.... 25 Years of Improvement

Part V. Aquatic Resources

With marine catches stagnating due to full exploitation and overexploitation of commercially important stocks, quickly rising demand can only be met through more rational fisheries management, resource development and aquaculture. The number of currently still underexploited major fish stocks has decreased from30 to 7 over the 1980s, and one in every three major stocks is overfished. Developing countries, whose populations will attain 80 percent of the total worl d population by 2025, will be hardest hit if world fish production declines.

The aquaculture sector, where increased production is most likely to come has made only modest gains in most countries though a few, such as China, India, Indonesia, Philippines and Thailand, have made large gains in the last 10 years. Aquaculture technology, particularly in marine resource systems, lags behind agriculture in development of technologies for farming. Technical advances inaquaculture have the potential to lead to productivity increases similar to those in food crops and livestock, provided due regard is taken of environmental limitations and negative impacts on biodiversity.

CONSTRAINTS

The major biotic constraints to aquatic resource production are:

A. The capture fisheries resources are finite and limited; they face depletion (losses from their maximum potential) through these biotic factors:

• over-exploitation by fishers
• reduction of high value species
• reduction in biodiversity from intense fishing

and through these abiotic factors:

• pollution
• habitat destruction

The economic factors which cause overexploitation include:

• too many people dependent on the resources
• high demand, especially for high value species by developed countries

B. The aquaculture (fish farming) sector has the following biotic constraints:

• poor development of aquatic genetic resources
• lack of attention to local species as resources

and these abiotic constraints:

• limited land, water and infrastructure for uptake in many coastal and inland sites
• some present systems may be environmentally unsustainable
• diseases and parasites

The economic factors constraining aquaculture include:

• lack of capital availability
• frequent lack of economic sustainability
• difficulties in technology transfer to new entrants

ACTIVITIES

A. CAPTURE FISHERIES

Biotic constraints:

Overexploitation has been addressed through:

• very successful methodologies to assess status of tropical aquatic resources, allowing researchers to advise managers of management needs on a rational basis
• improved ways of managing the resources through, for example, joint government-community management
• improving access to necessary information and tools among NARS through collaborative research, information networks and global data bases

Reduction in biodiversity has been addressed through:

• documenting and assessing the status of fisheries resources and coral reefs for the first time on a global basis.

Abiotic constraints:

No impact yet, but ICLARM is developing tools to predict and manage the interaction of land- and water-based activities, such as agriculture and fisheries, respectively, to minimize pollution and habitat destruction.

B. AQUACULTURE OR FISH FARMING

Biotic constraints:

• Poor development of genetic resources has been addressed through development of a new strain of a fish of a common species of tilapia (Nile tilapia) which is used in some 60 countries. The new strain, dubbed super tilapia, shows greatly improved growth and survival in farmers' ponds. This success has led to an international network to develop national fish breeding programs for tilapia and carp (International Network for Genetics in Aquaculture -- INGA).
• The use of new local species has been demonstrated in ICLARM's pioneering technology for rearing giant clams in the Pacific and inland native fish in Africa. Giant clam hatcheries are now appearing around the Pacific, while the potential of native fish has helped one African country to date (Malawi) in its aquaculture development policy. This African work is being extended to other countries of the Southern African Development Community.

On the abiotic constraints to aquaculture:

• Land limitations are addressed in research in several countries including Bangladesh through which farmers are integrating small-scale ponds into farms and rice floodwaters; landless persons including a high percentage of women now have technology t o use roadside ditches and other seasonal water bodies.
• Unsustainable systems are also being replaced through the integration of aquaculture into degraded farming systems. Impact at the pilot level has been ver y high in Bangladesh, Ghana and the Philippines.

On economic constraints to aquaculture:

• Many aquaculture enterprises are capital and knowledge-intensive. Knowledge constraints are being addressed by researchers working with government and non-government extension officers and by involvement of the farmers themselves inparticipatory research so that the systems designed are more likely to be useable by the farmers. The lack of capital and economic sustainability has been overcome to some extent through promotion of low-input integrated systems.