Laboratory studies on the spawning and the early life history of Pacific halibut (Hippoglossus stenolepis)

There is a growing interest in halibut research in many countries because of its market and scientific value. The first successful spawning of Pacific halibut in captivity in the United States was conducted during February and March, 1988, and eight larvae were produced in that spawning season. Wild-caught adult halibut have been successfully maintained since 1986. They have been fed with frozen herring, squid, and shrimp. Their growth was moderate, 7.5 cm/year for immature, and 2.5 cm/year for mature fish. Both young male and female fish became mature and produced viable gametes. Low water temperature accelerated final oocyte maturation or triggered ovulation for halibut. First spawning over the past five years has occurred at temperatures below 9°C. The timing of stripping of halibut was critical as the fish have a very narrow spawning "window" for maximum egg fertilization. Halibut gametes could be maintained for 28 hours (eggs) and 14 days (sperm) with moderate fertilization success