PRIMARY PRODUCTION
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Investigation of possible outlets for the end products, both solid and liquid, of the various treatment processes under trial continued. This resulted in the preparation of a scheme for the pelleting of dried manures along with other feedstuff constituents -- the pellets to be fed initially to pond fish.
Fishing Industry
Marine fish form one of Hong Kong's most important primary products. More than 150 fish species of commercial importance frequent the waters of the adjacent con- tinental shelf. Most important of these in terms of landed weight are golden thread, scads, lizardfish, big-eyes, sardines, conger-pike eels and croakers.
Total estimated production from the two major sectors – marine capture and culture fisheries - amounted to 162,500 tonnes with a wholesale value of $833 million in 1978. These figures represent increases of 2.7 per cent in weight and 13.6 per cent in value compared with the previous year. Of the total production, 96 per cent in weight came from marine capture and four per cent from culture fisheries. In terms of wholesale value, 89 per cent came from marine capture and 11 per cent from culture fisheries. An estimated 35,700 fishermen work a fleet of 5,500 vessels, of which 93 per cent are mechanised. There are four major types of fishing in terms of gear: trawling, lining, gill-netting and purse-seining. Trawling is the most important, accounting for 67
per cent or 73,400 tonnes of marine fish landed in 1978. The total landed catch of live and fresh marine fish available for local consumption in 1978 amounted to 87,731 tonnes with a wholesale value of $386 million. This represented 91 per cent of the local consumer demand.
Pond fish farming is the most important culture activity. Fish ponds totalling 1,975 hectares are located in the New Territories, principally in the Yuen Long district.
Traditional pond fish farming is similar to that practised in China for hundreds of years. Several different carp species are cultured in the same pond, each deriving its food from a different source and thus utilising to the utmost the nutrients introduced. Grey mullet is often cultured with carp, but the natural production of its fry, caught in the sea, was inadequate during the year. Ponds are generally rain-fed and pond fish farmers experienced the alternate effects of drought conditions in 1977 and heavy rains in 1978. More intensive forms of culture using snakehead and catfish, whose annual yield can be 10 times that of the carp-mullet culture, are gaining prominence. Despite the increasing urbanisation of the New Territories, the land area devoted to fish ponds has increased and they yielded 5,790 tonnes in 1978 or 16 per cent of the local consumption of freshwater fish.
The 1970s have witnessed the rapid development of marine fish culture, whereby young fish are captured from their natural environment and fattened in cages sus- pended from rafts in sheltered bays throughout Hong Kong, particularly in the eastern New Territories.
In late 1977, one of the largest of these centres was severely affected by an oil spillage from a grounded freighter on Lamma Island. The recent scarcity of young fish for rearing also has restricted the growth rate of the industry. Nevertheless in 1978, the total of live marine fish supplied by this activity from some 40 sites was 680 tonnes valued at $27.8 million.