Hatchery Culture Of Bivalves: Fao Fisheries Technical Paper

Bivalve mollusc culture is an important and rapidly expanding sector of world aquaculture production, representing approximately 20% of this output at 14 million tonnes in 2000. The majority of production is from natural populations although increasingly stocks are approaching or have exceeded maximum sustainable yields. Enhancement of stocks through the capture and relaying of natural seed in both extensive and intensive forms of culture is common practice worldwide but the reliability of natur al recruitment can never be guaranteed and conflicts over the use of the coastal zone are becoming ever more pressing. A solution to meeting the seed requirements of the bivalve industry, applicable to the production of high unit value species such as clams, oysters and scallops, is hatchery culture. The production of seed through hatchery propagation accounts at the present time for only a small percentage of the total seed requirement but it is likely to become increasingly important as work continues to produce genetically selected strains with desirable characteristics suited to particular conditions. The advent of bivalve hatcheries was in the 1960s in Europe and the U.S. Since those early pioneering days knowledge of the biological requirements of the various species that predominate in worldwide aquaculture production and the technology by which to produce them has and continues to improve. This manual brings together the current state of knowledge in describing the v arious aspects of hatchery culture and production from acquisition of broodstock to the stage at which the seed are of sufficient size to transfer to sea-based growout.