AQUACULTURE OF MOLLUSCS ALONG THE UNITED STATES 



ATLANTIC AND GULF COASTS 



WILLIAM N. SHAW 



INTRODUCTION 



Today I would like to take you on a tour of the east 

 and gulf coasts of the United States to review the 

 past and present status of molluscan aquaculture. 

 Robert D. Wildman has already reviewed the cur- 

 rent molluscan aquaculture projects under the Sea 

 Grant Programs for this area, so I will cover these 

 projects only briefly in my presentation. Because of 

 the limited time. I plan to center my discussion 

 around the culture of three species of molluscs, the 

 Eastern oyster, Crassostrea virginica; the hard 

 clam, Mercenaria mercenaria: and the bay scallop, 

 Aeqiiipecten irradians. Although there are other im- 

 portant commercial molluscs found along our east 

 and gulf coasts, such as the surf clam, SpisuUi 

 solidissima: ocean quahog, Articci ishindka; sea 

 scallop, Placopecten magellanicus; sunray venus, 

 Macrocallista nimhosa: calico sc^Wop. Aeqiiipecten 

 gibhiis: and the soft-shell clam, Mya urenarici. these 

 species are being hunted. Little or no attempt is 

 being made to farm these species at the present time. 



I will review the fishery for the oyster, hard clam, 

 and bay scallop and describe past and present at- 

 tempts to farm each species. 



THE EASTERN OYSTER 



The Eastern oyster, Crassostrea virginica, (also 

 called the American or Virginia oyster) ranges along 

 the entire east and gulf coasts. Peak of production, 

 near 170 million pounds, was reached in the I890's. 

 Since then, landings have been on the decline with an 

 apparent leveling off in the I960"s — around 50-60 

 million pounds (Engle, 1966). Unlike Japan, oysters 

 along the east and gulf coasts are grown almost en- 

 tirely on the bottom. The national average is re- 

 ported to be only 0.004 tons per acre per year, while 



' Middle .Mlantic Coastal Fisheries Center. National Marine 

 Fisheries Service. NO.A.A. Oxford. MD 21654. 



the best yield on the bottom is 2.0 tons per acre per 

 year (Ryther and Bardach, 1968). These yields are 

 extremely low when compared to those of Japan 

 where 23.3 tons per acre per year are being harvested 

 using off-bottom methods. 



Not only are most of the U.S. methods of growing 

 oysters extremely primitive, but so are our ways of 

 harvesting. In Maryland, the state that has the 

 largest annual production of oysters, oystermen 

 catch oysters with hand tongs and patent tongs and 

 in dredges pulled along the bottom by sailboats. 

 Laws in this state prevent the use of more mechani- 

 cal means such as the hydraulic dredges, except on 

 private leases. 



Realizing that the production of oysters has been 

 on the decline, many private companies, state and 

 federal agencies, and universities have in recent 

 years initiated programs in an attempt to modernize 

 the oyster industry. I would like to review some of 

 these programs at this time. 



New Hampshire 



Under the U.S. Government's Federal Aid Pro- 

 gram the State of New Hampshire has for 3 yr 

 (1966-69) investigated the possibility of producing 

 seed oysters and growing oysters using off-bottom 

 techniques (Ayer, Smith, and Acheson. 1970). New 

 Hampshire is at the northern limit of the oyster's 

 natural range, and because of the cold waters, 

 growth is slow. Still in certain areas, like Great Bay, 

 the water warms sufficiently so that the natural oys- 

 ter populations can spawn and setting does occur. It 

 appears from their studies that a limited amount of 

 seed could be produced annually, but intensity 

 would vary greatly from year to year. 



Massachusetts 



Production of oysters in Massachusetts is small 

 and only 72,100 pounds of meats were harvested in 



57 



