ones from 15 to 30 kilograms in weight. As the vessel proceeded northvR.^.rd 

 the surface water temperatures fell oo between 1A° and 16° and in these 

 areas no striped marlin or big-eyed tuna were caught and the albacore Ti^ich 

 were taken wore small ones of about 6 to 10 kilograms. Small albacore vrerc 

 seen Jumping from time to time during operations, but none were taken on 

 the trolling lines, 



U, Conditions on the fishing grounds, direction and speed of currents, 

 water temperatures, nnd water color 



First Cruise 



The area surveyed was comparatively small in extent, lying between 

 32-35°N and west of 18C°?1, The currents were for the most part southerly 

 and very weak, the hiphest ■"•elocity measured being about 0.6 knot, J^t the 

 beginning of cperatiou.s a northeasiierly current was felt. Surface water 

 temperatures on the fishing grounds were generally variable, but the changes 

 were relatively small, Tomporatui-es v«re from 17,. 8° to 19.7° and they 

 dropped progressively by 1° to 3° at each of the prescribed lov/er levels. 

 The 100-raeter level at all fishing grounds shored 14-. 5 to 16°, While 

 fishing the direction of the lines occasionally changed markedly, and lines 

 of discontinuity were frequently encountered. The v/ater color was generally 

 favorable, but with changes in the temperature while fishing, and of course 

 while cruisin{j there were changes in the color. Plankton was particularly 

 abundant. Transparencies of 20 to 30 meters were measured. 



Second Cruise 



Compared to the previous ciniise the survey area was larger in extent. 

 It was almost the same area as that covered in the second cruise of the 

 previous year except for a northward shift of one degree of latitude. 

 Currents were southwesterly and northeasterly, and they were generally slow 

 with one knot the highest velocity encountered. At several of the H 

 fishing stations no current could be detected. Surface water temperatures 

 where albacore were taken were from 15.7° to 21°. As the vessel moved 

 south the temperatures rose to 23° or higher and no albacore were taken at 

 all. Temperatures at the lOO-mcter level were 11,20 to 1^,8° and the 

 difference between temperatures at the prescribed levels was 1° to 2°, Wate1| 

 color was generally favorable, but there were some areas whore the trans- 

 parency was remarkably poor, the range being from 10 to 27 meters. Plankton 

 was abundant all over the survey area. 



Third Cruise 



The survey area lay north of ^° between 175°E and 178°W, and experi- 

 mental fishing was carried on over a rather broad range. The currents were 

 extremely complex, there wore many lines of discontinuity, and there were 

 some areas where gyrals were formed. Both northwesterly and southeasterly 

 currents were present, and a maximum velocity of 0.9 knot \-ns measured. 

 No current at all could be detected at 2 out of the 1^ stations fished. 

 Surface water temperatures were from 1/^9 to around 21°, and changed every 

 30 or iiO minutes while the ship was under way. It was felt that perhaps the 

 zone of /^ s\iitahle_y water in this area is narrow from east to west and 



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