Results from more than two decades of research by NDSU professor Malcolm Butler and his students are being used to help determine optimum ways to manage and restore a regional lake managed for migratory waterfowl. Lake Christina, located in Douglas County near the town of Ashby in west central Minnesota, has provided decades of living ecological lab experience for NDSU students.
Butler, professor of biological sciences at NDSU, is one of 10 co-authors contributing to “a 200-year perspective on alternative stable state theory and lake management from a biomanipulated shallow lake” to be published later this summer in Ecological Applications. A preview of the article is available to subscribers at www.esajournals.org/doi/abs/10.1890/11-1485.1.
Lake Christina is nationally recognized as a critical staging area for migrating waterfowl, especially canvasback ducks. The lake alternates between cloudy and clear, depending on whether there are aquatic plants known as macrophytes or if there is high phytoplankton density.
NDSU students who worked on Lake Christina through the years worked closely with the Minnesota Department of Natural Resources. Mark Hanson, who earned his doctorate from NDSU in 1990, is a co-author of the journal article, now works as a research scientist for the Minnesota Department of Natural Resources. Kyle Zimmer, who earned his doctorate from NDSU in 2001, also is listed as a co-author of the article, works on Lake Christina while a professor at the University of St. Thomas.
“NDSU has had a long involvement with Lake Christina, going back to 1985,” Butler said. “At that time, the Minnesota DNR planned a dramatic restoration project on this historic waterfowl lake, by attempting a total eradication of fish. The 4,000-acre shallow lake had been similarly treated in 1965, with additional treatments in subsequent years.”
As the research being published in Ecological Applications describes, repeated treatments had the expected result: water clarity was restored, plant beds recovered and waterfowl use increased – but not permanently. To understand what has happened after conditions deteriorate, continuous data like that provided by Butler and his students is needed.
The lead authors of the research paper from the Science Museum of Minnesota, William Hobbs, Joy Ramstack Hobbs and Toben Lafrançois, brought expertise as paleolimnologists, studying cores of lake sediments to determine Lake Christina’s historical behavior. The lake is designated as a Wildlife Management Lake and is managed for migratory waterfowl. Managers walk a fine line, balancing short- and long-term needs, and balancing the interests of ducks and duck hunters at Lake Christina with those of recreational anglers. In fall 2012, top-down management will include a series of pumps and pipes installed to draw down the water level, mimicking the natural winter fish kill.
“The study presents compelling evidence that, in the long run, managers need to focus on strategies that target landscapes, not just the food webs in the lakes themselves – bearing in mind that the short term is also important,” said Mark Hanson, a research scientist with the Minnesota Department of Natural Resources and NDSU graduate. “The people who live here today are very much in this culture of ducks and migratory water birds, and the incredible history around them. When we get all sectors working on lake ecology together, that’s a very productive basis for the future.”
Students at NDSU, in collaboration with the Minnesota Department of Natural Resources, contributed significant contemporary data to this project from long-term monitoring efforts at Lake Christina. The U.S. Fish and Wildlife Service and other agencies provided previous funding for the research. Funding for the most recent research was provided by the National Science Foundation (DEB-0919095; DEB-0919070; DEB-0918753) and the Natural Sciences and Engineering Research Council of Canada.
NDSU is recognized as one of the nation's top 108 public and private universities by the Carnegie Commission on Higher Education.