stocks which had not been gathered together prior to the 

 negotiation of the treaty, and they constitute a significant 

 advance in the science of fishery conservation. This has 

 been presented to the Commission in the form of seven 

 major technical docxaments and about twenty other supporting 

 documents, which have been our cases for abstention to date. 

 Without a doubt, additional documents will be required, for 

 while our cases for abstention are for all reasonable pur- 

 poses conclusive, they are not, and never can be expected to 

 be, entirely perfect. 



For salmon, we have presented evidence which shows 

 that, for several years following World War II, a greatly 

 intensified United States fishery failed to provide an increase 

 in yield. We have also shown, for most of ournnajor red {0. 

 nerka) and pink {0. gorbuscha) salmon-producing areas, that 

 recent spawning escapements have been lower than those 

 escapements associated with the larger average yields. We 

 have concluded from this that more intensive fishing woiold 

 further reduce escapements and probably would result in a 

 decrease, not an increase, in the sustained yield. Indeed, 

 with regard to Bristol Bay red salmon, which Canada ab- 

 stains from fishing, the Canadian Section agreed with this 

 conclusion at the last annual meeting of the Commission, 



However, the Japanese Section of the Commission has 

 stated that we have not yet demonstrated that more intensive 

 exploitation of our salmon stocks would not provide a sub- 

 stantial increase in yield which covild be sustained. Their 

 scientific argiunents have been based on the hypothesis that 

 the long-term average yield from a salmon stock is pri- 

 marily controlled by natural factors, and that fishing plays 

 a relatively minor role. This problem of separating the 

 effects of a fishery from those of the environment is a diffi- 

 cult one, and it will be necessary to examine the logic of 

 Japanese scientific argximents regarding the effects of fish- 

 ing on salmon stocks and to demonstrate, with supporting 

 data, the weaknesses of their logic. In addition, it is im- 

 portant that we gather the scientific evidence required to 

 determine whether or not a high-seas salmon fishery results 

 in a waste of the salmon resources. 



For North American halibut stocks, we have presented 

 one document on the history of the changes in the stock and 

 the fishery, and another on the yield to be expected at various 

 levels of fishing intensity under present-day conditions of 

 growth and natural mortality. This latter docvunent is a 

 significant contribution to our knowledge of the halibut stocks. 

 The scientific data indicate, for halibut stocks outside the 

 Bering Sea, that present-day fishery is taking almost the 

 maximum yield from the stocks, and that greatly intensified 

 fishing would provide only a relatively small increase in 

 yield, Canadian scientific reports on halibut have reached 

 essentially the same conclusions, 



Japan has stated that we have not yet demonstrated that 

 more intensive fishing of the halibut stocks would not provide 

 a substantial increase in yield which could be sustained, 



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