1601 



Saila, Saul B ., and Thomas A. Gaucher. 1966. 



Estimation of the sampling distribution and numerical abundance of some > 

 molluscs in a Rhode Island salt pond. Proc . Natl. Shellfish Assoc. 56: 

 73-80. 



Mercenaria (Venus) mercenaria is not mentioned. - J.L.M. 



1602 



Saila, S. B., and S. D. Pratt. 1973. 



Mid-Atlantic Bight Fisheries. In Coastal and offshore environmental 

 inventory, Cape Hatteras to Nantucket Shoals. Mar. Exp. Sta. , Grad. 

 School of Oceanogr., Univ. Rhode Island, Mar. Pub. Ser. 2: 6-1 to 6-125. 



(Abstract of hard clam section only: 6-30 to 6-34J Range is from Gulf of 

 St. Lawrence to Gulf of Mexico in shallow bays and coves. Southern quahog , 

 M. campechiensis , extends north to Point Pleasant, M.J., and is almost 

 completely oceanic. Second most valuable mollusk fishery in Middle Atlantic 

 Bight in 1960s. At age one year and length one cm almost all have mature male 

 gonads. By end of second year approximately 50% become sexually mature 

 females. Spawn from late spring to mid-August at temperatures above 20°C. 

 In salinity 21°/°° and water temperature 25-30°C larvae set by end of 7 days. 

 Under natural conditions setting probably takes longer. Hard clams are 

 filter feeders. Maximum growth is in summer. Clams enter the fishery at age 

 2 to 3 years and about 3.5 cm long. After setting, clams burrow into bottom, 

 usually sand or sand-clay. Juveniles and young adults are prey to crabs, 

 lobster, and snails. Adults are more resistant. Hard clam can resist high 

 levels of water pollution and can survive low oxygen. Large numbers may be 

 found in polluted waters, where competitors, predators, and man may offer 

 little threat. In New York by 1970 about 157,000 acres of clam beds were 

 closed to shellf ishing. Research on management strategies is needed now. 

 - J.L.M. 



1603 



Saila, S. B., J. M. Flowers, and R. Campbell. 1965. 



Applications of sequential sampling to marine resource surveys. Ocean. Sci. 

 Ocean Eng. 2: 782-802. 



Decisions on sample sizes traditionally have been predetermined, based on 

 characteristics of a single sample. Sequential analysis, developed during 

 second world war, relies upon information gathered during a survey to 

 determine optimum sample size on basis of numbers of organisms taken and 

 their variability. The method is here illustrated from data gathered in 

 surveys of distribution and abundance of Meroenavia mevcenarta, presumably 

 in Rhode Island waters, with a construction bucket and a Fall River dredge. 

 The negative binomial distribution fitted data gathered with the bucket; 

 standard towed dredge data followed the normal distribution. In marine 

 resource surveys, areas of interest are large and heterogeneous with respect 

 to environmental variables. Even in relatively uniform areas hard clams tend 

 to cluster. A large area must be subdivided into as many uniform subareas as 

 required, if this sampling plan is to be effective. The sequential plan is 

 then applied to each subarea . Data may be combined or averaged as necessary. 

 Greatest advantage of the method is to save time. - J.L.M. 



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