408 



Fishery Bulletin 89(3). 1991 



therefore, a change in acceptable biological catch does 

 not appear to be necessary to protect the stock. Esti- 

 mates of shortbelly rockfish abundance (and potential 

 yield) to the north and south of the surveyed area may 

 not be feasible prior to development of a fishery. How- 

 ever, the limited data available suggest that other ( 

 aggregations may exist. In a study of larval rockfish 

 distributions from Baja California to Bodega Bay, 

 California; MacGregor (1986) found that shortbelly 

 rockfish larvae were most abundant in the Ascension 

 Canyon to Farallon Islands area (49%). He also 

 detected a large concentration in the Channel Islands 

 off southern California (35%), suggesting the presence 

 of a large number of adults in that area. Gunderson 

 and Sample (1980) examined the distribution of pelagic 

 adult rockfish from southern California to Vancouver, 

 British Columbia. They found the highest concentra- 

 tion of shortbelly rockfish in the Ascension Canyon to 

 Farallon Islands area but also detected concentrations 

 in the Channel Islands, in the Point Sur area of Califor- 

 nia, and off Bodega Bay, California. A smaller concen- 

 tration was found off the Columbia River in Oregon. 

 These observations suggest that our estimates of MSY 

 are conservative when applied coastwide. More refined 

 estimates of potential yield should be possible once a 

 fishery develops or once planned larval production 

 surveys of the Ascension Canyon to Farallon Islands 

 area have been conducted. 



Acknowledgments 



We thank Thomas Laidig, Bruce Leaman, William 

 Lenarz, Milton Love, and Stephen Ralston for their 

 valuable critiques of this manuscript. 



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