Kanagawa Prefectural Fisheries Experimental Station. 

 1961. Analysis of hook rate of pelagic tuna fish- 

 ing boats in_ Japan, 1958. [In Jpn.] Kanagawa 

 Suishi Shiryo (Rep. Kanagawa Pref. Fish. Exp. 

 Stn.) 3, 47 p. 



Catch and efforts statistics of Japanese 

 longline boats by month, area, and species. 

 Includes water temperature data. 



KEY WORDS: tuna, catch, distribution, 

 season, temperature. 



Kawai, H. 1959. On the polar frontal zone and its 

 fluctuation in the waters to the northeast of 

 Japan (III). Fluctuation of the water mass dis- 

 tribution during the period 1946-1950 and hydro- 

 graphic conditions in the fishing grounds of skip- 

 jack and albacore. [In Jpn., Engl, summ.] Bull. 

 Tohoku Reg. Fish. Res. Lab. 13:13-59. 



Seasonal changes in skipjack concentrations 

 relative to oceanographic conditions. Con- 

 cluded that size of fish differed in accord- 

 ance with temperature and chlorinity on the 

 albacore grounded. 



KEY WORDS: tuna, skipjack, albacore, ocean- 

 ography, temperature, salinity, depth, 

 fronts, water masses, season. 



Kawai, H., and M. Sasaki. 1962. On the hydrographic 

 condition accelerating the skipjack's northward 

 movement across the Kuroshio Front. [In Jpn., 

 Engl, summ.] Bull. Tohoku Fish. Res. Lab. 20:1-27. 



The primary Kuroshio front and the sharp 

 thermal gradient along it prevented skipjack 

 from moving northward. Both the primary and 

 a secondary front influenced the movement of 

 the main body of skipjack into the Japanese 

 fishery. 



KEY WORDS: tuna, skipjack, migration, sea- 

 son, front, currents. 



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