Life History Studies of the Commercial Oyster in the Lower Laguna Madre - Biological Survey of the Waters of the Laguna Madre of Cameron, Willacy, and the Southern Half of Kenedy Counties and Adjacent Waters

Studies on the six experimental oyster reefs in Port Isabel Bay show that the gulf oyster, Ostrea equestris, outproduces the commercial oyster, Crassostrea virginica, by more than 10 to 1 despite the seeding of all reefs. Encroachment on the reefs of manatee grass and brown alages contributes to the insignificant production of the commercial oyster and the high mortality of all spat. In South Bay commercial oyster production was slightly below normal, with considerably reduced harvest per unit of effort due to high mortalities caused by prolonged and extreme low tides and by siltation. A scarcity of cultch is also a factor limiting production.