. . . Issues of National Concern 



18 



. . . INSUFFICIENT 

 INFORMATION ON THE 

 STATUS OF LIVING 

 MARINE RESOURCES 



Uncertainty about the relationship be- 

 tween marine mammals and fisheries now 

 threatens both. For example, it is possible 

 that trawl fisheries in the Bering Sea are 

 adversely affecting Steller sea lion popula- 

 tions, but there is little scientific basis for 

 drawing a sound conclusion. The outcome 



of making management decisions without 

 sufficient information could be that a valu- 

 able fishery is unnecessarily restricted to 

 protect Steller sea lions or that the fishery 

 unknowingly contributes to the demise of 

 the Steller sea lion. 



ENVIRONMENTAL 

 QUALITY 



Ultimately, the persistence of LMR popula- 

 tions depends on the "quality" of their en- 

 vironment. The effect of environmental 

 quality on LMR's is most apparent for 

 anadromous salmon stocks (both Atlantic 

 and Pacific), many of which have been 

 harmed by hydroelectric power develop- 

 ment and other causes of habitat degrada- 

 tion, such as massive water diversions for 

 agriculture and urban development. As a 

 result, some west coast salmon stocks are 

 in danger of extinction (e.g., Snake River 

 sockeye and Sacramento River winter 

 chinook). 

 Another apparent impact of environ- 



mental quality on fisheries is the wide- 

 spread closure of inshore shellfish beds 

 owing to contamination by pathogens and 

 biotoxins (i.e., coliform bacteria and para- 

 lytic shellfish poisoning). For example, 

 83% of the shellfish production acreage in 

 Massachusetts has been closed (Table 4). 

 The effects of environmental quality on 

 other fishery resources is difficult to detect 

 and quantify, but there are disturbing 

 signs. For example, chemical contami- 

 nants in Boston Harbor and Puget Sound 

 are the most probable causes of tumors in 

 winter flounder and English sole, respec- 

 tively. 



Table 4. — Shellfish closures in 



the Gulf of Maine. 



Region 



Massachusetts 

 New Hampshire 

 Maine 

 Nova Scotia 

 New Brunswick 



l Year of closure 



