MANUAL OF RUNNING WATER FISH CULTURE 1. EUCHEUMA SPP.

Eucheuma, a red alga, endemic to Philippine marine waters, is the twentieth-centure wonder plant. It is so called because of its many important uses in various industries. From this seaweed is extracted carrageenan, a valuable sustance used in products that need gelling, suspending, thickening, emulsifying and water-holding properties.

Eucheuma thrives in some selected areas in tropical zones. In Asia, the major-producing countries are the Philippines and Indonesia with perhaps a little contribution from Singapore, Japan and Malaysia. Outside Asia, the biggest producer of a similar type of seaweed called Irish Moss is Canada. There had been noticeable decrease in the volume of outputs in those countries due to the indiscriminate harvesting of seaweed by lots of commercial investors.

In the Philippines, the Mindanao-Sulu area is claimed to have the richest source of Eucheuma. Based on the survey of the Bureau of Fisheries and Aquatic Resources on the known Eucheuma resources of the country, the Mindanao-Sulu area occupies 42 percent of the total suitable areas. Visayas takes a share of 28.63 percent, while Palawan is estimated 13.6 percent. Luzon area has 14.68 percent (Reyes, 1977).

Eucheuma in dried form is basically an export product of the Philippines. Most of the country's seaweeds are transported to the United States, while some find their way to Europe and Japan (Reyes, 1977).

In 1966, it was one of the important marine export commodities of the country, totalling 800 tons worth millions of pesos most of which were harvested from the wild. But the export in the five succeeding years decreased, so that its culture was started in 1975 (Borja, 1978).

A survey of the Genus, indicates that there are approximately 48 species described in the literature (Dawes, 1974). Six of these species represent Philippine Eucheuma (Trono, 1974). They are Eucheuma serra, E. arnoldii, E. procrusteanum, E. cottonii, E. spinosum and E. striatum (Figure 1).

Of these six species, Eucheuma spinosum and E. striatum, locally known as “tambalang”, are best suited for commercial cultivation, however, the latter is preferred due to its wider range of tolerance to ecological changes and is easier to farm (Trono, 1977).