A seeding experiment of juvenile great scallops (Pecten maximus (L.)) off the Island of Jersey

In 1995, landings of Great scallops, Pecten maximus (L.) increased dramatically in Jersey from around one tonne in the previous year, to 66 tonnes and this continues to rise. This was caused by the introduction of scallop diving permits and diversification of the fishing fleet. Due to this increase in effort it was decided that the feasibility of ranching one-year-old juvenile scallops should be investigated. 100,000 scallops were purchased from Ireland and seeded in specifically selected coastal sites. The scallops grew from 22.8 mm shell length and 1.17 grams to 57.6 mm and 23.2 grams in the first six months after seeding, and to 93.3 mm and 88.9 grams during the subsequent 12 months. Growth rate slowed considerably during winter months. Given these growth rates the scallops will reach market size in three years from settlement, less than the 4, 5 and 6 years taken in Guernsey, the Eastern Channel and the offshore Irish Sea respectively. Although growth rates are not unique and are comparable with other inshore sites in the UK, they are significant for scallop farming in Jersey waters. Mortality following re-seeding and predation rates by crab and starfish appears to be lower than reported by other workers. However this has not yet been quantified.