15 JULY 1999
MAINTENANCE OF BROODSTOCK, SPAWNING, AND EARLY LARVAL REARING OF PACIFIC HALIBUT, HIPPOGLOSSUS STENOLEPIS
R.R. Stickney, H.W. Liu-1999
Aquaculture, 176(1-2) : 75-86 (Current Contents)
Abstract:
A decade of research to develop techniques required for spawning and rearing Pacific halibut, Hippoglossus stenolepis, have produced a considerable amount of information on broodstock maintenance, spawning, and early life history of the species. Various problems, many of them associated with failures in the water systems employed, have frustrated attempts to produce postlarval Pacific halibut. Studies have been conducted on the environmental requirements of eggs and sac-fry and acceptable first foods have been identified. Compared with flatfishes that undergo their early life history in estuaries, H. stenolepis are extremely fragile during the first few months of life. Facilities used in egg and larval development must be designed to ensure that the fish do not bump into one another or into the walls of containers. Bacterial levels need to be minimized, so there is a requirement to maintain very clean conditions. Confounding the problems associated with Pacific halibut larval rearing is the fact that the larval period is extremely long since the fish develop at an optimum rate at low environmental temperatures (about 6 degrees C for hatching and less than 13 degrees C for larval rearing). Thyroid hormones added to the culture water appear to improve larval survival from hatching through 30 days. The presence of algae in the water at first feeding does not seem to be necessary.
(Texas A&M Univ, Sea Grant Coll Program, 1716 Briarcrest, Suite 702, Bryan, TX 77802, USA, e-mail: stickney@tamu.edu)