and 1970. The number of Penaeus aztecus in Airplane Lake and Lake 

 Palourde was declining at the opening of the 1969 commercial shrimping 

 season, whereas it was still rising at the opening of the 1970 season. 

 Growth rates increase as temperatures rise above 20°C and salinities 

 fall below 22 ppt. Growth estimates vary from a minimum of 20 mm per 

 month to a maximum of 45 mm per month. (A. A.) 



Keywords: brown shrimp, biomass, estuarine ecosystem, Louisiana 



IV-E-9 



Wilson, S.B. 1969. Ecological survey of penaeid shrimp of the central 



Louisiana Gulf coast and estuarine waters. Nicholls State University, 



Thibodaux, Louisiana. 140 pp. 



Brown shrimp, Penaeus aztecus , and white shrimp, Penaeus setiferus , 

 were studied to determine the environments in which they reside dur- 

 ing the post-larval, juvenile, and sub-adult stages of their lives. 



The dynamics and life cycle of the brown shrimp and white shrimp 

 are reasonably well established. Investigators are relatively cer- 

 tain that these shrimp require two completely different environments 

 for the successful completion of their life cycles. The adults spawn 

 and larvae hatch in the open Gulf waters; the post-larvae then seek 

 a brackish water estuarine habitat, completing development to sub- 

 adult before returning to the more saline waters. It is not completely 

 understood why these organisms migrate from a fairly stable environ- 

 ment, the sea, into one as unstable as the estuaries. Two factors may 

 influence this movement: (1) The protection from predators provided 

 by vegetation and shallow waters and (2) the abundance of organic 

 material. (H.D.) 



Keywords: estuaries, brown shrimp, white shrimp, Louisiana 



IV-E-10 



Barrett, B., and M.C. Gillespie. 1975. 1975 environmental conditions 

 relative to shrimp production in coastal Louisiana. Louisiana 

 Wildlife and Fisheries Commission Technical Bulletin 15. 22 pp. 



Shrimp catch data are presented along with environmental factors 

 which influence Louisiana's shrimp harvest. Environmental data for 

 the first four months in 1975 in the Barataria-Caminada Bay area are 

 compared with previous years. The relationship of the number of hours 

 during which water temperatures were below 20°C and shrimp densities 

 are discussed. The influence of salinity patterns, particularly with 

 respect to available nursery areas, is also presented. (A. A.) 



Keywords: shrimp production, nursery areas, estuaries, Louisiana 



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