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Fishery Bulletin 88(3). 1990 



are independent class variables (SAS Institute 1985). 

 A is the acclimation and spawning temperature (Tsp); 

 B is the embryo and larval incubation temperature 

 (Tine); C is the block effect or individual female tag 

 number (Block). This maternal factor is nested within 

 the acclimation temperature and represents the vari- 

 ability among individual spawning females. This fac- 

 tor was added to the model to block out fish-to-fish 

 variability. It was significant for all dependent vari- 

 ables tested (Table 5). A *B is the interaction of acclima- 

 tion and incubation temperatures. 



Significant interactions between spawning and in- 

 cubation temperature were observed at hatch for 

 length and DNA content, and at first feeding for 

 length, RNA, and protein content. In these cases, 

 where the effects of spawning temperature and incuba- 

 tion temperature were nonadditive, simple main effects 

 were tested at each spawning and incubation tempera- 

 ture using Tukey's studentized range test. Where no 

 temperature interaction was observed (yolk volume, 

 RNA, and protein content at hatch, and DNA content 

 at first feeding) main-effects means were calculated 

 and differences among main-effects means were tested 

 for significance using Tukey's studentized range test. 



At hatching, standard length showed a significant 

 temperature interaction (Table 5). At a spawning 



temperature of 2°C, standard length decreased with 

 increasing incubation temperature (Table 3). At a 

 spawning temperature of 7°C, standard length was 

 higher at an incubation temperature of 7°C than at 

 4°C. Yolk volume showed no significant temperature 

 interaction, was unaffected by spawning temperature, 

 and was highest at the lowest incubation temperature 

 of 4°C. RNA content at hatch showed no significant 

 temperature interaction and decreased with both in- 

 creasing spawning and incubation temperature. DNA 

 content at hatch showed a significant temperature in- 

 teraction. At a spawning temperature of 2°C, DNA 

 content was lowest at the intermediate incubation 

 temperature (7°C). At a spawning temperature of 7°C, 

 DNA content was highest at this intermediate incuba- 

 tion temperature. Protein content at hatch showed no 

 temperature interaction and was unaffected by either 

 spawning or incubation temperature. 



At first feeding, standard length showed a signifi- 

 cant temperature interaction. At both spawning tem- 

 peratures (2° and 7°C) standard length decreased with 

 increasing incubation temperature (Table 4). RNA con- 

 tent at first feeding showed a significant temperature 

 interaction. At a spawning temperature of 2°C, RNA 

 content was lowest at the highest incubation tempera- 

 ture (10°C). At a spawning temperature of 7°C, RNA 



