**The title, authors, and abstract for this completion report are provided below.  For a copy of the completion report, please contact the GLFC via e-mail or via telephone at 734-662-3209**



Genetic Stock Structure of Lake Whitefish in Northern Lake Michigan and Green Bay



Brian L. Sloss1, Justin A. VanDeHey2, Trent M. Sutton3, Paul J. Peeters4, and Philip J. Schneeberger5


1 U.S.G.S, Wisconsin Cooperative Fishery Research Unit, College of Natural

Resources, University of Wisconsin-Stevens Point, Stevens Point, WI 54481

2 Wisconsin Cooperative Fishery Research Unit, College of Natural Resources,

University of Wisconsin-Stevens Point, Stevens Point, WI 54481

3 University of Alaska Fairbanks, School of Fisheries and Ocean Sciences

245 O’Neill Building, Fairbanks, AK 99775

4 Wisconsin Department of Natural Resources, 110 South Neenah, Sturgeon

Bay, WI 54235

5 Michigan Department of Natural Resources, 484 Cherry Creek Road,

Marquette, MI 49855



Lake whitefish (Coregonus clupeaformis) have comprised an important commercial fishery on Lake Michigan since the early 1800s. Concerns exist regarding the commercial harvest of potentially shared stocks by Michigan and Wisconsin state licensed and Tribal commercial fishing operations. Previous studies indicated potential stock structure, however, questions still exist regarding the number, identity, distribution, and discreteness of lake whitefish stocks in Lake Michigan. The objectives of the study were to determine if lake whitefish microsatellite and mitochondrial DNA genetic diversity was sufficient to discriminate among spawning stocks of lake whitefish and if the genetic population structure of spawning lake whitefish aggregates in northern Lake Michigan and Green Bay could be delineated in terms of genetic stock identification and degree of stock isolation. Distinct spawning aggregates were assumed to represent potential stocks and differences at molecular markers were assumed to describe population differentiation. Twelve resolved microsatellite DNA loci exhibited adequate levels of diversity for population differentiation in terms of their allelic richness and heterozygosity, met Hardy-Weinberg equilibrium expectations and were subsequently considered useful for population differentiation. Two mitochondrial DNA gene regions (D-loop and ND5) exhibited low sequence diversity (π = 0.0002 and 0.0025, respectively) and low numbers of haplotypes (7 and 5, respectively). The observed diversity did not meet a priori levels of genetic diversity deemed necessary for population differentiation and mtDNA data was not further pursued. Genetic stock identification using the 12 microsatellite loci resolved between 5 and 7 potential genetic stocks. The resolved stocks corresponded to geographically proximate populations clustering into genetic groups. Analysis of molecular variance (AMOVA) suggested six genetic stocks present in the lake. Within stock analyses (pairwise Fst) suggested all but one stock delineated by AMOVA was a stable grouping (i.e., no between population differences) with the exception being a Hog Island and Traverse Bay grouping (NOE stock). This putative stock showed significant differences between the two populations indicating gene flow between a Naubinway-Epoufette stock (NOR stock) and Hog Island but not between NOR and Traverse Bay. Elk Rapids was the most genetically divergent population and actually masked the isolation by distance that exists between all other populations within Lake Michigan.  Genetic mixture analysis showed mixed stock analysis using the resolved stocks and molecular markers can be accomplished with high accuracy. The coupling of genetic data from this study with current demographic data and a comprehensive mixed-stock analysis could allow for more efficient and effective management of this economically and socially important resource.