. . . Pacific Coast Groundfish Fisheries 



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other Flatfish 



Important flatfishes, other than Dover sole, 

 are English and petrale soles and 

 arrowtooth flounder. English and petrale 

 soles have long histories of stable harvests, 



but they were last assessed in the mid- 

 1980's. The arrowtooth flounder fishery 

 has recently expanded in part of its range, 

 and more research on them is needed. 



Thornyhead 



Thornyheads are harvested in deep water extremely long life of shortspine 



with sablefish and Dover sole. Their catch 

 nearly tripled from 1987 to 1990 owing to 

 increased demand. Data are not yet avail- 

 able for a full stock assessment, but the 



thornyheads indicates that their harvest 

 rate must remain lower than sablefish and 

 Dover sole. 



Rockfish 



Rockfishes are also hard to assess. The 

 age of the six major species caught has 

 been well monitored, but more and better 

 data are needed for accurate stock assess- 



ment. Better survey methods must be de- 

 veloped. Assessment of the 50-plus lesser 

 rockfish species will be an even bigger, but 

 necessary, task. 



ISSUES 



Surveys 



Most needed are quantitative surveys to 

 verify the assessments of fish stocks. 

 These should include expansion of trawl 



surveys, calibration of catch rates, and de- 

 velopment of alternate survey methods. 



catch Statistics 



All groundfish catches must be monitored 

 accurately. The PacFIN program monitors 

 only groundfish landings and the biological 

 characteristics of some species. Expan- 

 sion of this program would provide full 

 biological monitoring for most species and 

 an estimate of the amount of fish discarded 

 owing to restrictions (trip limits) on keep- 

 ing some species. A fishing vessel observer 

 program may be necessary to develop this 

 estimate. 



The problem of monitoring discarded 

 fish is tied in with the many species caught 

 during a fishing trip. We know little of the 



true probability that species are caught 

 together and of the fishermen's ability to 

 alter these probabilities by selective fish- 

 ing. Thus, we are unable to predict how 

 changes in a single-species trip limit will 

 affect the catch and discard of different 

 fishes caught together. We also have made 

 little progress in managing species that are 

 caught together and which have different 

 productivity levels (e.g., thornyheads 

 caught with Dover sole). Questions of bio- 

 logical interactions among species are 

 even further from our level of understanding. 



Allocations 



Allocation of "available catch" to different 

 groups is a difficult and sometimes contro- 

 versial management problem. The Fishery 

 Management Council must cope with a 

 (J.S.-Canada whiting allocation, onshore- 

 offshore whiting allocation, fixed gear-trawl 

 allocation of sablefish, and recreational- 

 commercial competition for some rock- 



fishes. Technical assessment of these is- 

 sues generally rests on an economic anal- 

 ysis that rarely has adequate information 

 on all sectors of the fishing industry. For 

 some of these problems, individual trans- 

 ferable shares have been identified as a 

 potential long-term solution. 



