Muskellunge Management: Fifty Years of Cooperation Among Anglers, Scientists, and Fisheries Biologists
Growth, Condition, and Short-Term Survival of Age-0 Muskellunge Reared Using Different Techniques [Abstract]
Michael F. Vaske, Justin A. VanDeHey, Dan J. Dembkowski, Brian Sloss, Timothy D. Simonson, and Richard A. Klett
Muskellunge Esox masquinongy are commonly reared on natural prey in hatcheries. However, this method is expensive and introduces biosecurity risks. Formulated feeds (pellets) are now being used by some agencies; however, concerns exist regarding the size and poststocking survival of pellet-reared Muskellunge compared to those reared on natural prey. Our objectives were to (1) determine if growth and condition differed between age-0 Muskellunge reared solely on natural prey (minnow only [MO]) with those reared intensively on pellets and finished extensively on minnows (minnow finished [MF]) and (2) determine relative survival of stocked Muskellunge reared using the two techniques. During 2013 and 2014, fingerling Muskellunge (N ≈ 6,000/treatment/year) were reared, marked, and stocked into 23 lakes throughout Wisconsin. Average condition was higher for MO fish (K = 0.581, 0.587) compared to MF fish (K = 0.532, 0.495), during 2013 and 2014, respectively. Minnow-only fish were significantly larger (both length and weight) at stocking than MF fish during both years. Nighttime boat electrofishing catch rates were used to asses short-term (2–6 weeks) poststocking survival. Capture rates were higher for MO fish (10.0%, 7.1%) compared to MF fish (7.3%, 4.4%) during 2013 and 2014, respectively; however, a large number of fish were captured from both treatments. These results suggest that survival was higher for MO fish. However, use of formulated feeds may be a viable option if lower poststocking survival can be offset by raising more age-0 Muskellunge for less cost than raising fish on natural prey, assuming hatcheries have enough available rearing space to accommodate higher numbers of fingerlings.