304 



Fishery Bulletin 97(2), 1999 



35 4 45 



Standard length at hatching (mm) 



Figure 8 



Relation between larval size and otolith size at hatching reported in the literature for different popula- 

 tions of cod. Shown for each data point are means and bivariate standard deviations (when available). The 

 sources for individual data points are shown as letter codes above the abscissa. Codes: (Al Radtke ( 1984); 

 (Bl Bergstad (1984); (C) Radtke il989l; (D) Geffen (1995); (E) 1991-92 cohort from Meekan and Fortier 

 (19961; (F) 1992-93 cohort from Meekan and Fortier (1996); and (G) this study. Estimates of SL at hatch- 

 ing for Meekan and Fortier were taken from estimates of mean hatching size for each cohort given by 

 Miller et al. (1995). 



Atlantic herring), individual variability in the inter- 

 cept may be significant. We recommend that, at a 

 minimum, stock specific values for intercepts be used 

 if the interest is in periods of the life history shortly 

 after hatching. Further, caution should be exercised 

 in relating shifts in the back-calculated distribution 

 of radii at hatching to size-selective mortality. More 

 careful study of the relationship between otolith size 

 and fish size in individual species is likely warranted 

 if researchers wish to employ otolith-based back cal- 

 culation (Chambers and Miller, 1995). 



and the crew of the RV Petrel V for their help. Fund- 

 ing for this research was provided by OPEN (the 

 Ocean Production Enhancement Network), one of 15 

 Centres of Excellence supported by the Government 

 of Canada, through the Natural Sciences and Engi- 

 neering Research Council (NSERC) of Canada, and 

 by an NSERC Strategic research grant to WCL. TJM 

 was supported in part by the U.S. National Science 

 Foundation under grant no. OCE-9728750. 



Literature cited 



Acknowledgments 



We thank Francois Landry, Rob Douglas, and Patricia 

 Avendano for help in videotaping cod eggs and newly 

 hatched larvae at sea. The cruises that provided these 

 data could not have been conducted without the as- 

 sistance of a team of colleagues from Dalhousie and 

 Laval Universities. We thank Capt. Wayne Walters 



Bergstad, O. A. 



1984. A relationship between the number of growth incre- 

 ments on the otoliths and age of larval and juvenile cod, 

 Gadus morhua L. Flodevigen Rapportser 1:251-272. 

 Brander, K. 



1994. Patterns of distribution, spawning, and growth in 

 North Atlantic cod: the utility of inter-regional compari- 

 sons. ICES Mar Sci. Synip. 198:406-413. 

 Bolz, G. R., and R. G. Lough. 



198.3. (Irowth of larval Atlantic cod, Gadus morhua. and 



