Benjamin S Leonhardt

I am Biological Science Technician in the Deepwater Program at the Great Lakes Science Center in Ann Arbor, MI.

My primary field work duties include working on large vessels for annual forage fish (bottom trawl; acoustic and midwater trawl) and gillnet surveys on Lakes Michigan and Huron.

Primary laboratory duties include processing and aging bony structures of prey fish collected in trawl surveys (alewife and bloater) and large bodied fish collected in trawl and gillnet surveys (lake trout, burbot, lake whitefish, cisco, yellow perch). I brought over my expertise of aging large-bodied fishes that I learned from USFWS and Ohio DNR to USGS and started aging programs for lake trout, burbot, lake whitefish, cisco, and yellow perch using a variety of methods (maxilla, otolith, spines). I have interest in investigating other aging methods for species in our current aging program and those that we do not currently age.

Another primary duty is to extract and decode Coded Wire Tags (CWTs) from the snouts of hatchery lake trout collected in annual surveys. Once decoded, the CWTs provides managers and researchers with a multitude of information, like age, strain, stocking location etc.

I have interest and experience in understanding the trophic ecology of predator fishes in the Great Lakes that I gained from my Master's Thesis at Purdue University. I am currently involved in multiple projects that involve lake trout and burbot diets in and around the Northern Refuge in Lake Michigan.

I also assist Research Fisheries Biologists with data collection, data analysis, writing, and reviewing annual reports and manuscripts for publication.