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AbstractSurveys in three U.S. localities (n = 523) with proposed or existing land‐based aquaculture facilities probed trust's relationship with perceived net benefits and public intentions to cooperate with siting of this novel technology. The trust, confidence, and cooperation (TCC) model posits that shared values shape willingness to be vulnerable to others (trust), while past performance shapes certainty that others will behave as expected (confidence). Trust affects confidence given moral outweighs performance information, possibly varying by familiarity. Other research suggests that trust shapes benefit and risk perceptions, which drive cooperation (defined here by potentially observable behavior: voting on siting, trying to influence government decisions directly or through citizen groups, and buying or eating facility fish). Confirmatory factor analyses suggested that a two‐factor model fit the trust/confidence measures better than a one‐factor model or a two‐factor model without inter‐factor correlation, indicating (despite a strong association of trust and confidence) that they are empirically distinct. Path analyses suggested that trust had stronger direct effects on cooperation than did confidence, reflecting the TCC notion that moral information underlying trust judgments is more influential, and stronger indirect effects through benefit‐risk judgments. Model fit was better than if the benefit‐risk mediator was omitted. Trust in government had a small direct effect on cooperation and confidence, but a large effect on trust in the corporation, and model fit was much worse if any of these paths was omitted. Low familiarity with the project lowered both model fit and trust–confidence association. We discuss implications for risk analysis theory and practice.

This book contains 17 chapters. Topics covered are: management of marine aquaculture: the sustainability challenge; marine mammals and aquaculture: conflicts and potential resolutions; recreational fishing and aquaculture: throwing a line into the pond; aquaculture: opportunity of threat to traditional capture fishermen; advances in marine stock enhancement: shifting emphasis to theory and accountability; aquatic polyculture and balanced ecosystem management: new paradigms for seafood production; the role of marine aquaculture facilities as habitats and ecosystems; mangroves and coastal aquaculture; environmental effects associated with marine netpen waste with emphasis on salmon farming in the Pacific Northwest; issues associated with non-indigenous species in marine aquaculture; genetic changes in marine aquaculture species and the potential for impacts on natural populations; what role does genetics play in responsible aquaculture; understanding the interaction of extractive and fed aquaculture using ecosystem modelling; shrimp farm effluents; fish meal: historical uses, production trends and future outlook for sustainable supplies; the use of wild-caught juveniles in coastal aquaculture and its application to coral reef fishes; contending with criticism: sensible responses in an age of advocacy.

Today's expanding field of aquaculture requires data and techniques from a wide variety of scientific disciplines, including marine and aquatic sciences, chemistry, animal nutrition, engineering, and mathematics. Since this information is typically found only in texts and technical reports specific to each discipline, it can be very time-consuming for aquaculturists to access the facts they need. Aquaculture Desk Reference solves this problem by compiling data, formulas, computations, conversions, and technical information from diverse sources into one manual designed for aquaculture professionals. It serves as a quick source of technical know-how that will drastically reduce the time spent on fact-finding and calculation. Information needed by aquaculturists and growers in both planning aquaculture projects and day-to-day operations of aquaculture facilities is included. Relevant data from fields such as physical and chemical oceanography, engineering, and the biological sciences is simply indexed for easy retrieval. Particularly valuable are the extensive tables related to water chemistry, fluid mechanics and engineering, nutrition, and disease treatment. Specifications for construction materials and many other topics are organized in a concise, understandable fashion. Among the other important areas covered are properties of water, hatchery methods, phytoplankton culture, feeds and food conversion, aquaculture ponds, pumps and plumbing, water treatment, and properties of materials used in aquaculture. Where appropriate, the author provides equations and formulas along with simple examples so users can adapt the information to particular situations. Aquaculture Desk Reference is an essential time-saving resource for all practicing aquaculturists in industry, academic research, and education

Salmon farming is a large and still growing industry in Norway. Like all industries that utilize a country's natural resources, will lack of focus on the environmental impact potentially lead to negative consequences. To ensure sustainability and protect the environment, the Norwegian government use production licenses and emission permits to determine how large a salmon production can be, without adversely affecting the recipient water. There is restricted knowledge about the emission from land-based juvenile farms and about the difference between flow-through and a RAS in terms of emissions. In addition, are the licenses given by the county governor office, potentially leading to different practices between the different counties. This master thesis asses this subject further by looking into two research questions: • Does the licensing system urge or stimulate to reduce the emissions from land-based salmon farms, both FTS and RAS? • Is it possible to develop a better model for calculation of emissions from land-based salmon farms, both FTS and RAS? To answer these two questions the master is worked out in three parts: 1. Assessment of today's emission permits for land-based freshwater facilities, FTS and RAS 2. Development of a new model (VØF) for calculation of waste from land-based freshwater facilities, based on production system, production plan and mass balance estimates 3. Comparing VØF-model to the models used by the county governor's office for estimation of waste from land-based aquaculture freshwater facilities. Today most of the emission permits demand a percentage purification of the total production without separating dissolved and particle waste and is more often given to RAS-facilities. This may lead to an incorrect assumption of the emissions from a facility because the tonnage waste produced and released is never actually specified. Secondly, will restrictions in terms of maximum feed usage, biomass, and the number of fish produced, give no room or motivation for self-improvement to reduce waste more effectively. If not tended to, this waste licensing system will certainly not improve the industries sustainability in the upcoming future. Since the waste from fish farms is dependent on the feed, the feed content for different salmon life stages was mapped. In addition, literature shows that the salmon in average excrete following values of the total nutrient input: 18,33% of C, 52% of P and 15,40% of N as particulate waste, and 3% of C, 18% of P, and 44,40% of N as dissolved waste. The remaining C waste is discharged over the gills of the salmon in the form of 41% CO2. The new model (VØF-model) estimated waste with the mass balance principle with a literature background of distribution from a 100% feed input. In this thesis, the feed input to the model was based on six theoretical production plans with weekly calculations on biological needs in salmon production. The production plans simulated production of 100 000 salmon smolt for the sizes 100g, 300g, and 500g, in both FTS and RAS. The focus in the VØF-model is chosen to locate differences in nutrient content of C, P, and N in salmon waste from FTS and RAS. The VØF-model showed that the total average feed content changed with the different compositions in fry, fingerling, and smolt feed. The model also showed the following overall average content in RAS feed, compared to FTS feed for production of the three fish sizes: - 6,5 g/kg less C, 5,0 g/kg less N and 0,2 g/kg more P in a 100 g production, - 7,2 g/kg less C, 3,4 g/kg less N and 1,3 g/kg more P in a 300g production, - 6,8 g/kg less C, 3,2 g/kg less N and 1,4 g/kg more P in a 500g production, This thesis demonstrated that both particle waste production and dissolved waste production from salmon, strongly correlates with the feed input, as a total and on a weekly basis, as well as the production plan. From this, it is clear that the water temperature, which is heavily affecting growth, is a crucial factor for waste production and is responsible for causing substantial waste differences between the FTS and RAS productions, but also between the 100g, 300g and 500g productions in general. Results showed that salmon waste produced under RAS conditions had following differences compared to salmon waste produced under FTS conditions: - 0,85% less C, 6,29% less N and 1,42% more P in the 100g, - 1% less C, 4,06% less N and 8,27% more P in the 300g, - 1,53% less C, 4,44% less N and 8,72% more P in the 500g, Results indicate that in land-based salmon farming, particle waste makes up 85,94% of C, 74,29% of P and 25,75% of N of the total waste produced. Theoretically, this part of the waste is simpler and more cost-effective for farmers to purify, compared to the remaining dissolved part. When comparing the VØF-model to the government's newest estimation model, the highest percentage deviation in total waste from the VØF-model was, C + 11,13% (500g RAS), P +18,51% (500g FTS) and N – 6,13%. As the government's model calculated the amount of DW in sludge to increase with increasing fish size, this DW variation presumably lead to an inaccurate estimation according to the mass balance principle for salmon used in the VØF-model. The new county governor model did not acknowledge the difference of C, P, and N content in the feed, the variations of these nutrients through the production cycle, and how this affected the overall production of waste. The sum of these factors results in a miscalculation of the dissolved waste produced when estimating with the new county governor model, compared to the VØF-model, with the highest percentage deviation being C +79,12% (500g RAS), P +71,97% (500g FTS) and N -8,26% (500g RAS). ; M-AA

Highlights of the aquaculture production systems research program, focusing on recent research at the University of Guelph. ; More than 25 faculty, staff and graduate students conduct production systems research related to farmed fish. State-of-the-art facilities at Alma Aquaculture Research Station provide a foundation for their work. Industry and government support this leading edge research that focuses on nutrition and feeding management, ecosystem impacts and mitigation, health management and genetic improvement. ; Project supported by Agri-Food and Rural Link, Mobilizing Agri-food and Rural Research Knowledge. A program of the OMAFRA-U of G Partnership Program. http://www.uoguelph.ca/omafra_partnership/en/partnershipprograms/KTT.asp

Este artículo contiene 11 páginas, 3 tablas, 3 figuras. ; Ascidians are important both as invasive species and as a fouling group in artificial marine habitats, causing negative impacts in aquaculture settings and the surrounding environment. The Ebro Delta is one of the major centres of bivalve production in the Mediterranean and is affected by proliferation of ascidian species (mostly introduced forms). Knowledge of the patterns of settlement and growth of the fouling species is mandatory to attempt mitigation measures. Settlement PVC plates were deployed from May to September 2015 at different depths (0.2, 1 and 2 m) in the Ebro Delta oyster aquaculture facilities. The occurrences of all species and the area cover of a selected subset of 6 species were monitored on a monthly basis from June 2015 to December 2016. Fifteen species were found, of which 10 are introduced. There were some differences between the deployed plates and the oyster ropes in species abundance and composition, likely due to differences in substrate complexity. For instance, Didemnum vexillum and Clavelina oblonga occurred in few plates in contrast to their abundance on oysters. The most abundant species were Styela plicata and Clavelina lepadiformis, which together with Ecteinascidia turbinata showed a preference to grow on plates deployed in May and June. Most of the species grew more at 0.2mdepth than at deeper plates. Thus, to minimise fouling on bivalves, spat immersion during fall and below 1mdepth is recommended. The number of occurrences and cover of the species was found to be similarly informative; suggesting that a periodic monitoring of species occurrence on replicate plates is sufficient for detecting new introduced species as soon as possible and will provide information useful for management. ; This research was funded by project CHALLENGEN CTM2013-48163 from the Spanish Government. MC, VO, MP and XT are part of the research group 2014SGR-336 of the Generalitat de Catalunya. ; Peer reviewed

The shortage of wild fishery resources and the rising demand for human nutrition has driven a great expansion in aquaculture during the last decades in terms of production and economic value. As such, sustainable aquaculture production is one of the main priorities of the European Union's 2030 agenda. However, the intensification of seafood farming has resulted in higher risks of disease outbreaks and in the increased use of antimicrobials to control them. The selective pressure exerted by these drugs provides the ideal conditions for the emergence of antimicrobial resistance hotspots in aquaculture facilities. Omics technology is an umbrella term for modern technologies such as genomics, metagenomics, transcriptomics, proteomics, culturomics, and metabolomics. These techniques have received increasing recognition because of their potential to unravel novel mechanisms in biological science. Metagenomics allows the study of genomes in microbial communities contained within a certain environment. The potential uses of metagenomics in aquaculture environments include the study of microbial diversity, microbial functions, and antibiotic resistance genes. A snapshot of these high throughput technologies applied to microbial diversity and antimicrobial resistance studies in aquacultures will be presented in this review. ; info:eu-repo/semantics/publishedVersion

Globally, humans are harvesting the majority of capture fisheries at or above maximum sustainable yield, yet the demand for seafood is ever growing, a trend that cannot be met by the apparent plateau or possible decline of capture fisheries. Aquaculture appears to be an essential part of the solution, although it has become an increasingly controversial form of food production due to human health concerns and negative environmental impacts, as it has developed into a viable industry over the past 20 years. The US Department of Commerce is currently drafting legislation for the purpose of creating a streamlined permitting process for offshore aquaculture facilities in the US exclusive economic zone (EEZ). The objective of the legislation, referred to as the National Offshore Aquaculture Act of 2005, is to increase current US aquaculture production from a $1 billion per year industry to $5 billion annually by the year 2025. However, permitting aquaculture facilities in federal waters may have negative impacts on marine biodiversity in regards to increased disease transmission to wild stocks, pollution, escaped exotic or genetically modified species, as well as interference with natural marine mammal behavior and protected species. The purpose of this review is to evaluate the sustainability and feasibility of the US plan to intensity aquaculture efforts in the US EEZ through current case studies and interviews of industry experts and scientists, and to produce recommendations for a future policy framework based on the impacts to marine biodiversity. Given the many uncertainties, the Department of Commerce should consider the following limits to offshore aquaculture projects: 1) No aquaculture activities producing non-native species should be permitted in federal waters to protect wild species that may be at risk of hybridizing or losing habitat to nonendemic escapees; 2) A moratorium on genetically modified species should remain until their safety can be proven in land locked closures over several generations; 3) Antibiotics and pesticides should only be administered to fish in quarantine by a veterinarian, and mandatory reporting of therapeutic types and quantities used by offshore aquaculture farms will assist in public awareness and project transparency; 4) Pens should not be sited in areas that overlap with marine mammal activities that will cause disruption, stress, or disease to these animals in compliance with the Marine Mammal Protection Act; 5) Identify areas that will be restricted from offshore aquaculture activities that may pose additional stress to protected species or recovering wild fish stocks. Aquaculture exclusion zones should be determined in collaboration with fisheries management councils, and abide by the protections afforded by the Endangered Species Act.

World aquaculture food production rises every year, amounting, by 2018, to another all-time record of 82.1 million tonnes of farmed seafood, with Asia leading global production. In Europe, although coastal countries present historical fishing habits, aquaculture is in true expansion. Norway, the leading European producer, is the eighth main producer worldwide. Portugal is a traditional fishing country but has invested in the development of aquaculture for the past decade, attaining, by 2018, 13.3 tonnes produced, making Portugal the 16th main producer amongst European Union member states that year. Most Portuguese aquaculture facilities operate in coastal systems, resorting to extensive and semi-intensive rearing techniques. In Portugal, marine food production in transitional systems is particularly interesting as the practice has, worldwide, been continuously substituted by intensive methods. In fact, facilities in transitional systems have developed over time and products gained higher commercial value. Clams and oysters corresponded, together, to over three quarters of total mollusc production in Portugal in 2018, while gilthead seabream and European seabass made up nearly all fish production in coastal environments. The state of aquaculture practices worldwide is reviewed in the present work, providing a particular focus on Portugal, where considerable development of the aquaculture sector is expected.

World aquaculture food production rises every year, amounting, by 2018, to another all-time record of 82.1 million tonnes of farmed seafood, with Asia leading global production. In Europe, although coastal countries present historical fishing habits, aquaculture is in true expansion. Norway, the leading European producer, is the eighth main producer worldwide. Portugal is a traditional fishing country but has invested in the development of aquaculture for the past decade, attaining, by 2018, 13.3 tonnes produced, making Portugal the 16th main producer amongst European Union member states that year. Most Portuguese aquaculture facilities operate in coastal systems, resorting to extensive and semi-intensive rearing techniques. In Portugal, marine food production in transitional systems is particularly interesting as the practice has, worldwide, been continuously substituted by intensive methods. In fact, facilities in transitional systems have developed over time and products gained higher commercial value. Clams and oysters corresponded, together, to over three quarters of total mollusc production in Portugal in 2018, while gilthead seabream and European seabass made up nearly all fish production in coastal environments. The state of aquaculture practices worldwide is reviewed in the present work, providing a particular focus on Portugal, where considerable development of the aquaculture sector is expected.

This essential volume offers the most up-to-date and comprehensive information on aquaculture engineering available, compiling basic engineering information for aquaculture facilities in a single resource. It will enable the reader to design and operate aquaculture facilities that meet the needs of an increasing, yet competitive market for cultivated seafood products. Taking a practical, how-to approach, the author: gives a broad overview of contemporary aquaculture practice and species that are cultivated, and describes how to select sites for aquaculture operations; examines the effects of water quality on cultured animals, and provides guidelines on state-of-the-art recirculation, aeration, and disinfection systems, as well as solids removal and biological filtration, demonstrating how to ensure product quality; details the latest methods of pond, raceway, tank and pump design, plus flow estimation and measurement, allowing the reader to optimize the productive capacity of facilities; includes over 200 illustrations that enhance the text. Integrating the biological, chemical and structural aspects of successful aquaculture, this unique volume is an indispensable resource for all engineers and technicians involved in this rapidly expanding industry. The clear presentation makes this book appropriate for aquaculture and engineering students

International audience ; World aquaculture food production rises every year, amounting, by 2018, to another all-time record of 82.1 million tonnes of farmed seafood, with Asia leading global production. In Europe, although coastal countries present historical fishing habits, aquaculture is in true expansion. Norway, the leading European producer, is the eighth main producer worldwide. Portugal is a traditional fishing country but has invested in the development of aquaculture for the past decade, attaining, by 2018, 13.3 tonnes produced, making Portugal the 16th main producer amongst European Union member states that year. Most Portuguese aquaculture facilities operate in coastal systems, resorting to extensive and semi-intensive rearing techniques. In Portugal, marine food production in transitional systems is particularly interesting as the practice has, worldwide, been continuously substituted by intensive methods. In fact, facilities in transitional systems have developed over time and products gained higher commercial value. Clams and oysters corresponded, together, to over three quarters of total mollusc production in Portugal in 2018, while gilthead seabream and European seabass made up nearly all fish production in coastal environments. The state of aquaculture practices worldwide is reviewed in the present work, providing a particular focus on Portugal, where considerable development of the aquaculture sector is expected.

Global aquaculture relies heavily on the farming of non-native aquatic species (hereafter, NAS). NAS escapes from aquaculture facilities can result in serious aquatic bio-invasions, which has been an important issue in the FAO Blue Growth Initiative. A regulatory quagmire regarding NAS farming and escapes, however, exists in most developing countries. We discuss aquaculture expansion and NAS escapes, illustrate emerging risks and propose recommendations for improved aquaculture management across developing countries and particularly for China. In China, 68 NAS are known to have successfully established feral populations in natural habitats due to recurrent leakages or escapes; among the 68 NAS, 52 represent risks to native aquatic ecosystems. In addition to affecting a country's own biodiversity and ecosystem functions, NAS escapees can also threaten the biosecurity of shared waters in neighbouring countries. Policy implications. Non-native aquatic species (NAS) escapes have already had adverse ecological effects in China and other developing countries. The importance of this problem, however, is not adequately recognized by current conservation policies in developing countries. To conserve biodiversity and to support the goal of FAO's sustainable aquaculture, developing countries should now take responsible actions to address NAS escapes through policy and management improvements. Specifically, these countries should pass comprehensive legislation, establish effective agencies and national standards and planning and enhance integrated research and education to deal with risk assessment, prevention, monitoring and control of NAS escapes. Given that China is the world's largest aquacultural producer, China can create a model for other developing countries that will increase the biosecurity and sustainability of global aquaculture.

In aquaculture, biosecurity consists of policies, procedures and measures used to prevent or control the spread of fish disease. The focus of this research was the practice of biosecurity in the recirculation sector of finfish aquaculture in the United States and Canada. Specifically, this research: 1) identified and characterized finfish recirculation facilities in the United States and Canada; 2) assessed biosecurity utilization in these facilities; 3) examined the relationship between biosecurity utilization and fish culture variables; 4) examined the relationship between biosecurity utilization and socio-demographics of personnel operating these facilities; 5) described the attitudes, perceptions and beliefs about fish disease and biosecurity utilization of personnel, and 6) described the lived-experience of biosecurity practice of workers at these facilities. This research was comprised of two separate components using different methodologies. The first component was a self-administered, mail-back questionnaire sent to the managers of 152 finfish recirculation facilities in the United States and Canada in fall of 2001. The second component was a series of in-depth interviews conducted with 31 workers at 12 salmonid recirculation facilities in spring of 2002. Grounded theory methodology was used for the interview process and subsequent data analysis for the second component. An 86% response rate was achieved in the mail survey. Aquaculture activities using recirculation technologies were quite varied in purpose of operation, size of production, and life stages held. Four groups of fishes dominated the recirculation sector and constituted the primary production of over 45% of this sector of aquaculture. This sector was heavily reliant on ground water resources. Forty-one percent of finfish recirculation facilities did not have a secondary source of water supply. Biosecurity utilization is not homogenous within the recirculation sector. Frequency of biosecurity utilization was related to primary water source, type of fish grown, purpose of the operation and country of operation. Biosecurity was an important concern of facility operators, although among facility operators there were differences in perception of disease risk and benefits of biosecurity utilization. Analysis of results of this study resulted in formulation of the Practice of Biosecurity Theory (PBT). The theory describes a three-phase process in the practice of biosecurity: (1) orientation, when workers begin their initiation into the practice of biosecurity; (2) routine, when practice of biosecurity becomes a habitual behavior; and (3) thoughtful approach, where knowledge of fish health needs and biosecurity practices are integrated into a repertoire of biosecurity strategies that are situation- and site-specific. The practice of biosecurity was affected by three environmental conditions; personal biography, management's role, and peer pressure. This research gives educators, extension agents, researchers and government policy-makers a quantitative description of finfish recirculation aquaculture in the United States and Canada. It also provides baseline information on biosecurity utilization in recirculation aquaculture. This research provides insight into the human dimensions aspect of the practice of biosecurity and, therefore, may have application to other areas of agri-business. ; Ph. D.