shrimp is of greatest importance to upper Gulf off the mouth of the Chao Phraya River . It is the major protein-yielding food source for the regional population. The yearly ‘sururu’ harvest, mostly by artisanal fishermen, is estimated at 5000 metric tons. After aprolonged period of low salinity in Mundaú lagoon, it takes several years for ‘sururu’ production to return to normal levels