7 ranged from 5 to 8 pounds and 5 ranged from 

 10 to 32 pounds. 



There is considerable diversity in the pro- 

 portion of males and females between schools. 

 For example, 1 1 females and o males were caught 

 from a school of 5- to 9-pound fish on August 8, 

 1951. In contrast, of 31 fish taken from a school 

 of 5- to 9-pound fish on July 12, 1954, 29 were 

 females and only 2 were males. 



and crustaceans. This is in agreement with 

 the results of other investigators who have 

 noted the stomach contents of these same pelagic 

 species in Hawaii andelsewhere (Imamura 1949, 

 Nakamura 1949, Reintjes and King 1953, Ron- 

 quillo 1953, Shapiro 1948, Welsh 1949a, and 

 others). A discussion of the food of each species 

 follows . 



Skipjack 



Other Fish 



We have few data on frigate mackerel and 

 wahoo. It might be noted, however, that the 17 

 frigate mackerel, which were all about 1-1/2 

 pounds in weight, were mostly at stages 2 and 3, 

 but included one male (2-1/2 pounds) classed as 

 "mature." The 8 wahoo, which ranged from 20 to 

 33 pounds, were mostly at stage 2, but the largest 

 specimen, a female, was classed as "mature." 



FOOD 



The results of the stomach analyses for 

 skipjack, little tunny, yellowfin, and dolphin are 

 presented in tables 11, 12, 13, and 14, respec- 

 tively. The numbers of stomachs examined were 

 as follows: 67 skipjack, 32 little tunny, 15 

 yellowfin, 52 dolphin, 3 wahoo, and 2 frigate 

 mackerel. The stomach collections were made 

 in 1951, 1952, and 1953. 



The advantages and disadvantages of the 

 various methods of evaluating food components 

 have been discussed by Reintjes and King (1953). 

 They conclude "....that those food items that 

 rank large in number, large in volume, and high 

 in frequency of occurrence are important foods — 

 at the time and in the area sampled. " Data for 

 all three of these methods of analysis have been 

 incorporated into the above-mentioned tables. 



For skipjack ranging in size from 40. to 

 61.1 cm. the most important food item by vol- 

 ume appeared to be cephalopods (squid), with 

 fishes second in importance (table 11). Not only 

 did squid comprise the largest volume, but the 

 numbers found were also high, lending further 

 support to their importance. This is in contrast 

 to results which were obtained by Welsh (1949a) 

 from samples collected in waters adjacent to 

 Oahu but not confined to the area delineated in 

 figure 1. In 21 stomachs he found fishes to be 

 the most important food by volume. In our 

 samples fishes did have the highest frequency 

 of occurrence. 



Of the crustaceans the stomatopod larvae 

 comprised the largest volume and highest 

 occurrence. Some of the skipjack were found 

 to be gorged with stomatopods. Some were also 

 found to be gorged with crab megalops. 



Little Tunny 



The results for the little tunny ranging in 

 size from 31.2 to 66.8 cm. show that fishes 

 comprised the greatest volume of food with 

 crustaceans next in rank (table 12). The 196 

 samples examined by Welsh (1949a) for this 

 same species showed just the opposite. 



Gorging on stomatopods and crab megalops 

 was also observed for the little tunny. 



In identifying the ingested fishes, the 

 following references proved to be helpful: 

 Brock (1950), Jordan and Evermann ( 1905), and 

 Smith (1949). The scientific names of the food 

 fishes referred to in this report are for the most 

 part in accordance with Brock (1950). Identifi- 

 cation of the invertebrates was aided by reference 

 to Berry (1914), Edmondson (1946), Hiatt (no 

 date), and Townsley (1950). 



We wish to thank Drs. A. H. Banner and 

 D. W. Strasburg for their help in the identifica- 

 tion of various organisms found in the stomachs. 



The food of these troll-caught fishes is 

 composed almost entirely of fishes, cephalopods. 



Yellowfin 



In the food of yellowfin ranging in size from 

 47. 4 to 58. 9 cm. , squid provided the greatest 

 bulk (table 13). Welsh (1949a) also found that 

 squid were important as food for yellowfin 

 around the island of Oahu. Reintjes and King 

 (1953) found that cephalopods were relatively 

 unimportant in the food of yellowfin caught at the 

 surface near land in the region of the Line and 

 Phoenix islands. 



The presence of seahorses (Syngnathidae) 

 in the stomach contents of yellowfin in Hawaiian' 

 waters has been previously reported by Herald 

 (1949). As seen in table 13, seahorses were 



17 



