Elevage larvaire d'Artemia salina (Branchiopode) sur nourriture inerte: Spirulina maxima (Cyanophycee)

A technique for the intensive rearing of Artemia salina larvae (Branchiopoda) of 1 – 4 mm using the blue-green algae, Spirulina maxima (Cyanophycea) in dry powder form is described. Experimentation was carried out in a small volume (20 l) and techniques were simplified whenever possible to enable minimal handling (i.e. water is not renewed). The system is therefore easily applicable to medium and large volumes. The production requirements of Artemia salina for larval aquaculture at Centre Océanologique de Bretagne have been fulfilled by this technique since 1974 in 450-l volumes. Growth and survival rates have been satisfactory to date.Up to a certain threshold and within a given age group, the amount of food introduced influences mean population size. Under optimal conditions it is possible to rear larvae of 1 mm in 2 days, 2 mm in 4 days and 3.75 mm in 6 days. The minimal food supplies required to obtain these figures are respectively 600 mg, 1 800 mg and 4 300 mg of Spirulina powder for 10 000 larvae at the ages of 2, 4 and 6 days. These rapid growth rates are achieved by overfeeding the larvae, which results in a reduction in the size of the installations and in time demanded for culture maintenance. The use of an optimal feeding regime gives a growth rate very close to the maximum and diminishes production costs only slightly.Consequently, an optimal larval concentration per unit volume is the most economically feasible choice for a production unit. The maximum larval concentration which gave good growth and survival rates was established for an average food quantity (3 200 mg/10 000 larvae). Larval densities may reach 13 to 14 2-day-old larvae (1 mm), five 4-day-old larvae (2 mm) and two 6-day-old larvae (3.75 mm) per ml of water. To regulate the concentration of Artemia, fixed volumes of the culture are removed regularly, thus considerably increasing the production of a given tank. The weekly production of a 450-l tank is approximately 75 g of dry matter.     

DEVELOPMENT OF AN INTENSIVE SHRIMP CULTURE SYSTEM IN KUWAIT1

Development of an intensive culture system is presently being conducted in Kuwait as a means of farming penaeid shrimp in arid lands. Efficiency of commercial-scale hatchery production of Penaeus semisulcatus and P. japonicus showed significant improvement in 1981 over previous years. Three one-month hatchery rearing cycles in three 15 m³ concrete tanks yielded a total of 9.1 million post-larval shrimp with an average density of 160 PL/liter being obtained for one of these trials. Four other trials were discontinued due to low spawning rates and disease. Installation of a heat exchange system made it possible to begin larviculture in February, two months earlier than in previous years. Research in nursery and grow-out phases of intensive shrimp culture is being directed towards raceways, although Shigueno culture systems are also being investigated. Experimental work with six 18 m × 1.5 m raceways demonstrated that low water exchange rates (1 tank volume/day), combined with high aeration (9.5 liter/min) yielded the highest shrimp biomass. Unheated greenhouse structures constructed over the raceways showed that a single layer of 0.25 mm clear plastic sheeting could maintain water temperatures up to 2.7°C above those in unenclosed tanks. Rearing trials in two Shigueno tank systems demonstrated the importance of high water flow rates (3 tank volumes/day minimum) and adequate aeration. Due to sub-optimal conditions, survival was reduced to 7.5%, however, growth rates up to 6 g/month were obtained for P. semisulcatus.     

Integration of sonar and optical camera images using deep neural network for fish monitoring

Fish monitoring in aquaculture farms is indispensable for managing the growth and health status of fish resources. However, it is unrealistic to expect humans to be able to perform monitoring at night, when standard optical cameras are generally inapplicable. Although sonar systems can be used at night, their practical applications are limited by their monochrome, low-quality images. In this paper, we describe a realistic image generation system that uses sonar and camera images recorded at night. The proposed approach is based on conditional generative adversarial networks, which learn the image-to-image translation between sonar and optical images. We tested the system in a fish tank containing thousands of sardines (Sardinops melanostictus). Images were simultaneously recorded using high-precision imaging sonar and an underwater camera. Experimental results show that the proposed model successfully generates realistic daytime images from sonar and night camera images. Our system enables nighttime monitoring using sonar and an optical camera, leading to more efficient fish farming and environmental surveillance.     

Comparative analysis of flow patterns in aquaculture rectangular tanks with different water inlet characteristics

The objective of the work is to improve the design rules of rectangular aquaculture tanks in order to achieve better culture conditions and improve water use efficiency. Particle tracking velocimetry techniques (PTV) are used to evaluate the flow pattern in the tanks. PTV is a non-intrusive experimental method for investigating fluid flows using tracer particles and measuring a full velocity field in a slice of flow. It is useful for analysing the effect of tank geometries and water inlet and outlet emplacements. Different water entry configurations were compared, including single and multiple waterfalls and centred and tangential submerged entries.

The appearance of dead volumes is especially important in configurations with a single entry. Configuration with a single waterfall entry shows a zone of intense mixing around the inlet occupying a semicircular area with a radius around 2.5 times the water depth. A centred submerged entry generates a poor mixing of entering and remaining water, promoting the existence of short-circuiting streams. When multiple waterfalls are used, the distance between them is shown to have a strong influence on the uniformity of the velocity field, increasing noticeably when the distance between inlets is reduced from 3.8 to 2.5 times the water depth. The average velocities in configurations with multiple waterfalls are very low outside the entrance area, facilitating the sedimentation of biosolids (faeces and non-ingested feed) on the tank bottom. The horizontal tangential inlet allows the achievement of higher and more uniform velocities in the tank, making it easy to prevent the sedimentation of biosolids.     

Development of an innovative ring-shaped cultivation system for a land-based cultivation of marine macroalgae

Marine macroalgae become increasingly important as a regenerative source of biomass for the production of food, pharmaceuticals, cosmetics and energy. An increasing and environmentally sound utilization of algae requires a closed, land-based cultivation, not limited to coastal or offshore areas. Within this study, segmental and ring-shaped cultivation vessels were developed and compared to tumble cultivation in a circular tank. The development of these innovative approaches also considered economic efficiency, adaptability, handling and reliability. The growth rates achieved by cultivating the red algae P. palmata and C. crispus and the green alga U. lactuca over a test period of 7 d were used to evaluate these experimental models. Mean growth rates of P. palmata and C. crispus in the ring-shaped cultivation model were slightly decreased whereas growth rate of U. lactuca was similar or increased compared to tank cultivated algae. The developed ring-shaped cultivation system distinctly lowered variable costs by reducing the necessary volume of cultivation medium. An increased control of the cultivation process was achieved by separating the supply of CO₂ and nutrients, and the temperature control from agitation.     

A model to predict water temperature in plastic-covered outdoor mass algal culture systems

The design, construction and operation of a 100 m² rectangular plastic-covered culture system for green algae (chlorella, scenedesmus) is described. A simple simulation model which predicts water temperature with an accuracy acceptable for estimating algal growth rate has been developed. Although simulated and measured observations showed significant statistical agreement, the model tends to underestimate daily maximum temperature and overestimate daily minimum temperature. The model can be readily adapated for usage in other parts of the world.     

Effects of Biofilter/Culture Tank Volume Ratios on Productivity of a Recirculating Fish/Vegetable Co-Culture System

Abstract

The effects of four biofilter volume (BFV)/culture tank volume ratios (0.67/1, 1.00/1, 1.50/1, and 2.25/1) on biofilter function were examined in a recirculating fish/vegetable production system in a greenhouse. Sand beds served as biofilters, as substrate for vegetable growth, and as location for decomposition of waste solids. No fertilizer was used. Three experiments were conducted over the course of one year. In Experiment 1, as the BF V/tank volume ratio increased, total ammoniacal nitrogen (TAN) and nitrite concentrations decreased (9.0 to 3.6 mg/L and 0.39 to 0.20 mg/L, respectively), and biomass increase over the culture period and oxygen levels increased significantly (13.34 to 16.03 kg/m³ and 6.03 to 6.47 mg/L, respectively). pH was maintained at 5.8-6.2 without the addition of lime. Yield per plant of the tomato variety ‘Laura’ tended to decrease (3.4 to 2.3 kg/plant), and yield per plot increased (13.6 to 31.6 kg/plant) with increasing BFV/tank ratio. In Experiment 2, the system was operated for 42 days without plants. pH dropped rapidly to near 4.0. Cucumbers were then planted, and weekly additions of lime and CaO were made. Significantly less CaO was required to achieve target pH in systems with the largest BFV/tank ratios. pH levels conducive to good plant growth were only slowly stabilized, and cucumber yields were erratic. TAN and nitrite levels were not measured, but fish grew well (5.2 to 7.2 kg/m³ with increasing BFV/tank ratio). By Experiment 3, with the tomato variety ‘Kewalo,’ TAN and nitrite concentrations decreased from 0.96 to 0.48 mg/L and from 0.06 to 0.02 mg/L, respectively, with increasing BFV/tank ratio, and in the latter part of the experiment, pH was stabilized at 6.3-6.5 without lime. Yield/plant decreased from 5.0 to 2.4 kg/plant and yield per plot increased from 19.9 to 33.1 kg/plot with increasing BFV/tank ratio. Daily water exchanges averaged 2.8%. Nutrient concentrations of the irrigation water after a year's operation were low overall. Although plants showed no deficiency or toxicity symptoms, K⁺ was found to be low and Zn⁺⁺ high relative to other ions. No clogging was observed in the sand beds. Carbon measurements ± SEM of the sand medium at the wastewater inlet of the smallest and largest BFV/tank ratio systems were 0.23 ±0.03%, and 0.15 ±0.01%, respectively. Nitrogen was below detectable levels (<0.04%). The enhanced biofil-ter/culture tank ratios used here resulted in a functionally well balanced fish/vegetable co-culture system. While needing refinement, this design represents a step towards a highly productive, low-tech system with efficient use of water, chemical, and labor resources.     

圆柱镂空型人工鱼礁波流水动力特性数值模拟

研究人工鱼礁在波流作用下的水动力特性,对于人工鱼礁的设计具有重要的意义。基于有限体积法,采用边界造波,利用自由表面捕捉法(VOF)捕捉自由水面,建立了可以分别模拟纯波、均匀流以及波流共同作用下人工鱼礁水动力特性的多功能三维数值波流水槽。基于该数值模型对不同波流工况作用下圆柱型镂空人工鱼礁水动力特性进行数值模拟,并与物理模型试验结果进行比较。结果显示,人工鱼礁数值模拟受力与模型试验结果吻合良好,人工鱼礁所受的波流力最大值随着波高、周期和水流流速的增大而增大;人工鱼礁处于波流场波峰正下方时,背涡流的面积随着水流流速的增大而增大,随着波高、周期增大而减小。对单独均匀流作用、单独波浪作用和波流联合作用下人工鱼礁的水动力特性对比研究表明,人工鱼礁所受的最大波流力比最大波浪力、水流力都大,波流联合作用下的流场效应最显著,在礁体的后部形成了较大规模的漩涡结构。     

Genome‐wide association analysis of salmon lice (Lepeophtheirus salmonis) resistance in a North American Atlantic salmon population

Our objective was to detect single nucleotide polymorphisms (SNPs) associated with resistance to the salmon louse in the Saint John River aquacultural population of North American Atlantic salmon using estimated breeding values (EBVs) and 6K genotypes from the parent‐generation and lice count phenotypes from the challenged, but ungenotyped, offspring‐generation. In 2011 and 2012, we challenged recent smolts with approximately 100 copepodids each. Fish were euthanized once the lice reached the chalimus stages and lice count, sex, tank and salt water weight were recorded. We used a multiple trait model to estimate breeding values for the parent‐generation using their own fresh water weights and the salt water weights and lice counts of the offspring‐generation. Salmon lice count heritability for untransformed and transformed data was 0.17 and 0.29 respectively. Two different genome‐wide association study methods were compared: (i) forward multiple linear regression and (ii) a mixed linear model using principal components to correct for population stratification as implemented in the egscore function of GenABEL. The two methods detected different SNPs located on different chromosomes. The multiple regression method incorporated 70 SNPs found on chromosomes 2, 7, 9, 12, 14, 15, 21, 22, 1p/23, 24. Many SNPs entered into the forward multiple regression are likely to be false positives from not correcting for the observed population stratification and cryptic relatedness. In contrast, the mixed linear model identified only two SNPs, one on chromosome 1p/23 (6.9%) and one on chromosome 1q (6.1%) consistent with louse‐resistance being a quantitative trait.     

A continuous culture apparatus for the mass production of algae

A multi-stage, continuous culture apparatus has been designed and tested for the production of algae for larval molluscs and crustacea. A single-line system produced a maximum of 2.4 × 10¹¹ cells/day, or 5 g ash-free dry weight of Monochrysis lutheri. Multiple-line systems are recommended for hatcheries. The flow rate affected algal cell density, yield, biomass, protein level, and residual nitrate.Maximal cell yield occurred at 10 I flow per day, a dilution rate of 63% of the volume of the first growth carboy, or 30% of the volume of the total system. The system is also adaptable to growth of larger planktonic algae or mixed cultures of algae and protozoa and/or rotifers.     

Solar heating systems for recirculation aquaculture

The literature over the past 25 years indicates that there has been a continued interest in using passive and active solar technologies to reduce the conventional energy required to maintain water temperatures in small recirculation aquaculture systems. Although all of the experimental systems reviewed report favourable results, there is little information available to guide system designers. This paper describes the use of a simulation model to predict the annual conventional energy consumption of a 10.6 m³ RAS enclosed in a double layer polyethylene greenhouse in two different climates. The water was maintained at 22.5 °C and the recirculation rate was 10% of tank volume per day. Simple unglazed solar collectors have also been combined with the greenhouse to further reduce energy consumption. The effect of increasing collector area on the solar fraction and utilization of useful energy was predicted. Finally, the model was used to investigate the relationship between the occurrence of condensation on the inner cover, ventilation rates and energy use.

It was found that in a hot dry climate, the greenhouse alone was sufficient to reduce the conventional energy requirements by 87%; while in the cooler temperate climate reductions of 66% were possible. When solar collectors were added to the system, conventional energy requirements were reduced further and depended on the area of collector used. For example, in the temperate climate location, conventional energy requirements were reduced to 23% of a RAS enclosed in a non-solar building when 26 m² of solar collector inclined at the optimum angle for winter energy collection were used. Although condensation could be successfully reduced by ventilation of the greenhouse, this increased conventional energy requirements because the potential for evaporation was increased. Covering the tanks at night was found to be a more effective strategy because it reduced condensation and conventional energy use simultaneously.     

Production of second generation penaeid shrimp,Penaeus stylirostris,from Mexico

The life cycle of the penaeid shrimp, Penaeus stylirostris, was completed in captivity with the production of F₂ generation nauplii. Over one million F₂ generation nauplii were harvested from the F₁ generation represented by laboratory-reared adult shrimp. The studies were completed in a laboratory simulated, tropical environment for maturation and spawning, and in pond systems located in a temperate environment for growout of the F₁ generation.     

Water-tank experiment and static numerical analysis of the mooring system of a controllable depth cage

Recent variations in marine environments have increased the risk of aquaculture accidents at sea. This risk can be reduced by installing fish cages at the desired depth, based on environmental conditions such as wave height, the vertical profiles of water temperature, algal concentration, and dissolved oxygen concentration. Most submergible fish cages can be located at only two depths: the sea surface and a submerged depth. In the present study, a fish cage installed at various depths, i.e., a controllable depth cage (CDC), is proposed for avoiding undesirable environments. A water tank experiment is conducted to measure the drag of the cage and the static deformation of the mooring system using a scale model of the actual cage. Then, a simple numerical model based on the balance of forces on each component is developed to analyze the position and the attitude of the cage and the mooring tension of the system. The numerical model is verified by comparing the experimental and numerical results. The outcome showed that the cage and floats moved downstream at an increasing velocity. The results of the numerical simulation supported those of the water tank experiment. However, the simulated vertical positions of a cage and floats were higher compared with experimental results. Additionally, the inclination of angle increased alongside increasing velocity in the numerical simulation, whereas a complex variation was observed in the experiment. This happened because of underestimating the drag on the mooring rope in lower water current velocities; additionally, cage lift was not considered in the numerical model. Despite these discrepancies, the tension of each mooring rope was well predicted because of the dominant tension of the horizontal component. In future studies, the balance of forces on the rope should be predicted more precisely, and variations in cage drag and inclination angle should be included in the numerical model. Additionally, the effect of waves should be considered alongside water currents to ensure the safety of the CDC.     

A method for the quantification and optimization of hydrodynamics in culture tanks

A method was developed to quantify hydrodynamic mixing parameters, and to optimize the physical environmental conditions, in culture tanks. Improved mixing will result in better tank water quality, more efficient use of available volume by the culture animals (leading to optimal stocking densities and better feed management) and possibly reduced water pumping requirements. Experiments were conducted to determine the influence of a range of flow rates, residence times, water depths and stocking densities on hydrodynamics in juvenile turbot (Scophthalmus maximus (L.)) tanks. Decreases in water depth resulted in significant improvements in mixing and the efficiency with which the water was used, as indicated by reductions in dead volumes. A depth of less than 9.4 cm at a flow rate of 2 l min^–1 was expected to minimize dead volumes in the tank. This indicated that mixing was better in shallower tanks. Within the range 0–13 l min^–1, increased flow rate improved mixing at a constant depth of 9 cm (and water volume of 18.54 l) though increased flow rates greater than about 2.5 l min^–1 produced only small improvements in mixing. Within the range 0–50 fish per tank (equivalent to a mean stocking density of 0–1.84 kg m^–2), stocking density did not significantly influence mixing in tanks with a depth of 9 cm and flow rate of 2 l min^–1. Such depth reductions, for demersal species, may be a useful means to either decrease water use without reducing residence time, or alternatively to increase the flushing rate without increasing water use, at a given stocking density. The large changes in the efficiency with which the tanks were used, which were achieved with ease, indicates that attention to water mixing can give positive benefits to a wide range of land-based farm operators. Care must be taken when adjusting tank hydrodynamics, that water quality is maintained and that biological parameters such as stress levels, sunlight effects and feed management are optimal.     

基于流态的方形圆弧角养殖池进水系统优化数值研究

为研究进水系统优化对方形圆弧角养殖池内流场特性的影响,实验运用计算流体动力学仿真技术(CFD)构建方形圆弧角养殖池的三维数值湍流模型,单管进水系统设置在养殖池弧壁的中间位置(以下称弧壁单管),并主要对不同进径比(参数C/B,射流管中心位置到养殖池壁的水平距离C与养殖池短边边长B之比)和不同射流角度对养殖池系统内的流场特性开展研究。结果显示,不同进径比条件下,随射流角度增加养殖池水体平均速度均呈现先增大后减小的趋势,且最优射流角度不同。进径比为0.01且射流角度为45°时,养殖池内部流场平均流速最高。进径比为0.03时,最优射流角度为30°。当C/B=0.05～0.13时且射流角度为25°时,水体平均速度最高且流场均匀性较好。进径比C/B=0.07～0.09、射流角度为25°时,养殖池内部流态总体上优于其他工况。研究表明,养殖池流场特性与进水系统进径比和射流角度密切相关。研究结果可为工厂化循环水养殖进水系统设计和优化养殖池系统的流场特性提供理论依据。     

进径比对矩形圆弧角养殖池水动力特性影响

为研究单管入流模式下,进径比(参数C/B,C为射流孔位置到养殖池壁的水平距离,B为养殖池短边边长)对单通道矩形圆弧角养殖池系统水动力特性的影响,实验运用计算流体动力学仿真技术构建单通道矩形圆弧角养殖池三维数值计算模型,应用平均流速、阻力系数和速度分布均匀系数等流体动力学特征量分析养殖池内(尤其是池底)的流场形态,并修正能量有效利用系数以评估养殖池系统的能量有效利用率。结果显示,将进径比参数C/B从0.00增大到0.05可有效改善养殖池内流场特性,进径比参数C/B设置在0.02～0.04之间有利于单通道矩形圆弧角养殖池系统获得最佳的流场条件。研究表明,进径比参数的较小优化可显著提高养殖池内平均流速与能量有效利用率,利于形成均匀稳定的流场。     

Analysis of juvenile tuna movements as correlated random walk

We explore how a stochastic model provides the most promising avenue towards predicting fish movement. To construct a stochastic model describing fish movement, trajectories of ten juveniles in a water tank were analyzed from a stochastic point of view. The heading angle was defined as a random variable. Our analysis found that the most probable forward heading angle was between 0° and 22.5° (probability ~78%), followed by angles between 22.5° and 45° (probability ~10%). We also found that the choice of future heading angle depends on the current heading angle. Therefore, we treated heading angle state as a first-order Markov process and constructed a correlated random walk model describing juvenile movement in a water tank. Our stochastic model simulated a trajectory similar to observed trajectories. We used the model as a tool for estimating the probability distribution of potential fish path outcomes. We derived the distribution of potential outcomes from a large number of simulations (N = 1000) and investigated these trajectories. We collected a set of juvenile trajectories that collided with the tank and estimated the probability of juvenile collisions with the tank.     

不同工作姿态下立式双曲面网板水动力及周围流场特性研究

网板是单拖网中实现网具扩张的重要属具,其稳定状态直接决定拖网网口扩张程度,进而影响渔获效率和经济效益。该研究以立式双曲面网板为研究对象,利用水槽模型试验和数值模拟(Computational fluid dynamics,CFD)探究立式双曲面网板在不同倾斜状态(内、外倾斜,前、后倾斜)和冲角下的水动力性能变化,并对网板周围流场和表面压力进行可视化。结果显示:1)模型试验和数值模拟的网板升力系数均在倾角为0°,冲角为25°时达到最大值,分别为1.69和1.88;而两者的阻力系数均随倾角增大逐渐减小。2)模型试验和数值模拟的升阻比均随倾角增大逐渐减小;当内倾角为5°时,两者的升阻比均达到最大,分别为3.27和3.69。3)压力中心系数Cpb随倾角变化基本保持不变;但当网板处于前倾状态时,Cpc随倾角增大而增加;而网板处于后倾状态时,Cpc随倾角增大逐渐减小。4)CFD结果显示,网板中心面后部旋涡随倾角增大逐渐减小;当网板处于内、外倾状态时,前端流速衰减区随倾角增大逐渐增加;但当网板处于前、后倾状态时,衰减区随倾角增大逐渐减小;网板处于前倾状态时,压力中心随倾角增大逐渐向网板上端翼弦移动,网板处于后倾状态时则出现相反结果。研究结果可为今后研究网板稳定性和合理使用及调整网板提供科学参考。     

An assessment of the economic contribution of EU aquaculture production and the influence of policies for its sustainable development

This review paper examines the structure of the EU aquaculture sector, the contribution it makes to the EU economy and the policy environment for past and future development. The primary analysis uses statistical data from the Food and Agriculture Organization of the United Nations which has been re-categorized according to species groups established by the European Aquaculture Technology and Innovation Platform (EATiP) and by culture system type using expert knowledge. Additional data sources for the analysis include the European Market Observatory for Fisheries and Aquaculture Products (EUMOFA) and the European Commission Scientific, Technical and Economic Committee for Fisheries. EU aquaculture production was 1.34 million tonnes in 2012 with a first sale value of €4.76 billion. Shellfish comprised 45 % by volume and 28 % by value; marine fish 30 % by volume and 53 % by value; and freshwater fish 25 % by volume and 19 % by value. The total production volume has actually fallen slightly from 1.4 million tonnes in 2000, whilst the value has increased significantly from 2.79 billion in 2000, mainly due to a growth in Atlantic salmon production. Five countries accounted for around 78 % of the direct output value of EU aquaculture in 2012, the UK, France, Greece, Italy and Spain. Around 50 % of the direct output value was generated using marine cage systems (28 % by volume), whilst less than 3 % of value was generated in recirculated aquaculture systems (<1.5 % by volume). Around 5 % of value was contributed by extensive to semi-intensive inland and coastal pond systems. STECF (2014) estimates there are between 14,000 and 15,000 aquaculture enterprises in the EU employing around 80,000 people, approximately 40,000 full-time equivalent (FTE). The greatest number of jobs (FTE) is provided by the freshwater pond and suspended shellfish sectors due to much lower productivity figures. This could be seen as a social benefit in rural and coastal regions, but corresponding low wages could also discourage young entrants to the industry and lead to dependency on migrant workers. Where efficiencies can be improved through capital investment there is likely to be significant scope for consolidation of ownership as can be observed in the marine fish sector. The output from aquaculture has to find a place within the wider fish and seafood market where volumes are generally inversely related to price. The potential growth of the sector is therefore constrained both in relation to the overall market and with respect to competition from substitute products. These include product from EU capture fisheries as well as imports from third countries (sourced from aquaculture and capture fisheries). Whilst interactions between individual products can be hard to demonstrate, any increase in production costs is likely to lead to lower output volumes, whilst improvements in production efficiency can lead to increased output volumes. With around 60 % of EU fish and seafood supply obtained through imports, and little prospect of increasing outputs from capture fisheries, EU policy is generally supportive of sustainable aquaculture development for reasons of food security and economic development. The underlying basis for this is maximizing the quality and health benefits of farmed products, whilst improving resource efficiency and minimizing impacts. This is expressed through funding support for research and technological development and structural funds to the fisheries and aquaculture industries. However, constraints to growth also exist in the form of regulatory barriers and costs that reduce industry competitiveness. Changing market requirements are also a factor. Prospects for growth have been assessed using the results of EATiP stakeholder workshops combined with the analysis of the sector by system type. These suggest an overall increase in production by 55 % is possible by 2030 based mainly on expansion of marine cage-based farming using larger systems in more exposed sites and similarly shellfish farming using larger-scale suspended systems. Expansion of recirculated aquaculture systems appears likely based on entrepreneurial and European policy for research and technological development activity, although constrained by currently low competitiveness.