Cynoscion arenarius is an estuarine dependent marine species with a wide distribution in the Campeche Sound. It shows a preference for depths of less than 70 m but is more abundant in zones of estuarine influence. Females mature between 152 and 170 mm TL. Reproduction occurs from February to April and July to September and spawning occurs in coastal zone areas influenced by estuarine processes at depths of less than 15 m. Juveniles enter the Terminos Lagoon and adjacent estuarine areas for protection, feeding and growth and later migrate to the Campeche Sound to mature and be recruited by the adult population. This recruitment takes place in June and November and is correlated with maximum abundance. It is a third order carnivorous consumer that feeds mainly on fish and secondly on crustaceans. There are differences in food size between juveniles and adults. The conditon of the population varíes with the reproductive dynamics and recruitment of juveniles. Energy is stored in the form of adipose tissue that is utilized to mature gonads or in migration. Males have a higher mortality per size while females reach a greater length. This species is efficiently caught at 200 mm TL.