Most of the target species of the artisanal fishery in Patos Lagoon are marine species that use the estuary at a certain stage of their life cycle staying in the estuary for certain periods of the year, especially when they are adults. Mullet (M. platanus), for example, grows in weight as it moves from the ocean towards the inner areas of the estuary as their gonads mature. The present management of the estuary allows the species to be captured from October to May with drift or circling gillnets of 100 mm mesh size (stretched mesh). However, fishermen from the lower estuary catch them with 40–45 mm nets [4]. Adopting restricted fishing areas at different regions of the estuary,