almost certainly overexploitation. The plan objective of 

 allowing a safety margin was not fulfilled in establishing 

 OYs. 



The domestic portion of this fishery is very small, on 

 the order of 400 out of 1.4 million metric tons. The esti- 

 mated physically possible maximum catch by domestic fisheries 

 was about 160,000 metric tons, or slightly over 1% of total 

 OY. There was ample room to reduce OYs, e.g., to half of MSY , 

 to allow an ecological safety margin without restricting the 

 domestic fishery. Such a reduction could have represented a 

 reasonable ecological consideration for reducing OY from MSY, 

 as provided by the definition of OY in the FCMA. 



There appears to have been no consideration of endangered 

 species or critical habitat in this fishery management plan. 

 Marine mammals were treated as a nuisance interfering with gear 

 and competing with fishery for fish resources. No apparent at- 

 tempt was made to evaluate the impact of proposed fishing 

 levels on the carrying capacity of the ecosystem for marine 

 mammals, even though there are indications that populations of 

 North Pacific fur seals have decreased in the 1970' s, in con- 

 junction with intense fishing on pollock (U.S. Department of 

 Commerce, 1979). The questions of optimum sustainable popula- 

 tions of and optimum carrying capacity for marine mammals were 

 not addressed as issues under the discussion of the MMPA. 



No estimate was made of reduction in food available to 

 predators in conjunction with fishing intensity levels asso- 

 ciated with indicated OYs , even though data for such calcula- 

 tions are available and organized in conjunction with the 

 DYNUMES model referenced in the plan. Comments by reviewers on 

 the first draft of this report indicated the implicit assump- 

 tion that the use of estimates of natural mortality rate in MSY 

 calculations automatically accounts for predator needs . That 

 assumption is not entirely valid, as discussed in Appendix G of 

 this report. The rate of natural mortality, M, (largely preda- 

 tion) may not remain constant when predators shift to alternate 

 food sources, in this case also harvested groundfish, as the 

 density of preferred prey decreases . Even if the rate M remains 

 constant, variation in the standing stock to which the rate is 

 applied (analogous to constant interest rates and varying prin- 

 cipal in a bank account) results in variation in the annual to- 

 tal biomass of prey available to predators (analogous to year- 

 ly total interest paid) . 



Estimates cited in the plan indicate that marine mammals 

 and birds consume more groundfish than the fishery removes. In 

 most fisheries, total catch represents only a small part of the 

 total annual production of the stock. It does not follow that 

 the fishery has no impact on the stock or its predators. In 

 the absence of a fishery, all of the production of a particular 



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