hooks) are scattered throughout the areas fished 

 in all quartei-s of the year. A tabulation of the 

 data by 5 degrees of latitude (table 3) indicates no 



well-defined seasonal and geographical differences. 

 Average catch rates declined slightly, however, 

 in 1965 as compared with 1963. 



Table 3. — Quarterly mean catch rates (number of fish per 100 hooks) of albacore and (in parentheses) the fishing effort (number 

 of hooks) in the central and eastern South Pacific Ocean (long. 170° E. to 120° W.) 



[From data of American Samoa-based vessels] 



Item 



Latitudes (S.), west of long, 150° W. 



Latitudes (S.), east of long. 150° W. 



0°-5° 



ir-16° 



16°-20° 21°-25° 26°-30° 3r-36° Mean 5°-10° 11°-15° 16°-20° 21°-25° 26°-30° 31°-35° Mean 



1963: 

 Jan.-Mar, 



Apr.-June 

 July-Sept 

 Oct.-Dec 



6.0 5.4 



(14. 390) (2, 600) 



3 8 14 4.9 



(15l!765) (3,080) (2631370) 



4.4 4.4 4.1 6.2 . 

 (766, 280) (280, 592) (103. 045) (212, 192) 



4.5 4.4 4.4 4. 4 . 

 (838,114) (363,583) (19,420) (89,752) 



5.9 

 (9,000) 



6.0 5.8 



(85, 455) 

 4. 2 - 3. 5 6. 3 



(22,786) (86,780) 

 4. 6 5. 2 5. 7 



(48, 836) (909, 246) (195, 

 3.9 1.7 5.2 5. 



(22, 385) (670, 923) (230, 336) 



7.6 



(31,260) 



4.3 7.9 . 



(7,935) (295,362) 



4.1 5.5 6.2 . 



■83) (15, 575) (30,140) 



6.7 

 5.5 

 5.1 



4.2 



Mean. 



4.5 



4.7 



3.9 



4.3 



4.8 



6.9 



3.5 



6.8 



5.4 



1964: 

 Jan.-Mar. 



Apr.-June - 

 July-Sept.. 

 Oct.-Dec. . 



1.5 4.4 



(8, 268) (862, 704) 

 2. 3 5. 



(6,100) (1,902,756) 

 3. 4 4. 2 



(15,158) (347,279) 

 4.4 



3.4 



(253, 000) 



4.6 

 (97, 870) 



4.4 

 (299, 406) 



4.9 



3.3 



(285, 409) ' 



4.7 



(27, 030) 



1.9 



3.1 



1.6 



(1,338) 

 7.0 . 

 (12, 650) 



1.7 



2.8 



(167,910) (1,706,235) 



(3, 830) (111, 030) (636, 836) 



6 3 2 9 3 1 



(141^804) (47^896) (20^172)' 



4.6 



(78,968) (63,780) 

 4. 1 4. 8 



(73,908) (164.804) 

 3.6 4.4 



4.3 4.1 .6 2.4 1.0 



(306, 611) (109, 120) (3,838) (4,296) (6,000) 

 4.6 



1.3 . 



(9, 120) 

 6.6 



(43, 866) (191, 028) (279, 708) 



2.5 



Mean. 



4.5 



4.3 



3.8 



3.0 



4.6 



4.1 



4.5 



3.7 



1966: 

 Jan.-Mar. 



Apr.-June . 

 July-Sept.. 

 Oct.-Dec. . 



. 3.9 4.2 



(296, 751) (1,421, 063) 

 . 2. 6 4. 3 



(74, 692) (2, 708, 555) 

 . 2. 7 4. 



(63, 400) (970, 613) 



.2 3.0 



(22, 420) (380. 594) 



3.8 4.2 



(568. 327) (74. 584) 



4.7 3.1 



(137,720) (6,420) 



(447^ 249) (38', 976) (249, 438) (739', 899) " 

 4.1 4.0 3.7 3. 7 . 



(910, 655) (1, 327, 684) (100, 038) (111, 977) 



1.7 



(1, 620) 



4.3 



2. 5. 



(3, 120) (836, 168) 

 5. 5 5. 6 



(124, 124) (242, 129) 

 3.3 4.8 



(109, 834) (566, 903) 

 1.7 5.4 



2.4 



(24. 930) 



4.3 



(3, 120) 

 2.0 



(5, 894) 

 4." 



(1,458) (699, 574) (518, 535) 



6.6 



(172, 690) 



4. 9 5. 



(5,170) (3,600) 



3. S 7. 2 . 



(2,700) (11,230) 



7.7 

 (13, 836) 



4.6 



Mean. 



2.4 



3.9 



4.1 



3.6 



4.1 



4.9 



3.1 



5.2 



3.4 



4.4 



6.3 



7.7 



To gage the abundance of albacore in areas not 

 fished by the American Samoa-based vessels, some 

 Japanese data were tabulated (table 4). Data for 

 1958-63 indicate that albacore are not as abundant 

 in the western South Pacific Ocean, between long. 

 140° E. and 180°, as in areas fished by vessels from 

 American Samoa. The catch rates, averaging less 

 than two albacore per 100 hooks, are lower than 

 those in more eastern waters. Perhaps some of the 

 difference may be due to the selective fishing for 

 albacore by American Samoa-based vessels, 

 whereas in more western areas, the vessels from 

 Japan may be fishing primarily for other species. 

 Subtle differences in the fishing gear, such as in the 

 lengths of the various lines, are known to affect the 

 catch rates of albacore. It is probable, however. 



that these catch rates reflect the actual abundance 

 of albacore in these areas. 



Seasonally, the best catch rates in tlie western 

 South Pacific are obtained in May through Sep- 

 tember. Latitudinally, the mean catch rates in- 

 crease southward from the Equator, and the best 

 catches are generally made between lat. 15° and 

 30° S. Koto (1966) found the best catch rates in 

 the South Pacific during 1950-61 between lat. 10° 

 and 30° S. and reported peaks of abundance along 

 lat. 20° S. The catch rates south of lat. 30° S. 

 were lower. In the areas fished by the American 

 Samoa fleet, the catch rates are also low near the 

 Equator but do not change as markedly from 

 noith to south. Generally, catch rates are also 

 higher in the southemmost areas fished, between 

 lat. 25° and 30° S. 



62 



U.S. FISH AND WILDLIFE SERVICE 



