A study of Texas shrimp populations, 1975




Johnson, Roy B., Jr.

Journal Title

Journal ISSN

Volume Title


Texas Parks and Wildlife Department


During April-May 1975 brown shrimp (Penaeus aztecus) were sampled with bar seines and otter trawls at designated stations in Galveston, Matagorda, Aransas and Lower Laguna Madre Bays to determine shrimp growth rates and time of bay-to-Gulf migration. Although small groups of brown shrimp emigrated from Aransas Bay to Lower Laguna Madre in April and May, the mass migration of shrimp was late. The 1 June starting date of the closed Gulf season was retained. Estimated growth rates were 1.5 mm per day in Galveston and Matagorda Bays and 0.9-1.1 mm per day in Laguna Madre. During June-October 1975 white shrimp (P. setiferus) and brown shrimp were sampled with otter trawls to determine percentages of legal size shrimp on commercial shrimping grounds of Galveston, Matagorda and Aransas Bays. These percentages were fairly high (16-67%) near the 15 August opening of the bay season, and more than 10% were legal size through October. In Galveston Bay samples collected in late November and December contained less than 1% legal size shrimp. During 1973-75 less than 22.7 million kg of brown and white shrimp (heads-off) were landed annually at Texas ports, compared with the record 28.1 million kg in 1967. In 1975 financial problems with the shrimp industry and low shrimp densities contributed to low landings. Floods lowered the salinity to less than 5 o/oo in parts of Matagorda and Galveston Bays during April-May, reducing the amount of nursery area available to brown shrimp on the upper coast.


pgs. 1-35


shrimp fisheries, penaeid shrimp, brown shrimp, Penaeus aztecus, white shrimp, Penaeus setiferus, trawl nets, migrations, catch statistics