the Pacific coast, none have occurred consistently 

 enough to indicate that they are associated with the 

 observed mortalities. 



In a new project, agraduate student at the Univer- 

 sity of Washington College of Fisheries in Seattle is 

 investigating the relationship between the bacterium 

 Vibrio anquiUaritm or V. ptiraluiemulyticiis and oys- 

 ter mortalities. He has observed that Vibrio can kill 

 oysters at elevated temperatures in laboratory ex- 

 periments, but field tests have not yet been 

 made. 



Efforts of Washington State Department of 

 Fisheries have recently been reoriented to develop 

 new oysterculture techniques which will circumvent 

 oroffset mortalities. Forexample. transplanting par- 

 tially grown oysters to low mortality areas before the 

 second summer when heavy mortalities begin seems 

 to be a practical solution. Also, improvement of 

 handling methods for seed to reduce losses would 

 help to offset mortality which might occur during the 

 second summer. 



In summary, mass mortalities significantly reduce 

 production and profits in specific locations, but 

 other areas remain unaffected. Research to deter- 

 mine causative factors is still in progress. 



NEW DEVELOPMENTS IN CLAM 

 PRODUCTION 



Ocean beaches on the Pacific coast are owned by 

 the states and held for public use. This prevents the 

 private commercial development of farming for 

 species such as the razor clam or Pismo clam which 

 occur only in this habitat. 



The inteilidal zone in bays or estuaries is also 

 owned by the states, but much of this land, espe- 

 cially in the State of Washington, has been sold to 

 individuals who are usually the owners of the adja- 

 cent upland. Large areas of intertidal zone have also 

 been leased by the states to individuals or companies 

 for special purposes, such as oyster and clam cul- 

 ture. Subtidal bottoms also can be leased to indi- 

 viduals or companies for aquaculture. 



Farming of clams has not reached the stage of 

 development attained by oyster culture. The few 

 commercial clam farms on the U.S. Pacific coast still 

 depend upon natural setting to restock their beds. 

 Clam farming is still only selective harvesting of a 

 natural crop to obtain the greatest yield. 



Until recently there has been no source of "seed" 

 clams which might be used for planting on private 

 lands and this has been a major deterrent to clam 



farming. Now a commercial hatchery in California 

 has successfully produced large quantities of young 

 Manila clams and has offered these for sale. Test 

 plantings have been made in Willapa Bay, Wash., 

 and in some other locations, but it is too soon to 

 evaluate the success of these ventures. 



I had the opportunity in March 1971 to obtain a 

 small quantity of these seed clams from California 

 and to plant them in trays in the Fiji Islands. Survival 

 of clams was excellent, but growth was not outstand- 

 ing. This experiment is still in progress, but it is 

 already apparent that the first step in the develop- 

 ment of commercial farming forclams, availability of 

 seed, has been accomplished. With the large demand 

 for clams and the limited supply, it is likely that a 

 new clam farming industry will develop in Washing- 

 ton State within the next few years. 



Three new developments in the utilization of 

 natural stocks of mollusks occurred in Washington. 

 Exploratory diving and population assessment by 

 scientists of the Washington State Department of 

 Fisheries have shown that less than 5*^ of the 

 geoduck clam, Fanope ^cnerosa Gould, 1850, are 

 exposed at extreme low tide. Before this discovery it 

 was thought that the geoduck was a scarce species 

 which needed stringent regulation to prevent over- 

 harvesting. No commercial digging had been permit- 

 ted and the recreational or personal use limit was set 

 at three clams per day. 



Now Washington has surveyed subtidal beds and 

 established a system for leasing areas for commer- 

 cial harvest by scuba divers using suction pumps. 

 The product is now achieving market acceptance 

 and a new industry has been established. 



Another species of clams, Mya arenariu 

 Linnaeus, 1758, known as the soft-shell clam in New 

 England and Chesapeake Bay, is present in 

 Washington but has not been utilized commercially. 

 This clam has a somewhat less attractive appearance 

 than the local littleneck and butter clams, and tradi- 

 tionally it has not been marketed in the Pacific 

 Northwest. Heavy concentrations of soft-shell 

 clams are found in muddy or sand\ beaches, usually 

 at the mouths of rivers, but areas suitable for these 

 species are rather limited. 



Recently several individuals or companies have 

 begun harvesting soft-shell clams using two types of 

 hydraulic dredges to minimize labor costs. One type 

 similar to that used in Chesapeake Bay is operated 

 from a boat and consists of a digging head which is 

 forced through the bottom and a conveyor to bring 

 the clams to the surface. The second type is hand- 



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