The conchs Fulgur and Sycotypus are hardy and live well in captivity. Fulgur 

 probably attacks any lamellibranch, Sycotypus attacks any except Venus. 

 Quahogs are eaten in from 7 hrs to 3 days. The radula is not used to bore 

 holes. Shells of oysters are opened by wedging the conch shell between the 

 valves. The radula is used to tear out flesh. Quahaugs probably are eaten 

 in the same way. Some conch shells are injured in the process. Meals are 

 infrequent, and the conch buries in sand between feedings. Conchs may not 

 be as serious a pest as oystermen believe. Illustrations of the feeding 

 method are included. With oysters Fulgur crawls on top and waits until the 

 oyster opens its valves, the process is then very rapid. Hard clams never 

 open their valves voluntarily, and the snail uses the edge of its shell to 

 chip away pieces from the edge of the clam shell. When the opening is 3 mm 

 or more the proboscis is then inserted, or the snail inserts the edge of 

 its shell into the gap and pries the clam open by contracting its columellar 

 muscle. - J.L.M. 



375 



Committee on Merchant Marine and Fisheries. 1963 



Molluscan shellfish. Hearings before the Subcommittee on Fisheries and 

 Wildlife Conservation of the Committee on Merchant Marine and Fisheries, 

 House of Representatives, 88th Congress, First Session. Serial No. 88- 

 13. U.S. Govt. Printing Office, Washington, D.C., v+229 p. 



A comprehensive hearing on the many problems of the shellfish industry 

 of the United States. Witnesses were drawn from all sections of the 

 country, and included government experts as well as representatives of 

 industry. Hard clam is mentioned many times in the testimony and the 

 questioning of witnesses. - J.L.M. 



376 



Connell, L. R. , Jr., and R. E. Loveland. 1980. 



Growth rates and fouling in sediment-free raft culturing of juvenile hard 

 clams, Mereenaria meroenaria, L. Natl. Shellf. Assn., Abstracts, Technical 

 Sessions: 15 (abstract). 



Juvenile clams, collected from natural Mereenaria intertidal beds, were placed 

 in plastic trays suspended from plastic flotation collars in the intake canal 

 of a nuclear power plant. Clams ranged from 2 to 15 mm long and were main- 

 tained according to a size-frequency distribution similar to a natural popu- 

 lation under study. Mortality in 5 months was less than 10% as compared to 

 nearly 90% for juveniles in natural beds. Maximum growth rate in sediment- 

 free trays was 0.4 mm/week in September 1979. Mortality was 5% or less in 

 trays which held sediments in the range of 0.5 to 1.0 mm grain size and 

 which were covered with galvanized wire mesh. - J.L.M. 



377 



Conrad, Jon M. 19 79. 



Management of the Northeast clam resource: Commercial and recreational con- 

 siderations. In Proc. Northeast Clam Industries: Management for the 

 Future. Ext. Sea Grant Advisory Proaram, U. Mass., and MIT Sea Grant Pro- 

 gram, SP-112: 121-129. 



The report is largely speculative, but contains some interesting estimates. 

 For example, Massachusetts communities with active recreational shellf ish- 

 eries in 19 7 5 were estimated to be worth between $571 and $3,850 thousand 

 dollars. Comparing these with commercial values for the same places, on 

 one basis, the commercial harvest was worth approximately $788 thousand, the 

 recreational harvest between $31 and $195 thousand; on another basis, the 

 average price for a bushel of commercially harvested hard clam was $15.73, 

 the per bushel value of the recreational catch was between $3.44 and $20.42 

 for one place and $4.28 and $32.17 for another. Thus, the per-bushel valu- 

 ations might be approximately the same. Inshore shellf isheries provide 

 opportunities for resource enhancement not found in most finf isheries . The 

 comparisons possible, with limited- information suggest that additional in- 

 vestment would be justified. There does not appear to be any consensus that 

 nearshore shellfish beds have been excessively overfished. The opportunities 



104 



