Dr. Timothy W Stewart

Associate Professor
Tim Stewart image

Principles of Biology, General Ecology; Natural History of Iowa Vertebrates; Ecology of Freshwater Invertebrates, Plants, and Algae; Field Ecology Research and Teaching

Research and Scholarship
I’m an aquatic community ecologist.  Current research focuses on describing interactions between physical, chemical, and biological variables in wetlands, and developing improved methods for assessing wetland condition (i.e., the capacity of the ecosystem to support high biological diversity).  All research projects involve undergraduate and graduate students. 

Additionally, I'm collaborating with faculty in my department and in the ISU School of Education to develop a program focused on methods of teaching ecology.  This program was initiated in Fall 2016 with a new course, "Field Ecology Research and Teaching", in which undergraduate students develop and complete research projects, adapt these research projects into teaching activities, then develop lesson plans and engage various learner groups (e.g., K-12 students, general public) in field settings.  


Selected Research Publications

Baldwin, R.C., Sundberg, M.D., Stewart, T.W., and Weber, M.W. 2018. Influence of sieve mesh size on relationships between macroinvertebrate assemblage and environmental variables in wetlands. Wetlands 38:677-687.

Sundberg, M.D., Baldwin, R.C., Stewart, T.W., and Weber, M.W. 2018. Responses of wetland ecosystems to drought-induced fish eliminations. Wetlands 38:703-710.

Sundberg, M.D., Baldwin, R.C., Stewart, T.W., and Weber, M.W. 2016. Linkages between land use, invasive fishes, and prairie pothole wetland condition. Wetlands 36:1097-1107.

Maurer, K.M., Stewart, T.W., and Lorenz, F.O. 2014.  Direct and indirect effects of fish on invertebrates and tiger salamanders in prairie pothole wetlands. Wetlands 34:735-745.

Hentges, V.A., and Stewart, T.W. 2010. Macroinvertebrate assemblages in Iowa prairie pothole wetlands and relation to environmental features. Wetlands 30:501-511.

Stewart, T.W., and Downing, J. 2008. Macroinvertebrate communities and environmental conditions in recently constructed wetlands. Wetlands 28:141-150.


Area of Expertise: 
Aquatic Ecology
Aquatic Systems
B.A., Biology, Ithaca College, 1989
M.S., Biology, SUNY Brockport, 1993
Ph.D., Biology, Bowling Green State University, 1999
136 Science II