Netcage culture is a popular method of rearing finfish along the coastline. This new technology utilizes little physical facilities, less space, low initial (ban đầu) investment and is moderately inexpensive to operate. Another advantage is the easy and fast harvesting of live fish which fetch higher price in the market.There are two general types of cages, floating and stationary (adj: steisnơri: cố định). A floating cage is made up of a floating unit from which a single or a series of netcages are suspended. Some of them are mobile and can be easily towed away. A stationary cage, on the other hand, is tied to fixed poles at their corners. In Asia, finfish like grouper (Epinephelus tauvina), seabass (Lates calcarifer), snapper (Lutjanus spp.) and siganid (Siganus spp.) are cultured in commercial scales in tropical countries such as Singapore, Thailand, Malaysia, Philippines, Indonesia and Hong Kong. While other finfish like red sea-bream (Pagrosomus major), black sea-bream (Sparus microcephalus), yellow tail (Seriola quinqueradiata), flatfish (Paralichthys olivaceus) etc., are cultured in temperate waters, such as in China, DPRKorea, ROKorea and Japan.Proper site selection for marine netcage culture is of paramount importance as it may considerably affect construction, costs, operating costs, growth and survival rate of the fish, and the period of usefulness of the cages. Although floating cages can be usually towed away, sometimes it is not economical to do so.Site selection criteria also serve as a technical guideline for the production of seafarming resources atlas, rules and regulations, which are necessary for planning seafarming development programme in each country. The guidelines considered in this paper are broad and general, which may have to be modified to suit local conditions and species to be cultured in each area.Prior to the establishment of a cage culture system, an extensive knowledge of the environment of the site is required by studies and analyses of field survey works, existing data provided by government, available literature and consultations with the local people. As mentioned above, there are two types of marine finfish netcage culture which are commonly practiced in the Asian region. One is the floating type which has the advantage of being movable and having more potential in deeper waters. The other is the stationary type which is suitable for small-scale farmers due to its low construction cost. Expectedly, not all of the technical criteria of site selection would apply similarly to both forms. The criteria for site selection of marine finfish netcage culture are summarized in Table 1.
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