384 



Fishery Bulletin 98(2) 



10 



East of Anticosti Island 



All genotypes 



West of Anticosti Island 



Mean = 8.24 

 S.E. = 0.09 



MDH*A1A1 



Mean = 9.20 

 S.E. = 0.11 



MDH*AIA2 



il U |lift|iiiqw^W^^Pp^n 



Mean = 9.15 

 S.E. = 0.12 



p h [ iiii[i 



Mean = 9.14 

 S.E. = 0.17 



iiii|iii n iiii 



f*^ 



A 



MDH* A2A2 



Mean = 7.64 

 S.E. = 0.12 



4.0 60 SO 10,0 i:,0 14.0 





Hm i|'iii|iiii[i 



Mean = 7.13 

 S.E. = 0.07 



^i[ H i H ltl H II M |llll|l 



4.0 b,0 80 10.0 120 14.0 



Standard length (mm) 



Figure 5 



Distribution of standard lengths of redfish larvae analyzed for MDH variation in 

 1991 by eastern and we.stern sectors of the Gulf of St. Lawrence and by genotypes. 



explained by introgressive hybridization between S. 

 faaciatus and S. mentella in the Gulf. Our results do 

 not rule out this possibility. Hybridization between 

 S. fasciatus and S. mentella was also suggested 

 as one possibility to explain the RFLP patterns of 

 rDNA observed in adult redfish from the Gulf of 

 St. Lawrence (Desrosiers et al., 1999), where indi- 

 viduals with the rDNA hybrid type had more affi- 



nities with S. mentella than with S. fasciatus. In 

 fact, hybridization between Sehastes species may not 

 be an uncommon phenomenon because introgression 

 was recently observed between three rockfish species 

 in Puget Sound (Seeb, 1998). In our study, the simi- 

 lar size distribution of larvae of the MDW'AIAI and 

 MDH''A1A2 genotypes suggests that heterozygous 

 individuals have more affinity with the S. mentella 



