Status of Current Information 



In the past, estimates of fisheries yields and 

 advice on the health and viability of stocks has 

 been given to management bodies like the In- 

 ternational Commission for Northwest Atlan- 

 tic Fisheries (ICNAF) without disclosure to 

 the general public and with little involvement 

 of domestic fishermen or other interest 

 groups. The new Regional Councils could 

 make a substantial improvement in this pro- 

 cedure by interpreting scientific data on 

 stocks, publishing and widely disseminating 

 stock data and advice, and providing an op- 

 portunity for continual access to information 

 and debate of the issues by interested parties. 

 Good scientific data by itself will not promote 

 conservation or adequate management of 

 stocks. Input by and involvement of users and 

 other public parties is crucial. 



At present, most population estimates of 

 heavily utilized stocks appear to be quite ac- 

 curate, in spite of some problems in gathering 

 information and evaluating the effects of fish- 

 ing activity decisions. However, projections of 

 sustainable yields in the future are subject to 

 large uncertainties due to effects of in- 

 terspecies relationships, environmental 

 change, fishing effort, and other unknown 

 natural variations. 



Public Law 94-265 has put tremendous 

 pressure on the stock assessment science to 

 provide a major part of the data base upon 

 which quotas are set and restoration strategies 

 are determined. However, presently no stock 

 has adequate quantitative data on all items 

 necessary to develop estimates of maximum 



potential yields that can be harvested without 

 reducing the parent stock. The information 

 necessary includes :66 



• an understanding of species-stock 

 biology; 



. quantification of the commercial indices 

 which allow trends in abundance to be 

 followed; 



. survey information that demonstrates 

 changes in total stock abundance and age 

 composition; 



. survey information giving pre-recruit in- 

 dices; 



. accurate knowledge of species/stock 

 abundance and area location; 



. accurate age and size composition; 



. historical catch-effort data; 



• understanding of movements and migra- 

 tions; 



. knowledge of the effect of such factors as 

 temperature and water quality; and 



. knowledge concerning the interrelated- 

 ness among species. 



Historically stock assessment has studied 

 individual populations of fish, and the 

 biological basis for management has thus con- 

 centrated on the "single species" approach. 

 This approach has assessed the resource po- 

 tential of one or another species of fish that 

 has had commercial value to fishermen or that 

 has promise of future value. However, to be of 

 the most use in setting optimum yields, stock 

 assessments must take a multispecies ap- 

 proach, looking at the relationship of one 

 species to the survival of another. Biologists 

 have not yet developed a multispecies ap- 

 proach which is generally accepted by the 

 scientific community. 67 



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