in low-salinity waters and in ponds on Horn and Cat Islands. Red algae 

 made up a large part of the marine flora of Mississippi Sound, based 

 on abundance and species diversity. Brown algae were found along with 

 red algae. Green algae occur in abundance along the mainland shore in 

 Spartina alterniflora marshes and on oyster shells in the brackish 

 bays. The approximate acreage of Mississippi Sound covered by submerged 

 marine spermatophytes and algae is presented. 



Copepods were the dominant zooplankton group. Acartia tonsa was the 

 most abundant plankton species. 



The influence of the ctenophore Mnemiopsis mccradyi on plankton 

 volume is discussed. These predators probably play a large role in 

 regulating the distribution and abundance of local plankton populations. 



The occurrence, relative abundance, seasonal and areal distribution, 

 and distribution of invertebrates within the salinity-temperature matrix 

 collected in trawl, seine and sediment samples in the Mississippi 

 Estuarine Study Area were reported. White shrimp and brown shrimp 

 were the two most abundant species. Shrimp, crabs and oysters provided 

 all of the reported commercial landings of invertebrate species. 

 Squid ( Lolliguncula brevis ) was the fourth most abundant species. 



The occurrence, relative abundance, seasonal and areal distribution, 

 distribution in the salinity-temperature matrix, spawning and growth 

 rate of fishes collected with trawls and seines in the Mississippi 

 estuarine study area were reported. A list of 294 fish species 

 from Mississippi estuaries and continental shelf waters off Mississippi 

 included 251 species observed in the estuarine study area. The bay 

 anchovy ( Anchoa mitchilli ) , largescale menhaden ( Brevoortia patronus ), 

 Atlantic croaker [ Micropogon undulatus ), spot ( Leiostomus xanthurus ), 

 butterfish ( Peril us burti ) and sand seatrout ( Cynoscion arenarius ) 

 comprised 93 percent of the total number of fishes collected. Over 

 93 percent of the number of fishes caught were in the families 

 Engraulidae, Clupeidae and Sciaenidae. The role of other vertebrates 

 in the study area is discussed. 



The bay anchovy was not sought by commercial fishermen. The other 

 five species most abundant in the study area contributed about 93 

 percent of the total commercial finfish landings in Mississippi. 

 CA.A. and B.W.) 



Keywords: estuarine areas, coastal marshes, plankton, aquatic fauna, 

 marsh grasses, Mississippi 



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