APPENDIX III APPENDIX III 
Cyclical increases in the green crab population is a 
major problem to soft clam resource availability. Soft clams 
are a favored food item of the green crab. To combat this 
problem, Maine is providing funds to aid construction of 
fences to help keep the green crabs away from the small soft 
clam. 
Pollution in coastal areas, particularly bacterial con- 
tamination, represents the greatest obstacle to the soft and 
hard clam resource. Other pollutants include oil and heavy 
metals. Pollution is responsible for closing about 21 per- 
cent of the clam flats in the leading soft-clam-producing 
State and about 25 percent of the clam flats in the two lead- 
ing hard-clam-producing States. Interim solutions include 
transplanting contaminated clams to clean waters or to 
depuration plants, facilities where clams can be cleansed be- 
for marketing. Ultimately, the solution is effective pollu- 
tion abatement. 
Another problem relates to occasions when the clam's 
body accumulates paralytic shellfish poison (PSP), a toxin 
produced by microscopic plants. Although not normally a 
problem, these plants occasionally bloom explosively causing 
the so-called red tide. Clams can accumulate a sufficient 
quantity of the toxin to cause illness or death to people 
eating them. State and Federal agencies monitor for red 
tide and prohibit harvesting and sale of affected shellfish. 
The toxin may remain for several months, and there is no 
known method to hasten the natural process of detoxification. 
A Washington Department of Fisheries study estimates 
that there are 100 million pounds of subtidal hard clams in 
the State; however, only a few million will be available for 
commercial harvest. Many clam beds identified will not be 
harvested because the ocean floor may not be conducive to 
mechanical harvesting, the water may be too deep or too 
rough for existing gear, or the clam beds may be closed be- 
cause of pollution. Adverse public reaction to the com- 
mercial clam harvest by mechanical dredge may also restrict 
future availability. 
In 1965 Washington stopped issuing commercial clam dig- 
gers' licenses, Since only a small amount of public land was 
available within the bays and most of this was needed for 
expanding recreational demand. Although the individual com- 
mercial clam digger was eliminated from public land, the 
State continued to issue a clam-farming license. This li- 
cense allowed clam growers to commercially produce clams 
from private areas. 
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