462 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



Table 1. — Atbacore stomachs collected from the central and northeastern Pacific from 1950 to 1957 by vessels of the 

 Bureau of Commercial Fisheries Biological Laboratory, Honolulu, according to cruise, time of year, locality, 

 fishing method, and place of examination 



Vessel 



Cruise 

 number 



Cruise period 



Collecting area 



Range of latitude 



Range of longitude 



Fishing 

 method 



Percent of 



catch 

 examined 



Iluph M. Smith.., 

 Hugh .\[. Smith... 

 John R. Manning. 

 John Ft. Manning. 

 John F. Manning. 

 John F. Manning. 

 John F. Manning. 

 John /?. Manning. 

 John F. Manning. 

 Charles II. Gilberl. 

 John F. Manning. 

 John R. Manning. 

 Charles H. Gilbert. 

 John R. Manning. 



Hugh M. Smith... 

 John R. Manning. 

 Hugh A/. Smith... 

 John F. Manning 



Charles H. Gilbert. 



John F. Manning 



Charles H. Gilbert. 

 Charles H. Gilbert. 



John R. Manning 

 John F. Manning 



32 



June-Aug. IS.'iO 



Aug.-Oct. 1961 



Jan.-Mar. 1952 



Oct.-Dec. 1962 



Jan.-Mar. 1953 



Apr .-June 1963 



July-Sept. 1953 



Nov.-Dec. 1953 



Jan.-Mar. 1954 



Feb.-Apr. 1954 



May-June 1954 



Sept.-Nov. 1964.--- 



Sept.-Nov. 1964 



Dec. 1954-Feb. 1955 



Jan.-Feb. 1956 



May-June 1966 



July-Aue. 1955 



July-Sept. 1965 



Sept.-Nov. 1955.--. 



July-Sept. 1956 



Aug.-Sept. 1956 



Oct.-Dec. 1966 



Oct.-Dec. 1956 



June-Aug. 1957 



3° S 



1" N.-2° S . . 

 3° N.-8° S.... 

 2° S.-5° S._., 

 1° S.-16°S... 

 3° N.-T" S.... 

 3° N.^° S.... 

 5° S 



31° N.-36°"n: 

 2" N.-9° S... 



3° N.-0° 



36° N.-46° N 

 37° N.-45° N 

 29° N.-36° N 



32° N.-33° N 



36° N 



46° N.^8° N 

 36° N.^0° N 



41° N.^6° N 



42° N.-49° N 



9° S.-14°S.. 

 34° N.-41° N 



39° N.. 



33° N.-45° N 



171° W- 

 150° W. 

 155° W.. 

 152° W. 

 144° W. 

 150° W. 

 165° W.- 

 155° W. 

 160° W. 

 121° W. 

 167° W. 

 159° W. 

 165° W. 

 169° W. 



•180° 



170° W. 

 ■150° W. 

 •170° W. 

 ■160° W. 



156° W. 

 160° W. 

 176° W, 

 172° E-- 

 180° 



Longline. 



do.... 



do.... 



do... 



do... 



do-... 



do.... 



do.... 



do-.. 



do.... 



.do.. 



.do- 



173° W.-179° E 

 165° W 

 157° W 

 128° W 



145° W. 



129° W. 

 166° W. 



Trolling.. 

 Longline. 

 Trolling -- 

 do-.. 



.do. 



.do. 



146° W.-178° W. 



132° W.-140° W. 

 125° W.-144° W. 



130° W- 



124° W.-143° W. 



Longline, 

 Trolling-. 

 Longline. 

 Trolling.. 

 OiUnet.. 

 Trolling.. 

 Gill net. - 

 Longline. 

 Trolling.. 

 Gill net.. 

 TroUing-. 

 Longline. 

 Trolling.. 

 GiUnet.. 



50 

 100 

 65 

 27 

 62 

 58 

 71 

 50 



42 

 33 

 28 

 50 



100 



100 

 60 

 17 

 2 



100 

 16 

 73 

 10 

 9 

 50 

 11 



100 

 1 



100 

 43 

 97 



I Of this number, 83 were examined at sea. 



were choseii for analysis in the laboratory because 

 they were thought to contain food. However, 

 many of these stomachs were empty or nearly so, 

 and it is considered that any bias introduced into 

 the sampling was slight. 



The reporting of results has followed the ap- 

 proach used by Keintjes and King (1953) and 

 King and Ikehara ( 1956) . This takes into account 

 the number of organisms, the frequency of their 

 occurrence, and their individual and aggregate 

 total volumes. An expression used throughout 

 this report is that of volume (in cc.) of stomach 

 contents per pound of body weight of the individ- 

 ual fish. Since the capacity of an albacore's 

 stomach depends upon the size of the fish, the 

 comparison of the stomach volumes of large and 

 small fish together would tend to bias the data in 

 favor of the larger fish. Figure 3 shows the re- 

 lationship between volume (cc.) per pound body 

 weight and body weight. The points are somewhat 

 scattered and are probably not normally distrib- 

 uted, but there is an indication of an overall de- 

 crease in average stomach content per unit, of body 

 weight with increase in fish size, a situation simi- 

 lar to that reported for yellowfin (Neofhvnniis 

 macropterus) and bigeye {Parafhvnnus sibi) tuita 

 by King and Ikehara (1956). 



' Of this number, 113 were examined at sea. 



en 4 — 



40 50 60 



BODY WEIGHT (LB) 



Figure 3. — Relationship between food volume per unit 

 of body weisht and total bod.v weight of 260 longline- 

 and troll-caught albacore tuna. 



Gill net-caught albacore were not included in 

 figure 3 since a high percentage of their stomachs 

 were empty or nearly so, which may reflect the 

 time of feeding or a variable introduced by the 



