The bay scallop (Argopecten irradians (Lamark)) is an Atlantic marine bivalve found along most of the coastal United States from Maine to Florida, as well as the Gulf of Mexico. Bay scallops have historically supported a large commercial fishery in the United States since the late 1800’s, with the largest operations existing along the northeastern coastal United States, but has been in decline since the 1980’s. The decline of the wild harvest commercial fishery has led to an increased interest in optimizing bay scallop aquaculture. Improving culturing methods will increase the viability of bay scallops as a potential crop for current and future shellfish farmers. A current obstacle impeding the success of bay scallop aquaculture is the prevalence of mud blister worms and pea crabs, which are known macroparasites of shellfish. The research being conducted during the overwintering and year two grow-out phase are investigating techniques to mitigate the detrimental effects of macroparasites on bay scallops. Results from the study will help guide farmers towards successful culturing methods that yield the healthiest bay scallop crop in year two.
1. Determine if Netminder antifouling paint reduces macroparasite prevalence during the overwintering phase. (Overwintering Experiment)
2. Indentify if lantern nets and/or bottom cages are more successful in reducing macroparasite prevalence in bay scallops during the year two grow-out phase, and if the use of Netminder further reduces prevalence. (Year two grow-out Experiment)
In December 2017, bottom condo cages with 5/8″ ADPI bags, both Netminder coated and non-coated, were stocked at a 20 scallops/ft2 with naïve bay scallops. 20 scallops were shucked prior to deployment establish that the scallop population for the experiment were naïve. All shucked scallops were free of parasites. Additionally, shell height and dried visceral weight were recorded to establish a base condition index. Condition index is the ratio of dried visceral meat weight relative to shell height. Having a base condition index of the naïve scallops upon deployment will act as a control. Scallop pulled each month will also be assessed for condition index and parasite prevalence. Condition index comparisons of infected scallops compared to the controls will allow for the effect of the parasites on the fitness of the scallops to be assessed. Additionally, the timing of parasite invasion will also be assessed via the data obtained from monthly sampling.
During the year two grow out phase, hanging lantern nets and bottom cages, either Netminder coated or non-coated, will be stocked at 20 scallops/ ft2 with naïve bay scallops. Shell height, meat weight, survival, and macroparasite prevalence will be assessed to quantify product health and market viability at the end of a 5 month period.
Gear was deployed in December, 2017. No data, other than control data, has been obtained yet.
Due to lack of data, since the project has just begun, no research conclusions can be made at this time.
Education & Outreach Activities and Participation Summary
Once research has been conducted, findings on successful macroparasite mitigation techniques in bay scallop aquaculture will be made accessible to the public. Material will be presented at conferences and any significant findings will be included in publication format.