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It was with great excitement that we planned the combined meetings of Northeast Aquaculture Conference and Exposition (NACE) and the International Conference on Shellfish Restoration (ICSR) with the 33rd Milford Aquaculture Seminar (MAS). Bringing these different but complementary audiences together resulted in a meeting that combined many different aspects of fisheries restoration and aquaculture under one umbrella.Four hundred attendees including government representatives, research scientists, industry, and academia at both the university and vocational high school levels attended this event. The meeting commenced on Wednesday December 12th 2012, with over eighty people attending seven field trips to area aquaculture farms and research facilities. The formal program began on Thursday, December 13th with a plenary session including invited speakers Eric Schwabb, Acting Assistant Secretary for Conservation and Management at NOAA; Sebastian Belle, Executive Director of the Maine Aquaculture Association and Boze Hancock from the Nature Conservancy, who discussed the role of aquaculture in fisheries restoration. John Bullard, the Northeast Regional Administrator of NOAA Fisheries Service, addressed the group during the luncheon the following day. The technical papers and workshops presented were divided into 35 sessions over three days of the meeting and included topics such as the history of aquaculture, aquaculture hatchery innovations, siting and planning issues, risk management, aquaculture business management, ocean acidification, climate change, as well as aquaculture disease issues and potential remedies. Having persons present who have experienced problems and successes, along with those in manufacturing and government responsible for addressing concerns and sharing best practices, was invaluable. Discussions among this cross-section of persons who represent different aspects of aquaculture were as important as the well-presented and interesting formal papers and poster sessions. These discussions were facilitated by the many opportunities presented during the large trade show, reception, breaks, lunches, banquet and lobster bake held throughout the meeting.The importance of and need for aquaculture were made evident by all who were in attendance. We are grateful to the twenty four meeting sponsors and to all those who participated and made this such an important and memorable meeting.While oyster restoration efforts have been under way in the Chesapeake Bay for more than two decades, until recently, varying reporting methods and success criteria made it difficult to determine how much progress had been made. A goal to “Restore native oyster habitat and populations in 20 out of 35 to 40 candidate tributaries by 2025” was set in the 2010 strategy to implement the Chesapeake Bay Protection and Restoration Executive Order (signed by President Obama in 2009). This goal made it a priority for state and federal fishery managers, academics, and scientists working on oyster restoration to collaboratively define a “restored tributary” and a “restored reef” to enable them to track progress. A team of these people, led by NOAA staff, agreed on “oyster metrics” in 2011 (http//preview.tinyurl.com/8kmbdpm) that specify key metrics and target ranges for them, including tributary size, how to determine how much restorable bottom a tributary contains, how much of that restorable bottom needs to be restored, and the minimum oyster density and biomass in that restored bottom to count a tributary as restored. These new metrics enable experts to clearly see how oyster restoration efforts are working and use adaptive management to improve these efforts. These metrics serve as a tool to plan and evaluate oyster restoration consistently across the Chesapeake Bay, and the consensus-based framework used to develop them may have broader application to other restoration activities.In the past, oyster restoration in Maryland was performed primarily

Juvenile Scup Stenotomus chrysops 0.35–0.95 g were fed two different commercial diets for 9 weeks to determine growth rates. Diets were hand-distributed to four replicate groups of 45 fish, four times a day. Survival among all treatments was high (90.0–92.5%), and both diets supported good growth. After five weeks, Scup fed diet 1 were significantly greater in length and weight than fish fed diet 2. These differences remained significant throughout the rest of the study. Specific growth rate (SGR) values were 5.8%/d for fish fed diet 1 and 5.5%/d for diet 2, while feed conversion ratios (FCR) were 1.22 for diet 1 and 1.25 for diet 2. Relative growth rate (RGR) values were diet 1 = 3,689% and diet 2 = 3,077%, and daily weight gain (DWG) values were diet 1 = 0.38 g/d and diet 2 = 0.31 g/d. Scup fed diet 1 had significantly greater final live weight, total length, weight gain, SGR, RGR, and DWG measurements than did fish fed diet 2. Juvenile Scup exhibited high growth rates and low feed conversion r...

Methods for the intermediate and final grow-out of hatchery-reared bay scallops are presented. Hatchery seed 5 mm in length can be efficiently grown to 20 mm in less than 2 months in a pumped raceway system at ambient temperature and phytoplankton levels between June and October. The maximum carrying capacity of the raceways at a seawater flow of 50 liters/min is about 5 liters of scallop biomass. At 10 liters of scallops per raceway phytoplankton availability is limiting. Growth is not affected by scallop densities as high as 1.8 liters/ m2. Raceway depth does not influence growth. Suspending small scallops in a net in the raceway does not improve growth. Seed scallops stocked at various densities in lantern nets deployed in Long Island Sound grow rapidly. Densities up to 1000/m2 seem feasible and this grow-out method may prove to be cost-effective.

Juvenile bay scallops (7.2-26.4 mm) were exposed for 72 h to different concentrations of un-ionized ammonia, nitrite, or nitrate. Using the Trimmed Spearman Karber method, 50% lethal concentrations (LC(50)) and 95% confidence limits were calculated individually for each. Un-ionized ammonia concentrations above 1.0 mg N-NH(3)/L resulted in 100% scallop mortality within 72 h. The 72-h LC(50) for un-ionized ammonia was calculated at 0.43 mg N/L. At nitrite concentrations of 800 mg N/L or higher 100% mortality was observed. The 72-h LC(50) for nitrite was calculated at 345 mg N/L. Nitrate was the least toxic, with 100% mortality observed at a concentration of 5000 mg N/L. The calculated nitrate 72-h LC(50) was 4453 mg N/L. Our results indicate that un-ionized ammonia is the most lethal nitrogenous waste component to bay scallops.

Increasing amounts of atmospheric carbon dioxide (CO2) from human industrial activities are causing changes in global ocean carbonate chemistry, resulting in a reduction in pH, a process termed “ocean acidification.” It is important to determine which species are sensitive to elevated levels of CO2 because of potential impacts to ecosystems, marine resources, biodiversity, food webs, populations, and effects on economies. Previous studies with marine fish have documented that exposure to elevated levels of CO2 caused increased growth and larger otoliths in some species. This study was conducted to determine whether the elevated partial pressure of CO2 (pCO2) would have an effect on growth, otolith (ear bone) condition, survival, or the skeleton of juvenile scup, Stenotomus chrysops, a species that supports both important commercial and recreational fisheries. Elevated levels of pCO2 (1200–2600 μatm) had no statistically significant effect on growth, survival, or otolith condition after 8 weeks of rearing. Field data show that in Long Island Sound, where scup spawn, in situ levels of pCO2 are already at levels ranging from 689 to 1828 μatm due to primary productivity, microbial activity, and anthropogenic inputs. These results demonstrate that ocean acidification is not likely to cause adverse effects on the growth and survivability of every species of marine fish. X‐ray analysis of the fish revealed a slightly higher incidence of hyperossification in the vertebrae of a few scup from the highest treatments compared to fish from the control treatments. Our results show that juvenile scup are tolerant to increases in seawater pCO2, possibly due to conditions this species encounters in their naturally variable environment and their well‐developed pH control mechanisms.

Scallops were suspended subtidally in pyramid-shaped (pearl) nets in Long Island Sound, Milford, Connecticut, USA to assess effects of density and temperature at deployment on growth and survival. Juveniles as small as 4 mm were grown at densities ranging from 250 to 15 000/m 2 . There was an inverse relationship between the size of the scallops and the density that affected growth. Scallops with a mean shell height of 16–17 mm exhibited no reduction in growth when held at densities as high as 7500/m 2 . Similarly, scallops with mean shell heights of 24 to 25 mm exhibited no reduction in growth when held at densities as high as 2500/m 2 . Growth of scallops held at biovolumes as high as 1.1 l/net was not affected substantially. Survival typically exceeded 80%, and was not affected by density. Different size groups of juvenile bay scallops were deployed at ambient temperatures of 5, 11.5 and 14 °C. Survival for all but one group was greater than 80%. Deploying scallops early in the season at temperatures lower than 14 °C appears to have no advantage relative to growth.