in Japan, puffers are completely safe to eat. 



Production of puffers in fish farms has decreased 

 during recent years because of a shortage of seed- 

 lings, as indicated in the following table: 



The farming of puffers is generally carried out in 

 the warmer part of Japan since the puffers require 

 water temperatures between 10°and 29°C. Of the 14 

 management units in Japan, 8 are located in the Seto 

 Inland Sea. 4 in the west Japan Sea area, 1 in the 

 east China Sea, and 1 in the north Japan Sea area. 



Traditionally, puffer farming depended on the 

 capture of partially grown fish in the spring, rearing 

 these fish to market size in net enclosures, and mar- 

 keting them in the winter when demand and price 

 were high. Larger fish, 40-60 cm in length, weighing 

 1.5 to 2.5 kg, can be fed in enclosures from spring to 

 early winter and then shipped to market. Younger 

 fish, about 200 g when captured, require another 

 year before reaching market size. 



Methods for artificial propagation of puffers were 

 developed in Japan in 1960 and are now used com- 

 mercially. Seedling fish of about 3 g are transferred 

 from the hatchery to the growing net cages in July 

 and should average 550 g by August of the following 

 year. At the end of \V2 yr, the puffers should reach 

 800 g, the minimum market size, and after one addi- 

 tional year should weigh 1.5-2.0 kg. 



The procedures for rearing puffers are similar to 

 those used in the culture of yellowtail. Since both of 

 these fish are carnivorous, fresh or frozen fish, such 

 as horsemackerel. mackerel, anchovy, sand eel, and 

 saury are used for food. Minced flesh is recom- 

 mended for fish less than 100 mm in length, but larger 

 fish can be fed chopped flesh. 



The fish are fed 4 times a day during midsummer, 3 

 times a day from September to November, and less 

 frequently during the winter and early spring. Puf- 

 fers stop feeding in winter when the water tempera- 

 ture falls below 1 4°C , and this causes a weight loss of 

 about 109?- during the winter. 



Expansion of puffer farming will require greater 

 production of seedlings through artificial propaga- 

 tion. Detailed description of procedures used in the 

 farming of puffers is gi\en by Fujiya in his 1969 

 paper. "" Farming Fisheries in Japan." 



BLACK PORGY CULTURE 



The Japanese black porgy, or sea bream, Mylio 

 macrocepluiliis (also listed as Acanthopui^riis 

 schlegelii), is a nonmigratory species found in shal- 

 low water along the coasts of Japan, Korea, Taiwan, 

 and China. The annual catch of this species in Japan 

 is 3,600-3.900 tons, about 65% of which is landed in 

 the Seto Inland Sea (Fujiya, 1969). Black porgy can 

 be raised in floating net cages or seawater ponds; 

 and. since this species is more resistant to lower 

 temperatures than some other species which are 

 used in aquaculture, the geographical range suitable 

 for farming is greater. Black porgy are reported to 

 stop feeding at water temperatures below 10°C but 

 can survive temperatures several degrees colder. 



The species is omnivorous, feedling on mollusks, 

 crabs, polychaete worms, and seaweeds, so a vari- 

 ety of waste fishes and unutilized mollusks can be 

 used as food. With the conversion rate of 3 or 4:1 in 

 experimental scale farming reported by Fujiya 

 (1969) forfresh fish diets, commercial culture should 

 be economical. Market size fish reportedly can be 

 produced within 16 to 20 mo. 



Black porgy farming using "natural seedlings" is 

 of two types, depending on the size fish which can be 

 obtained. Small seedlings, 1 to 4 cm in length, are 

 caught along the coast by seines from late May to 

 late July. These small fish are put in fine-mesh float- 

 ing cages for 1-2 mo and then transferred into larger 

 mesh net cages. Market size fish, about 150 g, can be 

 expected within 15-18 mo. 



The second type of farming depends on capture of 

 seedlings, 10-15 cm in length (30-50 g in weight), in 

 set nets or by angling from May to July. Fish of this 

 size will reach market size after about 6 mo of feed- 

 ing in floating net cages. 



The limiting factor in farming of black porgy is the 

 supply of seedlings from natural reproduction. 



Methods for artificial propagation of black porgy 

 have been developed in Japan and with a suitable 

 increase in production of seedlings, porgy farming 

 can be greatly expanded. Further details concerning 

 the farming of black porgy are given by Fujiya 

 (1969). 



RED PORGY CULTURE 



The red porgy or sea bream, Chrysophrys (Piii;- 

 nis) major, known in Japan as the "tai" or"madai" 

 is in great demand since it is the traditional fish 

 served at celebrations. The commercial catch of sea 



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