larger rice lakes.

Although humans continue to harvest wild rice, it is the waterfowl that use these rice lakes that draws Ducks Unlimited to their shores. More than any habitat in the forested wilds of Minnesota, it is the wild rice lakes that attract large concentrations of waterfowl. Breeding species—mallards, blue-winged teal, ring-necked ducks, wood ducks, Canada geese, goldeneyes, and black ducks—but also migrants passing through for only short periods in the fall and spring, such as pintails, wigeon gadwalls, and scaup; all are drawn to these shallow lakes for the nutritious grain and the heavy cover provided by rice beds. It is truly a perfect waterfowl habitat, providing food and cover for both breeding and migrating waterfowl.

Fall counts of selected rice lakes in the state have shown enormous numbers and densities of waterfowl, especially mallards and ring-necked ducks.

But all is not completely rosy in the woods of Minnesota. First, detailed scientific data on waterfowl and wetland ecology in Minnesota forests are lacking. There have not been systematic surveys of wild rice or breeding waterfowl abundance in the forests, so long-term trends are hard to identify. Second, while the region still looks intact at first glance—it is, after all, still mostly composed of woods and water—the nature of the habitat has changed dramatically. Intensive silviculture has fostered a younger forest—one that is not, perhaps, as beneficial to cavity-nesting wood ducks. Third, development of recreational land is exploding. Wild rice lakes are seeing more and more cabins and seasonal homes on their shores.

This development tends to degrade water quality, reduce desirable vegetation, and increase disturbance to waterfowl, resulting in reduced value to wildlife. Finally, even nature seems to be running amok. Beavers—long viewed as a friend of the ducks—are having, instead, a detrimental impact on wild rice lakes. By plugging lake outlets with their dam-building activities, they raise water levels and drown out rice during the critical spring growing season. Low pelt prices, abundant young forests for food, and generally fewer trappers have allowed the beaver population to explode to likely its highest level ever.

Ducks Unlimited biologists in the Great Plains Region have initiated a number of efforts to better preserve and manage this unique wild rice resource, in collaboration with the Minnesota Department of Natural Resources (DNR) and other partners. To ensure that development does not permanently destroy this limited resource, DU has worked with DNR to acquire two lakeshore tracts in the past year. Conservation staffers are diligently working to find additional funds for more land-protection efforts. It is estimated that 30 percent of the land adjacent to the 60,000 acres of wild rice lakes in the state is in private hands and susceptible to development. DU's goal is to acquire 7,500 acres of critical shorelines in the next decade.

Acquiring lake outlets is even more important, as managing water levels of these outlets is essential to rice production. In some cases, construction projects are undertaken—generally to rectify damaged outlets previously impacted by human activities (e.g., ditches or road culverts).

But it is the beaver that is causing the most immediate problem. While documentation is scarce, wildlife biologists believe the abundance of rice diminished during the 1990s, primarily in response to increased beaver activity. In 2001, DU and the DNR collaborated on a pilot study to see if it was feasible to remove beavers and their dams from the outlets of a subset of the 70 percent of wild rice lakes with previously protected shorelines to encourage rice growth. Contractors worked on 19 lakes to remove beaver dams at the outlets of lakes to allow waters to free-flow. In order to prevent new dams from being created, trappers removed some nuisance beavers from the same sites. Even though it was a wet summer—normally bad for rice growth and production—there was a favorable response on the managed lakes, and a good rice crop was produced.

With the technique proven feasible, DU and the DNR expanded the effort in 2002 and 2003 to as many as 80 lakes. Heavy summer precipitation again in 2002 reduced success, but a drier year in 2003 lead to a bumper crop of wild rice—some say the best in two decades. By managing these 80 lakes, DU biologists were able to affect some 25,000 acres of rice habitat—almost half the entire acreage in the state. Early indications are that the fall migration use of the lakes has been spectacular.

By creating an ongoing program (at a relatively inexpensive cost of less than $100,000), DU biologists have been able to use the best local trappers—folks who work year around. Since they know they will be working on the same lakes year after year, the trappers concentrate their efforts on these lakes during the regular trapping season, ensuring pelts are prime. Relatively few beaver are trapped in the summer—when pelts are of no value—and only when absolutely necessary and under DNR permit.

DU's goal is to maintain the current program to manage beavers and water levels of previously protected wild rice lakes to sustain their productivity. We also are planning to greatly expand the land-protection program to secure the remaining unprotected wild rice lake shorelines with funding from private donors and government agencies. This resource is critical to the future of waterfowl in the woods of Minnesota, and there is a narrow window of opportunity to protect it given the recreational development pressures. With good fortune, DU and our partners will ensure the "Land of 10,000 Lakes" includes a good measure of those with wild rice.

By Tom Landwehr