SECTIUN 20 

 Sea Scallop {Flaocveaien magallanicus) 



Life History Summary 



The sea scallop is found in the Northwest Atlantic Ocean from northern 

 Newfoundland to the Virginia Capes with the largest concentrations on Georges 

 Bank and the Mid-Atlantic shelf (MacKenzie 1979 and Posgay 1982) in depths 

 ranging between 4U and 100 m. In the Middle Atlantic Bight, sea scallops are 

 restricted to depths where water temperatures do not exceed 20°C. There are 

 apparently no directed movements or seasonal migrations, even though sea 

 scallops are active swimmers. 



The fishery for sea scallops is almost entirely commercial and, with the 

 exception of foreign (Canadian) fishery on the eastern end of Georges Bank, it 

 is entirely domestic. During 1983, the sea scallop fishery ranked first in 

 value on the east coast of the US, and fifth nationwide. During that year, 

 9,289 metric tons (MT) of meats, valued at $111.5 million, were landed in the 

 US (Thompson 1984). The sea scallop fishery has exhibited considerable 

 variability. During 1973, approximately 2,4UU MT of meats were landed, while 

 during 1978, approximately 14,4b0 MT of meats were landed, making sea scallops 

 one of the most valuable East Coast commercial species of that year. This 

 catch variability is due to unusual success or failure of a given year-class. 



Sea scallops become mature during the spriny when they lay down their 

 third annuli at a length of about 7b mm (Posgay 1982). Spawning in the 

 southern part of the range of the sea scallop occurs in July, and proceeds 

 northward, in a wave-like manner, so that spawning on Georyes Bank occurs in 

 late September and early October (MacKenzie et al . 1978). All scallops in a 

 localized area spawn at the same time for about a week. Gametes of both sexes 



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