Moist soils project provides beneficial wetland habitat for ducks, shorebirds

ROSEAU RIVER WILDLIFE MANAGEMENT AREA, Minn. - Trying to practice conventional farming on low ground is a challenge during wet years, so managers of the Roseau River Wildlife Management Area in northwestern Minnesota are working to turn the negative into a positive by making the land more attractive for ducks and shorebirds.

The 75,000-acre WMA has established a half-dozen "moist soils" habitat sites on 110 acres near refuge headquarters that in recent years has been too wet to grow crops.

"These wet years made us start looking: 'Is there something we can do that is good wildlife management instead of beating our heads against the wall, and take what we've got and make the best of it?'" said Randy Prachar, manager of the Roseau River WMA. "This moist soils (work) might fit the bill once we've got the infrastructure in place."

According to Prachar, moist soils management, in a nutshell, allows managers to flood and draw down sites using levees and control structures to regulate the water. When the water subsides, the resulting mudflats produce plants such as smartweed, wild millet and slough grass that are attractive to waterfowl.

Once the plants establish seed, the land is reflooded to a depth of 6 to 9 inches, either through runoff or by pumping in water. The shallow water also is rich in invertebrates that provide food for nesting puddle ducks, ducklings and a variety of shorebird species, Prachar said.

Managers then can alternately flood and draw down the sites as needed.

"These ephemeral shallow wetlands are what produce ducks," Prachar said. "In Minnesota, a lot of these have gone away. You have to start somewhere."

Ideal site

Prachar said the Roseau River sites -- or "cells," as he calls them -- are ideal for moist soils habitat because they're adjacent to a large impoundment that offers a reliable source of water and upland ground that provides nesting cover.

The six moist soils cells also are located in a sanctuary, off limits to public access, where waterfowl can roost and use the habitat without interruption.

"It's adding that component we didn't have right on-site before -- a good food source next to nesting cover," Prachar said. "If you're deliberate about how you manage that water, you can have a pretty good result for waterfowl.

"Because of the proximity of our habitats, this is a component of our management that could boost duck production here."

That's especially true for puddleduck species such as mallards, Prachar adds.

"This isn't going to attract ringneck ducks and canvasbacks," he said. "This is mainly puddle duck management."

Despite its potential, Prachar said moist soils management is intensive.

"You've got to be there," he said. "You've got to babysit these things."

The six moist soils sites at Roseau River WMA were funded by state bonding, or public works, dollars the Legislature allocates. Prachar said engineers determined the location of the dikes based on the contour of the land.

Construction began in the winter of 2008-2009 and, after wet weather last spring interrupted work, the sites were completed last October, Prachar said. There's still some fine-tuning to be done, he said. Some of the sites are large enough to require a second control structure, and crews also are taking steps to reduce erosion in some areas.

"We're still trying to figure things out," he said.

Southern practice

Moist soils management long has been a popular tool in the southern and mid-latitude states, but it's still relatively uncommon in northern states such as Minnesota. Prachar said he knows of only a handful of other moist soils sites in the state, including Thief Lake WMA near Middle River, which he also manages, and Lac Qui Parle WMA in western Minnesota.

"The problem is the north has such a short growing season," Prachar said. "We probably can't get the same production" as states farther south.

Prachar said he fielded a few telephone calls during construction of the habitat sites from people wondering what was going on. That was especially the case when wet weather delayed construction and muddy, partially completed dikes left the area looking like an eyesore.

Another question, of course, is why moist soils sites are necessary when the land already is too wet. But weather is cyclical, and Prachar said he remembers walking across the nearby Roseau River during the late 1980s and barely getting his feet wet.

"Someday, we will dry up again, and this will be even more important," he said.

According to Prachar, plans are in the works to establish additional moist soils sites, perhaps by tapping into Lessard-Samms Outdoor Heritage Council funding that resulted from a small tax increase Minnesota voters approved in 2008 for natural resources, parks and the arts.

The beauty of moist soils management, Prachar said, is that once the infrastructure is in place, wildlife benefits are created at a fraction of the cost of traditional crop management.

Shallow wetlands also can be managed by less intensive means such as mowing and tilling when they're dry enough. Projects at Thief Lake and Roseau Lake WMAs have proven to be real attractive to birds, he said.

"In the long run, moist soils management, where feasible, is a pretty efficient way of providing waterfowl benefits," Prachar said.

Dokken reports on outdoors. Reach him at (701) 780-1148; (800) 477-6572, ext. 148; or send e-mail to bdokken@gfherald.com .