Aquaculture developments are providing the basis for important con- 

 tributions to resource and economic development. The objective of the 

 Federal effort is to develop the methodology and demonstrate the biological, 

 economic, and engineering feasibility of aquaculture systems as a means of 

 establishing fisheries under man's control. Basic NOAA programs provide 

 important spinoff information which is critical for the development of a 

 commercial aquaculture system. 



A Sea Grant-supported private company demonstrated that chinook and 

 coho salmon can be reared in floating net pens with good feed-conversion ef- 

 ficiencies. This commercial-scale demonstration in Puget Sound began in 

 November 1970 with 700,000 coho eggs. The coho fry, together with 500,000 

 chinook fry, were reared in fresh water in a conventional way except for 

 the use of heat to speed growth. In the summer of 1971, 500,000 juveniles 

 were transferred to salt-water rearing pens. The fish are to be harvested at 

 pan size during the spring of 1972. (Other Sea Grant activities are discussed 

 in chapter VI.) 



Quality Assurance 



Various types of screening activities are carried out by FDA to insure that 

 only safe, wholesome fishery products reach the consumer. Factors govern- 

 ing the toxigenicity of C. botulinum in certain fishery products were defined 

 last year to provide a reliable margin of safety in the distribution and storage 

 of semipreserved fishery products. Selected fishery materials and processed 

 products were screened to identify species and situations in which potential 

 hazards could exist because of the presence of toxic materials such as mercury 

 and pesticides. 



Studies during 1971 aimed at defining the extent of mercury contamination 

 of fishery products indicated that virtually all edible salt-water fish offered on 

 the American market were safe and wholesome. Initial alarms regarding 

 tuna turned out to be of little real concern after analysis of the U.S. canned 

 tuna supply, which showed that less than 4 percent of the fish examined 

 exceeded the FDA mercury guideline of 0.5 part per million. FDA labora- 

 tories conducted an intensive survey of the 19 most important commercial 

 fish for mercury contamination and found the levels of mercury in salt-water 

 fish to be quite low, about 0.09 part per million. From over 1,000 lots ex- 

 amined, the FDA initiated seizure or recall actions against 14 lots of snapper, 

 three lots of bonito, and three lots of mackerel. 



Swordfish was the only species which consistently exceeded FDA mercury 

 guidelines. Swordfish from all cold storage facilities and points of entry into 

 the United States were examined for mercury early in 1971. This survey 

 revealed that only 42 of 853 swordfish sampled were within the guideline 

 and 53 percent contained mercury concentration exceeding 1 part per mil- 

 lion. Accordingly, on May 6, 1971, the Commissioner of Food and Drugs 

 issued a public warning against the consumption of swordfish. 



NOAA is vigorously pursuing a series of programs aimed at determining 

 the levels and effects of heavy metals occurring in fish and fishery products. 

 The effort here has concentrated on major fishery products — Pacific halibut, 

 northern lobster, cod, haddock, pollock, sole, black cod, fishmeal, billfish, 

 tunas — going to consumers. One result of this activity is a procedure that 



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