from Hawaii . The pectoral fins of Polynesian 

 yellowfin are also much longer than those on yel- 

 lowfin tuna of comparable size from Costa Rica 

 and significantly longer than those from Hawaiian 

 waters. 



With respect to morphometric measure- 

 ments of head length and snout to fin insertions, 

 Polynesian specimens appear to be intermediate 

 between specimens from Hawaii and Costa Rica . 

 In several characters (head length, snout to in- 

 sertion of first dorsal, snout to insertion of 

 second dorsal) the Polynesian specimens do not 

 differ significantly from Costa Rican material 

 but are different from Hawaiian specimens. In 

 one morphometric measurement, however, dis- 

 tance from snout to anal insertion, the Polynesian 

 yellowfin differ significantly from Costa Rican 

 specimens but do not differ from Hawaiian fish. 

 Gill raker counts from Polynesian tuna are iden- 

 tical with those reported by Schaefer for Costa 

 Rican material (average total count of 30 60 on 

 first arch), but nearly a gill raker higher than 

 average counts of 29.66 gill rakers found for 

 Hawaiian yellowfin. This is further evidence of 

 the heterogeneity of the yellowfin tuna stocks of 

 the Pacific . 



The extent of the intermingling of tuna 

 stocks in the Pacific can only be determined from 

 an extensive tagging program . Tuna tagging was 

 tried by Godsil (1938) as early as 1934-38, when 

 4,000 yellowfin and skipjack were marked with a 

 preopercular strap tag . Only a single yellowfin 

 tuna was recaptured, one day after release. A 

 tuna marking program was reactivated by mem- 

 bers of the California Department of Fish and 

 Game in early 1952, and the marking methods 

 and recoveries were reported by Wilson (1953) . 

 During 1952 and 1953, 1,950 yellowfin and 590 

 skipjack were tagged with the newly developed 

 streamer-type vinylite -tubing tags. There were 

 14 recoveries of yellowfin reported by Wilson, 

 two of which were caught 204 and 253 days sub- 

 sequent to tagging. The areas of release and 

 recovery were not given . Although tuna tagging 

 has been intensified since Wilson's report, there 

 have been no further reports on the experiments . 



Albacore , Germo alalunga 



Godsil (1948) made morphometric compar- 

 isons of albacore from three areas of the north 



Pacific: from off the west coast of America, 

 from the vicinity of the Hawaiian Islands and 

 from the vicinity of Japan. Over 100 specimens 

 of albacore from American waters were studied, 

 but the sample from Hawaii consisted of only 

 three fish and the samples from Japan of only 

 nine fish. Fourteen morphometric measurements 

 were made on each fish. The number of American 

 specimens was sufficient for making regressions 

 of each character on standard length, the few 

 Japanese and Hawaiian specimens were simply 

 compared with these regressions. Godsil found 

 that the Japanese specimens differed significantly 

 (probability below the 1% level) from the American 

 specimens in ten of the 14 characters studied. 

 The Japanese specimens had a shorter head and 

 caudal region than the American material, the 

 body was relatively deeper, the first dorsal fin 

 was higher, the eye was larger, and the pectoral 

 fin was proportionately longer . Godsil found the 

 three Hawaiian specimens to be more closely re- 

 lated to the Japanese than to the local population. 

 A conclusion arrived at by Godsil from his com- 

 parisons was the following: "The local and 

 Japanese populations of albacore are probably 

 distinct and non -intermingling." 



There have been several attempts to trace 

 the movements of albacore by tagging experiments . 

 Godsil, during the tuna tagging program of 1934- 

 38, tagged 70 albacore according to Wilson (1953). 

 This was not mentioned by Godsil (1938) . The 

 fish were tagged on the preoperculum with a strap - 

 type metal and celluloid tag. The Fisheries 

 Research Board of Canada (British Columbia) tagged 

 140 albacore in 1948 and 355 in 1950. The first 

 group was tagged with a celluloid button-type tag 

 inserted in the caudal fin, the second group was 

 marked with a hook tag. There have been no re- 

 coveries. The North Pacific Exploratory Program 

 of the U. S. Fish and Wildlife Service tagged 621 

 albacore during 1950-1952 using Peterson -type 

 tags and streamer tags. There have been no re- 

 coveries. Alverson and Chenoweth (1951) con- 

 ducted water tunnel tests on different types of fish 

 tags inserted on albacore . They found that 

 streamer -type tags were the most successful of 

 the kinds tested. The California Department of 

 Fish and Game began marking albacore with 

 vinylite -tubing tags in 1952. There have been a 

 number of recoveries. 



An albacore tagged on August 4, 1952 at 



62 



