By Alex Kirby
BBC News Online environment correspondent
Pressure on global fish stocks is bound to intensify as human numbers rise and wealth increases, a report says.
By 2020 79% of fish will come from developing countries (Image: Jamie Martin/World Bank)
It says the few marine wild fisheries which are not yet completely exploited will inevitably face growing pressure.
Global demand for fish has doubled in under 30 years, because of population growth in poor countries and a matching increase in demand for fish there.
And increasing environmental worries about fish production methods may hurt small producers, the report concludes.
Entitled Outlook For Fish To 2020: Meeting Global Demand, the report is the work of the International Food Policy Research Institute, based in Washington, DC, and the WorldFish Center of Penang, Malaysia.
It sets out to analyse world fisheries in terms of market forces rather than environmental pressures.
The authors say catches of wild fish have levelled off since the mid-1980s, and many fish stocks are so heavily exploited that their future is in doubt.
But world fish consumption has leapt from 45 million tonnes in 1973 to more than 91 million in 1997.
The report says: "Consumption of fish in the developed countries stagnated between 1985 and 1997, mainly because populations remained stable and people there were already eating large quantities of fish.
"But at the same time, rapid population growth in the developing world, along with increases in the average amount of fish consumed per person in those countries, led to soaring increases in global fish consumption."
The authors used a global model of supply and demand for food and feed commodities. While on present trends most foods are likely to fall in price over the next 20 years, they say, fish prices will probably rise, reflecting a global demand that outruns supply.
The model shows developing countries both producing and consuming a much greater share of the world's fish in future, and trade in fish commodities increasing.
With fish farming (aquaculture) growing explosively, concerns about effluent pollution, the escape of farmed fish, land use and pressure on wild fish to make fishmeal will also increase, unless technology and policy development promote what the report calls "sustainable intensification."
It says: "Small, poor producers are at risk of being excluded from rapidly growing export markets unless ways can be found to facilitate affordable certification of food safety and environmentally sound protection."
The report points to five major structural shifts, which it says are already under way:
- developing countries, especially in Asia, will dominate production systems
- trade between developing countries will become increasingly important with the emergence there of urban middle classes
- overfishing will remain "a huge concern", and environmental demands will strengthen
- new technology will be developed, and will probably help to reduce the amount of fish used in aquaculture
- without institutional change the fishing industry will not help to reduce poverty, and the future for small, traditional fishing communities in poor countries will remain "not bright".
The report concludes that the industry can help in fighting poverty, and in lessening its environmental impact, but that it will not be easy for it to do so.