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Dr. Jan-Michael Hessenauer

PhD Alumni

Currently a Fisheries Research Biologist

       with the Michigan Dept. of Natural Resources

       at the Lake St. Claire Fisheries Research Station   


My research interests broadly include fisheries management, and population genetics. Specifically, I am interested in evaluating the effects that recreational angling has on the target population(s) with respect to population characteristics and genetics.


At UConn my dissertation research used population genetics, individual metabolic rates and angling vulnerability to contrast exploited and unexploited populations of largemouth bass (Micropterus salmoides).  Largemouth bass have been at the center of recent research exploring the population effects of recreational angling in the context of fisheries induced evolution. Much of this work has been performed using artificially selected strains and small ‘hatchery pond’ experimental populations. My work was intended to provide crucial comparisons and contrasts using wild populations that vary in angling history. 


Connecticut is somewhat unique in that there are several water supply reservoirs that have been closed to fishing since they were built almost 100 years ago. We were moving individuals out of one such reservoir to conduct an introgression experiment. This experiment involved stocking individuals from two populations (one exploited and one unexploited) into a small lake open to fishing.  After each of the next two spawning seasons we collected age-0 individuals and determined the population of origin of their parents using genetic assignment techniques.  Our objective was to determine the fitness of the parental stocks, the nature of the introgression (i.e., dominated by mothers or fathers), and the potential for supplemental stocking of unfished individuals to influence population genetic diversity.  Additionally, we conducted a common garden experiment where age-0 bass from exploited and unexploited populations were raised in the same pond. We then quantified the degree of difference in basal metabolic rate and angling vulnerability among populations with different historical angling pressure. 




My dissertation project was funded by the Connecticut Department of Energy and Environmental Protection Inland Fisheries Division through the SportFish Restoration program and the University of Connecticut Department of Natural Resources and Environment through a James V. Spignesi Memorial Fellowship. I collaborated closely with CT DEEP personnel, and Dr. Amy Welsh at West Virginia University.






For additional information about the Largemouth Bass Project, visit the project page - "A New State Quo in the Catch-and-Release Era"



Wildlife and Fisheries Conservation Center
Department of Natural Resources and the Environment
University of Connecticut
1376 Storrs Road, Unit 4087