Woodbury and Ralston Growth rates and birthdate distributions of Sebastes spp. off central California 



527 



Bocaccio The data presented in Figure 

 4 show the relationship between standard 

 length and age for the aged subsamples 

 of pelagic juvenile bocaccio in each year 

 during 1984-88. No data were available 

 for 1983. There is some suggestion of cur- 

 vilinearity in the data, especially in the 

 youngest stages of growth, but this can- 

 not be confirmed due to annual differ- 

 ences in the age domain sampled. For ex- 

 ample, specimens ranged in age from 35 

 to 113 days during 1986, whereas in 1985 

 they ranged from 84 to 131 days. Thus, 

 differences in slope between these years 

 may be due to a year effect in the linear 

 model, or to violation of the linearity 

 assumption. In spite of the suggestion of 

 nonlinearity in the data when pooled over 

 years, the linear model was used to con- 

 form with the analyses performed on the 

 other four species studied and because it 

 fits well on a year-by-year basis. 



A simple linear growth model was fit 

 to individual years (Table 2). During the 

 period studied, the highest growth rate 



87 



Shortbelly 85 86 



88 84 



83 



0.55 



0.65 



Bocaccio 86 



84 87 



0.50 0.60 0.70 0.80 0.90 1.00 



Chilipepper 



86 

 85 



B8 



87 



Widow 86 



8B 

 85 



0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 



Yellowtail 85 



87 



0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 



Slope (mm/d) 



Figure 3 



Results of all possible pairwise least-significant-difference tests 

 of annual differences in growth rate (slope) for each species 

 studied. A bar over and connecting different years (1983-88) 

 indicates lack of significance. No adjustments were made to 

 control the experiment-wide probability of Type I error. 



