Several wetland wildlife habitat improvement projects completed this year at the Dry Sand Lake State Wildlife Management Area will enhance aquatic vegetation and habitat for waterfowl shore birds, sand hill cranes, and trumpeter swans.
The Dry Sand Lake WMA is located on the Cass and Wadena County boundary 12 miles north of Staples. The 400-acre unit encompasses Dry Sand Lake and is managed primarily for natural wetland resources. It is bounded by the Lyons State Forest, Cass County tax-forfeited and Potlatch land. It provides several square miles of conservation lands for public use.
The existing variable crest water control structure was built in the 1960's to restore the Dry Sand Lake basin. The DNR repaired the structure by replacing a rusted 6-foot outlet culvert, filling in the related washed-out dike, retrofitting the water level management capabilities of the structure and adding rip rap to the final dike repair, said Gary Drotts, DNR area wildlife manager. This repaired and modified water control structure will allow the DNR to manipulate the water level of the Turtle Shell basin on the south side of Dry Sand Lake.
"These improvements will enhance aquatic vegetation for waterfowl habitat as well as shore birds, sand hill cranes, and trumpeter swans," Drotts said. "It will also provide food sources for migrating waterfowl."
A second water control structure is in the process of being installed in the beach ridge ditch between Dry Sand Lake and the Turtle Shell impoundment to help manage both the 20-acre Turtle Shell impoundment basin and the 300-acre Dry Sand Lake basin.
This structure is a small fixed crest earth/rock dam that will be installed at the original creek bed elevation, which existed before this lake was drained. This small dam along with the rehabilitation of the original Turtle Shell basin structure will allow for independent water level manipulation of the 20-acre Turtle Shell basin and the restoration of natural water level fluctuations in the 300-acre Dry Sand Lake basin.
A floating cattail mat was tilled to further enhance and improve wetland wildlife habitats and to expand open water areas in the Dry Sand Lake basin. During the early 1900's and before this lake was initially restored in the 1960's, low water conditions caused by ditching allowed cattails to take over much of the shallow areas of this wetland basin. This turned a 300-acre basin from mostly open water to a basin filled primarily with cattails. To create a better mix of open water and cattails again, several areas in the cattail mat were tilled in August while the water was drawn down due to the washed out dike. Once this wetland basin is re-flooded next spring, untilled areas of the cattail mat will float, whereas tilled areas will provide open water areas for waterfowl and other wetland wildlife.
On the terrestrial side, jack pine on the beach ridge between the Turtle Shell basin and Dry Sand Lake were harvested, stumps removed, and the beach ridge seeded to native prairie grass. This was undertaken to return the plant community to an oak savanna, the predominant vegetation type around the wetland during the early 20th century prior to fire protection. Oak savanna is a fire regime community composed of prairie grass and fire resistant oak. The entire Dry Sand Lake and Turtle Shell basin areas along with some upland edges were treated with a prescribed burn in 1999 to enhance the oak savanna community surrounding the wetlands, Drotts said.
Lastly, as structure rehabilitation was going on, various low spots in the primary access road to this unit from Wadena County Highway 30 were repaired and a small gravel pad was added to the carry-in water-access site on the south side of Dry Sand Lake. Contract portions of these projects were primarily funded by $50,000 in State Duck Stamp monies. A sign noting this contribution by Minnesota waterfowl hunters was erected at the Turtle Shell structure site. Additional funding for project supervision, supplies, fleet and other support needs were provided by various Game and Fish Funds, for example Operations and Maintenance, Small Game License Surcharge, and Reinvest in Minnesota (RIM) monies.
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