I investigate processes at the ecosystem level using statistical modelling. My main interest in research is to understand ecological processes and population dynamics of aquatic organisms at the ecosystem level, in particular those aspects that are relevant to resource management. Recently I have been investigating spatial and temporal scales needed to study the spatial distribution of fish abundance and obtain indices of abundance of fish populations in marine and freshwater ecosystems. Since fish, as other aquatic organisms, cannot be directly observed large scale population studies must rely on analysis of data from scientific surveys or commercial operations. The analysis of this information requires specialized statistical modeling. Currently my focus is in the Great Lakes.

Research Interests: Numerical Modeling of Coastal Hydrodynamics, Ice Transport and Sediment Transport Modeling, Model Evaluation, Coastal Nowcast/Forecast Systems, Coastal Meteorology, and Physical-biological coupling.

I am an ecologist who combines field and geospatial data and methods to study the pattern and process of ecological systems. I also strive to build bridges between science and social science. What motivates my work is recognition of the complexity of the relationship of humans and ecological systems. These relationships and their emergent properties can be studied at different spatial scales and levels of organization. Knowledge gained from field studies, geospatial data, and analysis can be used to build models that help scientists and to understand the implications of human actions on the social and natural systems of which they are a part.

Dr. Johengen is a research scientist and Associate Director of the Cooperative Institute for Limnology and Ecosystems Research (CILER), which is a NOAA Joint Institute program at the University of Michigan with the NOAA-Great Lakes Environmental Research Laboratory serving as the host lab. CILER's research activities are focused around five themes including: Climate and Large-Lake Dynamics, Coastal and Nearshore Processes, Lare-Lake Ecosystem Structure and Function, Remote Sensing, and Marine Environmental Engineering. Dr. Johengen's individual research interests focus on nutrient cycling and lower food-web dynamics in the Great Lakes, controlling the introduction of invasive species, and development of in situ water quality sensors and observing systems.

I conduct research on the Great Lakes and connecting tributaries including: work with yellow perch larvae in Lake Michigan, work with a remotely operated vehicle on offshore reefs in Lake Michigan to collect evidence of lake trout reproduction, work with exotic species, especially round and tubenose gobies and zebra/quagga mussels, and work with toxic substances, burbot, deepwater sculpin, and larval fish distribution in the Muskegon River. In the past I taught a class at the university entitled: Great Lakes Aquatic Field Methods in May most years and one termed Great Lakes Aquatic Ecosystems.