Winterkill
Winterkill prone lakes are shallow and weedy, with ice cover cutting off oxygen from the atmosphere and deep snow curtailing oxygen production within a lake. In small lakes, an aeration system can do a pretty good job of raising lake-wide oxygen levels. In larger lakes, the higher oxygen level generated by aeration creates a refuge area for fish.
The U.S. Forest Service, in cooperation with the Wisconsin Department of Natural Resources and several lake associations and sportsmen's groups, has installed and currently maintains 10 aerators in the Chequamegon-Nicolet National Forest. Lakes include: Wilson Flowage, Sailor, Twin, Riley, Blockhouse (Price County), Little Clam and Lake Three (Ashland County), Kathryn and Mondeaux Flowage in Taylor County, and Plantation Lake in Oconto County.
The agencies have an active winter dissolved oxygen monitoring program to keep an eye on levels in the winter. The most common system is powered by electricity. It uses an electric air blower, housed in a shore-based shelter building. The blower provides air through a length of galvanized pipe to a series of plastic diffuser lines laid onto the lake bottom. Air is bubbled through the lines to circulate the water and create a large open-water area during ice cover.
March 5, 2007 7:14 AM | Category: Fish