2o Where currents meet and intermingle 



For example, the waters northeast of Halmahera (discovered by the 

 Zuiho Mara in March 194-1) y Fishing Ground C^ part of Fishing 

 Ground D 



3., At the ends of branches of the Counter-current 

 For example J the coastal waters east of Falau 



4.0 Where the Counter-current system is narrow 



For example, the waters 6OO miles south of Saipario Fishing 

 Ground Ao Fishing Ground B„ 



5o Wnere oceanographic conditions are favorable along the edges of 

 the Counter-current 



For example, the waters 300 miles south of Palau« Fishing 

 Ground G, The waters 150 miles south of Jaluit (discovered by 

 the Zuiho Maru in November 1940). The waters 300 miles south- 

 west of Ponape (discovered by the Zuiho Maru in November 194-0) o 



The above is a general explanation from the point of view of the form 

 of the current area of the Counter-currento The locations of the grounds 

 can thus be found on the North Pacific Current Chart (published by the 

 Hydrographic Office), but it goes without saying that they are always 

 changing, and such locations as the outer edges of bends in the ciirrent 

 area (water system) can easily shiftc Consequently it is necessary to 

 proceed to the area and then make a test set of the longline in order to 

 determine the direction of the current. For example 5, a place where a 

 southeasterly current turns to the northeast or vice versa can be assumed 

 to be a bend in the current. 



(II) Good fishing grounds from the point of view of oceanographic condi" 

 tions (sea conditions) 



The good fishing grounds as defined by the form of the current are 

 cf course included in the good fishing grounds defined from the point of 

 view of oceanographic conditions, but the former have been described 

 separately above in order to facilitate the reader's understanding of the 

 sub:eoto The author will now explain good fishing grounds from the point 

 of view of oceanographic factors cm the basis of the results of investi- 

 gations which have been made in the past, the data from which he has at 

 hand. The good fishing grounds described above are naturally charac- 

 terized by these favorable oceanographic factorSo 



lo Velocity of the current 



Within the Equatorial Counter-current the most suitable velocities 

 are from 0^5 to loO knot. Few fish are taken in water systems which 

 have excessively slow speeds of less than Oo5 knot or in strong currents 

 of over 1. 5 knotSo 



On this score the aforementioned Fishing Ground F, which is located 

 southeast of Palau on the outer side of a bend in the Equatorial Counter- 

 current, is a good fishing ground. Of course it also exhibits the other 

 favorable oceanographic features^ Locations in the main stream at the 

 center of the Countercurrent where the velocity of the current is around 

 2o0 knots or more are not good fishing grounds. 



