FAO Home>Fisheries & Aquaculture
Food and Agriculture Organization of the United Nationsfor a world without hunger
The introduction of Chorkor ovens has drastically improved fish
The introduction of Chorkor ovens has drastically improved fish
curing methods in West Africa, reducing waste - FAO/16533/P.Cenini


The generally acknowledged limits of production from capture fisheries, coupled with the widening gap between the supply and demand of fish for human consumption, reaffirms that post-harvest losses are an unacceptable waste of scarce natural resources. Post-harvest losses of fish occur in various forms. The physical loss of material are caused by, for example, poor handling and preservation or the discarding of bycatch. Economic losses occur when spoilage of wet fish results in a value-decrease or when there is a need to reprocess cured fish, raising the cost of the finished product. In addition, inadequate handling and processing methods can reduce nutrients, leading to nutritional loss. Similarly, the lowering of large quantities of fish catches into animal feeds can be considered under certain conditions as a "loss" for human food security.

Post-harvest losses in small-scale fisheries can be among the highest for all the commodities in the entire food production system. Fish losses caused by spoilage are estimated at 10 to 12 million tonnes per year, accounting for around 10 percent of the total production from capture fisheries and aquaculture. Appropriate preservation methods can significantly reduce this loss, including from glut catches when the processing, distribution and marketing system cannot cope with the exceptional quantities of fish that are sometimes landed due to seasonal or inter-annual variations of availability or abundance.

Physical loss also results from the discarding of bycatch. This type of loss is especially significant in shrimp trawl fisheries where the proportion of co-occuring species caught incidentally is very high and can reach 95% of the total material taken on board. Bycatch contains a variety of fish sizes and species and is often thrown back at sea, except in densely populated areas of many developing countries where it is largely used for local consumption. Some, particularly larger fish, could be landed and sold on the main market, but even those fish are of much lower value than the shrimp. Chilled or frozen storage facilities on board the trawlers are limited and are mostly kept for the main target species. Sorting the bycatch would require additional crew time further reducing the financial incentive. It is currently estimated that around 20 million tonnes of fish catch are wasted in this way.

A particularly sensitive issue is the discard resulting from finning of sharks where the discarding of the whole animal at sea is considered both wasteful and unethical. Some quota policies or legislations prohibiting landing of small sizes tend to encourage discarding practices. The actual level of discarding observed in many fisheries would rarely be optimal from a societal perspective. In some cases the problem is aggravated by management policies. In other cases, the costs arising from discarding are not borne by the "discarders" but may be shared by other groups in society including other fishers in the same or overlapping fisheries, fish consumers and others in society who may experience some disutility as a result of discarding some species

About 25 percent of the total inland and marine catch is still processed into fishmeal and fish oil, using mainly small pelagic oily fish such as herrings, sardines, mackerel, anchovies, pilchards, sand eel, and menhaden as well as offal from other more valuable species (e.g. tuna). Recycling fish catches as feeds for poultry or pigs results in a net loss because there is a need for 3 kg of edible fish to produce approximately 1 kg of edible chicken or pork. In the most efficient aquaculture systems, 5 kg of edible fish are needed to produce 1 kg of cultured carnivorous fish. Therefore, while fishmeal and oil are the result of acceptable and efficient fishing strategies, they are often considered a "loss" from a food security perspective. Ideally, reduction into fishmeal and oil should only occur when it is not economical or practical to utilize fish for direct human consumption. This may happen, for instance, when preservation technology is not available, the distribution chain is inadequate or food habits do not encourage human fish consumption.


Reducing post-harvest losses requires wiser use of resources, reducing spoilage and discards and converting low-value resources, which are available on a sustainable basis, into products for direct human consumption. Reducing spoilage requires improved fish handling on board, processing, preservation, and transportation, all of which are particularly deficient in small-scale fisheries.

Proper preservation methods eliminate waste
Proper preservation methods eliminate waste
FAO/FIIU Photo Library/Peter Benembarek

With increasing fish scarcity, the problem of discards tends to resolve itself at least partially as new species previously deemed commercially inferior are progressively integrated into consumer feeding habits and markets. This is insufficient, however, and efforts are needed to use more appropriate technologies systematically, such as square mesh, bycatch excluder devices, turtle-excluder devices, bird and cetacean scaring devices in longline and driftnet fisheries respectively.

Progress is also required in processing low-value fish for human consumption. Various types of discard bans are being implemented: total, selective (species-related) or partial (area-related). Experience shows that discard bans may be effective where control of shore-based infrastructure is easy, facilitating compliance, and where other measures have already reduced discarding to a minimum. Furthermore, they are not effective where discard rates are inherently high, fisheries are geographically dispersed, proportion of juveniles in the stock is high or where there is a lack of a compliance culture.

Flexible closed areas in which threshold conditions for ad hoc closure are related to discard rate and/or composition are increasingly used as real-time reporting vessel monitoring is improved (e.g. through satellite communication). Partially closed areas may also be accessed to vessels meeting certain conditions (e.g. using bycatch excluder devices). In both cases, the trend towards greater decentralization of fisheries management responsibilities may be a positive factor.

Discards can also be reduced with the operational flexibility given to fishers in multi-annual or multi-species quota policies. More flexible quota and size-at-landing policies are also needed to lower discarding and high-grading (e.g. allowing a small percentage of undersized landings). In some cases only barring the gear itself could reduce the problem, though the cost would be prohibitive.

Low-value species such as small pelagic or mesopelagic species could, in theory, be used for human consumption if problems of acceptability, transformation and distribution could be resolved. Large quantities of meal are often produced in upwelling countries with arid and scarcely populated coastal areas (Peru, Chile, Namibia) or countries where the consumers prefer meat (Latin America, Mauritania, USA) or have easy access to higher quality imported fish (Europe and USA).


Numerous actions to reduce waste already exist, some of which are highlighted below. The need to decrease all forms of waste and to optimize the use of fisheries resources for human food security is embedded in the FAO Code of Conduct for Responsible Fisheries, as well as in the UN Fish Stock Agreement.

Reducing spoilage: For many years, FAO has implemented a wide range of activities, including training fish technologists in developing countries, to introduce appropriate technologies for lowering fish spoilage, especially for small-scale fisheries. Using insulated fish containers and training people on their design and construction has enabled many countries to increase fishing trip duration, while keeping fish iced for a longer period of time. For instance, nowadays, many West African countries send by air to Europe fresh fish caught using pirogues equipped with insulated containers. Likewise, many countries have extended the concept of insulated containers to the distribution system. Some use local insulating materials such as coconut fibre, sawdust or rice husks for building containers transported on bicycles or mules. FAO programmes have also aimed to improve handling practices, especially in small-scale fish landing sites, and fish preservation methods such as smoking, drying and salting. In this respect, FAO was able to adapt and ameliorate drastically the traditional fish curing methods used in many developing countries. For instance, a traditional fish smoking oven from Ghana, called the Chorkor, was adapted and re-designed to improve fuel efficiency, working conditions of the women who smoke fish and the quality of the finished product. The Chorkor oven is now widely used in many other Africans countries. Over the last 10 years, many NGOs have taken an active role in disseminating these appropriate technologies in developing countries.

Such post
Such post
harvest losses could be avoided with appropriate measures - FAO/FIIU Photo Library


Information on bycatch and discards is being collected more systematically by observers. Most shrimp trawl fisheries (e.g. in Central America, India, Thailand) are now landing more bycatch for human consumption than in the past, partly due to increasing demand and prices paid for fish. As well, many countries have introduced turtle excluder devices to lower bycatch. Efforts are also being made to enhance the utilization of bycatch. FAO has organized a number of technical meetings to promote sustainable fishing technologies and reduction of discarding practices. An International Plan of Action for Reducing Incidental Catch of Seabirds in Longline Fisheries was adopted in 1998. The question of improved shark management is addressed in the 1998 FAO International Plan of Action for the Conservation and Management of Sharks. Regional fishery bodies (e.g. CCSBT, CCAMLR) have implemented measures to mitigate seabird bycatch during longline fishing operations. The regulatory measures on bycatch and discards, as well as those on incidental catches, are strongly engraved in NAFO's Conservation and Enforcement Measures. Some countries, including Peru and Chile, have begun work in the industrial anchovetta fishery aiming to eliminate the practice of discarding. The 1992 La Jolla Agreement resulted in an annual reduction of dolphin mortality from some 16 000 in 1992 to about 3 000 currently. Since 1998 the countries involved agreed on even stricter provisions for dolphin protection, consistent with the relevant terms contained in the Code of Conduct for Responsible Fisheries and the UN Fish Stocks Agreement.

Developing products for human consumption from low-value resources: In many Latin American and Northwest African countries, with abundant low value fish resources, several attempts have been made to increase the use of these resources for human consumption. The introduction of chilled or refrigerated sea water (CSW, RSW) technologies for on-board fish cooling has been successful in some countries. Despite its great promise in the 1960s, the production of fish protein concentrate (FPC) was abandoned many years ago and efforts were shifted to develop new products acceptable for human consumption. Although the technologies for many of these, such as the production of surimi from sardines, has been developed, their acceptability for local consumption or their introduction on the international market has not often been given sufficient consideration. Local food habits for local markets and sanitary requirements and marketing strategies for international trade are essential components that require adequate priority in product development. However, there is a change towards successful relocation of labour-intensive product value addition to developing countries. This is well illustrated by the salted anchovy industry that has seen a major growth these last 15 years in North Africa and Latin America.

The combination of market signals (the gap between supply and demand) and environmental pressures (including ecolabelling schemes) are particularly favourable for bettering the current situation. There have been several successful improvements of fishing gear and practices in the past 10 years that have reduced the catch of juvenile fish and non-target species. Much of this progress, however, has occurred in developed countries and the transfer of appropriate technology to less developed countries is still needed. The growing awareness and involvement of the industry is a factor of success for the implementation of sustainable fishing technologies and practices. In addition, increasing fish quality requirements in the main import markets and the related spread of HACCP technique implementation also represent a significant incentive for amelioration. The situation regarding post-harvest losses should therefore improve noticeably during the next decade.

Powered by FIGIS