Effect of Experience with Predators on the Behavior and Survival of Muskellunge and Tiger Muskellunge

Abstract

We assessed predator acclimation as a technique to improve the poststocking survival of juvenile muskellunge Esox masquinongy and tiger muskellunge (muskellunge × northern pike E. lucius) in laboratory, pond, and lake experiments. For all experiments, a subset of esocids was exposed to feeding largemouth bass Micropterus salmoides (250–300 mm total length). In laboratory pools containing simulated vegetation (50% of pool), we tested the vulnerability of predator-acclimated and naive muskellunge and tiger muskellunge to largemouth bass predation. For both species, survival rates were similar regardless of predator experience. Predator-acclimated esocids, however, spent more time in the vegetation, indicating that exposure to predators may alter some behaviors. We also introduced equal numbers of naive and predator-acclimated tiger muskellunge into ponds and lakes containing largemouth bass. To determine the number of surviving fish, ponds were drained after 7 d, whereas lakes were sampled immediately after stocking and throughout the fall. We found similar survival rates between naive and predator-acclimated individuals, suggesting that predator acclimation techniques that are successful with other species are not effective in reducing losses of stocked muskellunge and tiger muskellunge.

Received October 7, 2010; accepted July 14, 2011

ACKNOWLEDGMENTS

We thank J. Gramer and P. Hayes for assistance with pond and field experiments. D. Philipp, D. Soluk, C. Kolar, and D. Clapp offered critical reviews of the manuscript. We are grateful to the personnel at the Jake Wolf Memorial Fish Hatchery, especially S. Kruger, S. Stuewe, and T. Hayes, for providing esocids for laboratory and field studies and for their work at predator acclimation and marking of esocids. This project was supported in part by funds from the Federal Aid in Sport Fish Restoration Act administered through the Illinois Department of Natural Resources (IDNR) under Project F-113-R. K. Cottrell, L. Dunham, and J. Mick coordinated activities with the IDNR.