Mitochondrial DNA Variation and Mixed-Stock Analysis of Recreational and Commercial Walleye Fisheries in Eastern Lake Erie

Abstract

The relative contributions of five spawning stocks of walleye Stizostedion vitreum to three recreational derbies and a commercial fishery operating in eastern Lake Erie in 1995 and 1996 were estimated by analyzing mitochondrial DNA (mtDNA) variation and by using a maximum likelihood model. Simulations of fishery mixtures (N ϭ 100) were used to assess the performance of the likelihood model for estimating contributions from three baselines composed of the five Lake Erie spawning stocks: Chickenolee Reef and Huron River (western basin), Grand River (eastern basin), Van Buren Bay and Smokes Creek (eastern basin). Differences between the simulated mixtures and the mean of the estimates revealed that the model differentiated among varying simulated contributions from the three baselines. Bias among the estimates was greatest when a single baseline contributed entirely to the simulated mixture. Mixed-stock analysis (MSA) of the eastern basin fisheries suggested that the western basin baseline was a major contributor to both the recreational (0.63 Ϯ 0.10) and the commercial (0.81 Ϯ 0.14) fisheries. The eastern baseline contribution estimates were not significantly different from zero, with the exception of the Grand River baseline contribution to the recreational derbies (0.16 Ϯ 0.08). The results are preliminary to show that mtDNA variation and a maximum likelihood model can be used to estimate the relative contributions of walleye stocks to the mixed fisheries of eastern Lake Erie. Further research using comprehensive baselines, including all potential contributing stocks, is recommended before the MSA information presented is used directly for the management of walleyes in Lake Erie. * Corresponding author: michael.gatt@mnr.gov.on.ca 1 Present address: Peterborough District Office, Ontario Ministry of Natural Resources,

Microsatellite and mitochondrial DNA markers show no evidence of population structure in walleye (Sander vitreus) in Lake Winnipeg

“…In randomly-mating diploid organisms, observed heterozygosity (H O ) from the microsatellite data and haplotype diversity (h) from the mitochondrial RFLP data are comparable as measures of genetic diversity (Nei and Tajima, 1981). Average H O for Lake Winnipeg was 0.66 and h was 0.52, values which are comparable to each other, as well as to values found in Cedar Lake (within the Lake Winnipeg drainage: H O = 0.587 by Stepien et al (2009)), and in the Laurentian Great Lakes: H O = 0.686-0.735 (Stepien et al, 2009) andh = 0.447-0.828 (McParland et al, 1999;Gatt and McParland, 2003). This indicates that genetic diversity within Lake Winnipeg is comparable to that found in other large lake walleye populations experiencing similar pressures (e.g., commercial fishing, invasive species and eutrophication), despite the somewhat longer evolutionary history of the Laurentian system.…”

Mixed‐Stock Analysis of Lake Sturgeon in the Menominee River Sport Harvest and Adjoining Waters of Lake Michigan

“…Molecular genetic markers and established methods of statistical inference have been widely used in fisheries management (Carvalho and Hauser 2004;Pella and Masuda 2004) and in other basic and applied sciences (Manel et al 2005). Specifically, mixed-stock analysis has been widely used to provide compositional estimates of harvests from population mixtures in both marine (e.g., Beacham and Wood 1999;Ruzzante et al 2000;Seeb et al 2004) and freshwater (e.g., Gatt et al 2003) realms as well as to quantify spatiotemporal variation in population contributions in habitats occupied during nonspawning periods (Potvin and Bernatchez 2001). While the majority of studies have focused on species of economic importance, increasing attention has been directed towards species of conservation concern (e.g., sturgeon; Waldman et al 1996).…”

Movement of Walleyes in Lakes Erie and St. Clair Inferred from Tag Return and Fisheries Data

“…The interaction of bathymetry, temperature, and food abundance in the three basins in Lake Erie may cause variation in walleye abundance and spatial distribution. Lake Erie walleyes have been managed as a single stock, but are comprised of several genetically distinct stocks (Merker and Woodruff 1996;Stepien and Faber 1998;McParland et al 1999;Gatt et al 2003). Previous tagging studies suggested that walleye stocks in western Lake Erie migrate north to LSC and Lake Huron, while stocks in Lake Huron and LSC also migrate south to Lake Erie through connecting waters (Wolfert 1963;Ferguson and Derksen 1971;Haas et al 1988;Todd and Haas 1993).…”