aquaculture

According to William A. Wurts from the Kentucky State University, Cooperative Extension Program, Sustainable Aquaculture in the Twenty-First Century (a .pdf download – Reviews in Fisheries Science, 8(2): 141-150 (2000)) people have approached sustainability from three perspectives: environmental, economic, and sociological. Wurts notes in the abstract:

Ultimately, sustainability may be the aquaculture industry’s ability to adapt on a planet with an ever increasing human population which continues to consume its limited supply of non-renewable resources at an alarming rate.

Although ever increasing costs of resources such as oil and water continue to apply pressure to the development of sustainable models across all spectra of human endeavor, the discussion around sustainable aquaculture is not exactly new. Sustainable Aquaculture Development and the Code of Conduct for Responsible Fisheries was presented by William D. Dar to the FAO, Rome in March 1999.

Sustainability is also not just a concern of aquaculture – the broader concerns of ocean governance has also been considered by George Pararas-Carayannis in Ocean Governance and Sustainability – Present Trends – Future Challenges. From the abstract:

The ability of marine ecosystems to produce the economic and ecological goods and services that are desired and needed, have been substantially reduced. In some instances there has been a significant decline of ocean wildlife and even collapses of ocean ecosystems. It is clearly evident that what we once considered to be inexhaustible and resilient is, in fact, finite and fragile.

Patrick Sorgeloos offers comment regarding Technologies for Sustainable Aquaculture Development. From the introduction:

Risks of major environmental and human-health problems need to be weighed against achieving a more cautious rise in production that is, in the longer term, sustainable. We should all see this not only as a challenge to do it well and responsibly, but also as a commercial opportunity for the industry.

Aquaculture is clearly at a crossroads and can come, in fact, should come of age in the twenty-first century. However, this will require more responsible researchers and more integrated R&D approaches than we apply at present.

Denis Bailly and Rolf Willmann have provided research findings entitled Promoting Sustainable Aquaculture through Economic and other Incentives. From the abstract:

Economic incentives have been widely applied to encourage growth in aquaculture production, especially in the “infant” phase of development where risks are often high and scale economies cannot yet be realized. In recent years, increasing attention has been given to incentives that encourage the use of environmental and natural resources in a sustainable manner. This growing interest is not least due to the frequently disappointing performance of command and control measures. Different kinds of incentives can be developed in isolation or in combination, including tradable use/access rights, taxes/subsidies, codes of conduct, eco-labelling and others. While practical experiences are still very limited in aquaculture, these measures have proven effective in other sectors to induce producers to adopt better and more environmentally friendly production practices.

Ichiro Nomura, Assistant Director-General, FAO Fisheries Department, notes in the forward of The State of World Fisheries and Aquaculture 2004 –

Developments during the past two years confirm the trends already observed at the end of the 1990s: capture fisheries production is stagnating, aquaculture output is expanding and there are growing concerns with regard to the livelihoods of fishers and the sustainability of commercial catches and the aquatic ecosystems from which they are extracted. The State of World Fisheries and Aquaculture 2004 reports on several of these issues.

It is not only fishers and fish farmers who have these concerns; they are increasingly shared by civil society at large. Moreover, the importance of international trade in fish and fish products, combined with the trend for major fishing and trading companies to operate on a multinational basis, means that such issues are becoming global in nature – affecting a growing number of countries, be they large fish producers or large consumers of fish. It is heartening to note that governments and other stakeholders have begun to collaborate with their neighbours and partners in trade in an effort to find shared solutions.

Concrete examples of positive outcomes of this “globalization of concerns” are the establishment of new regional fishery management organizations and the strengthening of existing ones. It is probable that ongoing discussions among intergovernmental organizations on topics such as trade in endangered aquatic species, the use of subsidies in the fishing industry, and labour standards in fisheries will also result in agreements of overall benefit to world society.

Given the nature and tone of the international discussion on fishery issues and the developments observed during recent years, I believe that fishers and fish farmers, in collaboration with governments and other stakeholders, will overcome the obstacles they face currently and will succeed in ensuring sustainable fisheries and continued supplies of food fish at least at their present levels.

Science magazine (3 November 2006: Vol. 314. no. 5800, pp. 787 – 790 DOI: 10.1126/science.1132294) reported a less bright future: (from the reprint summary)

A Need for a Sea Change
The significance of the ocean’s declining diversity on humanity has been difficult to assess. In a series of meta-analyses, Worm et al. (p. 787; see the news story by Stokstad [a summary, the balance by subscription]) quantify how the loss of marine diversity on local, regional, and global scales has affected the functioning and stability of marine ecosystems, the flow of ecosystem services, and the rise of associated risks to humanity. Similar relationships occur between biodiversity change and ecosystem services at scales ranging from small squaremeter plots to entire ocean basins; this finding implies that small-scale experiments can be used to predict large-scale ocean change. At current rates of diversity loss, this analysis indicates that there will be no more viable fish or invertebrate species available to fisheries by 2050. However, the results also show that the trends in loss of species are still reversible.

The abstract is available, the article is by subscription. New Scientist magazine carry more freely available coverage of the results of Worm’s (et al) research.

Many fisheries scientists have been sceptical of the idea that damage to a few non-fish species could be a threat to major fish stocks. But this study demonstrates, for the first time, that commercial and ecological health go together in the ocean. “Every species matters.”

In a separate article, New Scientist report that striking the balance between the need to conserve wild stocks and economic imperatives continue to challenge policy makers and the fishing industry; leading to some unhappy compromises.

Jiansan Jia and Jiaxin Chen, have published a paper (2001) entitled Sea Farming and Sea Ranching in China.

The abstract:

The various sea farming and sea ranching practices used in the People’s Republic of China are reviewed, based on published and unpublished information, statistical data and field experiences. The development of marine fisheries during the past 50 years is described. Following their decline caused by overfishing and the ecological degradation of the coastal environment, emphasis was shifted from marine capture fisheries to aquaculture-based operations, including farming and ranching of marine organisms both in inshore and offshore areas. The biology and culture of major representatives of five species groups (seaweed, molluscs, crustaceans, echinoderms and fish), involving a total of 67 different species, are presented, together with detailed production statistics. The eight sea farming and ranching systems actually used in China are presented. Several aspects related to marine resources management for sea farming and ranching are discussed, such as legislation, research on genetics and biodiversity, health management and marine habitat rehabilitation. Monitoring and evaluation according to biological, environmental and socio-economic standards are briefly considered.

The Culture and Management of Scylla Species (CAMS) project was a collaboration among four institutions worldwide – the University of Wales (Bangor) in the United Kingdom, Artemia Reference Center of the University of Ghent in Belgium, Can Tho University in Vietnam, and SEAFDEC/AQD in the Philippines. The CAMS project has reported on disease control and management projects in the Philippines and Vietnam. The objective: To improve the reliability and sustainability of crab hatchery systems through the use of probiotic bacteria as an alternative to microbials in disease control. The reports from the Philippines and from the Vietnamese research are available online. From the introduction:

For 2002 and 2003, monitoring activity of problems in large-scale hatchery rearing of crab larvae was done to identify windows of opportunity for probiotic application. These led to identification of various microbial fouling and disease-causing organisms in spawned eggs and hatchery-reared larvae.

Celia R. Lavilla-Pitogo and Leobert D. de la Pena, from the Aquaculture Department, Southeast Asian Fisheries Development Center Tigbauan, Iloilo, Philippines; published a report (December 2004) entitled Diseases in Farmed Mud Crabs Scylla spp.: Diagnosis, Prevention, and Control. From the forward:

Aquaculture production has suffered many set-backs due to the occurrence of diseases. Many of the diseases are caused by infectious organisms that are difficult to detect and need sophisticated instruments for diagnosis, but most disease occurrence and mortality in farmed aquatic animals are related to poor rearing water quality. It is, therefore, important for technicians and farmers to recognize the relationship between the animals they culture and the aquatic environment. The Government of Japan, through the Regional Fish Disease Project, funded research on diseases affecting mud crabs in order to come up with sound prevention and control methods.

This book is a collection of observations gathered from various research and commercial culture activities, and gives emphasis on disease recognition using simple techniques and gross observations of affected crabs. However, since many of the diseases are caused by microorganisms, microscopy is an important technique for their diagnosis. The authors of the book encourage active cooperation between farmers and diagnostic laboratories for disease identification, prevention, and control in order to build up more information to increase production. The Regional Fish Disease Project supports sustainable mud crab production and hopes that farmers and other users of this book will attain their production goals.

The report is located within a framed web site. Chapter 1 includes information about diseases in eggs and larvae. Chapter 2 includes information about diseases in juveniles and adults. The appendix includes documentation of various microscopy techniques. There is also a glossary.

A great deal of research into mud crab husbandry at academic levels and at more grassroot levels has been undertake in the Philippines. Esperanza A. Santos and Leah Charito T. Tambolero have written about a Bureau of Fisheries and Aquatic Resources – Fisheries Resource Management Project entitled Reviving a Coop: Rising Above Waters Through Mangrove Crab Culture. The coop also raised tilapia and prawns as secondary stocks. The authors report report: ‘After a full year implementation, the project provided substantial earnings for all the members of the coop. They hope that their learnings will be valuable lessons as well for those areas, families and people’s organizations interested to venture into mangrove crab culture.’

The Science and Development Network sumarises, and the New Agriculturalist reports on research to more closely integrate crab culture with sustainable mangrove management. From the introduction:

The rapid spread of aquaculture in recent decades has brought riches to some, ruin to many, exclusion to the poorest coastal dwellers, and environmental degradation. Scientists in the Philippines are adapting aquaculture to make it sustainable over the long term and suitable for small-scale, family-level operators. An innovative system of captive crab culture in live mangrove is being developed in the central Philippines and is now being verified and demonstrated on the southern island of Mindanao.

The Culture and Management of Scylla Species (CAMS) project was a collaboration among four institutions worldwide – the University of Wales (Bangor) in the United Kingdom, Artemia Reference Center of the University of Ghent in Belgium, Can Tho University in Vietnam, and SEAFDEC/AQD in the Philippines. The CAMS project has reported on aquasilviculture projects in the Philippines and Vietnam. The objective: To refine systems for integrated aquasilviculture of mud crabs within mangroves, specifically by reducing fish biomass requirement through low cost incomplete feeds and utilization of natural productivity. The aquasilviculture reports are available online.