The Sustainable Intensification of Aquaculture

Two new reports out this week urge greater integration of fish in achieving food and nutrition security and sustainable food systems.

The World Resources Institute in their fifth instalment of the soon to be released World Resources Report, partnered with WorldFish, the World Bank, INRA, and Kasetsart University to explore how aquaculture can grow sustainably, reducing its environmental impact and contributing to food and nutrition security.

Aquaculture is a rapidly growing industry and production between 2000 and 2012 more than doubled. Aquaculture output is growing at 6.6%  per cent per annum worldwide. As wild catch fish stocks decline, peaking in the 1990s, aquaculture becomes ever more important for meeting demands for fish, which contribute one sixth of animal protein consumed across the globe. To meet future demand it’s estimated that aquaculture production will have to increase by over 100% by 2050.

Aquaculture has been linked with some serious environmental concerns particularly for high-input high-output intensive systems – the eutrophication of lakes and transformation of species assemblages on the seabed as a result of nutrient enrichment; the physical degradation and clearing of coastal habitats such as mangroves for shrimp aquaculture; the introduction of non-native species to natural ecosystems; and the salinisation of drinking water resources, for example. Already large-scale improvements to the aquaculture sector are taking place: increasing resource-use efficiency, mangrove conversion is largely being prevented and the share of fishmeal and fish oil in feeds is declining, putting less pressure on wild fish resources.

Without appropriate management of these systems, however, the intensification of aquaculture, as wild fish stocks decline and demand for fish increases, could also intensify these environmental impacts. Sustainable intensification is called for, in the case of aquaculture defined as: advancing socio-economic development; providing safe, nutritious food; increasing the production of fish relative to the amount of land, water, feed, and energy used; and minimising water pollution, fish diseases, and escapes. The WRI paper explores various scenarios of aquaculture growth to 2050 to investigate whether the sector’s development can be sustainable. They find that under most scenarios environmental impacts, such as greenhouse gas emissions, are increased. The report recommends five approaches to transforming the aquaculture sector, increasing production while reducing its impacts:

Investing in technological innovation and transfer such as improvements in breeding technology, disease control, feeds and nutrition, and low-impact production systems, areas relatively unstudied in aquaculture, a young sector compared to agriculture.

Focusing beyond the farm by using spatial planning and zoning to avoid large concentrations of producers and maintaining numbers of producers the surrounding ecosystem can cope with.

Shifting incentives to reward sustainability, for example providing training, technology and water supply in exchange for operating in government-delineated aquaculture zones.

Utilising the latest information technology such as remote sensing, open access data and ecological modelling to improve spatial planning and monitoring as well as increase transparency and accountability.

Eating fish that are low on the food chain, species that don’t require large amounts of wild fish in their diets such as tilapia, catfish, carp, and bivalve molluscs.

A second new report produced by the High Level Panel of Experts (HLPE) on Food Security and Nutrition of the Committee on World Food Security, Sustainable Fisheries and Aquaculture for Food Security and Nutrition, is a review and synthesis on current knowledge on the contribution of fish to global food security. Fish play an important role in diets worldwide, particularly in coastal and island countries where they can make up 50 to 60% of all protein consumed, and the report recommends that fish, which often receive little attention in policy, need to be fully integrated into all aspects of food security and nutrition policies and programmes.

The report details the threats to fisheries and aquaculture from pollution and overexploitation to coastal infrastructural development and climate change. Aquaculture not only represents an opportunity to reduce pressure on wild fish stocks but an alternative to livestock systems which, in many cases, have higher greenhouse gas emissions and lower feed conversion ratios.

While it is estimated that more than 120 million people in the world depend directly on fisheries-related activities (fishing, processing, trading), the majority living in developing and emergent countries, the links between aquaculture and food security are unclear, made harder to discern by the large-scale international trade in fish. In Africa, small-scale, subsistence aquaculture has not led directly to a reduction in poverty and food insecurity, and focus is now moving towards medium-scale, more commercial-oriented enterprises.

The report makes several recommendations to boost the role fisheries and aquaculture can play in tackling food insecurity including conducting research such as household surveys to understand the role of fisheries and aquaculture on nutrition and hunger and mainstreaming climate change policies into all fisheries and aquaculture policies. For aquaculture specifically, national and international organisations, governments and private and public stakeholders should:

Initiate research on health control and food safety, improved feed stocks that do not directly compete with human foods, domestication and genetic improvement of key traits contributing to the various dimensions of food security and nutrition, integration of aquaculture in agroecological models of production at the farm and landscape levels, and improved linkages with food chain.They should put in place appropriate actions to reduce further the use of fish meal and fish oil as feed in aquaculture and livestock production, and promote the use of alternate sources as well as the production and consumption of low trophic level fish species. Greater South-South collaboration to encourage sharing and learning experience in aquaculture is also called for, and in particular developing an enabling environment to support this.

Aquaculture is a growing but relatively new sector. While threats to its future ability to produce enough fish are mounting, the opportunities for sustainable intensification and development are also numerous.