Marine aquaculture is a rapidly growing industry that presents both opportunities and risks for the environment and society. Whether aquatic farming (bivalves and finfish) in the ocean can mitigate food security concerns and be done without significant ecological impact depends in large part on the governance infrastructure of the sector. This study assesses the relationships at the nation-state level between existing aquaculture policy determined by survey and literature review, indicators of the quality of governance, and assessments of the ecological potential for highly productive aquaculture. The possible socio-ecological implications of Blue Growth for nations around the world are then discussed. There are numerous unexploited opportunities for countries, like those in the Pacific and Caribbean, with good governance and growth potential to pursue marine aquaculture, particularly to potentially alleviate local food security concerns. In comparison, countries already producing marine aquaculture do not have the most biologically suitable waters (e.g., China), but are more closely aligned with private capital – showing production is clearly possible, but may be less sustainable or optimal. Notably, many countries active in the marine aquaculture space appear to have some level of associated regulation and environmental oversight, but appear to lack clear frameworks for emerging growth in the sector, particularly offshore production. This study provides one of the first global evaluations of sustainable aquaculture potential under current governance, policy, and capital patterns.
Aquaculture, Seafood, and Food Security
Climate change, observed as warming sea surface temperatures, is expected to impact the Eastern coast of Canada at a rate higher than the global average. Changes in marine abiotic conditions will impact the growth and performance of economically important bivalve species, creating an increasingly uncertain future for the bivalve aquaculture industry. Site-selection for new farms, and the management of extant ones could mitigate these potential impacts, but the implementation of this planning process is dependent on stakeholder support and engagement. Recognizing the importance of stakeholder input in management decisions, this research analyzed the perspectives of farmers, researchers, and managers from Nova Scotia (NS) and Prince Edward Island (PEI) on the relationship between climate change and bivalve aquaculture. Stakeholder perspectives were analyzed using a semi-quantitative interview method (Q methodology). These perspectives indicated the need for a higher level of integration both between stakeholder groups, namely farmers and managers, and management tools and climate change. Increased understanding between farmers and managers could be achieved through the use of researchers as knowledge brokers, collaborating and communicating with both groups. Making use of management tools, such as the ecosystem approach to aquaculture, required insurance, and adaptive management, governmental bodies on both a federal and provincial level can act as channels by which uncertainty generated by climate change can be further reduced. In summary, stakeholder perception can be used by marine planners to adapt to these foreseen changes, and to promote the expansion of this industry.
We have evaluated the cultivation potential of sugar kelp (Saccharina latissima) as a function of latitude and position (near- and offshore) along the Norwegian coast using a coupled 3D hydrodynamic-biogeochemical-kelp model system (SINMOD) run for four growth seasons (2012–2016). The results are spatially explicit and may be used to compare the suitability of different regions for kelp cultivation, both inshore and offshore.The simulation results were compared with growth data from kelp cultivation experiments and in situ observations on coverage of naturally growing kelp. The model demonstrated a higher production potential offshore than in inshore regions, which is mainly due to the limitations in nutrient availability caused by the stratification found along the coast. However, suitable locations for kelp cultivation were also identified in areas with high vertical mixing close to the shore. The results indicate a latitudinal effect on the timing of the optimal period of growth, with the prime growth period being up to 2 months earlier in the south (58 °N) than in the north (71 °N). Although the maximum cultivation potential was similar in the six marine ecoregions in Norway (150–200 tons per hectare per year), the deployment time of the cultures seems to matter significantly in the south, but less so in the north. The results are discussed, focusing on their potential significance for optimized cultivation and to support decision making toward sustainable management.
Coastal environments of the world have been exposed to eutrophication for several decades. Recently the quality of coastal waters has been gradually and successfully improved, however the improvement has caused another issue in ecoastal ecosystem services, called oligotrophication. Local stakefolders have suggested that oligotrophication reduces pelagic productivity and moreover fishery production in coastal ecosystems, while oligotrophication with high transparency has recovered benthic macrophyte vegetation which have been depressed by phytoplankton derived from eutrophication. In particular, seagrass species is one of the most important coastal vegetation for climate change mitigation and adaptation, which has been welcomed by another stakefolders. Therefore, harmonizing coastal fishery with environmental conservation is now essential for the sustainable use of ecosystem services. Here, we just started some practice in field based on the interdisciplinary approach including ecological actions, socio-economical actions and moreover psychological actions to find the integrative coastal management maximizing well-beings of various stakefolders, which is essential to harmonize environmental conservation with sustainable fishery and aquaculture. Now we are focusing on the interaction between oyster aquaculture and seagrass vegetation as an ecological action.
The debate over Brexit and the fisheries question has focused very largely on the expected benefits for the UK's fishing industry to the virtual exclusion of potential implications for the seafood supply chain. This paper refocuses attention on a supply chain now heavily dependent on both imports and exports of fish and fish products mainly to EU markets. Brexit could pose potentially significant problems arising from the imposition of tariff and non-tariff restrictions on trade and limitation on future movements of semi-skilled and unskilled EU migrants into the UK labour market. Three elements of the supply chain are likely to be directly affected: the shellfish and small scale fisheries sectors impacted by tariff and non-tariff restrictions and perhaps most significantly the fish processing industry, similarly affected by trade restrictions and heavily dependent on EU labour. Brexit has also been the catalyst for renewed pressures in Scotland for further devolution of powers relating to the fishing industry that at some future date could see the development of two distinctive seafood supply chains within the UK.
Shellfish profession is jeopardized by water quality problem that concerns inlet, with the need to protect the animals from pathogens contaminations, and effluents potentially harmful for the environment with the presence of pathogens, nutrients or organic matter. In this study, ultrafiltration was tested to answer these issues. The objective of the work was two-fold: (i) treat a real effluent from an oyster breeding, the pilot had to continuously face a water containing organic matter and pathogens and (ii) use ultrafiltered water to feed an oyster spat. The process was proved to be efficient in terms of total suspended solids (TSS) and bacterial retention, and especially for Vibrio bacteria, some of whom are potentially harmful for shells. The sustainability of the process facing this pollution was demonstrated and thus for different filtration conditions. Indeed, backwashes and air-backwashes performed were efficient enough to control the fouling generated, so a chemical cleaning was necessary about every 12 h. Water quality parameters, physico-chemical and bacterial, of ultrafiltered effluents were similar to the one obtained with a classical seawater used to feed oyster spats. Ultrafiltration was efficient to treat an effluent from oyster farm and produce water allowing the grown of juveniles. This process could be a solution to reuse effluents in shellfish farms.
Plastic pollution is a pervasive problem to marine life. This study aimed (1) to investigate levels of microplastic in wild and farmed mussels (Perna perna), and (2) to assess the effectiveness of depuration in reducing microplastics. Wild and farmed mussels were sampled from Guanabara Bay (Southwestern Atlantic). Four treatments were compared (N = 10 mussels/treatment): wild non-depurated mussels, wild depurated mussels, farmed non-depurated mussels, and farmed depurated mussels. Up to 31.2 ± 17.8 microplastics/mussel (≥0.45 μm) were detected (means ± SD), and microplastics were present in all 40 individuals analyzed. Nylon fibers were more abundant than polymethyl methacrylate (PMMA) fragments. Blue, transparent, and red nylon fibers were more abundant in both wild and farmed mussels. Although 93 h-depuration significantly reduced microplastics (ANOVA, p = 0.02) in both wild (46.79%) and farmed mussels (28.95%), differences between farmed and wild mussels were not significant (p > 0.05). Depuration was more effective in removing blue fibers. Our results highlight the importance of depuration in reducing microplastic pollution in seafood.
Sustainability standards for seafood mainly address environmental performance criteria and are less concerned with the welfare of fisheries workers who produce the seafood. Yet human rights violations such as slavery and human trafficking are widespread in fisheries around the world, and underscore the need for certification bodies and other seafood supply chain actors to improve social performance, in addition to addressing environmental challenges. Calls for socially responsible seafood have referenced human rights law and policy frameworks to shape the guiding principles of socially responsible seafood and to provide the legal machinery to implement these aspirations, but practical guidance on how to achieve this is lacking. To provide clarity on this challenge, we reviewed the literature concerning human rights in the seafood supply chain, and prepared an analysis of opportunities and challenges to implement socially responsible seafood through relevant human rights, legal and policy instruments. We observe that human rights laws are generally framed in favour of addressing violations of civil and political rights, but there remains considerable scope for applying economic, social and cultural (ESC) rights in this context. Other challenges include weakly defined ESC rights infringements, a lack of straightforward mechanisms to enforce human rights entitlements, and practical difficulties such as resources to support and secure rights. On the positive side, governments can draw on international instruments to inspire national policies and legislation to eliminate illegalities from the seafood supply chain. However, for socially responsible seafood principles to translate into tangible actions, these objectives must be rooted in clear legal obligations and be supported by sufficient national capacity and political will.
Juvenile scallops of Pecten maximus were studied to see the capability to clear out and incorporate salmon feed and feces (30 μg L-1). Algae were also given, in a low and high concentration in addition to feed and feces, to mimic a winter and summer situation in Norwegian waters. Rhodomonas baltica and Chaetoseris muelleri were provided in a concentration of 50 μg L-1 and 300 μg L-1. The feeding trial lasted for 27 days. Clearance rate was measured to study filtration characteristics, while fatty acid profiling and stable isotopes of nitrogen and carbon were used to trace the uptake of salmon feed and feces in the digestive gland and muscle of juvenile scallops (30–35 mm shell height). The results show that the scallops could clear out and retain both salmon feed and feces particles, although at a statistically lower clearance rate than the algae. Fatty acid profiling revealed that the scallops assimilated and incorporated the consumed salmon feed and feces, given with either high or low algae concentrations, in their tissues, where the fatty acid C18:1n9 was used as a tracer fatty acid. The digestive gland of the scallops that were fed salmon feed and feces contained a higher share of C18:1n9 than those that were only fed algae. The digestive gland reflected the fatty acid composition of the diet, while the fatty acid composition of the muscle, which also changed, reflected a more complex relation between diet and metabolic processes in the tissue. The use of stable isotopes of carbon and nitrogen to trace food sources was inconclusive in this study due to low differences between samples fed different feeds. Fatty acid profiling was a more sensitive method for tracing low concentrations of salmon feed and feces in the algae diet of scallops. Our results suggest that P. maximus could be a candidate for integrated multitrophic aquaculture (IMTA) and that scallops have the potential to utilize small particles of wasted salmon feed and feces during a winter situation with low phytoplankton concentration and during an algal bloom in Norwegian waters.
The recent Marine Stewardship Council certification for the Russian Barents Red King Crab demonstrates the consequences of overlooking ecological factors in seafood sustainability assessments. The crab is commercially valuable but has uncertain invasive effects for the ecosystem. Russian authorities manage it as a long-term fishery and openly accept the co-incidental risks that come along with the invasion. The Russian crab fishery is monopolized and there is limited transparency on both quota acquisition and decision-making regarding its management. Including ecological and socio-political dimensions expands the sustainability definition to more closely match general consumer perceptions of what certified sustainability represents. The focus of widely trusted certification processes on fishery practices masks important sustainability considerations from end consumers and may distort their choices.