For the central subpopulation of northern anchovies, the 

 following formula was adopted for OY; 



1. When the estimated spawning biomass is less than 

 100,000 tons, OY is 0; 



2. When the estimated spawning biomass is between 100,000 

 and 1 million tons, OY is 18,000 tons for the non-reduction 

 fishery catch; and 



3. When estimated spawning biomass is 1 million tons or 

 more, OY for the combined reduction and non-reduction fish- 

 eries is 18,000 tons or 1/3 of the biomass above 1 million tons, 

 whichever is greater. 



Because 10% of the central subpopulation is found, in the 

 U.S. FCZ, optimum yield within the FCZ was set at 707 o of the 

 OY for the central subpopulation as a whole. 



Under this formula OY at a biomass of 1.8 million tons 

 spawning biomass would be 267,000 tons, considerably less 

 than the MSY figure of 484,000 tons at the same biomass. OY 

 for a spawning biomass of 3 . 6 million tons, the estimated pop- 

 ulation for 1976, would be 870,000 tons, much greater than 

 the 1976 harvest of about 200,000 tons. 



The maximum carrying capacity of the area was estimated 

 at 3.9 million tons spawning biomass of anchovies. The average 

 spawning biomass 1951 to 1975 has been 1.95 million tons. 

 Under the proposed harvest quota, the spawning biomass would 

 average 2.55 million tons, a level greater than equilibrium 

 biomass. Spawning biomass would fluctuate around this average 

 and would be expected to fall below 1 million tons during 19% 

 of the years. 



Pre-spawning anchovies of ages and 1 will be protected 

 for the most part by closure of the 3 mile inshore area by the 

 state of California and by the 5 inch minimum size limit. These 

 young fish contribute mostly to the recreational fishery 

 as forage and live bait. 



Review : The OY formula provides for a fishery that is 

 less intense than managing for MSY, but more intense than 

 recent harvesting. 



Maintenance of an anchovy population sufficient to sustain 

 adequate predator stocks was one of the management objectives 

 of this plan. However, no apparent attempt was made to define 

 quantitatively what "adequate" levels of predators would be. 

 Determining a quantitative or operational definition of 



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