Feasibility of open recirculating system in temperate climate – a case study

The increasing number of depleted, overexploited and recovering world marine stocks, together with increasing demand for fish and need for sustainable management of aquatic resources has led to a gradual shift to inland intensive aquaculture with water reuse. Intensive recirculating systems are becoming a rapidly developing sector of aquaculture, with the objectives to increase production and minimize environmental impact. However, transfer of technologies from original sites to locations of different climate is not always successful. The present study evaluates the use of an open recirculating system in a temperate climate. The 3‐year study showed successful production with better fish growth and feed utilization than in a flow‐through facility at the same site, but presented significant issues necessitating changes in technology as well as physical adaptations. A positive effect of the technology with respect to the environment is possible, but systems must be adapted to temperate climatic conditions.     

Profitability and technical efficiency of aquaculture systems in pampaanga,philippines

Abstract

We evaluate the profitability and technical efficiency of aquaculture in the Philippines. Farm‐level data are used to compare two production systems corresponding to the intensive monoculture of tilapia in freshwater ponds and the extensive polyculture of shrimps and fish in brackish water ponds. Both activities are very lucrative, with brackish water aquaculture achieving the higher level of profit per farm. Stochastic frontier production functions reveal that technical efficiency is low in brackish water aquaculture, with a mean of 53%, explained primarily by the operator's experience and by the frequency of his visits to the farm. In freshwater aquaculture, the farms achieve a mean efficiency level of 83%. The results suggest that the provision of extension services to brackish water fish farms might be a cost‐effective way of increasing production and productivity in that sector. By contrast, technological change will have to be the driving force of future productivity growth in freshwater aquaculture.     

Nitrogen removal techniques in aquaculture for a sustainable production

As the aquaculture industry intensively develops, its environmental impact increases. Discharges from aquaculture deteriorate the receiving environment and the need for fishmeal and fish oil for fish feed production increases. Rotating biological contactors, trickling filters, bead filters and fluidized sand biofilters are conventionally used in intensive aquaculture systems to remove nitrogen from culture water. Besides these conventional water treatment systems, there are other possible modi operandi to recycle aquaculture water and simultaneously produce fish feed. These double-purpose techniques are the periphyton treatment technique, which is applicable to extensive systems, and the proteinaceous bio-flocs technology, which can be used in extensive as well as in intensive systems. In addition to maintenance of good water quality, both techniques provide an inexpensive feed source and a higher efficiency of nutrient conversion of feed. The bio-flocs technology has the advantage over the other techniques that it is relatively inexpensive; this makes it an economically viable approach for sustainable aquaculture.     

Review of trends in the development of European inland aquaculture linkages with fisheries

Aquaculture is a multifaceted, dynamic food production sector in Europe. The average annual growth rate of aquaculture production in Western Europe was 5.5% between 1988 and 1998, while in Eastern Europe production declined by 56% during the same period. The main growth in aquaculture production has taken place in the marine environment, particularly in the expanding salmon, Salmo salar L., industry of Northern Europe. Inland aquaculture only contributed 19% of the total aquaculture production in 1998. Trout in Western Europe, and common carp, Cyprinus carpio L., in Eastern Europe are the dominant species in inland aquaculture. Inland fisheries production has been stagnant in Western Europe and has declined considerably in Eastern Europe. The importance of recreational fisheries is increasing all over Europe, although no reliable data are available on angler catches. The major interactions between aquaculture and fisheries are pollution by untreated effluents from farms and impacts on indigenous fish stocks. The conflict is decreasing as more advanced systems are used in inland aquaculture, including water recirculation and effluent treatment. The positive benefit of aquaculture is that the sector supports extensive stocking programmes in commercial and recreational fisheries all over Europe.     

Grow-Out Production of Carps in India

ABSTRACT

Asian aquaculture has been contributing in great measure to the global fish basket. The Indian subcontinent, with a rich biodiversity of fish species, has emerged as an important aquaculture country, particularly in the freshwater environment. Carps form the mainstay of culture practices in the country, supported by a strong traditional knowledge base and scientific input in various aspects of biology, environment, nutrition, and health management. New species and culture systems, integration with other farming systems, use of organic material as nutrient inputs, and depuration measures in waste-fed culture systems are being considered for enhancing aquaculture productivity. This article presents the status of grow-out production of carps in India and traces the growth of the practices over the decades as well as the potential of the sector.     

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.     

Vulnerability of aquaculture‐related livelihoods to changing climate at the global scale

There is now a strong consensus that during the 20th century, and especially during recent decades, the earth has experienced a significant warming trend with projections suggesting additional further warming during the 21st century. Associated with this warming trend are changes in climate that are expected to show substantial spatial variability across the earth's surface. Globally, fish production has continued to increase during recent years at a rate exceeding that of human population growth. However, the contribution from capture fisheries has remained largely static since the late 1980s with the increase in production being accounted for by dramatic growth in the aquaculture sector. In this study, the distribution of vulnerability of aquaculture‐related livelihoods to climate change was assessed at the global scale based on the concept of vulnerability as a function of sensitivity to climate change, exposure to climate change and adaptive capacity. Use was made of national‐level statistics along with gridded climate and population data. Climate change scenarios were supplied using the MAGICC/SCENGEN climate modelling tools. Analysis was conducted for aquaculture in freshwater, brackish and marine environments with outputs represented as a series of raster images. A number of Asian countries (Vietnam, Bangladesh, Laos and China) were indicated as most vulnerable to impacts on freshwater production. Vietnam, Thailand, Egypt and Ecuador stood out in terms of brackish water production. Norway and Chile were considered most vulnerable to impacts on marine production while a number of Asian countries (China, Vietnam and the Philippines) also ranked highly.     

INLAND AQUACULTURE IN INDIA: PAST TREND,PRESENT STATUS AND FUTURE PROSPECTS

ABSTRACT

In India, inland aquaculture has emerged as a fast-growing enterprise and a viable alternative to the declining capture fisheries. The present paper is an attempt to assess Indian inland aquaculture with respect to its resource base, output trends, systems and activities, yield gaps, adoption and impact on aquaculturists, economics, returns to inputs, investment needs, and future prospects. The paper is largely based on existing literature and observations made as part of an ICAR-WorldFish demand supply project. Indian aquaculture is primarily limited to inland sector and carp-oriented; for that reason, this activity received special attention. Freshwater aquaculture observed tremendous growth in the past 15 years, but immense scope still exists for horizontal expansion and increases in productivity (vertical expansion). This is evidenced by the fact that the average farm fish yield is only one-third of that achieved in farm trials. The difference was mainly due to much higher input use in on-farm trials. Most of the aquaculturists were practicing extensive aquaculture, but aquaculturists with semi-intensive operations benefited most from adoption of technology. The benefit:cost ratios for different systems of aquaculture varied between 1.22 to 1.86. The return to capital was much higher than the return to labor, due to the low labor input. The semi-intensive aquaculture system would receive the greatest return from projected macrolevel investments, followed by extensive and intensive systems. Dedicated efforts are needed to meet the demand for quality fish seed and feed in order to achieve the desired 45% increase in area and greater than 50% increase in productivity. Based on the observations, activities designed to foster inland aquacultural development in India are recommended.     

Tilapia polyculture: a global review

Tilapia are the second most farmed fish worldwide and their production has quadrupled over the past decade due to ease of aquaculture, marketability and stable market prices. Tilapia aquaculture must adopt sustainable practices (such as polyculture) for continuing increased production and improved sustainability. This article reviews tilapia polyculture around the world and discusses its benefits, strategies and practices. Tilapia polyculture improves feed utilization, enhances water quality, increases total yield and profit. Further investment will increase these gains. Research on tilapia polyculture in China was also summarized and addressed that polyculture in semi‐intensive systems was a way of improving sustainability for tilapia aquaculture.     

An automated recirculation aquaculture system based on fuzzy logic control for aquaculture production of tilapia (<Emphasis Type="Italic">Oreochromis niloticus</Emphasis>)

The development of an automated recirculation aquaculture system (ARAS) is presented here. The production system facility was built in a 672-m² polyethylene greenhouse using four 20-m³ tanks, each of which was stocked with 1,000 tilapia (O. niloticus). The growth of the fish was evaluated from a starting weight of 2 g to a final average weight of 418 g, during a production cycle from July 2008 to January 2009. Our objective was to develop new technological approaches, based on fuzzy logic control, to integrate into novel automated equipment for recirculation aquaculture systems used for fish production under intensive conditions. This technique allows farmers to incorporate their knowledge and experience into the control system. The results demonstrated a substantial water savings of 97.42%. There was a total fish biomass production of 1,655.3 kg and an average feed conversion rate of 1.55. The environmental variables were kept within acceptable ranges for tilapia production. We conclude that it is possible to increase the productivity and profitability of aquaculture systems, by applying new approaches based on modern control techniques, such as fuzzy logic control, that promote resource optimization.     

Aquaculture in Egypt and issues for sustainable development

Abstract

Although aquaculture in Egypt has the potential for satisfying the increased demand for protein and has been experiencing unprecedented growth during the last decade, questions remain regarding the sustainable development of the industry. It is thus the objective of this article to review the current status and practices of the aquaculture industry in Egypt, highlighting the major issues confronting the sustainable development of the aquaculture industry.

Several issues are identified as limitations to future sustainable development, namely, production technology, fry supply, a feed industry sufficient to meet the demands of a growing aquaculture industry, and marketing and distribution systems necessary to accommodate the strong seasonal supply pattern. The article then concludes with a discussion of recommendations for alleviating these limitations.     

工厂化循环水养殖系统中流场特性与鱼类互作影响的研究进展与展望

随着人口与经济的发展,水产养殖业在世界范围内迅速兴起,集约型工厂化循环水养殖因其高密度、低污染、高效率等独特的优势,契合水产养殖业绿色发展理念,已成为水产养殖转型升级的重要方向之一。水作为循环水养殖系统中重要的环境因子,其流态能够直接影响鱼类的生长及福利,同样,鱼类存在及运动也会影响到系统流态的构建。本文综合分析了循环水养殖系统中流场条件对不同鱼类生长发育及福利的影响,鱼类及其运动行为对养殖池内水动力条件及性能的影响,以及鱼类对养殖池内流场流态、水体混合等的影响。将研究鱼类运动对流场特性的影响方法主要归纳为实测法和数值研究,通过对比分析2种方法的优点和不足之处,并结合当前循环水养殖产业系统构建中的问题提出针对性方法建议,旨在为系统中水动力条件的设计拓展思路,促进循环水养殖产业流态构建向“鱼”与“水”兼顾的方向发展。     

DISAGGREGATED ANALYSIS OF FISH SUPPLY,DEMAND, AND TRADE IN ASIA: BASELINE MODEL AND ESTIMATION STRATEGY

ABSTRACT

Quantitative modeling of fish supply, demand and trade is a useful tool for analyzing recent structural changes, such as the rapid development of aquaculture. Existing models are, however, limited by their use of highly aggregated fish categories and assumed (rather than estimated) elasticities. This paper outlines an estimation strategy and a multiproduct equilibrium model for disaggregated analysis of fish supply, demand, and trade. The model is composed of a producer, consumer and trade core, and is specified to accommodate special features of the fish sector. The estimation and modeling strategy also address common data problems, such as heterogeneity of fish types, diversity of production categories, and so forth. The model has been applied to nine major fish producers in developing Asia.     

Technical efficiency of carp production in Nepal: An application of stochastic frontier production function approach*

Abstract

Modern aquaculture is a relatively new activity among Nepalese farmers and a small contributor to the economy. Given the abundance of water resources and fish species, rising demand for fish, and its high profitability, aquaculture has potential for future expansion if it is given appropriate attention from the government. In Nepal, productivity in aquaculture is much lower compared to other countries in the region, which suggests that there is potential for increased fish production through technological progress and improvement in farm‐level technical efficiency. However, no formal analysis has yet been conducted to assess the productive performance of Nepalese aquaculture and its potential for future improvement. Against this background, this paper examines the technical efficiency and its determinants for a sample of fish pond farms from the Tarai region of the country using a stochastic production frontier involving a model for technical inefficiency effects. The estimated mean technical efficiency is 77%, with intensive farms being more efficient than extensive farms. The adoption of regular fish, water, and feed management activities has a strong positive effect on technical efficiency.     

Probiotics in fish and shellfish culture: immunomodulatory and ecophysiological responses

Aquaculture is emerging as one of the most viable and promising enterprises for keeping pace with the surging need for animal protein, providing nutritional and food security to humans, particularly those residing in regions where livestock is relatively scarce. With every step toward intensification of aquaculture practices, there is an increase in the stress level in the animal as well as the environment. Hence, disease outbreak is being increasingly recognized as one of the most important constraints to aquaculture production in many countries, including India. Conventionally, the disease control in aquaculture has relied on the use of chemical compounds and antibiotics. The development of non-antibiotic and environmentally friendly agents is one of the key factors for health management in aquaculture. Consequently, with the emerging need for environmentally friendly aquaculture, the use of alternatives to antibiotic growth promoters in fish nutrition is now widely accepted. In recent years, probiotics have taken center stage and are being used as an unconventional approach that has numerous beneficial effects in fish and shellfish culture: improved activity of gastrointestinal microbiota and enhanced immune status, disease resistance, survival, feed utilization and growth performance. As natural products, probiotics have much potential to increase the efficiency and sustainability of aquaculture production. Therefore, comprehensive research to fully characterize the intestinal microbiota of prominent fish species, mechanisms of action of probiotics and their effects on the intestinal ecosystem, immunity, fish health and performance is reasonable. This review highlights the classifications and applications of probiotics in aquaculture. The review also summarizes the advancement and research highlights of the probiotic status and mode of action, which are of great significance from an ecofriendly, sustainable, intensive aquaculture point of view.     

A survey of aquaculture production economics and management

Abstract

The literature on production economics and management of fish culture has grown as aquaculture has matured as a commercial industry. Salmon, catfish, shrimp and trout are the focus of this literature survey as a reflection of the volume of research that has been completed on these species and their importance in US production and world trade. In addition, a discussion of low resource production systems is included that is dominated by tilapia and carp culture systems. A brief overview of the principles of aquaculture production economics and management is presented followed by a review of economic studies.     

The development of the Norwegian wrasse fishery and the use of wrasses as cleaner fish in the salmon aquaculture industry

Norway leads the world aquaculture production of Atlantic salmon Salmo salar and farmed Norwegian Atlantic salmon is currently consumed around the globe. However, sea lice infestation is a major problem faced by the salmon aquaculture industry in Norway and elsewhere. The use of wild-caught cleaner fish, mainly wrasses, has been recommended over the other available methods as the most economical and environmentally friendly option to control sea lice infestation in salmon farming. Here, we review the development of the Norwegian wrasse fishery and the use of wrasses as cleaner fish. In this document, we address the sea lice problem and introduce the main wrasse species employed as cleaner fish, document the cleaning behaviour of wrasses, present the development of a new wrasse fishery associated with the salmon aquaculture industry, and finally, we identify the main challenges associated with the intensive use of wild-caught cleaner wrasses and provide some insight for future directions of the wrasse fishery and further development of aquaculture techniques to supply salmon facilities with domesticated cleaner fish.     

Fuzzy-logic-based feeder system for intensive tilapia production (<Emphasis Type="Italic">Oreochromis niloticus</Emphasis>)

In high-fish-density aquaculture systems, tilapia producers are compelled to provide 100% of food required to obtain profitable growth rates. It is well known that fish have a low food conversion rate and feeding represents the most important expenditure, approximately 40% of total production cost. Therefore, precise quantities of food should be provided to avoid water pollution and economic losses due to food waste when water conditions are inadequate for fish feeding. A way to control food provisions in this work was determined by the conditions of temperature, dissolved oxygen, fish age, and body weight, since these variables have a direct effect on fish metabolism and growth. Thus, a change in metabolism is reflected in a modification of energy requirements and, as a consequence, in variations of food consumption. In this work, a new feeder with fuzzy-logic control algorithms is proposed for fish feeding; this technique allows farmer knowledge to be taken into account in a series of if–then-type rules. To define these rules the temperature and dissolve oxygen were considered in order to provide precise food quantities. The results show minimal differences in growth (P > 0.05) between treatments, important food saving of 29.12% (equivalent to 105.3 kg), and lower water pollution (reduced water dissolved solids and ammonium components) compared with timed feeders. This system provides an important contribution to sustainability of intensive aquaculture systems, increasing productivity and profitability, and optimizing water use.     

Aquaculture development and scenarios of change in fish trade and market access for the poor in Cambodia

Aquaculture holds considerable potential to contribute to poverty alleviation, if it provides poor people with opportunities other than as primary producers. Integration of aquaculture into poverty reduction programmes provides means to diversify production systems and reduce food insecurity but also needs improved markets in locations where aquaculture can offer sustainable livelihoods to poor farming households. This study reviews the current constraints that poor people face in accessing markets in Cambodia and analyses its implications for pro‐poor domestic aquaculture development. We use a Geographic Information System‐based spatial Bayesian probability model to simulate market accessibility and estimate the numbers of poor people who could potentially benefit from improved market access under four different scenarios. Analysis of secondary data confirms that the potential for poor aquaculture producers to interact with urban markets in Cambodia is currently low. The potential of aquaculture to interact with rural markets is, however, high. It is concluded that the development of aquaculture has considerable potential to reduce the transaction costs in domestic fish trade by improved access of poor producers and consumers to rural markets in Cambodia. An aquaculture development strategy that improves rural market access could include benefits for up to 1 million poor aquatic resource users.     

Nutrition in organic aquaculture: an inquiry and a discourse

Organic aquaculture has lagged behind the agriculture sector in terms of the quantities and diversity of certified organic products because of the absence of detailed accepted standards and criteria until recently. The main challenges for organic aquaculture are to improve the coordination between production and market and to achieve an appropriate framework to drive further development. Priorities for research include organic feeds and fish nutrition, consumers’ needs, food safety, environmental concerns and trade issues. In organically cultured fish, differences in feeds and nutrition compared to conventional systems are likely to result in differences in the quality of the flesh, and this is a significant factor in consumer choice. The review covers aspects of current use of eco‐certification, formulated feeds, feed composition, aquafeed technology, sustainable alternatives to common feed ingredients, nutritional physiology and general nutritional principles and product quality in the context of the organic aquaculture. There is a future for the development of organic aquaculture but its success depends on new knowledge and technical development to meet consumers’ growing interest. The industry has to utilize the research results and update and modify the criteria and standards and thus provide high‐quality products.