The milkfish Chanos chanos (fig. 21.6), the only species of the family Chanidae, has a wide distribution, though not to the same extent as the grey mullet. It does not form a capture fishery of any significance and its importance is based on the large-scale farming in over 400000ha of coastal impoundments in Southeast Asia. Its culture is believed to have originated in Indonesia, during the 15th century, and then spread to the Philippines and Taiwan. According to available information, there are over 183000ha of milkfish ponds in Indonesia, about 176000ha in the Philippines and about 15600ha in Taiwan.The average production per ha in Taiwan is reported to be about 2 tons, in the Philippines 600kg and in Indonesia about 300kg. Many individual farms obtain much higher production in all three countries. Some small-scale culture is attempted in peninsular India and Sri Lanka, but the total production is very small.
Though essentially marine fish of the Indian and Pacific oceans, the young ones spend their life in inshore estuarine areas and ascend rivers to the fresh-water zones. They are known to be highly euryhaline, and can live in fresh to hypersaline waters. They can tolerate low oxygen levels. Temperature tolerance limits are said to range from 15 to 40°C, but the optimum temperature is between 20 and 33°C. They become sluggish below 20°C and mortality occurs at 12°C.
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