I-A-9 



Copeland, B.J., K.R. Tenore, and D.B. Horton. 1974. Oligohaline regime. 

 Pages 315-357 JH H.T. Odum, B.J. Copeland, and E.A. McMahan, eds., 

 Coastal ecological systems of the United States, Vol. 2. The Conservation 

 Foundation, Washington, D.C. 



The two major characteristics of oligohaline systems are low 

 salinity and great shocks of freshwater floods. Several examples of 

 such systems are discussed in detail: Pamlico River estuary. North 

 Carolina; Sacramento-San Joaquin estuary, California; Baltic Sea, 

 U.S.S.R.; and Lake Pontchartrain, Louisiana. Information is presented 

 graphically and in narrative form. 



Organisms capable of surviving the vigors of the system are few, 

 but those that do manage to survive flourish at certain seasons of the year. 

 Important adaptations include physical attachment to objects to avoid being 

 swept away during high flow rates and the ability to withstand salinity 

 variations. 



Plants in the oligohaline regime include such freshwater forms as 

 Najas and Potamogeton and the brackish water plant Ruppia maritima . 

 Fauna include certain molluscan species that have special filtering 

 ability to utilize the tremendous organic content of the muddy river 

 water. Macoma balthica , Rangia cuneata , and Nereis succinea are 

 common inhabitants of various oligohaline systems. 



Migrating subsystems are important constituents of the oligohaline 

 system and channel much of the energy harvested by man. Common among 

 these migrating forms are the herring-like plankton feeding fishes 

 represented by menhaden ( Brevoortia patronus ) on the Gulf of Mexico 

 coast, shad ( Alosa sapidissimus ) and menhaden ( Brevoortia tyrannus ) 

 on the Atlantic coast, shad (A. sapidissimus ) and herring ( Clupea 

 pallasi ) on the lower Pacific coast, and herring and cod in the 

 Baltic Sea. Other migrating forms include carnivorous striped 

 bass ( Roccus saxatilis ) on the east and west coasts of the United 

 States. 



In spite of the low diversity and biomass of organisms in the 

 oligohaline systems, the systems are relatively highly productive because of 

 the constant influx of organic fuels via rivers from the land. (B.W.) 



Keywords: aquatic ecosystems, coastal waters, salinity, filter feeders, 

 menhaden, fishes, biomass, U.S. coastal regions 



