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Fishery Bulletin 99(1) 
Figure 3 
Three sizes of marine refugia are designed and the radius of the basic circle is 10 
km. SSR = small-size refugia; MSR = middle-size refugia, and LSR = large-size 
refugia. 
the current actual level of ABC (which includes discards), 
reduced by average discards, will be applied to future rec- 
ommended ABC under refuge management. That is, rec- 
ommended ABC in the harvestable areas will be the rec- 
ommended ABC under current management multiplied 
by (1.0 - discard rate), assuming that this average discard 
rate is constant throughout the future projection years. 
This reduced ABC does not affect the fishing industry’s 
actual harvest level if they can keep all the catch until 
ABC is attained. 
Considering that they are a very large and valuable spe- 
cies, discards of shortraker and rougheye rockfish are as- 
sumed to result primarily from season limits, rather than 
size limits. Skippers consistently develop their area-spe- 
cific skills to maximize total income, and high catch rates 
can result in a short fishing season (Hilborn, 1985). Be- 
cause harvest refugia in our study were established in 
high catch-rate zones, or preference zones for shortraker 
and rougheye rockfish, the harvesting period was assumed 
to be sufficiently prolonged where shortraker and rough- 
eye rockfish were less dense and regulatory-induced dis- 
cards would be virtually eliminated as a result. 
Model description 
A stock reduction analysis model (Kimura et al., 1984 } with 
one-parameter-based Beverton and Holt stock-recruit- 
ment relationship (Kimura, 1988) was applied for the stock 
assessment and future projections. Both analyses were 
combined to estimate the following relevant parameters: 
