SETTLE · Bivalve conditioning and settlement – keys to competitive hatchery production

Hatchery production of bivalves during autumn and winter (outside natural spawning season) is a challenge, but necessary to keep market shares and ensure sufficient seed supply to European growers on a year-round basis. The SETTLE project will focus on key events during hatchery production of flat oyster (Ostrea edulis) and great scallop (Pecten maximus) which are species native to Europe. The overall objective is to foster year-round production of spat in hatcheries by controlling gonad development and maximise larval metamorphosis and settlement. Flat oyster and great scallop are both highly valued and sought-after products on the European seafood market, but insufficient numbers of high quality seed severely hamper aquaculture development of this sector. Bivalve hatcheries (SMEs) in Spain, France, Ireland and Norway are looking to increase the availability of spat and will engage RTDs in Spain, France and Norway to solve selected problems related to broodstock conditioning and larval settlement. Successful intensive production of bivalve spat depends on predictable procedures for conditioning of broodstock (manipulation with feed, light and temperature) to induce spawning, breeding period, larval rearing and settlement. To solve the seasonal problems the SETTLE project will identify environmental factors leading to successful off-season broodstock conditioning, reveal effects of conditioning and other biological processes on settlement and optimise existing culture methods and technology. By extending the hatchery production season and obtaining new knowledge and technologies the SMEs will increase the available number of flat oyster and great scallop spat. A quantity and value increase 5-10 times of today’s level is anticipated within 5-7 years. This will strengthen the competitive position of the SMEs and increase the shellfish production in Europe significantly.