Saito, S. 1973. Studies on fishing of albacore, 

 Thunnus alalunga (Bonnaterre) by experimental 

 deep-sea tuna longline. Hokkaido Daigaku, 

 Sapporo, Jpn. Mem. Fac. Fish. 21 (2 ): 107-184 . 



Results of hook rate by depth experiments: 

 Albacore were most dense between 200 and 260 

 m and sometimes more dense between 280 and 

 300 m than in layers above 200 m. The paper 

 deals mostly with design and operation of 

 longline gear intended to fish deeper layers 

 than conventional gear. Albacore occurrences 

 coincided with a "discontinuous" surface 

 against the low salinity water mass of the 

 200 to 400 m level. 



KEY WORDS: albacore, depth, season, discon- 

 tinuity. 



Saito, S. , K. Ishii, and K. Yoneta. 1970. Swimming 

 depths of large sized albacore in the South Pacif- 

 ic Ocean - I. Fishing of albacore by a newly de- 

 signed vertical longline. Jpn. Soc. Sci. Fish. 

 36 (6) : 578-584. 



A study of the swimming depths of albacore 

 using a vertical longline. Results confirmed 

 the hypothesis that albacore are among the 

 deeper swimming tunas. Hook rates approxi- 

 mated 4.7-5.4% at 200-300 m and even 3.4% at 

 380 m. 



KEY WORDS: tuna, albacore, depth, habitat. 



Saito, S, and S. Sasaki. 1974. Swimming depth of 

 large sized albacore in the South Pacific Ocean - 

 II. Vertical distribution of albacore catch by an 

 improved vertical longline. Bull. Jpn. Soc. Sci. 

 Fish. 40 (7) :643-649. 



Experimented on depth of catch with a verti- 

 cal longline west of the Fiji Islands. Alba- 

 core highest hook rates were at 200 to 300 m, 

 and at the 380 m layer they were higher than 

 that at 150 m. Bluefin greatest catch rates 

 were at 300 m and deeper; yellowfin greatest 

 catch rates were at less than 200 to 300 m. 



KEY WORDS: tuna, albacore, bluefin, yellow- 

 fin, depth, distribution, catch, habitat. 



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