fishing grounds; the vertical changes ?jere slight in comparison irLth the S".no 

 season last year. The water color t^s favorable, but almost no schools Fere 

 seen and the fishing turned out to be very poor. 



Third Cruise 



On July 30 at 9:00 A.M. the vessel departed Misaki and headed directly 

 for the fishing grounds. Operations were begun on August 9 at /!^l" ^5'N, 

 175° A.O'E in a surface T^ater temperature of 18,3°. In the 10 days up to 

 August 18 investigations were made all over the area, but results wer' very 

 poor. The vessel turned southward and on the 21st at 38'^ 30 'N, 177*^ 30 'E a 

 remarkable line of discontinuity Fas encountered rdth a •T.ter temperature of 

 18° on the north side and 25'-' on the south side, ferlin -ere seen leaping 

 on the south side and the lines '^rc inrncdiatoly set. In three sets 10 

 albacore and 116 ncrlin, big -eyed tuna, and other fish '.7cro taken. The total 

 catch for this cinisc amounted to ZU albacore, 6 yellowfin, 52 big-eyed tuna, 

 35 marlin, and 60 sharks. ■ The albacore from the '.rarra-vater zones r^re large 

 fish v*iich averaged 5-6 kan apiece. 



On September 1 the vessel returned to Misaki and landed its catch. 

 Repairs vrere made to the hull, engine, and fishing gear, and on September 

 20 the operations for the year ^erc finished. 



k. Conditions on the fishing grounds 



Current velocities on the fishing grounds xvcro ri'enGrally slovr and the 

 direction of floi7 for the most part agreed vath that shovn on the current 

 charts. Currents were for the most part easterly, and it is thought that 

 the direction and rate of flow T7crc affected by the force and direction of 

 the \7ind. Surface water temperatures ranged from a m;iximum of 25.2° to a 

 minimum of 16.8° vdth an average of 19.1°. At the 100-mctcr level the 

 maximum was 20.0°, the minimum -^as S.g'', and the average v/as 12.5°. Vertical 

 changes in teraperatur- were slight as compared to the same season of the 

 previous year. On the third cruise areas of whitish turbid water were fre- 

 quently seen north of 3ii.°N. 



5. Relationships betv7ccn schools and signs of life on the sea, bait-taking 

 and the condition of the schools, and weather and c\irrents and bait-taking 



There i?rero many sea-birds (commonly called otori ) in the assigned 

 survey area, but throughout the investigation the iikita I">ru caught only U^ 

 albacore. No albacore schools were scon, but small schools of skipjack and 

 dolphin were frequently sighted. Bait-takiag was generally good when there 

 ^Tas a slight chop on the surface. 



6. Methods of preserving bait and the relationship of freshness to bait- 

 taking 



a. Methods of preserving bait 



Frozen squid, mackerel, and sardines and salted mackerel and sardines 

 were used for bait. The frozen baits were krpt in a cold storage space 

 where the temperature was maintained at 5° - 10° belov; zero. The salted 



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