The long Paraná River has only 50 percent of the fish in its course through Argentina that it had 20 years ago due to over-exploitation, warns the Institute of Technological Development at the Littoral University. Twenty percent of the 220 fish species of the Paraná are of high commercial value, such as the ‘sábalo’ (shad), with Argentina producing 30,000 tons annually, exporting to Brazil, Bolivia, Colombia, Nigeria and Paraguay.

The extinction of that species would lead to the disappearance of other species, such as the ‘dorado’ and the ‘surubí’, which feed on shad.