Attraction and repulsion of mobile wild organisms to finfish and shellfish aquaculture: a review

Knowledge of aquaculture–environment interactions is essential for the development of a sustainable aquaculture industry and efficient marine spatial planning. The effects of fish and shellfish farming on sessile wild populations, particularly infauna, have been studied intensively. Mobile fauna, including crustaceans, fish, birds and marine mammals, also interact with aquaculture operations, but the interactions are more complex and these animals may be attracted to (attraction) or show an aversion to (repulsion) farm operations with various degrees of effects. This review outlines the main mechanisms and effects of attraction and repulsion of wild animals to/from marine finfish cage and bivalve aquaculture, with a focus on effects on fisheries-related species. Effects considered in this review include those related to the provision of physical structure (farm infrastructure acting as fish aggregating devices (FADs) or artificial reefs (ARs), the provision of food (e.g. farmed animals, waste feed and faeces, fouling organisms associated with farm structures) and some farm activities (e.g. boating, cleaning). The reviews show that the distribution of mobile organisms associated with farming structures varies over various spatial (vertical and horizontal) and temporal scales (season, feeding time, day/night period). Attraction/repulsion mechanisms have a variety of direct and indirect effects on wild organisms at the level of individuals and populations and may have implication for the management of fisheries species and the ecosystem in the context of marine spatial planning. This review revealed considerable uncertainties regarding the long-term and ecosystem-wide consequences of these interactions. The use of modelling may help better understand consequences, but long-term studies are necessary to better elucidate effects

Effects of organic enrichment on macrofauna community structure: an experimental approach

The determination of the resilience of benthic assemblages is a capital issue for the off-shore aquaculture industry in its attempts to minimize environmental disturbances. Experimental studies are an important tool for the establishment of thresholds for macrofaunal assemblages inhabiting sandy seabeds. An experiment was conducted with three treatments (Control, 1x and 3x),in which organic load (fish pellets) was added (1x (10 g of fish pellets) and 3x (30 g)). A reduction in abundance of individuals and species richness was found as between the control and organic-enriched treatments. Significant changes in assemblage structure were also found, mainly due to the decrease of the sensitive tanaid Apseudes talpa in organically-enriched treatments. AMBI and M-AMBI indices were calculated and a decrease of ecological status was observed in treatment 3x

Influence of suspended mussel lines on sediment erosion and resuspension in Lagune de la Grande Entrée, Îles-de-la-Madeleine, Québec, Canada

Downward fluxes of organically rich biodeposits under suspended mussel lines can cause benthic impacts such as changes in benthic community structure or microbial mat production. Quantifying sediment erosion in these coastal ecosystems is important for understanding how fluxes of organic matter and mussel biodeposits contribute to benthic–pelagic coupling. Critical shear velocity (u*crit), erosion rates and particle size distributions of resuspended sediment were measured at four stations distributed along a transect perpendicular to a mussel farm in Lagune de la Grande Entrée, Îles-de-la-Madeleine (Quebec, Canada). Stations were selected underneath the outer-most mussel line (0 m) and at distances of 15, 30 m and at a reference station (500 m) further along the transect. Shear velocity was measured using a calibrated portable Particle Erosion Simulator, also referred to as the BEAST (Benthic Environmental Assessment Sediment Tool). Undisturbed sediment cores obtained by divers were exposed to shear stress to compare differences between stations. Erosion sequences indicated no significant differences in u*crit between stations, but there were significant differences in erosion rates beneath mussel lines compared to other stations. Erosion rates were the highest in cores from beneath mussel lines, but paradoxically had the lowest u*crit. Mean erosion rates at u*crit varied between 25 and 47 g m− 2 min− 1 and critical erosion thresholds varied between 1.58 and 1.73 cm s− 1, which compare with intensive mussel culture sites elsewhere in eastern Canada. Significant differences existed in biotic and abiotic properties of sediments which could explain variation in maximum erosion rates within and between stations. Particle sizes measured by videography of resuspended sediment at different shear velocities ranged from 0.2 to 3.0 mm. Quantifying sediment erosion from intact marine sediments helps to improve our mechanistic understanding of these processes, and the BEAST further contributes to predictive capability in benthic–pelagic coupling modeling

Workshop on the Bay of Biscay and Iberian Coast ecoregion Aquaculture Overview (WKBoBICAO)

International audienceThe Workshop on Bay of Biscay and Iberian Coast Aquaculture Overview (WKBoBICAO) was established to assemble and synthesize aquaculture related data and information and to inform the aquaculture overview for this ecoregion.The geographic extent of the Bay of Biscay and Iberian Coast ecoregion is extensive and ranges from southern Brittany in France through northern and northwestern Spain, it includes the entire coastline of Portugal (mainland) and culminates in the Gulf of Cadiz in southern Spain. It covers a wide range of habitat types and climatic conditions, which has a bearing on the types of aquaculture practiced in the ecoregion.Aquaculture is practised throughout much of the ecoregion. Both intertidal and subtidal waters are utilized in addition to terrestrial pond culture. The aquaculture production within the ecoregion is dominated by shellfish which are largely produced in France (Oysters and Mussels) and Spain (mussels). Portugal production comprises a mix of shellfish, finfish and crustacean culture and while lower in terms of tonnage produced and value than the other countries.In 2021, the aquaculture sector in the ecoregion reached 310,000 Tons produced and €775 million in value. Shellfish are the most produced in the ecoregion and contribute to almost 75% of total value. Crustacean production in Spain and shellfish and finfish production in Portugal show a clear increase since 2010, other species are static in terms of production. Spain produces the greatest tonnage but is second to France in terms of economic value. A number of other species (e.g. finfish, polychaete worms for bait) in addition macroalgae are also grown at smaller scales throughout the ecoregion.In the ecoregion, aquaculture licencing, regulation and policy are the responsibility of the member state. While overarching policy is defined at the EU level, licensing can be different in the various countries. In Portugal a single federal body is responsible for licensing. In Spain and France, regional or local authorities are responsible for issuing licences and national approvals from relevant Ministries must be sought if public waters are to be used. It is however, acknowledged that EU legislation provides an overarching framework for important regulatory aspects including assessment and monitoring, among others, of environmental (e.g. EIA), food safety and fish health considerations. However, during licencing consultation submissions from other authorities are often required in addition to challenges presented under other legislation (e.g. Natura), which can add to the complexity of the process and lead to delays in the decision-making. Marine Spatial planning, whereby specific areas are designated for aquaculture practices, has been identified as mechanism to reduce delay of licensing decisions. Yet, conflicts with other newly developing sectors (e.g. offshore renewables) is inevitable.Monitoring of shellfish culture practices are primarily focused upon food safety considerations, e.g. biotoxin and faecal coliform analysis. In addition, all species are subject to extensive animal health regulations that are wide ranging and derives primarily from EU legislation. Some persistent issues relate to ongoing bacterial (Vibrio) infections in shellfish hatcheries and mortalities associated with pathogens (e.g. OsHV-1) during grow-out. These represent a major challenge to the industry. Poor mussel recruitment in the wild is also leading to shortages of stock for on-growing.Given the dominance of shellfish culture in the ecoregion, the primary environmental effects relate to interactions with habitats and species which might be measured via assessing ecological carrying capacity. In addition to some emerging contaminants that might affect aquaculture species, aquaculture as a source of microplastics is an increasing cause of concern. The ability of shellfish to bioaccumulate nano-plastics is also considered a risk.Small production units predominate the aquaculture sector within the ecoregion. As identified elsewhere, employment in the sector in all countries is considered modest, however, the importance of these (even part-time) roles in more isolated rural areas is acknowledged.In terms of social interactions given the historical and cultural importance of shellfish farming in the ecoregion the sector has greater social licence and as such there is more a tolerance and less challenge to this sector from the wider public. It is apparent that finfish enterprises face considerably more scrutiny during licensing and subsequently. All aquaculture sectors are challenged by decreasing water quality as a result of terrestrial activities.A number of issues are identified which may affect aquaculture development and are considered common across the ecoregion. Of particular concern are the potential effects or emerging pollutants (associated with industrial development). The impact of climate change on shellfish recruitment and disease proliferation in culture stock is also a concern

Workshop on the Bay of Biscay and Iberian Coast ecoregion Aquaculture Overview (WKBoBICAO)

International audienceThe Workshop on Bay of Biscay and Iberian Coast Aquaculture Overview (WKBoBICAO) was established to assemble and synthesize aquaculture related data and information and to inform the aquaculture overview for this ecoregion.The geographic extent of the Bay of Biscay and Iberian Coast ecoregion is extensive and ranges from southern Brittany in France through northern and northwestern Spain, it includes the entire coastline of Portugal (mainland) and culminates in the Gulf of Cadiz in southern Spain. It covers a wide range of habitat types and climatic conditions, which has a bearing on the types of aquaculture practiced in the ecoregion.Aquaculture is practised throughout much of the ecoregion. Both intertidal and subtidal waters are utilized in addition to terrestrial pond culture. The aquaculture production within the ecoregion is dominated by shellfish which are largely produced in France (Oysters and Mussels) and Spain (mussels). Portugal production comprises a mix of shellfish, finfish and crustacean culture and while lower in terms of tonnage produced and value than the other countries.In 2021, the aquaculture sector in the ecoregion reached 310,000 Tons produced and €775 million in value. Shellfish are the most produced in the ecoregion and contribute to almost 75% of total value. Crustacean production in Spain and shellfish and finfish production in Portugal show a clear increase since 2010, other species are static in terms of production. Spain produces the greatest tonnage but is second to France in terms of economic value. A number of other species (e.g. finfish, polychaete worms for bait) in addition macroalgae are also grown at smaller scales throughout the ecoregion.In the ecoregion, aquaculture licencing, regulation and policy are the responsibility of the member state. While overarching policy is defined at the EU level, licensing can be different in the various countries. In Portugal a single federal body is responsible for licensing. In Spain and France, regional or local authorities are responsible for issuing licences and national approvals from relevant Ministries must be sought if public waters are to be used. It is however, acknowledged that EU legislation provides an overarching framework for important regulatory aspects including assessment and monitoring, among others, of environmental (e.g. EIA), food safety and fish health considerations. However, during licencing consultation submissions from other authorities are often required in addition to challenges presented under other legislation (e.g. Natura), which can add to the complexity of the process and lead to delays in the decision-making. Marine Spatial planning, whereby specific areas are designated for aquaculture practices, has been identified as mechanism to reduce delay of licensing decisions. Yet, conflicts with other newly developing sectors (e.g. offshore renewables) is inevitable.Monitoring of shellfish culture practices are primarily focused upon food safety considerations, e.g. biotoxin and faecal coliform analysis. In addition, all species are subject to extensive animal health regulations that are wide ranging and derives primarily from EU legislation. Some persistent issues relate to ongoing bacterial (Vibrio) infections in shellfish hatcheries and mortalities associated with pathogens (e.g. OsHV-1) during grow-out. These represent a major challenge to the industry. Poor mussel recruitment in the wild is also leading to shortages of stock for on-growing.Given the dominance of shellfish culture in the ecoregion, the primary environmental effects relate to interactions with habitats and species which might be measured via assessing ecological carrying capacity. In addition to some emerging contaminants that might affect aquaculture species, aquaculture as a source of microplastics is an increasing cause of concern. The ability of shellfish to bioaccumulate nano-plastics is also considered a risk.Small production units predominate the aquaculture sector within the ecoregion. As identified elsewhere, employment in the sector in all countries is considered modest, however, the importance of these (even part-time) roles in more isolated rural areas is acknowledged.In terms of social interactions given the historical and cultural importance of shellfish farming in the ecoregion the sector has greater social licence and as such there is more a tolerance and less challenge to this sector from the wider public. It is apparent that finfish enterprises face considerably more scrutiny during licensing and subsequently. All aquaculture sectors are challenged by decreasing water quality as a result of terrestrial activities.A number of issues are identified which may affect aquaculture development and are considered common across the ecoregion. Of particular concern are the potential effects or emerging pollutants (associated with industrial development). The impact of climate change on shellfish recruitment and disease proliferation in culture stock is also a concern

Germline deletion of the miR-17∼92 cluster causes skeletal and growth defects in humans

Genetics of disease, diagnosis and treatmen