56 



Fishery Bulletin 101(1) 



size-structure in this area is smaller than the equilibrium 

 size-structure obtained by fishing at F^^^, then fishing 

 the next year at a level somewhat below i^M^x will improve 

 long term yield-per-recruit. Similarly, if an area has been 

 fished below F^^j^, so that its size structure is larger than 

 what would occur when fishing at a constant rate of Fj^j^^^, 

 then it may be optimal to temporarily fish at a level higher 

 than F,^^. 



In summary, rotational fishing can improve yield- and 

 biomass-per-recruit for long-lived sedentary stocks such 

 as sea scallops. Rotational management can be part of a 

 precautionary strategy because it can help alleviate the 

 effects of growth and recruitment overfishing. Rotational 

 management will however require a rethinking of conven- 

 tional yield-per-recruit reference points. 



Acknowledgments 



I would like to thank T. Kenchington for discussions 

 regarding the equivalence of long-term survivorship 

 under rotational and constant fishing. This paper also 

 benefitted from discussions with and comments from P. 

 Rago, L. Jacobson, S. Murawski, F. Serchuk, A. Applegate, 

 and the reviewers. 



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