146 



Becker, Dean Scott. 1978. 



Evaluation of a hard clam spawner transplant site using a dye tracer tech- 

 nique. Thesis presented in partial fulfillment of the requirements for the 

 Degree of Master of Science, State Univ. of N.Y., ix + 63 p. 



The hard clam, Mercenaria mercenaria , spawner transplant site of the Town of 

 Islip, N.Y. was evaluated with a water-soluble fluorescent dye tracer for 18 

 days. Dye was measured with a fluorometer from a small boat. The pattern 

 of dispersion suggested that the site is in an undesirable location for maxi- 

 mizing the set of larvae within town waters. An alternative site was recom- 

 mended, and ways in which Islip can maximize setting densities within Town 

 waters from planted spawners were suggested. - J.L.M. 



147 



Beedham, G. E. 1958. 



Observations on the mantle of the Lamellibranchia. Quart. J. Microsc. Sci. 

 99(2): 181-197. 



148 



Behrens, William John. 19 78. 



Heavy metals in transplanted hard clams, Mercenaria mercenaria , in Great 

 South Bay, New York. Thesis presented in partial fulfillment of the require- 

 ments for the Degree of Master of Science, State Univ. of N.Y., x + 51 p. 



Heavy metals are not considered in setting standards for hard clams in waters 

 closed to harvesting. Yet hard clam is known to concentrate heavy metals 

 from water and food. Digestive glands and kidney of hard clam contain the 

 highest concentrations, and eating the whole organism enhances ingestion as 

 compared with eating only muscle. The study was undertaken to determine if 

 levels of Cu, Pb, Cr, Cd, Ni, and Zn are higher in clams from an area closed 

 to shellf ishing, and if so are they depurated under current transplant prac- 

 tices. Clams were taken in Awixa Creek, marked, and transplanted to the 

 middle of the Bay. Variations in metal levels of clams from different areas 

 of the Bay were significant and may be caused by variations in availability 

 of metals or differences in biology of clams. Transplanted clams were 

 depurated of bacteria over a short period of time, but heavy metals remained 

 at their original levels or increased. The only metal that increased after 

 transplanting was Ni . - J.L.M. 



149 



Behrens, W. J., and I. W. Duedall. 1979. 



Heavy metals in transplanted hard clams, Mercenaria mercenaria , in Great 

 South Bay, New York. In Abstr. of Papers submitted for the 4 2nd Ann. 

 Meeting, Am. Soc . Limnol . Oceanogr., Mar. Sci. Research Ctr., State Univ. 

 of N.Y., Stony Brook, N.Y., June 18-21, 1979. 



An area of Great South Bay closed to shellfishing had elevated levels of 

 heavy metals in hard clams and sediments . Clams were transplanted from this 

 area into the central portion of the Bay, which is open to shellfishing. No 

 depuration of Cd, Cr, Cu, Ni, Pb, or Zn was noted over 50 days, but signifi- 

 cant increases in total body content of Cd, Ni, and Pb occurred. Cd and Pb 

 levels were not elevated above natural levels found in the transplant area, 

 but Ni levels were approximately 56% higher. Transplanting may therefore 

 introduce hard clams with significantly higher levels of Ni into the har- 

 vestable resource. Cu, Pb, and Ni levels in natural populations of hard 

 clam decreased from May to July, then increased through September, reflecting 

 seasonal trends associated with biological processes of the organisms and 

 environmental factors. - J.L.M. 



42 



