Teaching Interests

BSC 111 Principles of Biological Sciences I
BSC 340 Environmental Biology
BSC 440/L/540/L Ecology
BSC 443/L/543/L Freshwater Biology

Research Interests

My principal research interests are in freshwater ecology and the ecology of freshwater invertebrates. Much of my research has dealt with the ecology of large rivers such as the Ohio and the Mississippi, and my graduate students and I continue to work on these major rivers. Earlier researchers had contended that the sand substrates of large rivers were depauperate in terms of invertebrates. Research conducted in the lower Mississippi River by one of my graduate students showed that this contention was an artifact of inadequate sampling procedures, and that there were actually very high densities of invertebrates in the sand substrates. At present we are studying the zebra mussel invasion of the major rivers of the Mississippi River drainage. Our major field sites are located in the upper Mississippi River where we work in conjunction with researchers from the U.S. Army Corps of Engineers Waterways Experiment Station and divers from the Tennessee Valley Authority. In addition to our main channel investigations, we have studied a number of the Mississippi's backwater lakes over several years. The research in my laboratory has diversified over the years. In addition to our large-river work, my graduate students and I have become heavily involved in determining the habitat value of aquatic macrophytes, and in studying macrophyte-invertebrate interactions in lakes. Our research findings indicate that not only do abundant, diverse invertebrate epifaunas occur on the plants, but also that the presence of macrophytes markedly enhances infaunal invertebrate densities. Most of this research has been conducted in Eau Galle Lake, Wisconsin. We also used the Eau Galle River as a site to investigate the effects of impoundment on riverine invertebrates. Currently, we are investigating the invertebrates present in ponds on Horn Island, a barrier island off the coast of Mississippi. The island has a large number of ponds of varying salinities that possess an interesting mixture of freshwater and saltwater invertebrates. We are also beginning an ecological study of sand-bottom streams in Mississippi.

Current Graduate Students

Representative Publications

Beckett, D. C., B. W. Green, & S.A. Thomas. 1996. Epizoic invertebrate communities on upper Mississippi River unionid bivalves. Am. Midl. Nat. 135:102-114.

Beckett, D. C. 1992. Phenology of the larval Chironomidae of a large temperate Nearctic river. Journal of Freshwater Ecology 7: 303-316.

Beckett, D. C., T. P. Aartila, & A. C. Miller. 1992. Contrasts in density of benthic invertebrates between macrophyte beds and open littoral patches in Eau Galle Lake, Wisconsin. The American Midland Naturalist 127: 77-90.

Beckett, D. C., T. P. Aartila, & A. C. Miller. 1992. Invertebrate abundance on Potamogeton nodosus: effects of plant surface area and condition. Canadian Journal of Zoology 70: 300- 306.