Evaluation of cannibalism during hatchery rearing of tiger muskellunge crosses

Abstract

Abstract Objective Juvenile tiger muskellunge (Northern Pike Esox lucius × Muskellunge E. masquinongy ) are cannibalistic, which can lead to a substantial reduction in yields within an intensive culture environment. Utah hatcheries have traditionally raised the female Northern Pike × male Muskellunge cross, and hatchery managers are reluctant to raise the female Muskellunge × male Northern Pike due to a perceived difference (increase) in cannibalism rates when rearing this cross. Methods We raised both crosses in replicated microcosms to evaluate the differential cannibalism between them. All rearing conditions were consistent among treatments and replicates. We evaluated weekly cannibalism using generalized linear regression models. Result After 6 weeks, we found that the female Muskellunge × male Northern Pike cross offspring were significantly more cannibalistic than juveniles from the female Northern Pike × male Muskellunge cross, with total cannibalism across the 6‐week period estimated at 27% and 5.6%, respectively. Conclusion We documented a previously unreported difference in tiger muskellunge cross cannibalism rates. Choosing the female Northern Pike × male Muskellunge cross could substantially increase survival of juvenile tiger muskellunge in aquaculture facilities.