SUMMARY 



Data on length, age, and sex ratio of chum 

 salmon were collected between 1948 and 1958 

 in the Alaska Peninsula, Kodiak Island, and 

 Prince William Sound areas of Alaska. The 

 data are not complete or continuous, as no 

 formal program for sampling was organized. 

 Material was collected according to the time 

 available to biologists working in the areas 

 and the availability of the fish. The data are 

 the only biological information (except for catch 

 statistics) for past runs of this species in the 

 three areas, and as such represent an important 

 source of historical and reference material. 

 They are therefore included as an appendix 

 to this report. 



Analyses were performed by grouping the 

 data by years, by area, and by time periods 

 within years. The data permit only general 

 statements concerning the chum salmon runs 

 to three areas, but do provide a measure of 

 the Intraseasonal and interarea variability in 

 length, age, and sex ratio. 



Kodiak Island has significantly more 5-year- 

 old fish and fewer 3-year-old fish than the 

 other two areas. 



5. Age composition of the runs changes 

 within seasons in all three areas. As the 

 season progresses, 3-year-olds increase and 

 5-year-olds decrease. The percentage of fish 

 in age class 4 remains fairly constant through- 

 out the season. 



6, Sex ratios do not deviate markedly from 

 50:50, either by area or in time. The trend is 

 toward fewer males as the season progresses. 



ACKNOWLEDGMENTS 



Several members of the Fisheries Research 

 Institute staff contributed to the work reported 

 here. The principal contributors were John F. 

 Rocs, who conducted some of the sampling 

 and read some of the scales from the Alaska 

 Peninsula area, and Charles E. Walker, who 

 collected data and read scales from the 

 Kodiak Island area. 



The analyses are summarized as follows; 



1. Length distributions of chum salmon in 

 the three principal age classes overlapped 

 considerably. Three- and five-year-old length 

 distributions overlapped by 50 percent, and 

 age class 4 overlapped almost the entire range 

 of the adjoining two age classes. Consequently, 

 length is not a useful guide to age in these 

 areas, and vice versa. 



2. Little difference was found in the mean 

 size of chum salmon of the same age class 

 either among the three areas or during the 

 spawning season. Prince William Sound fish 

 were largest. Mean lengths increased from 

 west to east. 



3. Age class structure of the chum salmon 

 runs of the central and western regions of 

 Alaska averaged about 10 percent 3-year-olds, 

 75 percent 4-year-olds, and 15 percent 5-year- 

 olds. 



4. Age composition is similar in the Alaska 

 Peninsula and Prince William Sound areas, but 

 somewhat different in the Kodiak Island area. 



Salmon packers who assisted in the three 

 areas were: 



Alaska Peninsula area; 

 P. E. Harris Co., Inc. 

 Pacific American Fisheries, Inc. 

 Alaska Pacific Salmon Co. 

 Alaska Packers Association 

 Chignik Fisheries Co. 



Kodiak Island area: 



Alaska Packers Association 



San Juan Fishing and Packing Co. 



Kodiak Fisheries Co. 



Pacific American Fisheries, Inc. 



Parks Canning Co. 



Libby, McNeill and Libby 



Washington Fish and Oyster Co. 



West Point Canning Co. 



Halferty Canneries, Inc. 



King Crab, Inc. 



Prince William Sound area: 

 Halferty Canneries, Inc. 

 New England Fish Co. 

 San Juan Fishing and Packing Co. 

 Copper River Co-op, Inc. 



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