Quinonez-Velazquez: Age validation and growth of Melanogrammus aeglefinus and Pollachius virens 



311 



tured. Haddock larvae and juveniles («=602) ranged 

 from 2.7 to 83.0 mm in SL and from to 128 d in age, 

 and pollock larvae and juveniles (n=519) from 2.8 to 

 23.8 mm in SL and from to 84 d in age. For each 

 year, Gompertz growth curves were fitted to describe 

 the mean growth of larval and juvenile haddock 

 (1991, 1992, and 1993) and pollock (1992 and 1993) 

 (Fig. 6; Table 5). Length at hatching predicted from 

 the curves was 4.1 mm for haddock and 4.5 mm for 

 pollock, both within the range reported by previous 

 studies (Fridgeirsson, 1978; Bolz and Lough, 1983; 

 Fahay, 1983). Because the predicted inflection point 

 for both haddock and pollock curves fell beyond the 

 length range analyzed, the end of the first growing 

 season had not been reached. 



Although haddock larvae older than 80 d were ob- 

 tained in 1991 and 1992, they were not used in the 

 comparison of growth. Haddock growth rates (mm/d) 

 during the first 80-d period in 1993 were different 

 from those in 1991, and growth rates in 1993 were 

 different from those in 1992 (ANCOVA, P<0.01) 

 (Table 6 ). The 1993 cohort had the lowest growth rate. 

 The 1991 and 1992 cohorts had similar growth rates 

 (ANCOVA, P=:0.84). The average growth rate of lar- 

 vae was 0.21 mm/d during the first month and 0.42 

 ~mm/d during the second month. Growth continued 

 exponentially from the predicted length at hatching 



throughout the size range of larvae and juvenile col- 

 lected, there being no indication of a cessation in growth. 

 Pollock growth rates (mm/d) varied significantly 

 among years (ANCOVA, P<0.01 ) (Table 6). However, 



