Systems Approach to Aquaculture Management

[1]Michael Phillips1, [2]Claude Boyd2 and (3)Peter Edwards3

[1]Network of Aquaculture Centres in Asia-Pacific (NACA), Department of Fisheries, Kasetsart University Campus, Ladyao, Jatujak, Bangkok 10900, Thailand
[2]Department of Fisheries and Allied Aquacultures,
Auburn University, Alabama 36849, USA
(3)Asian Institute of Technology, P.O. Box 4, Klong Luang,
Pathumthani 12120, Thailand

Phillips, M.J., Boyd, C. & Edwards, P. 2001. Systems approach to aquaculture management. In
R.P. Subasinghe, P. Bueno, M.J. Phillips, C. Hough, S.E. McGladdery & J.R. Arthur, eds. Aquaculture in the Third Millennium. Technical Proceedings of the Conference on Aquaculture in the Third Millennium, Bangkok, Thailand, 20-25 February 2000. pp. 239-247. NACA, Bangkok and FAO, Rome.

ABSTRACT: The topics covered in the Conference on Aquaculture in the Third Millennium, from highly technical sessions on genetics and feeds, to non technical policy sessions on the role of different stakeholders and institutions, reflect the wide range of factors and issues relevant to modern-day aquaculture development. The “systems approach” recognizes the diverse factors affecting aquaculture and is a multifactorial and multidisciplinary approach that attempts to analyse how different factors affect aquaculture and develop solutions to problems based on an understanding of how aquaculture systems operate. The systems approach is fundamentally a multidisciplinary approach that can be used to solve problems and identify opportunities for development. This analytical approach has been shown to contribute to identification of key research issues, development of better management solutions, improvement of business efficiency, design and testing of new aquaculture systems and more effective extension and education, among others. This paper discusses the systems approach to aquaculture, provides examples of the relevance and use of the approach in aquaculture development, and recommends areas for further study and follow up actions.

KEY WORDS: Aquaculture Management, Systems Approach, Aquaculture Development, Asia




Introductory remarks

The varied topics covered in these Proceedings of the Conference on Aquaculture in the Third Millennium, from highly technical sessions on genetics and feeds, to nontechnical policy sessions on the role of different stakeholders and institutions, reflect the wide range of factors and issues relevant to modern aquaculture development.

The “systems approach” recognizes this diversity of influences on aquaculture development, and is a multifactorial and multidisciplinary approach. It uses an understanding of how aquaculture systems operate to analyse how different factors affect aquaculture and develop solutions to problems that are identified. This analytical approach has been shown to contribute to identification of key researchable issues (Edwards, 1998; Smith, 1999), development of better management solutions, improvement of business efficiency, and design and testing of new aquaculture systems, as well as to more effective extension and education.

The analysis and understanding of aquaculture systems can occur at different “levels”:

  • the organism and its surroundings;
  • the production unit;
  • the economic enterprise;
  • the farm, watershed or coastal areas;
  • the national sectoral level, or even
  • the international level.

The boundaries chosen for the system of interest may be physical entities, political borders or organizational structures. In terms of this paper, the focus is on the following systems: the farm; the farm and its local environment; and the national level, recognizing the fact that there are critical interactions between these different levels.

This paper is intended to be complementary to the earlier papers in this technology session which focused on the individual components of the system – such as feed and nutrition, health, seed and genetics – and emphasises understanding of how these individual components interact within the wider context of aquaculture systems. It first looks at our current understanding of aquaculture systems and management strategies based on a systems approach, with an emphasis (as in this session) on farm-level management practices.

  As social, economic, policy and institutional issues are all important – at some level – in a systems approach, the paper also provides a link between the Conference’s farming technology and policy sessions and closes with some suggestions for discussion on future directions. This paper was developed from discussions and contributions made by panel members and participants during the Conference on Aquaculture in the Third Millennium. The recommendations presented here represent a consensus of recommendations adopted in the final plenary session of the Conference.

Aquaculture systems and sustainability

Sustainable development and sustainability are complex issues that are difficult to define and apply to aquaculture. The “systems approach”, however, can assist understanding of these issues, as they relate to aquaculture development.

The term sustainability has been defined in various ways but perhaps the most widely used is based on the definition of “sustainable development” in the Brundtland report: “sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs”. An even more succinct definition is that of the International Union for the Conservation of Nature (IUCN): “sustainable development improves people’s quality of life within the context of the Earth’s carrying capacity”. These definitions contain two key concepts: meeting the present and future needs of the world’s people, and accepting the limitations of the environment to provide resources and to receive wastes for the present and for the future. The Food and Agriculture Organization of the United Nations (FAO), in particular, recognized that increased capacity at the national level is required to achieve sustainable development by including the need for “institutional change” in definitions of sustainable agricultural development (FAO, 1995). The recognition that institutions are important highlights the need for education and training, effective institutional arrangements and a legal and policy framework to underpin sustainable development of agriculture, and indeed aquaculture.

Sustainability is commonly split into three separate components: social sustainability (SS); economic sustainability (EcS); environmental sustainability (ES). Whilst social sustainability criteria are difficult to define, the definition of economic and environmental sustainability are providing a basis from which management options can evolve in aquaculture projects.




To take sustainability to a more practical level requires consideration of environmental, social and economic issues in aquaculture development. Thus, the approach to sustainability implies a systems approach.

There are general guidelines available on the different issues to consider. The Code of Conduct on Responsible Fisheries (CCRF), adopted by the FAO Conference in 1995 (FAO, 1995) in particular, identifies a number of key issues. The Code sets out principles and international standards of behaviour for responsible practices, to ensure effective conservation, management and development of living aquatic resources while, at the same time, recognizing the nutritional, economic, social, environmental and cultural importance of fisheries and aquaculture, and the interests of all those involved in these sectors. The Code’s Article on Aquaculture Development (Article 9) contains provisions relating to aquaculture, including culture-based fisheries. Fundamentally, the Code recognizes the importance of activities that support the development of aquaculture at different levels:

  • the producer level;
  • the local area, i.e., the farm and its integration into local area management and rural development schemes;
  • the national institutional and policy environment; and
  • international and transboundary issues.

The Code identifies many key principles in development of management strategies based on an understanding of aquaculture systems – from the farm to national and international levels. It also provides a basis for a systems approach.

The systems approach

Farm level

There is a lot of information on aquaculture farming systems, and various definitions are available, such as the level of intensity of management and output, and degree of integration with other on-farm activities. A considerable literature exists on integrated (agriculture-aquaculture and vice versa) farming systems (Edwards, 1998 and “Farming species and systems” in these proceedings).

  However, there are a wide range of culture species, culture facilities and management practices in use, and thus a very wide range of farming systems.

Key factors to be understood in the functioning of a farming system are the technologies of production and social, economic and environmental aspects. At the technology level, feeds, feed additives and fertilizers, water quality, seed quality and availability, chemoterapeutants and other chemicals, disposal of wastes that may adversely affect human health and/or the environment, and food safety of aquaculture products all require consideration. It has also been emphasised that a better understanding of the microbial populations in aquaculture systems, their interaction with the health of the farmed animals, and their role in maintaining a healthy aquatic environment are required.

The systems approach at the farm level can be used to understand and improve the efficiency of use of key natural resources – particularly water, nutrients, land, seed and financial resources. When focussing on the mix of all sustainability criteria through a systems approach, we have to deal with such factors as: appropriate densities, production and husbandry systems geared to the animal’s health, maintaining ecological balance within the pond or other growout habitat, and provision of optimal social and economic benefits. It is inevitable that impacts on natural resources will become an increasingly important issue in the new millennium, and the systems approach can be used to analyse and develop the solutions required for more sustainable use of natural resources.

A wide range of management systems is already employed in aquaculture operations with varying degrees of success. Given that aquaculture systems range from small, relatively self-contained farms for subsistence, to large-scale commercial units for trade purposes, variable success is hardly surprising. Thus, a “one-size fits all” approach is unlikely to be successful. A systematic approach to production management, however, allows the farmer to manipulate and control production inputs that will result in more efficient, cost-effective production and minimize excessive outputs with negative environmental impacts. There is a tremendous body of information on site selection, farm construction and design features, aquatic animal health management, broodstock and seed production and care, production techniques, the use of appropriate feeds, feed additives and fertilizers, water and sediment management, including effluent control, and other topics (e.g., Chanratchakool et al. 1998; FAO/NACA, 1995; Pennell and Barton, 1996).




The challenge is to optimize dissemination and use of such information and experience.

The systems approach can also be used for aquatic animal health management. Here the emphasis needs to move more towards management procedures, policies and products that can prevent or effectively eradicate significant pathogens, prevent re-infection through contaminants, and manage diseases in an environmentally sustainable manner. Subasinghe et al. (1998) provide a discussion of the role of the systems approach in aquatic animal health management.

The local level

The systems approach at the local level recognizes that individual farms cannot be seen in isolation, and that there are many interactions between an aquaculture farm and the external environment – including environmental resources and local communities. Furthermore, there can be significant cumulative effects where there are large numbers of farms crowded in small areas.

Environmental interactions with aquaculture arise from a wide range of inter related factors including availability, amount and quality of resources; type of species cultured; size of farm; culture systems management; and environmental characteristics of the farm location. Environmental interactions are not limited to impacts of aquaculture on the environment, but include environmental impacts on aquaculture and impacts of aquaculture on aquaculture. Perhaps less well known or documented are the many ways that aquaculture can contribute to environmental improvement, for example mollusc farms’ desedimentation or improved nutrient turnover (Hatcher et al., 1994), or water storage on small-scale freshwater farms.

At the local level, social and institutional interactions are also important and need to be better understood, for example:

  • participation of, and benefits to, rural communities;
  • institutional support through extension services;
  • access to information etc.

A systems approach attempts to understand these linkages and develop management strategies based on such understanding.


The future of integration of aquaculture into local ecological and social systems requires more focus on local area development planning. Fortunately, increasing attention is being given to such issues, particularly in coastal areas. Integrated coastal management (ICM) is a process that addresses the use, sustainable development and protection of coastal areas, and according to GESAMP (1996) “comprehensive area-specific marine management and planning is essential for maintaining the long-term ecological integrity and productivity and economic benefit of coastal regions”. ICM is made operational through such activities as:

  • land use zoning and buffer zones;
  • regulations, including permitting to undertake different activities;
  • nonregulatory mechanisms;
  • construction of infrastructure;
  • conflict resolution procedures;
  • voluntary monitoring; and
  • impact assessment techniques.

More participatory approaches to planning of aquaculture development will also be given attention with the move towards integrated development planning (see S. Sen, this volume). Practical experience in implementation ICM for aquaculture is limited, which is in large measure because of the absence of adequate policies and legislation and institutional problems, such as a lack of unitary authorities with sufficiently broad powers and responsibilities, as well as limited training and education of people concerned.

In inland rural areas, increasing attention is being given to integration of aquaculture into rural development and special area management plans. Increasing emphasis is also being given to promotion of aquaculture for poverty alleviation (see Haylor and Bland, this volume). Such an approach requires emphasis on immediate social needs and people’s livelihoods (and how aquaculture might meet these needs and contribute to improved livelihoods) rather than a technology/aquaculture driven approach. The emphasis on aquaculture for development, rather than development of aquaculture may lead to some fundamental changes in the approach to promotion of aquaculture in the coming years.

National, regional and international levels

At the national level, government policy, and institutional and human capacity are most important in providing a strong foundation for aquaculture to develop in a su (Insull and Shehadeh, 1996).




These issues are covered extensively in the Conference’s policy session and are not discussed in detail here, except by recognition that most community and farm activities are influenced by national-level policy, legislation and institutional support. For example, the level of aquatic animal disease affecting small-scale producers or enhanced fisheries is related to national policies for quarantine and movement of live aquatic animals, which affect the risk of exposure of small-scale producers to serious aquatic pathogens (DFID/FAO/NACA/GoB, 2001). Inter- and intra-country trading patterns and movement of aquatic animals also affect these risks. International conventions (e.g. the Convention on Biodiversity), trade and consumer preferences, all clearly impact aquaculture development at a local level.

Application of the systems approach

Some examples of systems approaches presented during the Conference are given below.

Small-scale farmer research and extension

The systems approach has been widely used in the promotion of sustainable development through small-scale integrated aquaculture (Edwards, 1998). He emphasises that most scientists focus on technical aspects of aquaculture, resulting in the impression that the major constraint facing aquaculture development is a shortage of technical knowledge, overshadowing the developmental and educational constraints. The most important constraint to aquaculture development is dissemination of existing knowledge, whether derived from research or indigenous technical knowledge of farmers also affect these risks. The limited capacity of developing-country institutions in education, research and development compounds this fundamental failing. Research should follow farming systems research and extension methods in which inter-disciplinary teams work with farmers to evaluate and develop both production systems and extension methods that are appropriate to the local conditions of farmers and their resource base.


  A systems approach to management has more potential for success on the typically diverse small-scale farms in developing countries. This approach includes analysis of the resource-base of the farm, and the farmers’ perceptions of their needs. The role of institutions in promoting the development of aquaculture can also be analysed using such an approach. The role of national institutions (government and non governmental agencies) as primary facilitators of aquaculture and the necessity of capacity building in order to facilitate the systems development approach should be recognized. International and regional agencies can support such capacity building.

Environmental management systems

Environmental management systems are also starting to evolve for some forms of aquaculture, as well as more formal environmental management systems (EMS). EMS is a complex approach with little direct application to small- and medium-sized farms, however, EMS principles provide useful guidance for improving environmental management of aquaculture production systems (H. Dixon, pers. comm.).

EMS assemble management policies, programmes and practices designed to identify links between industry, urban and developmental activities, and consequent pressures on the environment. An effective EMS for aquaculture should establish indicators of changes in the environment, including land, water and aquatic resources. Policies and practices responding to the changes are implemented with continuous feedback to reduce/mitigate any environmental impacts. These indicators should make clear links between environmental impacts and aquaculture activities. The indicators should also reflect positive and negative impacts of environmental influences on aquaculture, as well as visa versa.

EMS provides a possible systematic approach to motivate aquaculture to better organize priorities and projects to identify problems and potential impacts before they occur, as well as meet environmental and business goals. This process also assists compliance with national environmental laws and regulations. A successful EMS provides the means by which aquaculture can identify causes of environmental problems and prevent them, thus saving money to repair or mitigate after the damage has been done.




According to H. Dixon, key benefits of an EMS include:

  • improved environmental performance,
  • reduced liability,
  • competitive advantages,
  • improved compliance,
  • reduced operational costs,
  • enhanced consumer trust, and
  • increased access to capital.

H. Dixon considers that formulating an institutional framework for environmental management systems of aquaculture should:

  • be simple to implement, clear and comprehensible to all involved, including the public;
  • consider the needs of all stakeholders;
  • consider individual abilities and resources;
  • be financially flexible and not inhibit the activities it is designed to address; and
  • be based on sound scientific information, quantifiable and effective.

Codes of Practice

The technical methods, management systems and practices needed for minimizing impacts are being increasingly incorporated into more formal “Codes of Practice”, notably in more commercially oriented and intensive shrimp and salmon farming. Several aquaculture organizations, for example, the Marine Shrimp Culture Association of Thailand, the Global Aquaculture Alliance, the Australian Prawn Producers Association, the Irish Salmon Growers Associations and others have taken the FAO Code of Conduct a step further and formulated Codes of Practice (COP). These COP contain principles for preventing or mitigating negative environmental and social impacts through use of “best management practices” (BMP). They are currently for voluntary adoption and consist of documented guidelines available to farmers. Much needs to be done towards their implementation, such as the development of operational manuals and support programmes. Furthermore, the extent to which COP will be fully adopted by farmers under self-regulation and the environmental consequences of their adoption remain to be determined. Implementation is a very important issue for the new millennium, particularly for small-scale farmers.

Improving profitability of aquaculture operations

The systems approach is directly applicable to the business of aquaculture, through the use of a structured, systematic approach to operations and business management.

  E. Hempel considers that in high technology salmonid aquaculture, the “software” of aquaculture (people) is more important than the hardware or “technology”. There are many facts and variables, so in order to understand and manage the system, things have to be simplified – “systematized” –. The approach emphasised by E. Hempel involves:
  • understanding and identifying the system of concern within the farm enterprise/business;
  • simplifying the system by identifying only key system variables;
  • for each person working at different levels of the organization, identifying the key system variables to monitor;
  • reducing the number of variables to the minimum – e.g. dissolved oxygen, food conversion ratio (FCR), cash flow, and set limits/standards; and
  • monitoring and responding to changes that exceed the set limits.

E. Hempel also emphasises that effective management based on a systems approach requires assigning of responsibilities within an aquaculture business to monitor and respond to changes that occur. He also emphasises that the system may change with time, and that management has to be flexible to respond to such changes. He further considers that the systems approach to business and management is important to improving the performance and profitability of farming, and is relevant at all levels of aquaculture, from small-scale farms to the largest business.

Institutional use of a systems approach

A systems approach can also be used to define institutional responsibilities in aquaculture. For example, in western Australia, according to C. P. Rogers’ presentation during the “Systems session” of the Conference on Aquaculture in the Third Millennium, NACA/FAO, 2000) a systematic analysis of institutional responsibilities was useful to establish the key points for decision making in allocation of land and water resources for aquaculture development. This helped streamline permit processing. He also emphasised that a systematic evaluation of management processes can be valuable in identifying institutional responsibilities at both government and private-sector levels, as well as for promotion of small-scale aquaculture.




Implications of systems approach for future aquaculture development

Aquaculture can be socially, environmentally and economically sustainable and, contribute to the production of food and rural development, provided appropriate farming systems and management practices are adopted.

The multidisciplinary and multisectoral systems approach recognizes that technical, economic, social and environmental issues, as well as institutional factors, have to be considered in the process of development and management of aquaculture. The systems approach attempts to understand the way the system operates and the interactions between different components, and serve as a basis for better management. This multidisciplinary approach requires different skills and, as such, also needs cooperation among different disciplines and information exchange among different stakeholders. The application of a systems approach to aquaculture has several implications for a more analytical and structured approach to aquaculture development.

There is a need for better information on aquaculture systems and promotion of more effective information exchange between stakeholders. Information requirements include social and environmental interactions at the farm level, development of better practices targeting important environmental and social impacts, and seeking incentives for farmers to adopt better farming practices.

Development of suitable indicators is also another important factor. For assessing natural resource use by aquaculture, recent research has emphasised the “ecological footprint” (Kautsky et al., 1997). The aims of the authors to develop a “sustainability” index are to be commended, however, there are a number of problems with the models promoted so far (Roth et. al., 2000), including:

  • their static and dimensional (area) nature;
  • the difficulties of incorporating economic and social values into the approach;
  • the emphasis on biophysical factors;
  • the lack of the footprint and ecological capacity to accept multisectoral or multiple uses;
  • the lack of inclusion of ecosystem services (such as absorption capacity for discharge of nutrients into coastal ecosystems); and
  • difficulties in making comparisons between different locations and systems.
  There was a consensus in the Conference discussions on the need to develop and evaluate meaningful indicators of resource use efficiency to better define environmental interactions with aquaculture and improve management decisions. Research is required to develop and evaluate meaningful indicators of resource use efficiency useful to management decisions.

Institutional strengthening in the private and public sectors is another critical issue that must be addressed. The systems approach recognizes that national institutions (government and non governmental agencies) are the primary facilitators of aquaculture development in their countries. However, national institutions involved in the promotion of aquaculture need to increase their capacity and reinforce emphasis on multidisciplinary approaches. This will require a shift away from traditional “top down” and “technology focused” capacity building and extension approaches, towards an approach that is interactive and responsive to farmer needs.

As emphasised above, much aquaculture research to date has focused on technical questions, leaving the impression that the major constraint facing aquaculture is a shortage of technical knowledge. This detracts from the attention needed for development and basic aquaculture education (Edwards, 1998). Another important constraint to aquaculture is dissemination of existing knowledge, whether derived from research or the indigenous technical knowledge of farmers. The limited capacity of many developing countries’ national institutions in education, research and development concerning the promotion of aquaculture compound this problem, and require serious attention in the new millennium.

Examples of the systems approach mentioned during the panel discussions included:

  • its application to small-scale farmer research and extension;
  • the development and application of best management practices to improve environmental management on commercial aquaculture farms;
  • improving the profitability of aquaculture operations through the use of a structured, systematic approach to operations and business management; and
  • the institutional use of a systems approach to assist in effective decision making at a regulatory/planning level and within the aquaculture industry as a whole.




Recommendations of the Bangkok Conference

The following recommendations were adopted by the Millennium Conference:

That a multidisciplinary and multisectorial and systematic approach be taken in the development of aquaculture and aquaculture research. Applying a systems approach allows the proper understanding and analysis of problems and opportunities, and the development of solutions based on the understanding of how systems operate. The systems approach involves basically seven steps:

  • state the problem;
  • identify the system;
  • classify and describe the system, boundaries and key factors;
  • analyse the problem;
  • propose solutions;
  • test the solution; and
  • implement and disseminate knowledge to solve the problem.

Codes of Practice, and the Best Management Practices incorporated into such codes offer an opportunity to improve management. These need to be developed further and applied in real situations as a practical basis for the operating system. Special attention needs to be given to:

  • implementation of Codes of Practice;
  • the need for continual fine tuning to take account of new information and technology;
  • a role for farmers in implementation (there should be greater participation by farmers and other end-users to provide feedback and fine-tune systems management practices); and
  • the effectiveness of self-regulation.

There was a consensus on the need to develop and evaluate meaningful indicators of resource use efficiency to assist in understanding environmental interactions with aquaculture and improve management decisions. The use of the “ecological footprint” model as a tool was discussed, and it was suggested to develop a more appropriate index.

There should be more emphasis on multidisciplinary research using a systems type approach, to better understand problems and opportunities and develop more appropriate solutions to overcome aquaculture development constraints and unfulfilled potential.

  There is a need to communicate practical examples where the systems approach has been used and to incorporate the problem identification and solving systems approach into educational and training programmes.


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