Table 4. --Tuna catch by hook and line fisheries in 

 various localities (1941, Ministry of 

 Agriculture and Forestry statistics) 



4. Longline fishery 



The longline fishery is the most important of the tuna fisheries, both in terms of the 

 scale on which it is prosecuted and in terms of the catch. 



The gear is built around one trunk line to which float lines ( ukinawa or abanawa) and 

 branch lines are fastened. In the old days hemp was used as material for the lines, but at 

 present cotton is generally employed. The gear used in the spear-fishery of Kagoshima Prefec- 

 ture employs lines of about 7 momme weight, but ordinarily 9 momme or 10 momme line is 

 employed. This designation shows the weight in monnme of five shaku of line (I momme = 0. 1325 

 ounce, 1 shaku = 1 foot). 



The thickness of the line used has gradually increased in recent years, the main 

 reason being the increase in the size of fishing boats with the increase in the nunnber of units of 

 gear used as another reason. At the end of the branch line a sekiyajna is attached with a swivel. 

 Formerly the sekiyama was made of a heart of high-grade Noshu hemp wound with cotton line, 

 but at present this is hardly used at all, the ordinarily employed sekiyama being made of nine 

 strands of No. 28 steel wire wrapped with cotton. A wire leader is attached to the end of the 

 sekiyama. This leader is usually nine strands of No. 27 steel wire, but some fishermen claim 

 that seven strands of No. 25 wire is best. The hook is attached to the end of the leader wire. 



A glass ball 30 cm in diameter, with walls 8 mm thick, wrapped in netting, is 

 attached to the float line as a float. Sometimes billets of paulownia wood about 3 inches in diam- 

 eter are used as floats. In recent years iron or aluminum ball floats have come into use. The 

 floats combine the functions of supporting the line, signaling the presence of fish on the line, and 

 identifipation. The float functions and the marker functions are the most important. Ordinarily 

 a flag of cloth or of palm fiber is attached to a bamboo pole to mark the float. At night in order 

 not to lose sight of the line, light buoys are attached here and there. Formerly carbide lamps 

 were used for this purpose, but at present battery-powered lights are generally used. As the 

 disappearance of the line means a very serious loss, recently such plans as the attachment of a 

 device to the float to transmit electrical waves which could be received by the fishing boat have 

 been devised zind will probably be put into actual use in the near future. 



The construction of the lines varies depending on the type of fish sought, the 

 locality, or the individual fisherman, but the basic form is invariable. In any case there is a 

 single main line with a number of branch lines and float lines made so as to hang the hook at a 

 suitable depth. 



10 



