NOTE Fargo and Tyler: Oocyte maturation in Pleuronectes vetulus 



197 



spawners spawn at a different time than the rest of 

 the stock. We can suggest no mechanism to account 

 for this and more data are required to corroborate 

 these results. 



There is also evidence of interannual variability 

 in oocyte maturation and this process appears to be 

 size-related. Smaller fish matured later and 

 spawned later than larger fish. Our results indicate 

 that the time of peak spawning and the duration of 

 the spawning season are variable from year to year. 

 The results from this study provide baseline infor- 

 mation for an investigation of the recruitment biol- 

 ogy of this stock. 



Acknowledgments 



We wish to acknowledge John Bagshaw, Serge 

 Villeneuve, Tammy Laberge, Christina Horvath, 

 Tracy Sexton, and Corinne Kikegawa for their aid 

 in preparing the slides for histological examinations 

 and photography of specimens. Ron Tanasichuk and 

 Doug Hay reviewed the manuscript and provided 

 advice regarding the spawning characteristics for 

 the species. The scientific editor and three anony- 

 mous reviewers provided a number of suggestions 

 which improved the paper. 



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