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the fulfillment of the conservation principle of the Treaty. With fixed harvest ceilings, 

 the numbers of fish which are harvested do not vary from year to year, even when fish 

 abundance declines and lower harvests are warranted. In addition, fixed harvest 

 ceilings do not allow for increased harvest opportunities when run sizes increase; 

 consequently, they reduce incentives for stock rebuilding efforts. 



* There is an obvious need to replace fixed harvest ceilings with abundance-based 

 Total Allowable Catch (lAC) levels that would be responsive to annual variations 

 in run sizes as well as to longer-term changes in freshwater and marine survival 

 rates. 



* TACs should be based on the harvestable surplus remaining after a sufficient 

 number of fish is allowed to escape the fishery to sustain salmon populations, 

 rebuild weak stocks, maintain genetic diversity, and allow salmon to fulfill their 

 ecological roles (i.e., a spawner escapement goal). TACs for strong stocks may be 

 based on maximum sustainable yield (MSY); however, TACs for weak stocks 

 should be based on a rebuilding schedule which, for example, might have as a 

 goal the maximization of recruit numbers rather than MSY. The TAC is the 

 difference between the actual projected (prior to the start of the season) 

 abundance and the escapement goal. 



Methods for projecting the abundance of specific salmon populations and for setting 

 conservation-based spawner escapement goals will be necessary to develop abundance- 

 based TACs for the populations covered by the PST. The U.S. Pacific Fishery 

 Management Council has developed such techniques, but several aspects must be 

 improved: 1) escapement goals should maximize recruitment for depleted salmon 

 populations, rather than maximize sustainable yield; 2) escapement goals should be 

 increased by a 10% "safety factor" to account for scientific uncertainty, natural 

 (unpredictable) variability, and unknown effects of harvest on the genetics of salmon 

 and on the ecosystems which salmon are a part of; 3) more accurate assessments of 

 spawner abundance are needed to prevent overfishing; and 4) better models for 

 projecting abundance are needed, particularly when salmon populations are at low 

 levels (for further information, see Chan and Fujita, 1994a). 



* Percentage allocations under such TACs, allocated according to a negotiated 

 initial allocation formula, would reduce the need for annual negotiations to 

 establish allocations. Trading, sales, or leases of quota shares could reduce 

 conflict by allowing the parties to obtain the harvest rights they need to prosecute 

 their fisheries when the distribution of salmon changes. 



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