FISHERY BILLETIN: VOL. 88. NO. 4 



Table 4.— Mean measurements (mm) for six morphometric characters for cfium salmon 

 sampled during 1984. Measurements for each individual were standardized to a postorbital- 

 hypural length of 520 mm. Standard deviations are indicated in parentheses The size 

 (%) of each standardized character relative to body length is indicated for both Yukon 

 and British Columbia chum salmon. Data for 4,862 male and 4,044 female British Colum- 

 bia chum salmon were standardized to 600 mm postorbital-hypural length and were derived 

 from Beacham and Murray (1987). 



British Columbia (Beacham and Murray 1987). 



Survival Rates 



Embryo survival rates were lowest at a 4°C incu- 

 bation temperature and highest at 12 °C, with sig- 

 nificant differences observed among incubation 

 temperatures {P < 0.05) (Table 5). Significant dif- 

 ferences were also observed in embryo survival rates 

 among families (P < 0.0), but not between replicates 

 within families (P > 0.10). An interaction between 

 family and incubation temperature occurred (P < 

 0.01), illustrating that trends in embryo survival 

 with respect to incubation temperature were not the 

 same for all families. 



Alevin survival rates were uniformly high (Table 

 5), with no significant difference observed among 

 temperatures, among families, or between replicates 

 within families. The interaction between family and 

 incubation temperature also occurred for alevin sur- 

 vival rates (P < 0.05). 



Table 5. — Survival rates of embryos and alevins for Kluane River 

 chum salmon maintained at constant water temperatures of 4°, 

 8°, and 12°C. Time of 50% hatching (days) of the alevins and 50% 

 emergence (days) of the fry is also indicated. N is number of fer- 

 tilized eggs (for embryo survival rates) or alevins hatched (for alevin 

 survival rates). Standard deviations of 50% hatching and emer- 

 gence times are in parentheses. 



December or early January (Beacham and Murray 

 1986, 1987), nearly three months later than the 

 spawning time of the Kluane River population. 



Hatching and Emergence Time 



Warmer water temperatures during incubation 

 enhanced the development rate of Kluane River 

 chum salmon (Table 5). Timings of both alevin hatch- 

 ing and fry emergence at a specific incubation tem- 

 perature were comparable with that of a British 

 Columbia chum salmon population spawning in late 



Alevin and Fry Size 



Alevin and fry length and weight were influenced 

 by the water temperature during development. The 

 longest and heaviest alevins and fry were observed 

 at 4°C (Table 6). Significant differences in alevin 

 length and weight were observed among incubation 

 temperatures, among families, and between reph- 



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