Effect of Experience with Piscivory on Foraging Behavior and Growth of Walleyes

Abstract

We compared juvenile walleyes Stizostedion vitreum fed pellets (naive) with those fed minnows (experienced) to determine the effects of previous experience on feeding and growth. In aquarium experiments (72 L), foraging behaviors were compared for walleyes (115–180 mm total length; N = 57 each) feeding on golden shiners Notemigonus crysoleucas. Less than 60% of naive walleyes initially converted, and time to prey capture was higher than for experienced fish. In pool experiments, naive walleyes had high initial rates of conversion to minnows, but they captured and consumed fewer prey than experienced walleyes. Foraging behaviors improved with time in laboratory experiments, and naive walleyes learned to forage at rates comparable to experienced walleyes in less than 5 d. Experiments in ponds were designed to determine the effects that differences in conversion to minnows and foraging experience might have on growth and survival. Naive and experienced walleyes did not differ in growth and survival, indicating that differences in conversion rates between the two groups will not influence success in the field. Although we found no direct effects of feeding experience, indirect effects on behaviors influencing growth and survival, such as increased vulnerability to predation, must be investigated before final management recommendations can be made.