Practical Hatchery Procedures for Alewives and Blueback Herring

The release of hatchery-reared larvae and juveniles is one tool available for stock enhancement of depleted fish populations.  To develop practical hatchery procedures for river herring, a number of experiments were conducted with spawning adults, larvae and juvenile fish.  Spawning and anesthesia procedures were developed for wild-caught fish of both species, and successful, volitional hybridization was demonstrated.  Embryo incubation and egg disinfection experiments were conducted and feeding regimes and growth rates were established for larval fish. Salinity tolerance of embryos, larvae and juveniles was assessed and juvenile fish were captive-reared under different environmental conditions for over a year. These experiments increased our understanding of the environmental and social influences on river herring spawning and survival during their early their life stages.