Recruitment Failure of Walleye in
Norris Reservoir, Tennessee
Christopher J. OBara and Christopher L. Centracchio,
Center for the Management, Utilization and Protection of Water Resources, Tennessee
Technological University, P.O. Box 5033, Cookeville, Tennessee 38505; Voice 931-372-3753;
FAX 931-372-6346; E-Mail cobara@tntech.edu, clc5027@tntech.edu
Douglas Peterson, Tennessee Wildlife Resources Agency, 6032
Andrew Johnson Highway, Talbott, Tennessee 37877; Voice 432-587-7037; FAX 432-587-7057;
E-Mail dpeterson@mail.state.tn.us
Keywords: walleye, recruitment failure, alewife
Walleye Stizostedion vitreum are an important
sportfish in many southeastern reservoirs and large rivers. Norris Reservoir, a large
tributary reservoir of the Tennessee River, was historically noted for both riverine and
reservoir spawning populations of walleye. Horizontal experimental gill nets have been
employed since 1993 to evaluate the reservoir-residing walleye population in Norris
Reservoir and to evaluate possible effects of recently introduced alewife Alosa
pseudoharengus on pelagic fish populations. Sampling was conducted monthly from May
through November. Larval fish collections were taken in late-winter and early spring in
1996 and 1997 throughout the system. No larval walleye were collected in either 1996 and
1997, although several other species were noted. Age-0 walleye CPUE (no./net-night) were
not significantly different in the Fall 1993 and 1994. No Age-0 walleye have been
collected since the Fall 1994. Age-1 CPUE were not significantly different from 1993
through 1995, but no Age-1 walleye have been collected in 1995, 1996 and 1997. Angler
creel surveys also indicate that reduced recruitment to the fishery has occurred and the
harvest is currently dominated by larger and older individuals. Consequently, it appears
walleye have not successfully reproduced in Norris Reservoir since 1994. Concurrent with
the reproductive failure of walleye has been a significant increase in the abundance of
alewife. Alewife CPUE has increased significantly since 1994 and are now the most abundant
clupeid inhabiting the reservoir.
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