An ecological survey of the Houston ship channel and adjacent bays

AN ECOLOGICAL SURVEY WAS INITIATED IN THE SUMMER OF 1957 WITH DATA COLLECTED AT FREQUENT REGULAR INTERVALS. THIS REPORT INCLUDES THE COMPARISON OF DATA ON TEMPERATURE, CHLORINITY, DISSOLVED OXYGEN, AND RELATED QUANTITIES WITH DATA ON FISH, SHRIMP, AND CR IN TRAWLS. DATA ARE ALSO GIVEN ON CURRENTS, BOTTOM CORES, AND ORGANIC CONTENT OF SEDIMENTS. STUDIES OF BOTTOM SAMPLES DEMONSTRATED THAT EXTENSIVE SILTING HAS OCCURRED IN THE SHIP CHANNEL AND BAYS. LOW DISSOLVED OXYGEN, HYDROGEN SULFIDE PRODUCTION, AND HIGH ORGANIC CONTENT OF THE MUD IN THE CHANNEL, ALL INDICATIVE OF ORGANIC POLLUTION, PREVENT THE EST A NORMAL BOTTOM FAUNA. A SMALL TEMPERATURE GRADIENT WAS FOUND IN THE SHIP CHANNEL, TWO OR THREE DEGREES HIGHER IN THE UPPER CHANNEL THAN IN THE LOWER PART OF THE SURVEY AREA. WHEN DISSOLVED OXYGEN (D.O.) LEVEL IS SUFFICIENT, A LARGE AND DIVERSE POPULATION OF FISHES EXISTS THROUGHOUT THE BAYS IN THE SURVEY AREA AND FOR A CONSIDER OUTFALL. NO LOWERING OF THE DISSOLVED OXYGEN CONCENTRATION OF THE SHIP CHANNEL ATTRIBUT EFFECT WAS FOUND TO BE EXERTED ON THE FISH POPULATIONS OF THE SHIP CHANNEL AND ADJACENT BAYS BY HUMBLE'S OPERATIONS