1973 



1974 



1975 



100 



50 



"" 100 



CL 

 IT 



D 

 U 



" 50 





 100 



-I 1 r- 



73 92 cm 



-I ^ 1 r- 



50 



33 52 cm 



N 66 



-■ 1 1 1 1 1 1 1 r- 



53 72 cm N - 424 



—I \ \ r- 



«= 199 





S. fja. 



100 



50 





 100 



50 



100 



73 92 cm 



- 53 72 cm 



n 1 \ — 



33 52 cm 



50 — 



-\ 1 r- 



«= 125 



N = 719 



N = 339 



100 



50 



100 



50 



100 



-I 1 1 r 



73 92 cm 



53 72 cm 



yn 



N = 212 



T 1 r- 



N = 1047 



." 2 e 



O O 



D. a 



E 



< 



Figure 2. 



Food Items 



-Percent frequency of occurrence of summer food items within three size groups of pot-caught Pacific cod by year of 



coUection — 1973-75 — near Kodiak Island, Alaska. 



that smaller crustaceans were more commonly 

 found in small cod while a gradual shift to a mixed 

 diet of larger prey (primarily fishes) was noted for 

 the larger fish. Arntz ( 1974) examined juvenile G. 

 morhua, and found the most important food to be 

 small crustaceans, mainly cumaceans (35.6% by 

 weight of the total food consumed); fishes ac- 

 counted for only 15.3% by weight of the total food 

 consumed. This trend of large cod being more pis- 

 civorous than small cod has also been dem- 

 onstrated by Powles (1958) and Rae (1967). 



Acknowledgments 



I am especially indebted to the ADF&G and Guy 

 C. Powell for their assistance in collection of data. 

 Special thanks to Howard M. Feder, University of 

 Alaska, for his editing suggestions. Thanks to 

 John R. Hilsinger, University of Alaska, for allow- 

 ing me to use his Pacific cod feeding data obtained 

 during International Pacific Halibut Commission 

 surveys, and to George Mueller and Kenneth 

 Vogt, both of the Marine Sorting Center, Univer- 

 sity of Alaska, for their taxonomic assistance. Mol- 



lusc identifications were made by Rae Baxter, 

 ADF&G. 



Literature Cited 



Arntz, W. E. 



1974. The food of juvenile cod iGadus morhua L.) in Kiel 

 Bay. [In Germ., Engl, summ.] Ber. dtsch. wiss. Komm. 

 Meeresforsch. 23:97-120. 

 BARR, L. 



1970. Alaska's fishery resources — the shrimps. U.S. Fish 

 Wildl. Serv., Fish. Leafl. 631. 10 p. 



BEAN, T. H. 



1887. The cod fishery of Alaska. In G. B. Goode and staff 

 of associates, Fishery and fishery industries of the United 

 States, Sec. V. Vol. 1, p. 198-226. Wash. 



BROWN, R. B., AND G. C. POWELL. 



1972. Size at maturity in the male Alaskan tanner crab, 

 Chionoecetes bairdi, as determined by chela allometry, 

 reproductive tract weights, and size of precopulatory 

 males. J. Fish. Res. Board Can. 29:423-427. 



COBB, J. N. 



1916. Pacific cod fisheries. Rep. U.S. Comm. Fish., 1915, 

 append. 4, 111 p. (Doc. 830.) 



DAAN, N. 



1973. A quantitative analysis of the food intake of North 

 Sea cod, Gadus morhua. Neth. J. Sea Res. 6:479-517. 



705 



