Shortage of ocean fish rocks the 'cradle of aquaculture' into action
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At present, collection of young from the wild incurs high costs -- over 1 billion milkfish fry were trapped last year in Philippines waters, involving many nurseries and middlemen and a high dependency on mother nature.Skip to next paragraph
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In developed nations, poultry farming did not "fly" until good genetic stock as well as better feed came out of the lab. Aquaculture awaits the same level of husbandry -- growing fish like cattle or chickens in feedlots, stuffing them to the gills until they're ready for market. Israel, perhaps the most advanced nation in aquaculture, has learned to provide automatic feed and oxygen into high-yielding fish ponds.
Like the popular slogan "appropriate technology," used by development experts , fish biologists are beginning to look for the "appropriate species" that would fit well into local social and economic conditions. Milkfish, for instance, can often rely on pond bacteria for food rather than high-cost feed that other species might need. Shrimp breeders, for instance, recently discovered that a young shrimp with one eye purposely broke will, strangely, reproduce in captivity. At present, shrimp farming still relies on ocean capture of fry.
The Philippines has plans to end fish imports and become self-sufficient through greater milkfish farming. Outside Manila, the freshwater lake of Laguna de Bay is home to some of the highest milkfish yields yet. In Malaysia, aquaculture now accounts for 80 percent of government spending on fisheries. Even landlocked, mountainous Nepal last year received a $11.8 million loan from the asian Development Bank to nurture a budding aquaculture industry for the food-poor country.
Rather than just expand present methods, however, work is under way to exercise greater control over the stocks with more intensive farming. Use of cages and pens, rather than open ponds, helps cut demand for land. Special emphasis is being given to air-breathing species, specifically catfish, which would require less water flow and allow denser populations.
At India's Central Island Fisheries Research Institute, researchers are developing catfish for cage-growing in unused swamps, where oxygen levels are low. And some scientists believe that deep ocean currents full of rich nutrients can be diverted into coastal "sea ranches."
One challenging potential will be a combination fish-rice-animal farming, in which cross-fertilization benefits the whole farmlot.
At present, less than 1 percent of Southeast Asia's irrigated rice fields are used for culturing fish. In Thailand's Pongsuwana region, the fish culture brings more income than the rice. Such differences cause tenant farmers in Java to cede their entire rice crop over the landowners in exchange for the right to culture fish in the fields. Thus, any fish-rice farming could have serious implications for land ownership in Asia.
In Malaysia, experiments with raising ducks overm fish ponds shortened the culture period of fish by two months with the fertilizing effect of the bird droppings. Similar results were reported in Taiwan when pigs are grown near Chinese carp farms. In Philippines, such simultaneous farming methods are known as palay-isdan, dating back to antiquity.
But increasing pesticide and fertilizer use on new rice varieties, plus parasites in animal manure, have been shown to damage fish, posing high hudrles for scientists to overcome.
Although more biological breakthroughs are needed, especially in breeding techniques, perhaps the longer-range problems are social and economic. The aquaculture field today is dominated by biologists who, says Dr. Shehadeh, have to be tempered by economists.
For instance, investors in the Philippines are buying up fish farms that yield four tons of milkfish per hectare (about 2 1/2 acres). But local farmers say they can get more profit if they skip the high cost of feed and fertilizer, settling for two tons a hectare.
The international aquatic center, funded largely by the Ford Foundation and US aid, finds aquaculture's weakest link is a lack of skilled people. "There are more projects than people to run them," says Dr. Shehadeh. The center maintains eight full-time professional and many part-time consultants on a meager budget of $1.8 million this year. SEAFDEC has begun training several dozen "Asian aquaculturists." And the World Bank is spending $38 million for a Philippine fishery training system.
Still, most aquaculture is still traditional -- father-to-son knowledge -- while the more profitable operations tend not to reveal their secrets.