Differences in Stocking Success among Geographically Distinct Stocks of Juvenile Muskellunge in Illinois Lakes

Abstract

Muskellunge Esox masquinongy are broadly distributed across the northern United States and southern Canada. Intraspecific genetic variation suggests the existence of divergent stocks related to residence in major river drainages. Populations and stocks have likely adapted to specific environmental conditions associated with geographic location, especially latitude and the associated thermal regime. In this study, we examined differences in survival and growth among stocks of juvenile Muskellunge stocked into lakes throughout Illinois. Muskellunge from the Ohio River drainage stock, the upper Mississippi River drainage stock, and the current mixed Illinois broodstock were used for comparisons. Stocking mortality was related to temperature and was greatest for Illinois and Ohio River drainage fish that were stocked during the early fall. Mississippi River drainage fish experienced high mortality over the first summer after stocking, resulting in the lowest abundance during the second fall poststocking. In addition to low catch rates, Muskellunge from the Mississippi River drainage were significantly smaller than fish from the Illinois and Ohio River drainage stocks by the second fall. Populations from similar latitudes and climate (Illinois and Ohio) performed the best in terms of survival and growth and should be utilized in future stockings.

Received October 7, 2016; accepted March 15, 2017 Published online May 4, 2017

ACKNOWLEDGMENTS

We thank the personnel of the Kaskaskia Biological Station and the Sam Parr Biological Station for field assistance, including B. Alger, M. Anderson, M. Baldock, W. Bauer, J. Butler, R. Damstra, T. Edison, L. Einfalt, L. Freeman, J. Godbout, M. Harrington, A. Larsen, K. Mann, M. Nannini, K. Ostrand, P. Port, K. Schnake, E. Smolik, and J. Wisher. We are indebted to the IDNR Jake Wolf Memorial Fish Hatchery staff, especially T. Hayes and S. Krueger, for supplying the Muskellunge used in our study. We also thank the following for providing fingerling Muskellunge from their propagation programs: M. Hearn, Kentucky Department of Fish and Wildlife; E. Heyob and J. Navarro, Ohio Department of Natural Resources; P. Hulbert, New York State Department of Environmental Conservation; and R. Johannes, Minnesota Department of Natural Resources. Funding was provided by Federal Aid in Sport Fish Restoration Project F-151-R administered by the IDNR. L. Dunham, S. Pallo, M. Conlin, and S. Stuewe helped to coordinate activities with the IDNR Division of Fisheries. The Illinois Muskie Alliance and Muskies, Inc., at both the international level and local chapters, provided additional funding for the study. In particular, the Central Illinois Muskie Hunters, Chicagoland Muskie Hunters, Flatlanders, and Quad County Hawg Hunters chapters provided support. We appreciate Lawrence Eslinger and two anonymous reviewers whose comments greatly improved the manuscript.