Although I am honored to be retained as Professor Emeritus at Iowa State University, I can be reached more easily in my role as Director of the Minnesota Sea Grant Program at University of Minnesota or in my research role at the Large Lakes Observatory on Lake Superior.

A lake is the landscape's most beautiful and expressive feature.  It is Earth's eye; looking into which the beholder measures the depth of his own nature. ~Thoreau

Prospective graduate students: please apply through the Water Resources Science Graduate Program at University of Minnesota




Director, Minnesota Sea Grant College Program

University of Minnesota (Duluth & St. Paul)

Voice: 218-726-8715



download an abbreviated CV

My research interests span the range from aquatic to terrestrial ecology; from microbial ecology to biogeochemistry; and from population conservation to whole ecosystem restoration and management. Scales of study range from the organismal to comparative analyses of ecosystems across the globe. Research in aquatic ecology and limnology is centered upon the highly impacted, eutrophic to hypereutrophic lakes and streams of the US Midwest. These are some of the most nutrient-rich systems in the world and so are perfect testing grounds for current theories concerning aquatic ecosystem structure and function, as well as important foci for restoration. Whole watershed analyses stress the tight links between land use and water quality, utilizing a strong GIS component. The Limnology Lab also is the home of the Iowa Lakes Survey and collects annual data on the water quality of 130+ lakes across the region, yielding an important understanding of the consequences of nutrient extremes. Iowa waters supply significant amounts of nutrients to the Gulf of Mexico, thus the biogeochemistry of our watersheds is of great relevance to marine ecology and oceanography. The conservation of aquatic biodiversity is also a principal interest in my laboratory and several of us study freshwater mussel ecology. Iowa was once a world center for freshwater mussel biodiversity but they are declining precipitously here. We are working to understand the reasons behind their decline around the world.