Species composition, relative abundance and distribution of macrocrustaceans and fishes in the intake area, discharge canal and cooling lake of the Cedar Bayou Electric Power Station at Baytown, Texas.

Species composition, relative abundance and distribution of macrocrustaceans and fishes in the intake area, discharge canal, and cooling lake of the Cedar Bayou Electric Power Station were examined once a month at 14-15 stations from January 1977 to July 1979. Hydrological data were concurrently sampled. The discharge canal had the highest temperatures. They ranged 1.5 - 14.5 C higher than the intake area temperatures. Water discharged into Trinity Bay, after passage through the cooling lake, at an average of 1.8 C higher than intake area temperatures. Salinity stratification was most apparent in the intake area. The salinity gradient of Cedar Bayou changed in October 1978, with station 1 becoming the saltiest rather than station 3, which historically had the highest salinities. Water quality in Cedar Bayou has been enhanced by the power plant operation. In 1969, the year prior to the plant's operation, 27 fishes were collected from Cedar Bayou. During my study, 60 fishes were caught in the intake area. That was the greatest variety found among the three areas, followed by the cooling lake with 50 fishes and the discharge canal with 20. The 10 most commonly collected species were: brown shrimp (Penaeus aztecus), white shrimp (P. setiferus), grass shrimp (Palaemonetes pugio), blue crab (Callinectes sapidus), Gulf menhaden (Brevoortia patronus), bay anchovy (Anchoa mitchilli), sea catfish (Arius felis), tidewater silverside (Menidia peninsulae), spot (Leiostomus xanthurus) and Atlantic croaker (Micropogon undulatus).