METHODS 



The Sea Scallop Tagging Experiments 



Scallop collection and preparation. 



Sea scallops were collected with SCUBA in the vicinity of 

 Boothbay Harbor, Maine, during the summers of 1985 and 1986. 

 These scallops were brought back to the laboratory at the Maine 

 Department of Marine Resources and held in running seawater 

 aquaria. Each scallop was measured with vernier calipers along 

 its height, length and width axes, and would be remeasured to 

 determine its growth. The epizooic assemblages on the upper and 

 lower valves were photographed and then removed. 



Scallop treatments. 



Live tagged scallops were used to evaluate growth, movement 

 and mortality. In 1985 the live scallops were tagged with red 

 plastic numbers embedded in epoxy on the shell (Hudson 1972), and 

 in 1986 by inserting a green spaghetti tag through a hole drilled 

 in the upper valve above the byssal notch ( Posgay 1963). In 

 addition, dead tagged scallops were used as a control for 

 evaluating shell deterioration. These scallops were killed 

 immediately before release, and were kept in running seawater 

 aquaria so that the ligament and resilium of the shell hinge 

 would not deteriorate faster than natural. These scallops were 

 tagged by drilling a hole through both valves at the peripheral 

 margin adjacent to the umbo and then attaching an eight-inch 

 plastic cable-tie loose enough so that the shell could fall apart 

 naturally. 



The recaptured scallops were separated into five treatments 

 based on the potentially different shell habitats which could be 

 colonized by epizooic species. These were epizooic assemblages 

 on the exterior shell surfaces of the live tagged scallops which 

 lived (LIVETAG); on the exterior (LIVEDE); and interior (LIVEDI) 

 shell surfaces of the initially live tagged scallops which died; 

 and on the exterior ( DEADE ) and interior (DEADI) shell surfaces 

 of the initially dead tagged scallops. Thirty live scallops from 

 the local population (LIVE) also were collected. 



Cages were constructed to protect the experimental scallops 

 from being disrupted by commercial trawlers and to insure that 

 some of the experimental replicates would be retrieved. Five- 

 foot square cages were built from quarter-inch steel rods and 

 one-inch square plastic-coated wire mesh. Each cage was 

 constructed so that it could be opened and locked using a 

 submersible manipulator. Ten live and 10 dead scallops were 

 placed in each cage. Three cages were placed in each area so 

 that a cage effect ( Jamieson et al. 1982, Schmidt and Warner 

 1984) could be evaluated. Twenty-five live and 25 dead tagged 

 scallops were released adjacent to each of the cages, except 

 during 1986 when 65 live and 65 dead scallops were released 



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