Marine Life Center
State-of-the-Art Marine Hatchery for Oysters
A high priority for the Gulf Coast Marine Life Center is the development of infrastructure for and production of shellfish seed for enhancement and restoration. The GCMLC plans to produce two bivalve mollusc species, the Eastern oyster (Crassostrea virginica) and the bay scallop (Argopecten irradians), with an initial focus on oysters.
Gulf Coast Marine Life Center staff and University partners from the University of New Hampshire have extensive experience in all stages of large and complex oyster production, from hatchery to final grow-out in both private aquaculture and restoration. The Center envisions that the current partners from UNH will oversee the purchase and installation and initial operation of the hatchery and provide training to the local labor pool for continued operation. They will also participate in restoration planning and implementation in conjunction with local and regional partners and provide training and advice for entrepreneurs interested in private aquaculture.
The initial phase of oyster production is broodstock conditioning, followed by induced spawning, larval culture, setting, and nursery culture. To condition broodstock, adult oysters are fed an algal diet high in lipids and held at appropriate temperatures to insure optimal gonadal development. Thermal shock is then used to induce spawning and fertilization, this takes place in the water column. Fertilized eggs develop and progress through a series of free-swimming larval stages over a period of 14 to 20 days, depending on water temperature. These stages are referred to as the trochophore, veliger and pediveliger. The trochophore larvae feed on very small algae as they move through the water column. Trochophore larvae quickly develop into more motile veliger larvae. Toward the end of the larval cycle, pediveligers develop a foot that helps them find a suitable hard substrate on which to attach (set) and transform into small oysters. This stage is also called an “eyed larva” because of the development of a pigmented eyespot.