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2. The effects of fishing and their compensation through the population 

 growth rate and spawning stress mortality changes vary considerably from species 

 to species, indicating among others that different species tolerate different 

 amounts of fishing without decreasing the total biomass. 



3. The numerical experiments demonstrate that some relation between spawning 

 biomass and recruitment must exist at all levels of biomass, and that this relation 

 neither decreases nor levels off at high spawning biomass. 



k. Empirical results suggest that recruitment to exploitable stock must be 

 a nonlinear function of prey density dependent predation on juveniles. These 

 relations cannot be determined with a single species approach. 



