dity between coastal and inshore stocks of Pacific 

 hake at this time Ermakov et al. (1974) excluded 

 oocytes <100 pirn diameter, thus excluding a large 

 fraction of unyolked oocytes constituting the reserve 

 fund. Their estimates of total fecundity (compar- 

 able fork length) are one-half to one-third of those 

 reported here for hake in the Strait of Georgia 

 (>40 mm) and are also lower than the present 

 estimates for apparent fecundity (oocytes ^200 ^m 

 diameter). 



MacGregor (1966, 1971) counted advanced, yolked 

 oocytes (>600 /urn) only, premised on his assumption 

 that only these cells were destined for release On 

 the basis of relative fecundity (eggs per gram), for 

 yolked oocytes >580 fim diameter of comparable size 

 to MacGregor's "large, yolked" or "advanced" 

 oocytes, the female Pacific hake in the Strait of 

 Georgia are considerably less fecund (54-164 eggs/g) 

 over the fork length range of 40-80 cm than are Baja 

 California hake which averaged 216 eggs/g (MacGre- 

 gor 1971). However, the lack of distributional bi- 

 modality in the Canadian ovaries renders such a com- 

 parison unrealistic, for a common size threshold for 

 resorption, even if appropriate, cannot be applied 

 conveniently to individual ovaries. 



We can state with reasonable certainty that re- 

 sorption of yolked oocytes is a common occurrence 

 in both coastal and inshore stocks of Pacific hake, 

 as has been found in other forms of Merluccius 

 (Hickling 1930; Christiansen 1971). The influence of 

 ovarian resorption on annual fecundity of stock and 

 on the magnitude of released egg production from 

 individual females remains unknown. It follows that 

 the application of existing fecundity information to 

 problems of assessing magnitude of Pacific hake 

 spawning stock from released egg production, as 

 determined through ichthyoplankton surveys, should 

 reflect these reservations. 



For the Pacific hake stock in the Strait of Georgia, 

 British Columbia, resorption may not involve more 

 than 5-10% of the apparent fecundity. Hence spawn- 

 ing biomass estimates based on released egg pro- 

 duction and the apparent fecundity could be 

 rendered conservative by the observed extent of 

 resorption in this stock. 



Acknowledgments 



Staff of the Groundfish Program at Nanaimo are 

 thanked for collecting biological materials and 

 related statistics at sea, and for aging the female 

 Pacific hake used in the study (Aging Unit). Par- 

 ticular appreciation is extended to Susan Johnston 

 for her able assistance in the laboratory and to R. 



Foucher for helpful discussion and comments on the 

 original draft. 



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