BOEHLERT: AGE DETERMINATION IN FISHES 



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 FORK LENGTH (cm) 



Figure 6. — Comparisons of mean otolith section ages at length 

 from the confirmation subsample of Sebastes diploproa. 

 Triangles represent otolith section age and circles the model 

 estimated section age. 



Figure 7. — Locations of 1980 West Coast Survey collections 

 from which otoliths of Sebastes pinniger were taken for the 

 current study. Samples from the FV Pat San Marie and the FV 

 Mary Lou are included. 



Table 8. — Summary of biological and otolith data from the subsampled groups of Sebastes pinniger 



used in developing the age models. 



Females (A/ = 121) 



Males (N = 171) 



Variable 



Minimum Maximum Mean 



SD 



Minimum Maximum 



Mean 



SD 



Depth of capture (fathoms) 32 100 69.8 12.66 37 103 73.3 14.39 



Fork length (mm) 152 610 497.8 69.25 170 579 481.64 64.20 



Otolith length (mm) 8.00 23.40 19.62 2.27 8.59 22.89 19.56 2.31 



Otolith width (mm) 4.45 12.02 9.60 1.06 4.69 11.07 9.46 1.01 



Otolith thickness (mm) 0.83 2.01 1.54 0.19 0.79 2.41 1.64 0.29 



Otolith dry weight (mg) 53 821 486.7 135.5 58 867 517.0 160.69 



Whole otolith age (yr) 2 19 12.4 3.16 2 25 13.2 3.79 



Otolith section age (yr) 2 33 14.83 5.09 2 54 20.02 9.77 



extent seen for S. diploproa. Otolith weight is 

 again an exponential function of length, particu- 

 larly for males. For females, however, this rela- 

 tionship was nearly linear. Of the ages determined 

 in the calibration subsample, otolith weight has 

 the strongest linear association with whole otolith 



age for females and whole otolith age and section 

 age for males (Table 9). 



The multiple regression models constructed to 

 predict whole otolith age were based upon fewer 

 variables than for S. diploproa , but included vari- 

 ables were highly significant (Table 10). The coeffi- 



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