Evaluation of the Effects on Fin-Fish Populations of Opening the Port Mansfield Channel in the Lower Laguna Madre - Analysis of Populations of Sports and Commercial Fin-Fish and of Factors Which Affect These Populations in the Coastal Bays of Texas

The opening of Port Mansfield Pass appears to have increased the bay populations of pinfish, Lagodon rhomboides, in the summer, and anchovies, Ancho sp., in the winter. No relation was found between the opening of the pass and the abundance of grooved shrimp, Penaeus aztecus and P. durorarum. There was evidence that Port Mansfield Pass was used by adult southern flounder, Paralichthys lethostigma; adult redfish, Sciaenops ocellata; post-larval and juvenile penaeid shrimp; and by blue crabs, Callinectes sapidus, of all stages. A general decrease in the numbers of fish and shrimp in trawl samples was noted in 1963, probably due to large quantities of dead, wind-rowed vegetation at many of the stations and to high salinities in the Port Mansfield area. Port Mansfield Pass was ineffective in reducing or stabilizing salinities in the area.