Previous shellfish models have, in general, been calibrated for 1 location, unable to simulate growth across habitats that contrast in seston abundance and composition, as may vary between turbid, eutrophic and oligotrophic waters. Here, we describe the generic shellfish model ShellSIM, demonstrating how a common parameter set simulates growth effectively on calibration in the mussel Mytilus edulis and oyster Crassostrea gigas during normal culture across 9 different locations in Europe and China. Options enable the user to assess the relative values of chlorophyll a (CHL, measured in micrograms per liter), total particulate organic matter (POM; measured in milligrams per liter), and total particulate organic carbon (POC; measured in milligrams per liter) as codescriptors of the food available at separate locations. Using CHL as the sole proxy for available organics, together with an average carbon-to-CHL ratio of 50, growth in both M. edulis and C. gigas was predicted accurately at only 5 locations, primarily those with relatively low average food availability. In contrast, more than 74% of the observed variance in growth was predicted across all 9 locations in each species on inclusion of dynamic relations defining ingestion and absorption of both CHL-rich and all remaining organic matter such as may include bacteria, protozoans, colloids, and/or detritus, thereby helping to account for temporal and spatial changes in dietary composition. The energy content of the remaining organic matter (measured in Joules per milligram) ranged seasonally across all sites from about 2–25 J/mg, and could be predicted with growth from the relative abundance of CHL and POM alone, proving a viable alternative to more technically demanding measures of POC. Fractional contributions of the remaining organic matter to the energy absorbed in both species at each location ranged from less than about 0.4 during the spring to more than 0.8 from late autumn, in negative relation with CHL, thus helping to offset tissue wasting during winter months. We acknowledge model uncertainties, emphasizing the need to balance practicality and affordability against required accuracies. Last, we describe how the generic and multi-site capabilities afforded by ShellSIM, together with real-time outputs ready for integrated modeling of how shellfish influence ecosystem properties and processes, are saving time and resources across a variety of applications.

Biofouling ascidians represent a serious and costly problem for aquaculture. Although the subject of intensive study for the past decade, little is still known about the timing, intensity, and duration of ascidian settlement, especially in coastal Maine. To assess ascidian settlement, PVC panels were deployed in the Damariscotta River, Maine, on a weekly basis during the summers of 2007 and 2008. Long-term fouling panels were deployed from June to October 2007 to assess the development of mature fouling communities. Settlement of fouling organisms largely occurred during 2 seasonal phases. Early summer (May to July) was dominated by settlement of hydroids and bivalve molluscs; late summer and early fall (August to September) was dominated by ascidian settlement. Overall, ascidians accounted for ∼50–80% of total settlement. The solitary ascidian Ciona intestinalis dominated mature fouling panels, but had low and intermittent settlement levels. The invasive colonial ascidian Didemnum vexillum settled later in the year (starting at the end of July) than other taxa. Specific knowledge of settling patterns of biofouling organisms may provide growers with a means of determining opportune times for deployment of gear to avoid excess fouling.

Mussels (Mytilus spp.) are used frequently in biological effects studies and biomonitoring programs either as transplanted groups or native populations. However, as a result of the similarities in the external morphology of Mytilus, which are influenced by environmental factors, visual identification is often never certain. Because differences in contaminant bioaccumulation and biomarker responses may occur among the 3 mussel species Mytilus edulis, Mytilus trossulus, and Mytilus galloprovincialis, bias in biological effects studies and biomonitoring programs is likely. In the current study, mussels were collected from strategic locations along the 25,000-km Norwegian coastline and identified to species by polymerase chain reaction amplification of gill tissue DNA. Specific primers were used to amplify the Glu gene (polyphenolic adhesive protein), which has been validated previously to identify the different Mytilus species. The amplified products were electrophoresed, showing specific bands for M. edulis (180 bp), M. trossulus (168 bp), and M. galloprovincialis (126 bp), with the presence of 2 bands suggesting Mytilus hybrids. The results identified the presence of all 3 Mytilus species in a patchy distribution around the Norwegian coast, with the Mediterranean species M. galloprovincialis located up to 60°N. The implications of this situation for biomonitoring programs and exposure studies are discussed.

The pearl oyster Pinctada fucata martensii is the dominant species for production of marine pearls in China. To explore the relative contributions of donor and host oysters to nacre deposition in cultured pearls, donors of 3 size groups—large, medium, and small—and hosts of different sizes were used for pearl production. Resulting pearls were numbered to allow tracing of donor and host. Results showed that pearls developed from the 3 different groups of donors showed no significant difference in diameter, weight, and nacre thickness; however pearls cultured in different-size hosts differed significantly with regard to these parameters. Specifically, pearl size, weight, and nacre thickness correlated positively with the size and weight of host oysters, with coefficients ranging from 0.22–0.34. It is suggested that in selection of host oysters used for pearl production, if other conditions are equal, those of larger size and weight are more preferable, for they will presumably produce pearls of larger size and nacre thickness.

Estuaries are characterized by large amounts of nutrient loads, wide intertidal sand flats, and a high biomass of buried filter-feeding bivalves. A field study was designed to determine the role of the buried bivalves in the estuarine nutrient cycle. The biodeposition, respiration, and excretion rates of a dominant surf clam (Mactra veneriformis) in the Shuangtaizi estuary, Bohai Sea of China, were determined seasonally using a sediment trap and a closed respirator. The carbon (C), nitrogen (N), and phosphorus (P) budgets of M. veneriformis for 4 seasons were also modeled. The results showed an obvious seasonality in the physiological rates for the studied clam. The lowest biodeposition rates occurred in winter (0.008 g/individual/day), whereas the highest appeared in summer (0.309 g/individual/day), and were mainly attributed to the effects of water temperature and seston concentration. The maximum respiration rate occurred in summer (30.65 mg/individual/day), whereas the minimum occurred in winter (0.54 mg/individual/day). The excretion rates for ammonium and phosphate also fluctuated seasonally, with the highest value in spring and the lowest in winter. The results also showed that the C, N, and P budgets were in the following order: C loss from respiration > C loss from fecal production > C loss from growth; N loss from growth >N loss from fecal production > N loss from excretion; and P loss from growth > P loss from fecal production > P from excretion. The C, N, and P budgets illustrate that the M. veneriformis population used relatively more N and P than C for growth, and efficiently transferred the pelagic primary production to a higher trophic level. This study suggests that M. veneriformis may play a key role in the nutrient cycle of the estuarine ecosystem and should be considered an important component of the ecology of estuaries.

The clam Anadara inaequivalvis (Bruguière) is a bivalve mollusc now populating several areas of the Mediterranean Sea seafloor where it competes with other molluscs harvested as food. In fact, even though Anadara inaequivalvis has valuable nutritional properties, it has no commercial value in European countries. The aim of this study was to evaluate quantitatively and qualitatively fatty acid content in this bivalve mollusc and to compare 11 extraction methods: conventional procedures such as Folch, Bligh and Dyer, and Soxhlet with different solvents, as well as accelerated solvent extraction (ASE) and methods using low-toxicity solvents as substitutes for chloroform (CHCl₃) and methanol (MeOH). The best method was ASE CHCl₃-MeOH, affording yields of total lipids, total fatty acids, and polyunsaturated fatty acids (PUFAs) significantly higher than any other method. The estimated range of total lipids was 2.29%–6.99% (on the dry sample), and the range of fatty acids was 0.74%–1.78%. Yields of polyunsaturated fatty acids (PUFAs) ranged from 0.10% to 0.40%. The solvent mixture hexane—isopropanol as substitute for CHCl₃-MeOH did not afford good results. PUFAs were 22.5% in the total fatty acids and the ratio between PUFAs n-3 and PUFA n-6 was 2.74:1.

Metal concentrations were measured in seawater in the Piedras River estuary (southwest Spain) for 15 mo during 2005 to 2006. A significant sinusoidal seasonal variation of Cu and Zn was observed. The Cu levels were up to 30 µg/L. Effects of Cu concentrations, ranging from 0–100 µg/L, and exposure times of 48 h, 72 h, and 96 h on both mortality and a lethal concentration (LC50) of Venerupis decussata (Linnaeus 1758) larvae were studied. Larval mortality was 100% 96 h after exposure to 100 µg Cu/L, and mobility decreased after exposure to 100 µg Cu/L for 48 h or longer. Lethal concentrations for 48 h, 72 h, and 96 h were set at 190, 97, and 49 µg Cu/L, respectively. Results indicated that Cu concentrations recorded in Piedras River estuary (up to 30 µg/L) did not affect 96-h larval development of V. decussata.

The diet of the keyhole limpet Megathura crenulata was determined from stomach contents of 119 specimens collected from 3 rocky reefs on the west coast of the Baja California Peninsula, Mexico, in July and November 2006 and March 2007. Limpet stomachs contained 78 taxa, including filamentous cyanobacteria, diatoms, brown and red algae, marine seagrass, foraminifera, hydrozoans, bryozoans, nematodes, bivalves, gastropods, crustaceans, and tunicates. The main food items (>10% index of relative importance) consumed by the limpet were a tunicate; red algae of the genera Callophyllis, Coralina, Cryptopleura, Nienburgia, Pterosiphonia, and Rhodymenia; the brown algae Cystoseira osmundacea; the hydrozoan Eudendrium; and the bryozoan Crisia. Despite the differences in composition and abundance of the main items among sites and dates, the food groups of tunicates and algae account for more than 80% index of relative importance of the diet. The trophic niche breadth (Levin's index) was 0.52 ± 0.20. Our findings show that M. crenulata is an omnivorous gastropod that feeds primarily on tunicates and red algae, although it consumes other algae and invertebrates associated with their main food source.

Local abundance was estimated and distribution determined for selected large gastropod species based on observations made during underwater visual surveys at 10 sites along the Gulf coast of Florida each summer from 2009 through 2012. The total number of tulip snails (Fasciolaria spp., including the true tulip, Fasciolaria tulipa, and banded tulip, Fasciolaria lilium), lightning whelk (Busycon sinistrum), and horse conch (Triplofusus giganteus) were counted at 190 stations (each 600 m²) each year in shallow-water seagrass beds. Tulip snails were observed most frequently, with a mean density of 1.93 ± 3.56 snails/ 600 m², with substantially fewer lightning whelks (0.29 ± 1.04/600 m²) and horse conchs (0.10 ± 0.37/600 m²) observed. Horse conchs were distributed more evenly across the 4 Gulf coast regions studied: Panhandle, Big Bend, Nature Coast, and South. Tulip snails were most abundant in the Panhandle and the South, whereas lightning whelks were found predominantly in the South. Snail counts peaked in 2010 and were greatest at the Pine Island Sound site, although mean density was greatest in Sarasota Bay (2.2 snails/600 m²). Snails were observed most frequently at the St. Joseph Bay site, where they were present at 74 of the 80 stations surveyed. Statewide commercial fisheries landings data were examined for years 1994 through 2011 and totaled 130,710 true tulip snails (banded tulip snails were not included), 72,230 lightning whelks, and 33,087 horse conchs. The total number landed of both lightning whelks and horse conchs was greater on the west coast of Florida, whereas the total number of true tulip snails landed was greater on the east coast.

Restocking and potential stock enhancement of natural abalone stocks by seeding hatchery-reared juvenile abalone into suitable habitat is currently being investigated or implemented in a number of countries, including Japan, Australia, New Zealand, Mexico, and South Africa. A series of experiments has been conducted to investigate the feasibility and development of the technology required to do this in the Sultanate of Oman. Wild seed were collected between Mirbat and Ras Atian on the Dhofar coast and kept in a hatchery for 7 wk. Qualitative and observational data were used to develop seeding site selection criteria and a seeding density of 10 juveniles/m². The juveniles were relocated and seeded in 18 different sites spread over a distance of 72 km. Sites selected with an abundance of boulders with a diameter of less than 50 cm yielded the highest recovery rates. Different categories of habitat availability and selection by seeded juveniles for specific habitat categories varied significantly among sites, which was reflected in the range of recovery rates. Boulder habitats less than 50 cm in diameter supported the most recovered juveniles (P = 0.002 and P = 0.005). Survival rates over a period of 30, 60, and 90 days ranged from 0%–80% and proved highly site specific (P = 0.04). A positive correlation was found between average seed size and increased recovery rates (P = 0.015, R² = 0.25). Dispersal was limited in sites with high recovery rates. Site selection was shown to be vital. A simple seeding mechanism comprising a PVC tube proves successful as an alternative to seeding by hand.

The genus Octopus occurs in tropical and temperate oceanic waters throughout the world, and currently includes 112 species, although the phylogenetic relationships among the different taxa are still poorly understood. The cosmopolitan Octopus vulgaris is one of the most widely analyzed cephalopods in genetic studies, primarily because of its ample range and the problems associated with the morphological identification of specimens, which indicate the possible existence of a species complex with a worldwide distribution. Two large-bodied octopus species—O. vulgaris and Octopus insularis—are found in the western South Atlantic. The limits of the geographical range of the O. insularis are still unclear. The current study is based on a phylogeographic analysis of the 2 species in the South Atlantic, with the objective of confirming their monophyletic status and the limits of their geographical distribution in this region. The analyses were based on the mitochondrial genes 16S rDNA and Cytochrome Oxidase subunit I (COI). The topologies generated for both genes confirmed the monophyletíc status of the 2 species. In the case of O. vulgaris, it was possible to confirm the monophyletic status of the specimens from this region relative to those of other areas around the world, although 3 distinct haplogroups were clearly differentiated, corresponding to the Americas, Europe and Africa, and Asia. The differentiation among these 3 groups may be determined by the limitations of the dispersal of paralarvae among continents. Further studies are needed to confirm the possible occurrence of distinct groups in the western South Atlantic, as well as the influence of oceanic currents on the phylogeographical distribution of O. vulgaris on the Brazilian coast.

Specimens of the uncommon luminous flying squid Eucleoteuthis luminosa were collected off the west coast of the Baja California peninsula during 2004, 2005, and 2008. The morphology and morphometry of adults, juveniles, and paralarvae of this species, as well as the oceanographic conditions during specimen sampling are described. Adults and 1 juvenile were collected in surface waters both day (20.5°C sea surface temperature (SST); 0.15 mg/m³ and 0.55 mg/m³ chlorophyll-a (Chl-a), respectively) and night (24°C SST, 0.08 mg/m³ Chl-a). Paralarvae were collected between the surface and ∼150 m in depth mainly during the night (21 ± 0.7°C SST, 0.15 ± 0.05 mg/m³ Chl-a). This unusual record confirms the presence of E. luminosa off the west coast of the Baja California peninsula, Mexico, and the presence of paralarvae suggests spawning in this area.

A system and management protocol was developed that maintained large numbers of paralarval longfin squid in a laboratory for 18–44 days. The system included a 200-L conical tank, an inflow pipe with a 1-µm filter, an aeration ring, and a centered outflow standpipe with a 150-µm mesh outflow filter. Cleaning and maintenance protocols involved siphoning tanks, periodic partial draining, and transfer of squid from a used tank to a clean tank. Paralarval squid were fed brine shrimp and commercial rations, which they ingested. Squid survived and grew in the system until catastrophic disruptions terminated the experiments prematurely. With suitable backups and refinement, the system design, management protocol, and feeding regime used provide a starting point to increase squid utility for research and commercial production.

In this study, the statolith microstructure of the jumbo squid Dosidicus gigas was used to determine age, individual growth, and changes in sexual maturity off the west coast of the central region of the Gulf of California during 2000 and 2002. The number of individuals sampled was 3,369 with a sex ratio of 1.8:1 (female to male). The size at first maturity (ML50%) in males varied between 46 cm and 56 cm, which was less than that seen in females (76–79 cm). The age of 251 squid was analyzed, and the growth of each sex was described by fitting the Gompertz and logistic models to the age-mantle length (ML) data. The Gompertz model best described the growth of the jumbo squid, and no significant differences were detected between sexes (ARSS, F = 0.73, P = 0.54). The parameters estimated for the combined data were ML∞ = 143.3 cm and g (growth coefficient at inflection point) = 0.004/y and t₀ (age at inflection point) = 259.5 days. From the hatch date frequency distribution, a permanent incorporation of small individuals (ML, <55 cm) was identified in the fishing zone with 2 maximum values, one in May and another in November, suggesting that there are at least 2 cohorts in the population.

Small (∼15 mm) and large (∼30 mm) calcein-marked bay scallops, Argopecten irradians, held for 2, 4, and 6 wk in the laboratory under natural illumination and conditions of high and low flow rates deposited significantly more striae on the surface of the left (dark) shell valve compared with the right (light) shell valve. Small scallops deposited an average of 0.55 stria per day, 0.42 stria per day, and 0.34 stria per day, respectively, during the 2-, 4-, and 6-wk experiments, whereas large scallops had a lower frequency of stria formation (0.20 stria per day, 0.18 stria per day, and 0.17 stria per day, respectively). Striae deposition and interstria distance were highly variable among small A. irradians. No relationship in interstria distance was obvious in A. irradians that deposited the same number of striae during 6 wk (0.45 striae per day) and held under conditions of high flow rate, indicating that stria formation is not synchronous with changes in the environment. Our results demonstrate unequivocally that in, A. irradians, stria formation is nondaily and is related to shell growth rate. The largest and oldest scallops (∼30 mm and 1.4 y old) formed striae at a rate of 0.17–0.2 stria per day whereas smaller and younger fast-growing A. irradians formed between 0.34 striae per day and 0.55 stria per day—clear evidence of nondaily and nonrhythmic deposition of striae in this pectinid species. Thus, striae cannot be used as a chronological marker with which environmental conditions can be compared.

Natural beds and cultures of the scallop Argopecten purpuratus are exposed to hypoxia periodically because they are located near upwelling zones. We evaluated the effects of environmental hypoxia on juvenile and adult scallops' escape responses and recovery capacities using 3 different hypoxic cycle (i.e., a gradual decrease and increase of dissolved oxygen) trials. Trials 1 and 2 consisted of single (1-day) hypoxic cycles; trial 3 included exposure to several consecutive daily hypoxic cycles over 7 days, which occurs in the natural environment. Trial 1 evaluated the combined effects of energy demands from escape responses and metabolism on escape responses. during environmental hypoxia. Trial 2 evaluated only the effect of environmental hypoxia on the escape responses. Before and after the hypoxic cycles, the scallops were exposed to their main predator, the sea star Meyenaster gelatinosus. We evaluated 6 indicators of the scallops' escape response: reaction time, the total number of claps, duration of the clapping response until exhaustion, clapping speed, the proportion of claps, and recovery clapping rate after a recuperation of 5 min or 10 min (for juveniles and adults, respectively). The combined effect of functional and environmental hypoxia (trial 1) affected both juvenile and adult escape responses, with a reduction in their number of claps (15% and 25%, respectively), the clapping rate in juveniles (17%), and the clapping time in adults (19%). However, environmental hypoxia alone (trial 2) affected juvenile escape responses only, with a reduction in their number of claps (18%) and clapping rate (17%). After hypoxic exposure in trial 3, adults only showed a reduced escape capacity (clap number and clapping time of 16% and 17%, respectively), although both adult and juvenile scallops had a reduced capacity to recuperate their initial clap number (18% and 23%, respectively) and clapping rate (21% and 17%, respectively). Recovery capacity was associated with a strong reduction in phasic muscle carbohydrates during this period. Overall, hypoxia reduced the escape capacity of A. purpuratus, which may implicate a higher vulnerability to predation (for natural populations) and a decreased physiological status to support other stress factors (for cultured or natural populations).

Hybrids between Crassostrea hongkongensis and Crassostrea ariakensis were produced to evaluate their aquaculture potential in northern China. Fertilization success was asymmetrical; C. hongkongensis eggs can be fertilized by C. ariakensis sperm, but not vice versa. Molecular genetics analysis revealed that hybrid progeny were true hybrids. Larval growth of hybrids was intermediate between C. hongkongensis and C. ariakensis, whereas larval survival in hybrid families ranged from 0.3–37%. The progeny of C. hongkongensis did not survive during an outdoor overwinter phase, whereas hybrids and C. ariakensis showed similar survival rates (>72%). Mean shell height of hybrid adults at day 360 was 54% larger than that of C. hongkongensis adults, and was 25% larger than that of C. ariakensis adults. Morphology of the hybrid adult was similar to that of C. hongkongensis. On the basis of high overwinter survival and faster growth than either parental species, we suggest that the hybrid between C. hongkongensis and C. ariakensis may substitute for C. hongkongensis as a cultured species in northern China.

Oysters, like the vast majority of sessile marine invertebrates, shed sperm and eggs into the water column where fertilization subsequently occurs. The fate of the gametes depends on their passive movements at various scales in a high-viscosity environment, the longevity of the sperm's ability to affect oriented movement, the rate of sperm movement toward the egg target, and the ability of sperm to effect fertilization. Oyster sperm swim in a helical pattern with a mean forward progression velocity of 0.057 ± 0.010 mm/sec (SE; n = 25) with the 95 percentile range extending from 0.036–0.078 mm/sec, a value comparable with that reported for echinoderm sperm.

Female broodstock of Pacific oyster (Crassostrea gigas) were conditioned using different diets to determine the effect of diet on oocyte cryopreservation success. Oocyte biochemical composition, fatty acid profile, and fertilization success before and after cryopreservation were determined. Broodstock were conditioned in 2 stages: a cold preconditioning stage during which animals were either starved or fed live microalgae, and a warm conditioning stage during which animals were again either starved or fed live microalgae, AlgaMac-2000, or a mixture of corn and rice flour. Overall, oysters that were fed microalgae during cold preconditioning produced oocytes with significantly more lipid than oysters that were starved. Similarly, those that were fed during warm conditioning produced oocytes with more lipid than starved oysters, regardless of diet. There was no effect of conditioning regime on the level of polyunsaturated fatty acids (PUFAs) in the polar lipid fraction. However, oysters that were starved or fed AlgaMac-2000 during warm conditioning had higher PUFA levels than oysters fed microalgae or flour. Broodstock conditioning regime had no effect on the fertilization success of oocytes prior to cryopreservation, but those that were fed during cold preconditioning produced oocytes that had significantly higher fertilization success after thawing.

Bacterial pathogens, including several Vibrio spp. and Roseovarius crassostreae, cause severe mortality of larval and juvenile eastern oysters. The introduction of beneficial bacterial isolates in oyster hatcheries and nurseries for the biocontrol of bacterial diseases is a good alternative to the use of antibiotics. The goal of this study was to screen and characterize marine bacterial isolates as potential agents to prevent larval and juvenile mortality by the oyster pathogens Vibrio tubiashii and R. crassostreae. Screening of bacterial isolates from Rhode Island marine organisms and environment using agar-based assay methods for detection of antimicrobial activity against oyster pathogens led to the isolation of candidate probionts Phaeobacter sp. S4 and Bacillus pumilus RI06-95. Pretreatment of larval and juvenile oysters for 24 h with 10²–10⁶ cfu/mL Phaeobacter sp. S4 or B. pumilus RI06-95 protected larval oysters against mortality resulting from challenge with R. crassostreae and V. tubiashii (relative percent survival (RPS) range, 9%–56%). These probiotics also protected juvenile oysters against challenge with V. tubiashii (RPS, 37%–50%). Probiotic isolates had no negative impact on oyster survival. Protection conferred to larvae against bacterial challenge was short-lived, lasting for only 24 h after removal of the probiotics from the incubation water. These results suggest the potential of marine bacterial isolates Phaeobacter sp. S4 and B. pumilus RI06-95 to serve as biocontrol agents to reduce the impact of bacterial pathogens in the culture of Crassostrea virginica.

The eastern oyster Crassostrea virginica has a remarkable ability to withstand low oxygen conditions; however, many of the biochemical mechanisms by which that tolerance is accomplished remain poorly understood. In addition, little is known about hypoxia tolerances and adaptations of the Asian oyster Crassostrea ariakensis. By comparing these closely related species, we may learn more about the physiological mechanisms responsible for the hypoxia tolerance of C. virginica. We assessed the time to mortality and gaping responses in both species during hypoxia. Adult C. ariakensis died earlier than C. virginica and gaped more often and wider than C. virginica. Gaping by either species was associated with acidification of the ambient seawater. We also compared the hemolymph pH of emersed and clamped C. virginica and C. ariakensis between 0 h and 24 h. In both species, hemolymph pH declined over time, and C. ariakensis hemolymph became significantly more acidic throughout the study period than that of C. virginica. The infection levels of Perkinsus marinus observed in our samples were not correlated with hemolymph pH changes in either species. Our findings demonstrate fundamental differences in survival and suggest important physiological differences exist between these species.

We monitored cage-based populations of the eastern oyster Crassostrea virginica in coastal waters of New York Harbor in 2 phases of sampling, 1 with localities spread out over the New York—New Jersey Harbor area (started 2008) and another with 3 localities within Jamaica Bay (started 2010), all impacted by high nitrogen input, low dissolved oxygen, but over a water quality gradient. Patterns of growth, mortality, condition, and disease were compared with a clean—water site in Shelter Island, NY, sampled in parallel with both sampling phases. In both studies, oyster mortality in the urban sites increased dramatically during and after the second summer growth season. Mortality also increased at the same time period at the cleanwater site, but to a much smaller degree. One instance of high mortality in the Lower Hudson was caused by MSX; but, otherwise, no known diseases were identified as the main cause of the sudden mortality increases. Our results suggest that a general effect of reduced water quality had a cumulative effect on the New York Harbor-emplaced oysters, which culminated in high mortality, mainly at the end of the second summer growing season. Despite the increased mortality, other factors such as soft tissue growth and reproduction were not reduced in the harbor sites relative to the clean-water control site. The vulnerability of oysters grown in impacted waters may have to be factored in attempts to restore oysters to impacted harbor waters.

Cryopreservation can preserve genetic materials in perpetuity and can be applied to oyster culture for breeding programs. Protocols exist for sperm cryopreservation in the eastern oyster Crassostrea virginica, but nonlethal sample collection is needed for valuable individuals, such as tetraploids, or specific lines. The goal of this study was to develop nonlethal methods for sperm collection in the eastern oyster. The objectives were (1) to evaluate natural spawning as a collection method, (2) to evaluate anesthesia methods to induce shell opening for biopsy, (3) to evaluate mechanical notching for biopsy, and (4) to verify notching combined with biopsy for collection and cryopreservation. Five males (of 60 oysters) spawned naturally after 7 h, with an average sperm concentration of 1.9 ± 1.0 × 10³ cells/mL (in 2 L seawater). No oysters (n = 30) responded by opening during 36 h of treatment with 5% Dead Sea salt (containing 33.3% MgCl₂), and 22 oysters (of 30) opened during the 36-h treatment with 5% Epson salt (MgSO₄). Sperm collected by biopsy had fresh motility of 3%–80% and postthaw motility of 1%–5%; sperm production was 4.5 × 10⁵ to 2.3 × 10⁸ cells per male. Mechanical notching did not cause mortality to oysters (n = 20). After notching and biopsy with 18-G and 20-G needles, survival was 80% (16 of 20 for each). Sperm production was 5.42 × 10⁷ cells by 18-G needle (n = 8) with fresh motility of 16 ± 12% and postthaw motility of 3 ± 2%, and 1.35 × 108 cells by 20-G needle (n = 9) with fresh motility of 21 ± 20% and postthaw motility of 5 ± 4%. No differences were observed between samples biopsied with the 2 needle sizes (P ≥ 0.074). To verify notching and biopsy for nonlethal sperm collection, a total of 39 oysters were sampled to obtain 20 males, which averaged 99.48 ± 23.17 g total weight, 74.1 ± 6.0 mm shell height, and 60.9 ± 7.2 mm shell length. The sperm production was 3.6 ± 2.1 × 108 cells per male. Biopsied sperm showed 23 ± 12% fresh motility, 13 ± 6% postequilibration motility (after equilibration with 10% of DMSO for 30–60 min before freezing), and 6 ± 4% postthaw motility. Flow cytometry analysis indicated an average of 84 ± 4% of cells with intact plasma membranes for fresh sperm, and 59 ± 9% for postthaw sperm. Fertilization by thawed sperm averaged 20 ± 22% (from 1%–87%). No significant differences were observed between the biopsied samples and the dissected samples (lethal collection) for fresh motility (P = 0.550), postequilibration motility (P = 1.000), postthaw motility (P = 0.101), fresh membrane integrity (P = 1.000), or postthaw membrane integrity (P = 1.000), but a difference was observed in fertilization (P = 0.039; biopsied samples, 20 ± 22%; dissected samples, 68 ± 40%). Overall, this study developed notching combined with biopsy for sperm collection and cryopreservation in Eastern oysters that can be applied to valuable individuals and breeding programs.

Cupped oysters are common and abundant along the coast of China, but their classification has been uncertain. In previous studies, we classified 2 of the cupped oysters into 2 subspecies: Crassostrea gigas gigas from the northern coast of China and Crassostrea gigas angulata from the southern coast of China. There is another small cupped oyster that seems different from these 2 species and resembles Crassostrea sikamea Amemiya 1928. To determine the taxonomic status of this oyster and its distribution, we collected wild oysters from 12 sites in China, identified putative C. sikamea with genetic markers, and compared them with known C. sikamea in both morphology and sequences of the mitochondrial 16S rRNA and cytochrome oxidase I gene fragments. Sequence analyses confirm classification based on genetic markers that this small cupped oyster from China is indeed C. sikamea. Our data show that C. sikamea not only occurs naturally in China, but also lives in abundance over a wide geographical distribution, ranging from Jiangsu to Guangxi, including Hainan Island. Our findings greatly extend the known distribution range of this species, and the extended distribution follows the Kuroshio and Tsushima currents, suggesting that ocean currents may play a role in shaping oyster distribution. Knowing the distribution range of C. sikamea is important to our understanding of its evolutionary history as well as fishery management and aquaculture breeding of this commercially important species.

Insufficient knowledge about physiological processes underpinning reproduction in the European flat oyster, Ostrea edulis (Linnaeus), presents a number of unique challenges when designing a large-scale selective breeding program for hatchery production. The European flat oyster is a larviparous, protandric hermaphrodite wherein asynchronous spawns and variable sex ratios can lead to loss of genetic diversity and inbreeding depression within hatchery populations as a result of disproportionate gametic contributions in mass matings. A better understanding of O. edulis physiology in relation to environmental factors has the potential to improve hatchery processes for synchronization of gametogenesis, thus increasing fertilization potential and maximizing breeding population size of broodstock. This study sought to determine whether specific conditioning procedures—notably, manipulation of temperature and photoperiod—could be used to improve synchrony of gametogenesis and predictability of sex ratios in O. edulis. Two trials of accelerated yearly variations of temperature and photoperiod were conducted to uncouple the specific role of these factors in the timing of gametogenesis and sex of gametes over several spawning cycles. Histological analysis and quantitative analysis of gonad using a gonad filling index allowed for determination of sex ratios and staging of gametogenesis. Temperature was a controlling factor, although experimental results suggested that the effects of photoperiod, uncoupled from temperature, had no effect on the timing or rate of gametogenesis, or on sex ratios during a breeding season. A better understanding of factors affecting sex ratio and synchrony in timing of gamete release will allow for improved conditioning and broodstock handling protocols in the selective breeding of O. edulis.

New Jersey manages a quota-based fishery on its Delaware Bay oyster beds. A transplant program conducted each year to augment the quota moves a small proportion of oysters from upbay beds to downbay beds where the oysters quickly improve in market quality. High mortality rates downbay warrant minimizing the number of small oysters moved downbay and retaining recruitment potential warrants limiting the quantity of cultch moved downbay. Consequently, automatic cullers are used and each transplant is monitored. An observer study was conducted during the 2011 transplant to evaluate the method of transplant monitoring. Samples taken throughout the day were compared with samples taken at the end of the day to determine if end-of-day sampling was sufficient to characterize the entire deckload. No significant difference was found between samples taken periodically during the day and end-of-day samples in 7 of 9 observed deckloads. No significant differences were found between 3 end-of-day samples taken to characterize the deckload and a larger sampling intensity of 12; thus, the current sampling intensity of 3 end-of-day samples to describe the deckload is sufficient. Because of varying gear configurations and economic incentives to load the deck quickly, we also compared cultch fractions and oyster size frequencies among boats. Representative distributions from different boats, days, and beds in the observer data set suggest that boats differing by 6–7% in cultch fraction should be identified routinely as significantly different from other boats. Significant differences were observed in oyster size frequency among boat deckloads more often than in cultch fraction. Further study is needed to determine the extent to which gear configuration affects deckload composition.

Reproductive health of the common cupped oyster Crassostrea angulata cultivated in Taiwan was estimated through histological examination and semiquantitative analysis of their gonads. Oysters were collected in 4 aquaculture sites along the western coast of Taiwan (Hsiangshan, Chiku, Beimen, and Putai), where the major sources of industrial pollution are located, and off Penghu Island in the southern part of the Taiwan Strait, a comparatively clean resort area. The oysters from Hsiangshan had the lowest gonad maturity index (GMI) and the highest index of pathological alterations (IPA; P < 0.001); greater numbers of oysters with undifferentiated gonads (30%) and a green mantle (66.7%) were also present here. Most prominent gonad pathologies were atresia of oocytes and hemocytic infiltration of gonadal tissue. Oysters from Penghu had the highest GMI and the lowest IPA, whereas oysters from Chiku, Beimen, and Putai had intermediate values. Soft tissues of oysters from Hsiangshan contained 3,761.0 ± 1,201.0 µg/g dry weight Cu, 3,761.0 ± 1,201.0 µg/g Zn, and 1.5 ± 0.06 µg/g Cd, which is about 17 times, 3 times, and 1.5 times greater than the corresponding metal concentrations in the tissues of oysters from Penghu. Gametogenesis impairment in oysters cultivated in Taiwan are likely caused by environmental pollution.

Since the 1970s, significant QX disease outbreaks have taken place in Sydney rock oyster (Saccostrea glomerata)producing estuaries in New South Wales, Australia, devastating production. Despite research efforts, there are still many gaps in our knowledge of QX disease (causative agent: Marteilia sydneyi). A better understanding of the timing and triggers of the QX infection would allow the management of oyster farms to be tailored to address the high-risk period. This study examined the extent and variability of the QX window of infection across multiple years (2005/2006 to 2008/2009) in the Hawkesbury River and characterized environmental conditions prior to, during, and after the infection window during these years. The window of QX infection onset across the years was found to be highly variable, with start times occurring between November and February, whereas the infection termination time was more defined, occurring within the first week in April, except in 2006/2007, which ceased during the last week of April. The termination of the infection window occurred during a significant decrease in water temperature (at a rate of 3.7°C/mo), with no infection occurring at water temperatures less than 21.5°C Environmental conditions were more variable at the onset of the infection window, when water temperatures showed high levels of variability among years as a result of cool freshwater inputs from rainfall events, which occur commonly at this time of year. These freshwater inputs also resulted in significant decreases in salinity levels (to at least ∼10 ppt), which may be an additional factor influencing QX disease outbreaks. Previous QX work suggested an infection period of 19 days; here, longer infection periods were observed and lasted between 8 wk and 18 wk, depending on the year.

As large, long-lived filter feeders with high clearance rates, unionid mussels are capable of altering nutrient cycling in freshwater food webs. Because the effects of mussel communities on ecosystem processes result largely from their feeding behavior, we need to understand how they sample and process particulate matter. Our objective was to determine whether measuring a suite of biochemical markers in unionid mussels, from different populations of 2 species (Amblema plicata, Actinonaias ligamentina) across a broad geographical range (4 North American rivers), would help identify their primary dietary sources. Stable isotope data were able to differentiate mussels among rivers, and sometimes species. Data on δ¹⁵N revealed that mussels fed across trophic levels but that diet varied with habitat and perhaps species. Although mussels contained the same types of fatty acids regardless of river or species, we nonetheless observed considerable variation in essential fatty acid content across rivers. Essential fatty acid profiles were dominated consistently by arachidonic acid. Source-specific fatty acid biomarkers suggested that bacterial and detrital resources might be as important as algae in many habitats. In summary, biochemical metrics differed more among rivers than between species. This suggests that mussels are either considerably adaptable in their dietary requirements or that they feed nonselectively. Understanding nutritional profiles in mussels will help restore unionid communities, which may lead to the reestablishment of their critical role as nutrient recyclers in freshwater food webs.

Integrated multi-trophic aquaculture (IMTA) aims to recapture portions of nutrient waste lost from 1 species as nutritional inputs for another. This process has the potential to augment growth of cocultured species while reducing the nutrient load from an aquaculture site. In several jurisdictions, open-water aquaculture is regulated through measures of benthic hydrogen sulfide concentrations, which is proportional to excess deposition of organic material such as feces and uneaten food. Interception, consumption, and digestion of organic portions from the fed trophic level (e.g., fish) by organic extractive species (e.g., shellfish, deposit feeders) results in “organic stripping,” with less organic material in resulting feces, thereby reducing the net organic load and benthic deposition potential. Shellfish are deployed beside fish cages in some openwater IMTA systems. In addition to the potential consumption of fish culture solids (i.e., feces, feed “fines”), natural particles (i.e., seston) will also be consumed. Consumption of seston portions by shellfish means that some suspended solids that would otherwise drift by fish cages now have the potential for redirection to the benthos as indigestible seston components, egested in shellfish feces. This raises the issue as to what dietary proportion of fish culture solids, consumed by extractive species, results in an increase or reduction of net organic load. As a scoping exercise, a simple mathematical model was created using known absorption efficiencies (fraction of organic material digested) of blue mussels (Mytilus edulis) on diets of seston, and Atlantic salmon (Salmo salar) culture solids, to estimate the resulting organic fecal load of blue mussels on a mixed diet. The organic load from the mussel feces was added to the unconsumed load of salmon culture organics to determine the net IMTA organic load. The dietary proportion threshold (DPT) is the percentage of fish culture solids in an extractive species diet that results in no change in net organic load at an IMTA site. The DPT of salmon culture solids that must be exceeded for mussel culture to reduce the net IMTA site organic load is 14.5% for salmon feces and high-quality seston, 19.6% for salmon feces and lowquality seston, 11.5% for salmon feed fines and high-quality seston, and 15.6% for salmon feed fines and low-quality seston. A net reduction of organic load occurs if the amount of salmon culture organics absorbed (digested) by mussels exceeds the organic fecal load produced by indigestible seston components. Changes in total particulate matter consumed by a mussel population or changes in the amount of salmon culture solids available did not change the DPT, although these factors did influence the magnitude of net organic load increases or decreases. Whether DPTs are achievable is a function of many biophysical parameters, and these avenues are not pursued in this study. However, knowledge of DPTs can be useful to frame expectations of nutrient mitigation and to assist in the interpretation of augmented growth and tracer data as a means to infer nutrient reduction potential.

Quantitative polymerase chain reaction studies have detected Vibrioparahaemolyticus virulence genes (hemolysins tdh and trh) in Rhode Island oysters and waters. Illness caused by V. parahaemolyticus is currently rare in Rhode Island; however, there is concern over increasing aquaculture and water temperatures. The aim of this study was to characterize further the genetic diversity of V. parahaemolyticus in Rhode Island to determine disease risk. The genetic profile of pathogenic (tdh and/or trh ) strains and environmental (tdh-/trh-) strains of V. parahaemolyticus isolated from Rhode Island oyster and water samples was compared with pandemic and clinical strains using repetitive extragenic palindromic polymerase chain reaction. Of the 291 V. parahaemolyticus colonies isolated, 27 were pathogenic strains, with 25 of 291 (9.0%), tdh-/trh ; 1 of 291 (0.3%), tdh /trh ; and 1 of 291 (0.3%), tdh /trh-. Rhode Island isolates did not cluster closely with pandemic or clinical strains. Isolates containing tdh and/or trh genes from Rhode Island waters were predominantly tdh-/trh , in contrast with a predominance of tdh /trh- or tdh /trh strains in Alaska, the Pacific Northwest, and the Gulf of Mexico. Similar to other studies in the United States, a high level of genetic diversity in pathogenic and environmental strains of V. parahaemolyticus was seen. This study clarified the diversity and virulence gene content (tdh and trh status) of V. parahaemolyticus isolates from Rhode Island waters.

Filter-feeding molluscan shellfish (oysters, mussels, clams, and so forth) are grown in areas classified for sanitary quality under EU Regulation 854/2004 on the basis of Escherichia coli monitoring. Rationalizing monitoring programs through use of a single-indicator shellfish species, rather than monitoring several species, has the benefit of reducing cost. To protect public health, the indicator must show an equivalent or higher level of contamination than the species it represents. This study, using a well-established statistical method (Bland-Altman method comparison) on routine monitoring data, demonstrates that the contamination ratio between species at the same site may change across the range of contamination levels. Nevertheless, an accumulation ordering was established as follows: The common cockle Cerastoderma edule, Tapes philippinarum (Manila clam), and Mytilus spp. (mussels) are broadly equivalent, and each shows a greater level of accumulation than the oysters Crassostrea gigas (Pacific oyster) and Ostrea edulis (native oyster), which both accumulate to a similar extent. Last, Ostrea edulis shows a greater level of accumulation than Mercenaria mercenaria (American hard clam). The data suggest that the use of Mytilus spp. may alone provide an adequate index of fecal pollution impacting the growing areas in England and Wales.

Bivalve shellfish are well-known vectors for human pathogens. Recent research on commercial shellfish beds has shown that the bacterial reservoir contained within the shellfish flesh in situ is often not representative of the microbial quality of the shellfish at the point of sale. This study investigates whether barnacles living on the surface of mussels represent a potential bacterial reservoir within shellfish beds and assesses their potential as a vector for human pathogen transfer. Barnacle and mussel samples were collected from 3 independent intertidal mussel (Mytilus edulis Linnaeus, 1758) beds and subjected to standard microbiological testing and ecological evaluation. Our results show that coliform concentrations were significantly higher in barnacles than in the corresponding mussels, per unit area, across all surveyed sites. The dominant observed barnacle species was the invasive barnacle Austrominius (Elminius) modestus (Darwin, 1854) which has outcompeted native species in the region and contains increased coliform bacterial concentrations relative to other observed barnacle species. This study concludes that, where present, epizoic barnacles represent a significant reservoir for bacteria within shellfish beds and, therefore, have the capacity to act as vectors for human pathogens. Further work is needed to quantify the subsequent viability/pathogenicity of the epizoic bacterial reservoir after shellfish harvesting and food processing.

Genome size (C value) is a fundamental characteristic of every species and is very important for the progress of cytogenetic, genomic, and phylogenic studies. However, information on the C value of phylum Brachiopoda is scarce. In this study, we collected 8 brachiopod species from Japan, including 5 from class Articulata, and determined their C values by flow cytometry. The mean C values for these 8 species-namely, Lingula anatina, Lingula reevii, Discradisca stella, Terebratulina crossei, Laqueus rubellus, Laqueus blanfordi, Terebratalia coreanica, and Platidia japonica—were 0.41 pg, 0.41 pg, 0.46 pg, 0.33 pg, 0.44 pg, 0.42 pg, 0.37 pg, and 0.31 pg, respectively. Although the C values were examined across the various taxa within Brachiopoda, we detected very little variation (approximately 1.5-fold, from 0.31 pg in P. japonica to 0.46 pg in D. stella). This low C value variation suggests that the occurrences of evolutionary events such as changing the number of transposable elements and intron size, polyploidy, and DNA loss—all of which could cause a change in genome size—are fewer than in other taxa of the animal kingdom.

We compare larval distributions of the invasive Asian shore crab Hemigrapsus sanguineus and the native fiddler crab Ucapugnax. Our study was conducted in the coastal ocean adjacent to Delaware Bay on the east coast of the United States. Subtidal circulation in the study area is dominated by the Delaware Coastal Current, which is formed by the estuarine plume that extends southward out of the bay and along the inner continental shelf. The offshore edge of the current is marked by a strong density front and by convergent circulation along the frontal boundary. Surface plankton tows were taken at fine-scale intervals along saw-tooth transects traversing the front on 3 consecutive days in early August. Coincident physical measurements delivered hydrographic data throughout the investigation. Results provided a synoptic view of larval distribution near the bay mouth and showed patchy occurrence of the 2 species within the sampling area. Approximately 8.7 × 10⁵ U. pugnax larvae were collected during the study, compared with 2.5 × 10⁴ H. sanguineus. Analysis of spatial distribution with respect to the coastal current showed a marked difference between early- and late-stage larvae for each species. Zoea stage I larvae were most common in the main stream of the coastal current. In contrast, the distribution of advanced stages was skewed toward the frontal region. Larvae entrained in the frontal circulation are likely retained near Delaware Bay, whereas those in the main stream of the coastal current may undergo long-distance transport along the continental shelf.

We used a video camera mounted on the footrope of an ocean shrimp (Pandalus jordani) trawl to measure macroinvertebrate contact and disturbance rates directly from 4 different trawl footrope configurations. One footrope without a central groundline and 2 experimental footropes with groundlines that were modified to reduce macroinvertebrate impact were compared with the most common footrope style used in the fishery: a disk-covered groundline (mud gear). Relative to mud gear, the footrope without a central groundline reduced macroinvertebrate disturbance rates 99% for sea whips (Halipterus spp., P < 0.01), 100% for sea stars (Asteroidea) and anemones (P < 0.05), and 96% for Dungeness crabs (Cancer magister, P < 0.001). The experimental footrope incorporating a PVC pipe-covered groundline reduced disturbance rates for sea whips and Dungeness crabs by 63% and 55%, respectively (P < 0.001), but not for sea stars or anemones. The experimental footrope incorporating elevated sections of groundline reduced disturbance rates 100% for Dungeness crabs (P < 0.001). This study demonstrates that underwater video equipment can be used to measure quickly changes in macroinvertebrate disturbance rates from different ocean shrimp trawl footrope configurations. Our data also show that constructing shrimp trawl groundlines from smoother materials and with modifications to elevate or eliminate portions of the groundline have the potential to reduce significantly trawl-induced disturbance rates of benthic macroinvertebrates.

The culture of the indigenous pink shrimp Farfantepenaeus brasiliensis was investigated in the Patos Lagoon estuary in southern Brazil. The study analyzed the effects of stocking density on growth performance and survival off. brasiliensis in estuarine cage culture. Juvenile F. brasiliensis (mean weight, 1.15 g) were stocked at densities of 10 shrimp/m², 20 shrimp/m², and 40 shrimp/m² in 4-m² PVC-coated polyester cages; a commercial shrimp diet was offered daily via feeding trays. Approximately every 15 days, shrimp were sampled and weighed to estimate growth performance. At the end of the experiment (65 days), all shrimp were weighed and counted to determine the final biomass and survival rate, respectively. Survival rates did not differ significantly (P < 0.05) among treatments (91.7%-95.3%), whereas mean final weight was greater (P < 0.05) in the stocking density of 10 shrimp/m² (7.93 ± 0.06 g). However, the best results of biomass production were recorded in the treatments with 20 shrimp/m² and 40 shrimp/m², reaching 127.81 ± 17.93 and 209.01 ± 23.46 g/m², respectively. Results from the current study suggest the biological and technical viability of F. brasiliensis cage culture in the Patos Lagoon estuary.

The effect of periods of preslaughter fasting on muscle quality and digestive enzyme activity of farmed whiteleg shrimp Litopenaeus vannamei was investigated. The fasting periods for the control, treatment 1 (T-1), and treatment 2 (T-2) groups were 0, 1, and 2 days, respectively. Higher compositions (P < 0.05) of crude protein and crude fat were observed between the control and T-2 groups. In addition, there was significant difference in crude fat between treatments T-1 and T-2. With regard to pH, total volatile basic nitrogen, and K value, no significant differences were detected across all groups; however, significant differences (P < 0.05) were obtained in hardness, springiness, and chewiness of shrimp muscle between the control and T-2 groups. According to the results of total viable counts, preslaughter fasting was most effective at controlling the growth of microorganisms. A significant difference was also observed (P < 0.05) in protease and lipase activities between the control and T-2 groups, which indicated that the 1-day fasting period prior to slaughter could firm muscle texture, increase enzyme activities, improve fat deposits, and decrease microbial growth of whiteleg shrimp, thus improving muscle-quality attributes of the whiteleg shrimp.

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 13^th 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 c