3, 4, 5 years old 



Males 



ALASKA PENINSULA 

 1951- 57 



UJ 



g5.o^ 



U) 



a. 



y^'^rr.^r^rT 



KODIAK ISLAND 

 1948-51; 1955 



5.0- 



PRINCE WILLIAM SOUND 

 1952- 58 



500 



600 700 500 



FORK LENGTH (MM.) 



600 



700 



Figure 2. --Age -length relationships of 3-, 4-. and 5-year-old duun salmon in the Alaska Peninsula, Kodiak Island, 



and Prince William Sound areas of Alaska. 



Intraseasonal Variation 



To compare the runs of the Alaska Penin- 

 sula, Kodiak Island, and Prince William Sound 

 areas intraseasonally, fishing seasons were 

 divided arbitrarily into three periods — before 

 July 1, between July I and 15, and after 

 July 15. 



In the division by time, we assumed that 

 fish caught before July 1 on the Alaska 

 Peninsula (except those taken at Chignlk) 

 were bound for areas other than the Peninsula. 

 Chum salmon are captured simultaneously 

 with pink and red salmon in the Peninsula 

 fishery during June. Tagging experiments 

 (Gilbert and Rich, 1927; Thorsteinson, 1959) 



showed that red and pink salmon taken at 

 that time of the season were bound for other 

 areas. Since it is possible that early chum 

 salmon are also bound for other areas, we 

 felt that the data for the three periods should 

 be kept separate. 



Length. --The mean lengths and standard 

 deviations of combined yearly samples of age 

 class 4 from each area are shown by the 

 three time periods in table 3. To avoid bias 

 in years when runs of exceptionally large or 

 exceptionally small fish were not sampled in 

 all time periods, the data are combined for 

 only those years when three periods were 

 represented in the Alaska Peninsula area 

 and two in the Kodiak Island and Prince 

 William Sound areas. 



