Report of the Results of Albacorc Fishing 

 Ground Development 



Akita Prefecture Fisheries Experiment Station 



1. Vessel - /kita Maru 



2. Type of operation - Albacore fishing ground exploration 



3. CXitline of operations 



The second summGr investigations for the development of albacore 

 fishing grounds '.rerc carried out in continuation of those of the preceding 

 year and in cooperation mth a number of other prefectures. 



The i^cita Maru, upon completion of the investig-^.tions of the i/?inter 

 tun^ Itngline fishing grounds, 'tts doeked at the Tokai Shipyard near 

 Shimizu on April 10 in order to prepare for the operations. Repairs were 

 made to the hull and engine, and fishing gear "/as construct-^d and repaired. 

 On May 11 the vessel was undocked and sailed to Flsaki where bait, fuel, and 

 ice were taken aboard. 3Eth all preparations complete she departed Misaki on 

 May H, for her first cruise. Thereafter three exploratory cruises were 

 made by September 1. After the completion of the survey irnvk the restora- 

 tion of the hull, engine, and fishing gear wns undertaken, and all operations 

 were finally finished on September 20, An •utline of the results of each 

 cruise follows. 



First Cruise 



On May 1^ at 8:50 A.M. the vessel departed Misaki and at 11:30 she 

 turned eastward from her c-ourse paralleling Nojimasaki and headed directly 

 for the fishing grounds. Investigations v;ere begun on May 25 in an area 

 with a surface temperature of 20.5'^ at 31° 32 'N, 179° 37 'T7. No albacore 

 were taken at the first to third fishing stations. The first ones caught 

 were four fish taken on the fourth trial at 3^^ 26 'N, 177^ 5'W, From 9 

 stations fished up to June A the catch '.vas 12 albacore, 13 big-cyod tuna, 5 

 marlin, and U9 sharks. On June 13 the vessel returned to Misaki, concluding 

 the first cruise. 



Second Craisc 



The vessel departed Tatcyama on June 20 at 12:20 P.M. -^nd at 2:37 P.M. 

 the c»ursc v.ras changed from one paralleling Nojimasaki to an east by slij^htly 

 north course for the fishing grounds. Investigations verc begun on July 1 

 in an area vdth a surface temperature •f 20° at 36° 32 'N, 176° 18 'E. In 10 

 trials made up to July 10 all parts of the assigned area were investigated, 

 but the «atch amounted to only the extremely poor figure of A albacore, H. 

 big-eyed tuna, 20 marlin, and 77 sharks and other fish. Because of the lo'/ 

 fuel supply the vessel began its return voyage on July 10, arriving at Misaki 

 July 21 to conclude the second cruise. 



Average vnter temperatures on the fishing grounds during this cruise 

 were 19.5° on the surface, 17.9° at 50 meters, and 15.5° at 100 meters. 

 Temperature changes vdth depth were very similar to those on the "Inter 



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