The estuaries of this system are a deposit of stagnant water with a depth that varies between one and three meters covered by two types of aquatic plants: the ones that come from the bottom, forming places abounding in tall grass on the coast sides, or the floating formations that cover the water surface like pickerelweeds and embalsados. These ones sometimes have an important thickness.
 

The Esteros del Iberá (Ibera’s Estuaries) keep their level stable because of their capacity to retain rain water, due to the big quantity of vegetation of the place. According to the measurements, the rains, which annually fluctuate between 1200 and 1500 mm, give back to the system a quantity of liquid that is equivalent to the one that evaporates. A little less than a fourth part of the water received is derived to Paraná River, through Corrientes River, the only surface drainage of the system.
 

Corrientes’s Province government created the Iberá’s Natural Reserve on April 15th in 1983 by the law 3771. Up to this moment many villagers had lived directly or indirectly on the hunting of animals like alligator, deer, wolf or carpincho. The decision to preserve the area made the ancient hunters –called mariscadores- to be incorporated as park keepers, activity that was favored by the tourist potential of the zone.