HEAVY METAL CONCENTRATIONS IN LAKE MICHIGAN PREY FISH
Understanding factors that govern bioaccumulation of heavy metals in Great Lakes fish is critical for understanding ecosystem and human health implications. For example, mercury bioaccumulates in large piscivorous fish, but the trophic pathways leading to bioaccumulation remain poorly understood. We examined the tissue concentrations of heavy metals in Lake Michigan prey fish that differ in life history traits and trophic position. We obtained fish from the 2015 USGS trawl survey for six prey species common to Lake Michigan – Deepwater Sculpin (Myoxocephalus thompsoni), Slimy Sculpin (Cottus cognatus), Bloater (Coregonus hoyi), Alewife (Alosa pseudoharengus), Rainbow Smelt (Osmerus mordax), and Round Goby (Neogobius melanostomus). We measured stable isotope ratios (d15N and d13C), tissue metal concentration (mercury, lead, copper, nickel, zinc, cadmium, arsenic, chromium, manganese, magnesium), and individual fish attributes (total length, weight, body condition, depth of capture, capture location). Tissue metal concentrations differed between nearshore and offshore collection sites, and between benthic and pelagic species, but patterns varied among metals. For example, mercury exhibited a strong positive correlation with trophic position (d15N and d13C) but the magnitude of the effect varied among species.
Whitney Conard (Primary Presenter/Author), Department of Biological Sciences, University of Notre Dame, firstname.lastname@example.org;
Brandon Gerig ( Co-Presenter/Co-Author), Northern Michigan University, email@example.com;
Lea Lovin ( Co-Presenter/Co-Author), University of Notre Dame, firstname.lastname@example.org;
Gary Lamberti ( Co-Presenter/Co-Author), University of Notre Dame, email@example.com;