Historical and Contemporary Gene Flow and the Genetic Structure of Muskellunge in the Ohio River Drainage

Abstract

Muskellunge Esox masquinongy is a recreationally important species distributed throughout the Ohio, upper Mississippi, and Great Lakes drainages and has been introduced outside of its native range. We conducted a survey of microsatellite DNA variation among 11 populations, natural, managed, and hatchery, in the Ohio River drainage. Microsatellite DNA variation was highly significant among all populations. A CLUSTER analysis identified K = 2 populations corresponding to populations east and west of the Ohio River. This may be a consequence of different management practices by Ohio and West Virginia or may suggest that the Ohio River is a substantial barrier to gene flow. A comparison of historical and contemporary gene flow suggests little change in genetic exchange among populations. Our results further support the use of locally adapted broodstock in further management and supplementation of Muskellunge populations.

Combining population genomics and forward simulations to investigate stocking impacts: A case study of Muskellunge (Esox masquinongy) from the St. Lawrence River basin

“…Low survival and/or reproductive success of stocked fish has been reported mostly in salmonid species characterized by putatively high rate of local adaptation (Araki, Cooper, & Blouin, ; Araki et al, ; Araki & Schmid, ; Christie, Ford, & Blouin, ; Thériault, Moyer, & Banks, ; Thériault, Moyer, Jackson, Blouin, & Banks, ). Similarly, in Muskellunge, low levels of admixture from the same Ohio strain used in our study, was observed following intensive stocking into West Virginia streams despite their high use (White, Kohli, & Converse, ). Our results do not necessarily invoke a mechanism of negative selection or lower fitness of individuals to explain observed pattern.…”