fauna inhabiting the Lake Pontchartrain-Lake Maurepas estuarine complex, 

 so that comparisons with previously completed wetland research in 

 Louisiana and the northern Gulf of Mexico might enable administrators 

 to efficiently manage Louisiana's renewable coastal zone resources. 



Vertebrate and macroinvertebrate populations were sampled with a 

 16-foot trawl and a 100-foot beach seine. Molluscan benthic communities 

 were empirically determined utilizing a Peterson dredge. Zooplankton 

 was estimated based upon collections accomplished utilizing a No. 2 

 mesh 1.8 x 0.5 meter net. Hydrological and climatological parameters 

 were collected at four stations in addition to those coinciding with 

 trawl, seine, Peterson, and zooplankton locations. Grain size determinations 

 were made of the upper three inches of sediment samples during two 

 separate sampling efforts--one in 1972 and another in 1973. (A. A.) 



Keywords: estuaries, fisheries, marine organisms. Lake Pontchartrain- 

 Lake Maurepas, Louisiana 



IV-D-14 



Lantz, K.E. 1970. An ecological survey of factors affecting fish 



production in a Louisiana natural lake and river. Louisiana Wildlife 

 and Fisheries Commission, Fisheries Bulletin No. 6. 92 pp. 



This report is a result of a project conducted in the Sabine River 

 and Lac Des Allemands from July 1964 through June 1967. The 

 objectives of this study were: (1) to establish quantitatively what 

 types of aquatic areas are rich, average, and poor in the production 

 of fish and fish food organisms, (2) to determine what cycles occur 

 in the kinds and abundance of plankton and bottom fauna, and (3) to 

 correlate these cyclic occurrences of fish food organisms with variance 

 in fish production in the study areas. Four stations in the Sabine 

 River and three stations in Lac Des Allemands were chosen as sampling 

 sites. 



It was found that plankton production in the Sabine River began to 

 Increase by February of each year, but counts and weights of net 

 and nannoplankton revealed sporadic high to low values from month 

 to month without predictable trends toward summer maximum productivity. 

 The lack of an extended period of high plankton density was associated 

 with peak stream discharges. 



The upper stations on the Sabine River exhibited higher seasonal 

 numbers, volumes, and weights of bottom organisms than found at the 

 two lower stations. Maximum production of bottom fauna occurred each 

 spring in the river. 



The two major benthic groups in Lac Des Allemands were Tubificidae 

 and Chironomidae, with Chironomidae species being most abundant during 



169 



