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

摘要

We assessed predator acclimation as a technique to improve the poststocking survival of juvenile muskellunge Esox masquinongy and tiger muskellunge (muskellunge x 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.