Gunderson: Spatial patterns in the dynamics of slope rockfish stocks 
229 
tempted to eliminate directed fishing on Pacific ocean 
perch in the U.S. Vancouver-Columbia management 
area, fishermen have been observed fishing for this 
species in the northern Washington index areas, 
where Pacific ocean perch and other rockfish are the 
most abundant fish in catches (Fig. 2). Only distance 
and time act as disincentives for fishermen, who have 
yet to achieve their “incidental” allotment of Pacific 
ocean perch, from moving to areas such as these to 
“top off’ their catch. It is not surprising then that 
stocks in the index area have failed to rebuild as the 
Council had hoped. While often ignored in manage- 
ment considerations owing to a lack of information, 
other species in the slope rockfish assemblage (nota- 
bly rougheye and splitnose rockfish) have probably 
experienced the same pattern of overfishing as Pa- 
cific ocean perch and should be considered when con- 
templating future rebuilding plans. 
One possible solution to many of the problems that 
currently exist in managing slope rockfish stocks is 
to delineate areas such as the index sites, where rock- 
fish dominate the exploitable fish biomass (Fig. 2), 
and to eliminate all fishing within them. A variety of 
questions remain as to the optimal size and spatial 
dispersion of such closed areas (or “refugia”), as well 
as the enforcement problems associated with main- 
taining them, but it seems clear that if managers 
cannot rebuild rockfish stocks in areas of prime habi- 
tat, it is unlikely that they will be able to rebuild 
them over broader scales. 
Acknowledgments 
This research was supported in part by grants from 
the U.S. National Marine Fisheries Service and 
Washington Sea Grant. Assistance by the scientists 
and staff at the NMFS Alaska Fisheries Science Cen- 
ter in constructing the trawl gear, implementing the 
1992 survey, and ageing the otoliths collected is grate- 
fully acknowledged. I also thank Dan Ito and Bruce 
Leaman for their comments on an earlier draft of 
this paper. 
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