Table If.— Pood Items In the stonacta cont«ntB 



of sockeye ealaon 



Table 5. — Food Items in the stcnacb 

 contents of chum salmon 



1/ Volume contribution In percentage 



2/ Frequency of occurrence In percental 



Food of the sockeye salmon 



A marked difference was found in the 

 amount of material in stomachs of fish 

 captured In Region A fron those captured 

 in Regions B and C. These differences were 

 also reflected in the quantitative differ- 

 ences of individual food organisms found in 

 the three regions. In Rsgions A and B 

 amphlpods fonned the major food of the 

 sockeye, and in Region C copepods and eu- 

 phausiids were of primary importance. In 

 Region A only two items, amphlpods and 

 crustacean Isirvae, contributed more than 

 10 percent to the volume of the diet. In 



Region B only amphlpods contributed more 

 than 10 percent to the volume of the diet, 

 and in Region C euphauslids, copepods, and 

 fish were found in volumes exceeding 10 

 percent. All other items were of secondary 

 Importance in tenos of volume, although the 

 f^cjiency of their occurrence may be high. 

 Pteropods and fish, for example, were found 

 in 23 and 16 percent of the stomachs from 

 Region C; however, they contributed only 

 5.0 and 11.0 percent to the total volume 

 of the diet. Amphlpods seemed to have a 

 wide geographic distribution. In Region C, 

 where they contribute only k.O percent of 

 the volume to the diet, they are found in 

 29.6 percent of the stcmachs examined. 



Food of the chum salmon 



The amount of material found In the 

 chum salmon stcmachs Increased as the area 

 of capture became more oceanic. In Region 

 A all items other than copepods and euphau- 

 slids contributed volumes in excess of 10 

 percent to the diet of the chum. The cope- 

 pods and euphauslids, which contributed 

 only 2 and 3 percent to the volinne of the 

 diet, were found In 12.5 and 25.0 percent 

 of the stomachs. In Region B each of four 

 items, euphauslids, amphlpods, fish, and 

 squid, contributed quantities In excess of 

 10 percent to the volume. The remaining 

 items, copepods, pteropods, and crustacean 

 larvae, although of secondary importance 

 volumetrically, were found frequently in 

 the stomachs. Copepods, for example, al- 

 though only contributing 5-9 percent of 

 the volume, were found in Mj-.^ percent of 

 the stomachs. In Region C four items, 

 euphauslids, copepods, pteropods, and fish, 

 each contributed quantities in excess of 

 10 percent to the volume. The remaining 

 items, although appearing frequently in the 

 stomachs, seemed to be of lesser importance 

 to the diets of fish from this region. 

 Amphlpods were found in 69.9 percent of 

 the fish, although they contributed only 

 7-8 percent of the total voluaae. 



Food of the pink salmon 



No major differences appeared in 

 volume of stomach contents of pink salmon 

 from the different areas. In Region A 

 each of four items, amphlpods, pteropods, 

 fish, and crustacean larvae, contributed 

 more than 10 percent to the volume of the 

 diet of the pink salmon. Of the four, 

 amphlpods accounted for 56.9 percent of 



