Actually, they are fishing for what they can hardly see, milkfish fingerlings.
The fishermen and women work steadily back and forth in water at chest height, pushing a pair of bamboo booms. In suspension between them, a fine funnel of mosquito net guides the fingerlings down into a plastic collecting trap.
On the beach after half an hour's sweep, the harvested fingerlings are released from the trap into a basket-shielded earthenware pot, then transferred from this to a large holding container. The fingerlings, so transparent and tiny as to be near invisible, show up against the basketed pot's white interior glaze only to the experienced, or very keen eyed, each fingerling just two minute eyes like a ":" on a white page.
Each sweep yields only a dozen or so of these fry, a miniscule contribution to the millions required each year for the more than 15,000 hectares of milkfish ponds in Taiwan.
On other beaches, in coves and estuaries, the coastal people gather from April to June to make their harvest, a catch greatly increased by booms operated off the motorized plastic rafts common in Taiwan's coastal waters; these sweep the seas up to a kilometer off the coast. Most of the fry are channeled through fry dealers for distribution to fish farms concentrated along the shores of Taiwan's Yunlin, Chiayi, Tainan, Kaohsiung, and Pingtung areas.
Essential to the milkfish is a steady growth of the algae on which it feeds. It is a semi-tropical fish, so sensitive to cold it will not tolerate water temperatures below 15°C.
The mature milkfish is a fine table fish. The immature catch is used as bait by longline fishermen.
Until six years ago, milkfish were, far and away, the main product of Taiwan's aquaculture network, a fisheries system is in which Taiwan outdistances other producers in both overall efficiency and intensity of cultivation.
Milkfish were also the original basis of Taiwan's aquaculture industry, their controlled culture dating back over three centuries; the technique was developed first on the mainland, then brought to the island's Anping area, near Tainan. Dikes were built along the shores to make culture ponds, which were then stocked with fry caught in coastal waters. The success of such ponds in recent times has encouraged active private investment, followed up by government support through research and marketing facilities.
Milkfish long enjoyed an easy market, with undersupply in bad seasons the main problem facing suppliers. However, in more recent years, the introduction of tilapia, a semi-tropical fish, has challenged the milkfish. Various types of tilapia have been introduced from Indonesia, Japan, Israel, and South Africa, the most successful being lines of the T. Mossambicus, for taste and formation often compared to the prized sea bream. For the fish farmer, probably its greatest attributes are its fast growth rate and easy adaptation to artificial propagation, which enable three crops per year under favorable conditions.
Tilapia are all generally known in Taiwan markets as Wu-kuo fish, after the two researchers who introduced the breed. However, more commonly raised now is the new Fu-shou (Blessed fish), a cross derived from T. Mossambicus and the Nile tilapia, O. Niloticus, capable of a daily growth rate of 1.16 grams—nearly double that of the parent breeding stock.
In order to maintain such a high growth rate, pool populations have to be carefully controlled, a difficult operation with a fish so prolific in its reproduction. The traditional method, hand-sorting fingerlings to select all-male pool stock, in the past few years has been replaced by two types of genetic manipulation—controlled breeding for all-male fry production and sex inversion with steroid treatment. These techniques, developed by the Taiwan Fisheries Research Institute, have since been extended to farmers and hatcheries.
A unique development in Taiwan is the appearance and stabilization of a "red tilapia" strain, believed to have originated as an albino of the mossambicus line; its reproduction has been achieved through a cross between the albino and O. Niloticus, with subsequent selection leading to nearly 90 percent red fry. Very popular in Japan, a large percentage of the red tilapia harvest is exported live for that country's restaurant trade.
RED tilapia rearing can be observed on Taiwan in the idyllic surroundings of the Tsengwen Reservoir, where Cheng Wen and three other fish-farmers have established floating farms—their fish are corralled in nets suspend ed from pontoons secured in a grid.
Chen, a slightly built, active man, sat us down when we visited his floating home-and-farm, and immediately insisted that we sample his product. He rushed to net the largest available, then proved to be as fine a cook as a fish gardener, whipping up a delicious dish.
While tilapia is the major product of island aquaculture, the star performer in terms of fast development over the past five years is the grass shrimp. Known by this name for its habit of hiding in estuary grasses, the succulent crustacean was previously raised only as a fringe benefit of milkfish rearing. The shrimp fry were more or less accidentally caught with the milkfish fry and handled together, or for semi-intensive shrimp culture, the fry were specifically collected in grass traps and used to stock ponds.
The big breakthrough came six years ago when the grass prawn, Panaeus monodon, was successfully artificially propagated. From then, production has soared to over 50,000 tons per year, stimulated by a strong export market for live prawns. Taiwan now ranks as the world's second largest producer of prawns from aquaculture, with various varieties being raised to fit the demands of different markets.
There are now over 400 prawn farmers in Taiwan, a good concentration of them highly visible along the coast near Hengchung in Pingtung. There, acres and acres of flat coastal area are divided into large ponds, the characteristic feature being floating paddle wheels which serve as aerators. The prawn hatcheries themselves are now a well developed business, supplying a half million fry for every hectare of pond, about 75 percent of which will mature for market.
A new facet is the export of live prawns, utilizing a recently developed packing technique—the prawns are placed dry among polystyrene beads and chilled for shipment. Packed like this, they can survive thirty hours before they have to be put back in water.
Despite this rosy picture, the overall going is not all duck soup, as it were, for the prawn farmer. Prawns are bottom feeders, susceptible to acute disease problems, a difficulty both at the hatchery and rearing pond. Reportedly, at least 20 percent of the prawn farmers do not see a profit for each crop season. But to offset this, there is the fact that up to three seasonal crops can be harvested each year depending on the type of prawn raised.
The grass prawn is favored for a fast growth rate on low-protein, low-cost feed. While it is the staple of the volume industry, exotic varieties with more finicky feeding habits are also being raised—for luxury markets willing to pay up to US$12.50 per kilogram.
IT is an anachronism that fisheries are generally considered a fledgling, less developed science-and-agricultural industry—in China, at least, where fish culture has traditionally been better appreciated than elsewhere.
The old Chinese saying goes, "Give a man a fish and provide one day's food; teach him to raise fish and provide a lifetime's food." And inscriptions on ancient oracle bones offer even more direct evidence of the importance of fish culture to early China. One clear historical description of a method for raising carp, by Fan Lee in the 5th Century, B.C., is contained in an account of a discussion with the King of Wei, in which Fan Lee was accounting to the King the reason for his great wealth—all from carp raising. The account shows a considerable understanding of the life cycle of the carp and of means for its propagation in pond conditions.
Carp still retain an important position in the aquaculture industry in Taiwan, one reason being the preferences of different types of fish for feeding in different ecological niches—a special suitability for polyculture (rearing in pools with other fish).
In Taiwan, apart from the normal market, carp are favored in the sport fishing provided at private recreation ponds around the cities. And though carp have been gradually displaced from the daily table by tilapia, they currently still hold their own in terms of production by weight and value for many reasons. Regardless of the influence of whatever new breeds on the future market, carp will likely keep a special place in the hearts of the Chinese people. After all is said and done, it is usually a giant carp that has the central place on the Chinese New Year's table, symbolizing bounty in the coming year. And the picturesque fish is depicted in countless Chinese paintings.
Top dog—er, fish—in cultivation in Taiwan is, however, the eel. It commands high prices due to strong exports to Japan, which consumes over 80 percent of the 30,000 tons produced on the island each year. Eels have an interesting and not completely understood life cycle, and have defied efforts of researchers at artificial propagation, but not at cultivation. The preferred eel in Taiwan and Japan is Anguilla japonica, which matures and spawns in the seas southwest of Taiwan. The next generation then returns to the coast as glass eels, or fry, transparent fingerlings about 6 cm. in length. These naturally migrate up rivers for another three to four years of their life cycle before returning to the seas to mature and spawn a new generation.
The local glass eel catch, when inadequate, is supplemented by European imports. Taiwan is climatically well suited to cultivating them, as eels require warm waters, stopping feeding, and therefore growth, in cold waters. Centers for eel farming in Taiwan are Changhua and Pingtung, though a limited amount of eel farming is also done in Ilan in the north, where waters are warmed by the geothermal currents of artesian wells.
Still another important aquacultural effort in island coastal waters is the raising of oysters, whose production value exceeds those of tilapia and milkfish. An aqua-enterprise with a long history, oyster culture faces serious threats from modern water pollution, as indeed do all global fish-raising industries. In order to contend with Taiwan area problems, "off-the-bottom" cultivation is being developed, a move up from the traditional practice of anchoring them to bamboo sticks planted in shallow, sandy seabeds.
Off-the-bottom culture includes growing the oysters on lines hanging from pontoons or on long lines stretched between pontoons or buoys secured to the sea bed. Both techniques allow cultivation in deeper waters, and thus protection from sources of pollution by means of dilution and the relocation upward, away from bottom sediment.
The oyster is a very popular seafood in Taiwan as evidenced by a proliferation of Taipei restaurants and sidewalk street stalls featuring oyster dishes. Also popular, in soups or fried (and very salty), are clams, also commonly cultivated.
Cultivation of a seaweed, Gracilana confervoides, has received recent stimulus from the development of new packaging and marketing techniques. Parents trying to avoid dental caries can now substitute seaweed, dried and attractively packaged, as snack treats for their children.
Accompanying the continuing advances in understanding of aquatic life cycles are growing opportunities for commercial polyculture—mixed-fish farming—and for integrated livestock-crop-and-fish farming. Such polyculture systems often mix carp of different types or carp with other fish species; another example is the semi-intensive rearing of prawns with milkfish in one management operation.
Integrated systems are now receiving a lot of attention as they provide not only the opportunity for utilizing farm waste products, but also for the control of pollution from hog and poultry farms. Flow diagrams of integrated production procedures become complex: Grain crops feed chickens whose droppings go to the pigs whose manure goes to the fish pond whose bottom muck goes back to the grain fields as organic fertilizer. But this is only a basic flow line; there are many detours and feedbacks as a result of the use of other byproducts, like rice husks, ash, and biogas.
That the same sound, yu, should serve as the Chinese word for both "fish" and "plenty" is appropriate not only for traditional symbolism, but for the contemporary state of the fish raising industry in Taiwan. As in other sectors of island production, the problem now is connected with abundance, and the most immediate pressures have to do with marketing. One successful approach involves thoughtful diversification, utilizing higher technologies to specialize in production of higher-value fish, like the red tilapia. The challenges to aquaculturalists do not in any way seem less, now they have achieved their major goal of adequately supplying the basic market need.