American oyster 



Crassostrea virginica 

 Adult 



2 cm 



(from Galtsoff 1964) 



Common Name: American oyster 



Scientific Name: Crassostrea virginica 



Other Common Names: Eastern oyster (Turgeon et 



al. 1988), huitre creuse americaine (French), ostion 



americano (Spanish) (Fischer 1978). 



Classification (Turgeon et al. 1988) 



Phylum: Mollusca 



Class: Bivalvia 



Order: Ostreoida 



Family: Ostreidae 



Value 



Commercial : The American oyster has historically sup- 

 ported a valuable fishery throughout the Gulf of Mexico 

 (Stanley and Sellers 1986). In 1993, 15,241 metric 

 tons (mt) of oyster meat valued at $86.7 million were 

 landed in the United States, and the Gulf region led in 

 production with 9,072 mt of meats (O'Bannon 1994). 

 Led by Louisiana, the Gulf region produced about 

 8,390 mt and nearly 41% of the national total during 

 that year. Individual state harvests for the Gulf during 

 1 992 have been compiled by Newlin (1 993). The west 

 coast of Florida ranked second in Gulf production with 

 1,571 mt harvested during that season. Alabama and 

 Mississippi landings are typically small, but landings 

 during 1992 were much higher than usual totaling 543 

 and 321 mt respectively. Louisiana led the Gulf states 

 in production during that year with 5,015 mt of meats. 

 In Texas, the harvest was about 936.7 mt. Harvest 

 methods include hand picking, tonging from boats, and 

 dragging or dredging from boats (Stanley and Sellers 

 1986). Most of the Gulf landings are from publically- 

 owned oyster beds, but an estimated 30% of the 

 harvest isf rom privately-leased beds (MacKenzie 1 989). 

 Oysters from restricted waters are sometimes moved 

 to approved waters for depuration or further growth. 



Broken oyster shell, rangia shell, or limestone are 

 sometimes used as substrate to enhance oyster settle- 

 ment and growth in Florida and Louisiana (MacKenzie 

 1996). Commercial fishery regulations vary among the 

 Gulf coast states, but all oysters harvested must mea- 

 sure at least three inches from hinge to mouth (GSMFC 

 1 993, TPWD 1 993a). A regional fishery management 

 plan has been developed for this species (Berrigan et 

 al. 1991). 



Recreational : Oysters are often collected from ap- 

 proved areas for personal use by hand (cooning), 

 tongs, or sport dredges. Recreational fishery regula- 

 tions vary among the Gulf coast states, but a three inch 

 minimum size limit generally applies, along with bag 

 limits and closed seasons (GSMFC 1993, TPWD 

 1993b). 



Indicator of Environmental Stress Oysters are ideal for 

 use as indicators of pollution due to their sessile, filter 

 feeding life mode (NOAA 1 989). Broutman and Leonard 

 (1 988) review the methodology and problems of water 

 classification, predominantly based on fecal coliform 

 bacteria, for shellfish throughout the Gulf of Mexico. 

 The American oyster is often used for pesticide and 

 petroleum by-product LD-50 analyses. It is used by 

 NOAA's Status and Trends program and other state 

 and federal agencies to monitor concentrations and 

 accumulation of organic and metallic contaminants in 

 the marine environment (Lytle and Lytle 1982, Mo- 

 rales-Alamo and Haven 1982, NOAA 1989, Wade 

 1 989, Sericano et al. 1 990, Alvarez et al. 1 991 , Palmer 

 et al. 1 993). In addition, shell thickness and condition 

 is used to detect heavy metal pollution (Marcus et al. 

 1989). This species has also been used by the U.S. 

 Environmental Protection Agency (EPA) to study the 



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