Floods Trash Popular Wildlife Fefuge
Friday, October 26th 2007, 7:27 am
By: News On 6
MINNESOTA CITY, Minn. (AP) _ Not far from Don's Body Shop and the Alcove Bar is a peaceful, green world that ducks, bald eagles and shorebirds call home.
The Upper Mississippi National Wildlife and Fish Refuge is also a retreat for bird-watchers, canoeists and summertime boaters.
But Mother Nature giveth _ and taketh away.
Days of flash flooding in August along the Minnesota-Wisconsin line left parts of the refuge scarred and pitted.
Birds perch on wrecked cars and jumbled thickets of uprooted timber. Tributary shorelines once covered with lush trees are barren flats smeared with chocolate-colored muck. Thousands of cubic yards of new sediment could threaten the lives of fish this winter and make it hard for aquatic plants to get sunlight next spring.
All in all, federal officials estimate the flooding caused $1.78 million in damage to the refuge, which draws about 3 million visitors every year.
The refuge stretches 260 miles from southern Minnesota to northern Illinois. Established in 1924 as a breeding ground for waterfowl, it is a living laboratory, populated by more than 600 species of plants, more than 160 bald eagle nests and almost 120 species of fish.
``In local areas, it was certainly devastating to the status quo,'' refuge manager Don Hultman said of the floods. ``That kind of rain event hasn't happened in our recorded history.''
Hardest hit was the area around Minnesota City, a town of about 200 people 130 miles southeast of Minneapolis.
Tiny Garvin Brook, a once-peaceful trout stream that meanders past the town and onto the refuge en route to the Mississippi River, swelled to twice its normal size. It erased shoreline forest, tore out a new ravine and left behind huge piles of debris, including thickets of uprooted timber, a crumpled garage door and one wrecked car.
``Anything someone would have in their garage is now out there,'' Mary Stefanski, manager of the refuge's Winona, Minn., district, said as she stood on a cliff recently surveying the damage.
Biologists said the Mississippi's main channel grew dark from new sediment but returned to normal in a few days. Long-term effects on the refuge's ecosystem are unknown, but the biggest immediate problem is new mud in refuge backwaters.
Terry Dukerschein, team leader for the Wisconsin natural resources department's refuge monitoring station in La Crosse, said new sediment left some areas shallower. That could mean less deep water that fish need to survive winter, forcing species elsewhere, and new obstacles for boaters.
The sediment also presents problems for aquatic plants. It likely buried some plants, resulting in lower oxygen levels in the water. The dirt could choke off sunlight to plants next year if it hangs in the water, Minnesota natural resources biologist Dan Dieterman said.
The U.S. Fish and Wildlife Service and the U.S. Army Corps of Engineers have worked to reduce sediment buildup by dredging and building islands to reduce wind erosion in hopes of preventing backwater from filling in and disappearing. All the new muck will make that job harder.
What's more, scientists must watch for effects from chemicals the flood carried in, Dieterman said. ``We have no idea what kind of chemical pollutants may have entered the system,'' he said.
So far, the northern portions of the refuge don't appear to have lost any of their allure. Stefanski said all access points are open and undamaged. Duck hunters are still using the refuge in their usual numbers, and she expects ice fishing and bird-watching over the winter will remain popular.
``There's always give and take,'' Hultman said. ``You're displacing fish. You're displacing wildlife. It won't be as good for some species, but other species will move in and take advantage of it.''
The bare sandbars will be prime roosting spots for shorebirds, particularly the least sandpiper, and are perfect habitat for willows, a small shrub that grows very thick, providing good habitat and cover for the 35 species of warblers that migrate through the refuge.
On the negative side, the new bare spots can attract purple loosestrife, an invasive plant that can crowd out other species.
Federal wildlife officials hope to build support in Congress for cleanup aid, but how long that could take is anyone's guess.
Meanwhile, Stefanski is trying to bring in the nonprofit river cleanup group Living Lands & Waters to remove some of the biggest junk. No date has been set for the group's visit. Hultman said he may ask volunteer groups in the spring or summer to remove as much debris as they can.