FISHERY BULLETIN: VOL. 74, NO. 4 



Table 3.-Pooled means and variances of means for lengths, weights, and development 

 index, AT,,, of pink salmon fry (50 fry /sample) at Auke Creek in spring of 1973. 



Source 



Creek 

 Incubator: 



A 



B 



C 



D 



Number of 

 samples 



Length (mm) 

 Mean Variance 



Weight (mg) 

 Mean Variance 



/<P index 



Mean 



13 



8 

 8 

 4 

 5 



32.45 



31.57 

 32.17 

 32.21 

 32.29 



0.00272 



0.00252 

 0.00276 

 0.00412 

 0.00483 



260.2 



1.630 



260.0 1.917 



269 9 1.856 



273.2 3.352 



268.6 2.714 



1.964 



2.008 

 2.009 

 2.012 

 1.987 



Variance 



5.36 X 10-4 



5.50 X 10-4 



5.54 X 10-4 



9.61 X 10-4 



9.92 X 10-4 



CREEK 



INCUBATOR A 

 INCUBATOR B 

 INCUBATOR C 

 INCUBATOR D 



Figure 6. -Weighted means and 95% 

 confidence intervals of these means of 

 indices of development, Kd, of preserved 

 fry from Auke Creek and four gravel 

 incubators. 



and fry from incubator D had an average length of 

 32.29 mm, which was not significantly different 

 from the average length for creek fry-32.45 mm. 

 Indices of development were higher for fry from 

 all the gravel incubators than for creek fry (Figure 

 6). The mean indices of development for gravel 

 incubator fry ranged from 1.987 to 2.012, whereas 

 the mean for creek fry was only 1.964 (Table 3). In 

 an earlier test (Bailey and Taylor 1974) the aver- 

 age Kp index decreased about 0.005 unit/day in 

 the final stages of alevin development. Since the 

 average /Q> index for incubator fry was 0.016 unit 

 higher than the index for creek fry, incubator fry 

 apparently emerged about 3 days earlier in their 

 development. 



Time of Emergence and Seaward Migration 



Fry of the 1972 brood from the gravel incubators 

 migrated voluntarily between 15 March and 23 

 May 1973; the median date was 14 April (Figure 7). 

 Creek fry emigrated between 16 March and 15 

 May; the median date was 27 April (Figure 7). 



Size of Returning Adults 



Length measurements of adults from the 1972 

 brood that returned to the weir in 1974 are 

 classified by sex, origin (whether creek or hatch- 

 ery), and time of return (either early or late run). 

 Mean lengths and sample sizes (Table 4) were used 

 as basic observations with which to perform an 

 analysis of variance (Scheffe 1959: 362-363) to 

 search for differences in size among the clas- 



100 



90 



z 

 o 



I 80 



< 



H 

 O 

 \- 60 



O SO 



< 



t- 

 z 



LU 



O 40 



> 



I- 



5 



D 

 U 



30 



20 



HATCHERY FRY 



CREEK FRY 



/ I I I jj , MIDDATE OF 



EMERGENCE 



15 20 25 

 MARCH 



T — I — I — I — I — I — I — I — I — I — r- 



5 10 IS 20 2S ' 5 10 IS 20 2S 30 



APRIL 



MAY 



Figure 7.-Daily cumulative percentage of pink salmon fry 

 migrations of creek fry and hatchery fry from Auke Creek in 

 1973; solid lines represent fin-marked fry and dashed lines 

 represent total fry in the respective migrations. 



sifications. Analyses were performed separately 

 for each sex because underlying variances of 

 hatchery fish differed significantly between sexes. 

 Spawning males typically vary more in length 

 than spawning females. The corresponding tests 

 for creek fish did not indicate inequality of vari- 



968 



