Aspects Of Aquaculture Research Articles

Extraction and Utilization of Chitin and Chitosan from Waste Yields of Economically Important Crustaceans and Molluscs for Improved Fish Production

Background: Every year, about eight million tons of different species of crustacean shells are produced, with several million tons of various mollusc shells world-wide. These shell wastes are usually disposed into the water body or mainland, littered everywhere, with significant impact on the environment. Aim: To provide a profitable way of reducing and possibly removing shell wastes, and harness them for a better purpose through an eco-friendly and sustainable technological approach. Main Body of the Abstract: This review underscores a broad list of economically important crustaceans and molluscs, harvestable in Nigeria coastal waters whose shells usually ended up as wastes. Chitin, being the primary component of these wastes can be extracted and deacetylated into chitosan, or synthesized into nanoparticles for better applications in various aspects of aquaculture. Both chemical and biological methods of chitin extraction were discussed, however, bioextraction method was recommended due to its eco-friendliness, biocompatibility, and non-hazardousness. Various ways by which these shell wastes can be processed and utilized for improve aquaculture practices were also discussed. These include fish growth enhancement, pond water treatment, as antioxidant, as immuno-stimulant, as antimicrobial, as drug carrier, and several other purposes. Conclusion: There are much hidden wealth in these fisheries by-products (Crustacean and Mollusc shells) if properly valorized. It has a great potential to transform aquaculture industry, and bring significant, and sustainable economic development in Nigeria.

Review Paper on Recent Advances of Biotechnology Application to Aquaculture Development

Recent advances in biotechnology have significantly impacted aquaculture production, revolutionizing the industry. which explores key developments in applying biotechnological tools to enhance various aspects of aquaculture. Molecular techniques, such as genetic manipulation, have enabled the selective breeding of fish for desirable traits, improving growth rates, disease resistance, and overall productivity. Furthermore, the application of advanced genomics and bioinformatics has facilitated the identification of specific genes associated with important traits, paving the way for precision breeding. Biotechnological interventions also extend to disease management in aquaculture. Novel diagnostic methods based on molecular biology enable early detection of pathogens, contributing to effective disease prevention and control. Vaccines developed through biotechnological approaches have shown promise in protecting aquatic species against various infections, reducing reliance on traditional antibiotics. Nutrition is another critical aspect benefiting from biotechnological advancements. Genetically engineered feed formulations, enriched with essential nutrients, enhance the overall health and growth of aquaculture species. Furthermore, by enhancing feed conversion efficiency and waste management, probiotics and prebiotics obtained from biotechnological processes aid in the development of sustainable and ecologically friendly practices. Aquaculture and biotechnology are integrated in environmental conservation and monitoring projects. Aquatic organisms are guaranteed ideal conditions through real-time water quality monitoring made possible by biosensors and molecular tools. Utilizing genetically engineered organisms, bioremediation techniques help to lessen the negative environmental effects of aquaculture operations. In conclusion, recent advances in biotechnology have propelled aquaculture towards a more sustainable, efficient, and environmentally conscious industry. The integration of molecular techniques, genetic manipulation, diagnostics, and environmental monitoring has opened new avenues for addressing challenges and optimizing production in aquaculture. The continued exploration and application of biotechnological tools hold great promise for the future of this crucial food production sector.

Enhancing aquaculture using nanotechnology: a review

The advent of nanotechnology is a laudable discovery, and to a large extent, it has potentials to solve many nagging problems in aquaculture industry. For instance, the challenge of recurring resistance of bacteria to antibiotics, and the myriad of different antibiotics in the market coupled with their toxic effect on fish and water is a serious concern. Nanotechnology provides new tools (Nanomaterials) which can find applications in various aspect of aquaculture with little or no risk of toxicity. These include: Nanosensors, DNA nanovaccines, nanogene delivery, smart drug delivery, nanobarcoding, fish growth enhancement using nanoselenite, nanodelivery of nutraceuticals, nanofilteration, nanopolymers, nanocoating, nanofeed to improve buoyancy and availability of feed during feeding, and nanonet treatment and so on. These products are readily available in the market. They can also be synthesized for application in the areas highlighted above. This paper presents a review on nanotechnology and its application to enhance various aspects of aquaculture with a view to finding effective management strategy to solve hydra-headed challenges bedevilling aquaculture industry by maximizing the full potential of nanomaterials

Exploring the Potential of Nanotechnology in Fisheries and Aquaculture: Opportunities and Implications

Aquaculture has emerged as one of the fastest-growing global food industries in recent years, playing a vital role in meeting the increasing demand for animal protein. However, several challenges, such as disease prevalence, chemical contamination, environmental degradation and inefficient feed utilization, have significantly impeded the sector's ability to contribute effectively to global food security. To address these challenges, considerable efforts have been made to leverage advancements in science and technology within aquaculture. Nanotechnology has emerged as a promising and effective tool to tackle these challenges across various aspects of aquaculture, including fish nutrition, biotechnology, genetics, reproduction, pathology and environmental sustainability. The utilization of emerging nano-materials, such as nano-elements enriched feed, has notably enhanced fish growth and has been applied in aquatic systems to mitigate pollutants, thereby reducing treatment costs. Furthermore, integrating genetically manipulated techniques with nano-biotechnology has led to significant advancements in fish genetics research. Innovative nanotechnology applications, such as nano-sensors, DNA nano-vaccines and drug delivery systems, have revolutionized fish health, reproduction and immune system management. Additionally, nanotechnology is increasingly employed in the fish processing industry to ensure sterile packaging, precise flavoring and high-quality products. Moreover, bio-nano-engineering techniques for optimal utilization of fishery wastes and the implementation of green nanoparticles signify a promising era in post-harvesting practices. This comprehensive review aims to delve into nanotechnology's diverse and good applications in aquaculture, exploring its potential and the challenges it presents.

Robot-assisted Aquaculture and Sustainable Seafood Production for Enhanced Food Security

This paper explores the integration of robotics in aquaculture practices to achieve sustainable seafood production, thereby enhancing global food security. With the increasing demand for seafood and the challenges posed by overfishing and environmental changes, innovative solutions are required to ensure a consistent supply of high-quality seafood. Robotic technologies offer promising avenues for optimizing various aspects of aquaculture, including monitoring, feeding, disease detection, and habitat management. Through a comprehensive review of recent advancements and case studies, this paper highlights the potential benefits, challenges, and future directions of robot-assisted aquaculture systems. By leveraging automation, data analytics, and artificial intelligence, the aquaculture industry can achieve greater efficiency, reduced environmental impact, and enhanced seafood availability, ultimately contributing to improved food security on a global scale.

Exploring the Therapeutic and Nutritional Significance of Bay Laurel (Laurus nobilis) as a Feed Additive in Aquaculture

The exploration of medicinal plants as natural and benign compounds in aquaculture presents a promising alternative to conventional antibiotics and immune prophylactics. In the domain of aquaculture, these plants serve dual roles as both chemotherapeutics and feed additives. Many plants and their derivatives contain an array of bioactive compounds, such as phenolic, polyphenolic, alkaloid, quinone, terpenoid, lectin, and polypeptide compounds, showcasing their effectiveness as alternatives to antibiotics, chemicals, vaccines, and synthetic compounds. Extensive research highlights the positive impact of incorporating herbs into fish diets, contributing to enhanced growth and disease resistance.
 The incorporation of herbs and herbal products into fish diets not only proves cost-effective but also aligns with environmental sustainability, exhibiting minimal side effects on both fish and consumers. Plant extracts are recognized for their diverse benefits, including growth promotion, appetite stimulation, tonicity enhancement, immunostimulation, facilitation of cultured species maturation, and properties such as stress reduction, sexual stimulation, and antipathogenic effects in fish.
 This comprehensive review focuses on the significant role of bay laurel (Laurus nobilis) in aquaculture, serving as a growth promoter, immunostimulant, and antioxidant. Bay laurel emerges as a medicinal herbal plant, offering a viable alternative to antibiotics with a multifaceted impact on aquaculture production and development. The review delves into the mode of action through which bay laurel enhances various aspects of aquaculture, emphasizing its potential as a valuable asset in sustainable and health-conscious fish farming practices. By exploring the diverse bioactive compounds present in bay laurel, this review contributes to a deeper understanding of its applications and implications in the ever-evolving landscape of aquaculture.

Regional communication and media analysis of aquaculture in Atlantic islands

The way the media portrays aquaculture-related events can influence how this industry is perceived by the public and affect its success. Since media are an important source of public information, media content analysis has been carried out in several regions of the world. This study aimed to determine which aspects of aquaculture were more exposed and how they were discussed by regional media in the Madeira archipelago, an oceanic group of Portuguese islands. Analysis of aquaculture’s media coverage in the two most-read regional newspapers of Madeira was carried out over a 5-year period (2017 to 2021). For each news article, the assessment focused on the geographic scope, the main topics covered, the stakeholders with access to the debate, and the general tone of the article (risk/benefit framework). A total of 297 articles were analyzed. Results indicate the occurrence of trigger events that contributed to a shift in the amount of news published and in the way media framed aquaculture. In general, political and economic issues dominated the coverage, whereas social, environmental, scientific, and landscape matters received less media attention. The voice of the government was predominant throughout the 5 years in analysis and aquaculture was generally framed with a balanced tone, slightly more negative. Open and transparent communication between the stakeholders and the media is fundamental for the sustainable development of the aquaculture industry.

Genome-wide analysis facilitates estimation of the amount of male contribution in meiotic gynogenetic three-spined stickleback (Gasterosteus aculeatus).

Gynogenetic embryos - those inheriting only maternal DNA - can be experimentally created by fertilizing eggs with radiation-treated sperm containing inactivated paternal chromosomes. Diploidy in the zygotes can be maintained through prevention of the second meiosis or restored by preventing the first mitosis after the maternal chromosome complement has been replicated. These gynogenetic organisms are useful in many fields including aquaculture, evolutionary biology and genomics. Although gynogenetic organisms have been created in numerous species, the completeness of uni-parental inheritance has often been assumed rather than thoroughly quantified across the genome. Instead, when tests of uni-parental inheritance occur, they typically rely on well-studied genetically determined phenotypes that represent a very small sub-set of the genome. Only assessing small genomic regions for paternal inheritance leaves the question of whether some paternal contributions to offspring might still have occurred. In this study, the authors quantify the efficacy of creating gynogenetic diploid three-spined stickleback fish (Gasterosteus aculeatus). To this end, the authors mirrored previous assessments of paternal contribution using well-studied genetically determined phenotypes including sex and genetically dominant morphological traits but expanded on previous studies using dense restriction site-associated DNA sequencing (RAD-seq) markers in parents and offspring to assess paternal inheritance genome-wide. In the gynogenetic diploids, the authors found no male genotypes underlying their phenotypes of interest - sex and dominant phenotypic traits. Using genome-wide assessments of paternal contribution, nevertheless, the authors found evidence of a small, yet potentially important, amount of paternally "leaked" genetic material. The application of this genome-wide approach identifies the need for more widespread assessment of paternal contributions to gynogenetic animals and promises benefits for many aspects of aquaculture, evolutionary biology and genomics.

Aquaculture Status in Southern Bangladesh With Special Emphasis on Disease Induced Loss

Culture fisheries contributes a major share of fisheries production of Bangladesh which is the accumulation of aquaculture production of every fish farms of the country. However, the actual production of cultured fish (finfish and shellfish) and cost-benefit of the farms are not well documented. Moreover, the farms must overcome a lot of constrains for sustainable production. The present study was thus designed to determine the present aquaculture status in some parts of Bangladesh and to identify the problems for the loss of aquaculture production through questionnaire survey between July 2019 and January 2020. The study areas included Bhola, Rangamati, Khulna, Satkhira, Jashore and Madaripur upazila. In the study area, the relationship between different aspects of aquaculture was determined where pond size and production cost per hectare; pond size and profit per hectare and per unit production cost and profit were found to be significantly and positively correlated. The production and production cost per hectare were also determined which were 3.52±0.40 metric tons and 6260±987 USD, respectively. The fish farmers reported some degrees of reduction of profits compare to the profit obtained during 2018-2019. The reduction of expected profit in different regions ranged between 10 and 33%. The major causes of the production loss in the survey regions were related to disease, seed and feed. Among different diseases viral, bacterial and parasitic diseases were reported where diseases were identified based on the symptoms. Findings of the present study suggest that incorporation of management, modern technology and economic aspects for steady growth of aquaculture sector is needed in Bangladesh. Dhaka Univ. J. Biol. Sci. 31(2): 257-271, 2022 (July)

The Role of Technology in Nigerian Catfish Production: A Review

This article examines the state of Catfish production in Nigeria and the roles technology has played over the past decades. Heightened demand as a result of increased population puts considerable pressure on production. In response to this pressure aquaculturists ramped up production activities, this demand-driven increase exposes the major gaps as the industry struggles to cope with the absence of fundamental structures like inadequate structured funding, markets, processing and preservation facilities among others. Such gaps exist in all aspects of aquaculture and technology is a viable plug for many of them. The aquaculture of developing nations has certain peculiarities which predispose it to slow development. Many fishermen and aquaculturists in low-income regions are trapped in economic systems that result in relative poverty. Many reasons have been put forward to explain the dynamics behind these consequences with technology playing a major role from the consensus. Rapid advances in hatchery, water quality and molecular technology have been identified as some of the active drivers of Catfish production in Nigeria. The article focuses on the history, progress and prospects of aquaculture technology in Nigeria. It does so by reviewing the technologies already established in Catfish farming and the impact of their roles in balancing fish demand and supply.

Стажировки специалистов ТИНРО-Центра в рыбохозяйственных научных и производственных организациях Японии

In the period from 1994 to 2007, Japanese scientific and industrial fishing organizations received trainees from the TINRO-Center. The internship topics included familiarization with Japanese resource research, fish processing technologies, and some aspects of aquaculture. The article discusses the conditions that made these internships possible, as well as the change in conditions that led to the completion of this type of Russian-Japanese cooperation in fishing.

Opportunities and challenges for small-scale aquaculture: The stakeholders’ perspective in Los Lagos Region-Chile

We identify and explore the potential opportunities and challenges for promoting and expanding small-scale aquaculture (SSA) as an additional income-generating activity for coastal communities in southern Chile. Based on a conceptual model of SSA adoption decisions, we conducted field key informant semistructured interviews with stakeholders in the Los Lagos region and in the regional capital city, Puerto Montt. We conducted a qualitative analysis of the interviews to identify potential resource users’ perceptions of current SSA opportunities. Interpreting the content analysis results through the lens of economic decisions in the conceptual model, we find that weak monitoring and enforcement, difficulties in adapting to new jobs, limited recent spatial planning, constraints on access to marine user rights, and insufficient market development for marine products are among the main obstacles to the adoption of SSA. The stakeholders view SSA as an opportunity to expand marine-based productive activities under the continuous decline in wild fisheries. SSA adoption is perceived as a gradual transition process that requires cultural capital and knowledge, given the lack of familiarity with management and the legal and economic aspects of aquaculture. In contrast to the concerns of potential SSA adopters, government stakeholders emphasize concern over the lack of definitions for SSA, norms, and regulations. We discuss how public policy to promote SSA in Chile could target the key concerns of potential SSA adopters.

Supplementation of cryodiluent media with seaweed or Nile tilapia skin sulfated polysaccharides for freezing of Colossoma macropomum (Characiformes: Serrasalmidae) semen

Tambaqui, Colossoma macropomum, is an ideal fish for cultivation in captivity and it is valued in the consumer market. Studies on various aspects of aquaculture, including semen freezing, have been conducted. Despite its many benefits, cryopreservation damages the samples. Thus, to refine the existing protocols, products with antioxidant properties can be added, such as sulfated polysaccharides. This study evaluated the effect of adding sulfated polysaccharides from seaweed (green: Caulerpa cupressoides; red: Acanthophora muscoides and Solieria filiformis) and Nile tilapia skin into the tambaqui semen freezing medium. The resulting polysaccharidic samples were diluted and added to the cryopreservation medium. The semen was then collected, pooled, and subsequently frozen. The pools were diluted and frozen in solutions containing powdered coconut water (ACP-104) and 10% dimethyl sulfoxide (DMSO), and were supplemented with different polysaccharide concentrations (100, 250, 500, or 1000 μg/mL) from seaweed or Nile tilapia skin. Semen cryopreserved in an un-supplemented solution was used as control. After 45 days, the samples were thawed by immersion in a water bath (45 °C/8 s) and the membrane integrity, the morphology and, the sperm motility kinetics were evaluated. There were no differences in sperm kinetics for any of the analyzed parameters that could be linked to the polysaccharide source that was used. For membrane integrity, semen supplemented with sulfated polysaccharides from Nile tilapia skin showed better results (76.3 ± 1.9%) compared to treatments supplemented with A. muscoides (65.0 ± 1.8%), C. cupressoides (66.1 ± 1.7%), or S. filiformis (68.8 ± 1.0%), but there was no difference compared to the control (73.6 ± 2.9%). For morphology, the best results were observed in semen supplemented with C. cupressoides (86.7 ± 0.8%) and S. filiformis (87.7 ± 1.0%) polysaccharides at 100 μg/mL. For the mean path velocity (VAP), semen treated with 250 μg/mL of polysaccharides was significantly faster for A. muscoides (21.1 ± 2.4 μm/s) compared to S. filiformis (15.8 ± 1.7 μm/s). However, at 1000 μg/mL, these two red algae shown to be more efficient than the green algae. In C. cupressoides, 1000 μg/mL of polysaccharides showed lower velocity (13.8 ± 1.5 μm/s) than the other concentrations. In S. filiformis, 100 μg/mL and 1000 μg/mL of polysaccharides did not differ and presented higher VAP than 250 μg/mL and 500 μg/mL. Therefore, the addition of sulfated polysaccharides extracted from aquatic sources to ACP-104 and 10% DMSO solution is safe and has a potential of applicability on C. macropomum semen cryopreservation.

Understanding community perception on aquaculture: Lessons from Mauritius as an ocean state

Abstract. Nirsimloo P, Mattan-Moorgawa S, Bhagooli R. 2019. Understanding community perception on aquaculture: lessons from Mauritius as an ocean state. Ocean Life 3: 47-53. Aquaculture is considered as one of the fastest food production industry during the past decade and holds high importance in fulfilling the global seafood demand. Globally, limited studies have been conducted on the social acceptability of aquaculture. It thus remains a key challenge to understand the perceptions of people on this subject in order to manage fish farming in a sustainable way. A survey-based approach was developed in order to have an in-depth assessment of perceptions and attitudes of public on aquaculture and its implications on the Blue Economy in Mauritius. Respondents’ perceptions were evaluated on five different aspects of aquaculture, namely, knowledge, socio-economics, environment, food security and implications for a Blue Economy. A total of 385 questionnaires was administered for the study from October 2016 to March 2017 and a response rate of 100% was recorded. Different statistical tests, like Spearman Correlation, Kruskal-Wallis and Chi-Square test, were used to compute data. Descriptive statistical methods revealed that 69.1% of respondents were in favor of expansion of the aquaculture industry in Mauritius. A poor but significant correlation (r=-0.0169, p<0.05) was found between favoring aquaculture expansion and perceived environmental concerns of aquaculture. A chi-square test confirmed a statistically significant association (p<0.05) between educational level of respondents and their knowledge on aquaculture. When aquaculture and Blue Economy in Mauritius were correlated, creation of employment opportunities, ensuring food security and boosting the economy of the country were factors chosen by most respondents to acknowledge the implications of aquaculture on the Blue Economy.

Presence of <em>Saprolegnia</em> spp. (<em>Oomycetes</em>) in the Sivanamman Pond and its Characteristic Features

Simultaneous improvisation in expertise and facilities in disease diagnosis have led to the identification of several previously unknown pathogens and diseased conditions. Saprolegniosis is one of the disease for which no known remedies were discovered yet. The current research was intended to study the presence and characterization of Saprolegnia spp. The study results hoped to be beneficial to many aspects of aquaculture and research on Saprolegniosis. Water sample was collected from Sivanamman pond (9°40'50.9N and 80°01'43.6E). Saprolegnia spp. was isolated by baiting method under in vitro condition. Identification and characterization was carried out on cultural, vegetative and sexual characteristics featured by Saprolegnia spp. under microscopic observation. Isolate was identified as an aquatic fungus belongs to Saprolegnia spp. with respect to the sporulation from zoosporangium and sexual reproductive structures. The sexual morphologies were significant after a starvation (26 days) in the PDA. Eucarpic mycelium was transparent, vacuolated cytoplasm contained several nuclei and produced differential oogonium with oospores. The results of present study reveal the occurrence of Saprolegnia spp. in Jaffna urban ponds and evidently prove that the mold is administrable in PDA medium.

Assessment of the use of copper alloy aquaculture nets: Potential impacts on the marine environment and on the farmed fish

The environmental effects of the copper aquaculture nets were estimated by a multidisciplinary approach. A copper alloy net (brass net) cage and a conventional net cage with Cu2O antifouling paint were established at a fish farm in Bathy Limani Bay, Paleros, Aetolia Acarnania region, Greece, for a 1-year period. Copper concentrations in abiotic (water, sediment, particulate matter) and biotic (organisms) samples were measured. The biological effects of copper on organisms (mussels, farmed fish) were further assessed with a battery of biochemical biomarkers (acetylcholinesterase, catalase, glutathione-S-transferase, metallothioneins). During the first 6months of cage installations, the copper alloy (brass) net seemed to release more Cu to the surrounding environment and affect the biota more compared to the conventional net, although non-significant correlations were found between biotic and abiotic variables. However, at the end of the experimental period, equilibrium was reached in the copper alloy (brass) net cage with similar values of dissolved Cu and Cu in organisms as the conventional net cage. An exception to these results was the sampling of August 2013, where an increased effect on water chemistry and mussels in the conventional cage was observed, which may be attributed to the use of antifoulants on the examined conventional net or on the surrounding conventional nets. No accumulation of Cu in sediment was detected. No consistent temporal or spatial trend was observed for biochemical biomarkers. In addition, for both experimental cages and in all sampling periods, dissolved Cu never reached the maximum permissible limits in the Greek legislation, and Cu concentrations in the farmed fish and mussels do not exceed established limits for edible parts set by Food and Agriculture Organization of the United Nations (FAO). Statement of relevanceIn this manuscript, a set of methodological tools and indicators were studied in order to assess the potential impacts of the use of copper alloy aquaculture nets on farmed fish and, eventually, the marine environment of the Mediterranean Sea. The authors believe that the aim of this work is within the journal's scope and the presented results, analysis and interpretation will be of interest to scientists involved in various aspects of aquaculture (management, environmental pollution, ecotoxicology, food safety etc.).

Socio-Economic Considerations of the Aquaculture Industries in Cebu and Siquijor, Central Visayas, Philippines

Abstract Aquaculture industry has grown globally to fill in the shortage of fish supply from the sea. A study of aquaculture industries in ICRMP sites of Central Visayas was conducted to determine the socio-cultural and economic aspects of aquaculture. Results revealed that 79% of aquaculture systems are in freshwater and brackish ponds with 50% Oreochromis niloticus and 43% Chanos chanos as common cultured species. Ponds are operated by private individuals and conform to the standard culture systems of cultured species. The individuals that were employed in aquaculture industries are those that are living near the aquaculture sites which are mostly hired as caretakers and helpers and basically non-permanent and on-call basis. In spite of their employment in the aquaculture industries, communities near aquaculture sites are considered poor since majority of households are living below the poverty thresholds. There is a periodicity of consumption of aquaculture products in the community. The frequency of consumption is high during harvest time (50%) which usually happens every 3-4 months only, thus creating high demand in the community.

Density‐Dependent Impacts on Growth and Body Condition of Red Drum in Stock Enhancement Rearing Ponds

AbstractThe quality of individuals released from fish culture facilities for stock enhancement can affect success in achieving management goals. However, the quality of released individuals is not always known, and neither are the various aspects of aquaculture that influence fish quality. Quality or body condition at multiple life stages may be influenced by density‐dependent impacts on growth. Here, the influence of stocking density (number of larvae per cubic meter) at the beginning of pond culture and harvest density at the end of pond culture were assessed in relation to growth and body condition using data from 121 stock enhancement culture ponds for Red Drum Sciaenops ocellatus. While stocking density did not influence Red Drum growth rate, harvest density was a reliable predictor of growth; high density at harvest resulted in slow growth in weight (r2 = 0.33, P < 0.001) and length (r2 = 0.26, P < 0.001). No negative impacts on pond yield were observed in ponds stocked over the targeted stocking rate (988,000 larvae/ha), and mean body condition was consistent with what would be expected for individuals in wild populations. These findings suggest no observable negative biological effects of density dependence during the duration of pond culture on the quality of released Red Drum.

Abstracts Of Shellfish Technical PapersPresented at the joint meeting of theNortheast Aquaculture Conference and Exposition Milford Aquaculture Seminar and the International Conference on Shellfish Restoration Groton, Connecticut December 12–15, 2012

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

Getting to 'No': The method of contested exchange

Policy processes frequently fail to reach policy recommendations or the recommendations fail in practice. An 'antecedent failure' occurs when a policy problem is not perceived in advance as unstructured and consensus methods ill-equipped to grappling with a lack of structure are used. By contrast, dissensus can be better for structuring policy problems, and a method of 'contested exchange' has been developed and evaluated for this purpose. Disputed aspects of aquaculture provide ready examples of antecedent failure and unstructured policy problems. The method of contested exchange is used to provide structure, and a number of virtues of the method are discussed. Copyright The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com, Oxford University Press.