The International Mussel Watch 



An oyster knife (or other round-tipped blade) should be inserted between the shells at the 

 ligament and firmly twisted to dislocate the hinge, slightly separaring the shells. 



The shells can then be held apart firmly while the knife blade is carefully inserted between 

 the mantle and upper shell in the area of the adductor muscle. 



With the blade pressed as closely as possible against the inner shell surface, the adductor 

 muscle should be carefully cut. 



Once the adductor muscle is cut, the upper shell can be lifted off the oyster bode and 

 discarded (now have oyster-on-the-half-shell). 



The oyster tissue is removed from the lower shell by carefully inserting the knife blade 

 between the mantle and lower shell, cutting the adductor muscle and gently prying the oyster from 

 the shell. 



Place the removed, drained soft parts of about 100 individuals in a mortar; add a known 

 quantity of sodium sulfate and macerate the tissues with a pre-cleaned stainless steel knife and a 

 pestle. This constitutes the desiccated sample for chlorinated pesticide analysis. It should then be 

 stored in a pre-cleaned container for shipment. 



Place the 10 oyster bodies from each station into a 0.5 1 wide-mouth plastic jar prefilled 

 with Dietrich's fixative. 



Securely seal the jar, label it and store at ambient temperature. 



Check off the "Bivalve - Gonadal Index" box under "Samples Collected" on the Bivalve 

 Observations Log. 



1.7.7 Partitioning the Sample 



The bivalve sample should eventually be divided into three aliquots as follows: 



100 individuals (ca. 300 g wet wt.) 



Regional Lab Participating Lab Archives 



lOOgwetwt lOOgwetwt lOOgwetwt 



lOgdrywt lOgdrywt lOgdrywt 



2.5 g (1/4 of sample) ' 2.5 g 2.5 g 



for analysis 



75 mg lipid 75 mg lipid 75 mg lipid 



74 



