[1] Prochilodus lineatus is considered the key species of the Paraná River, since it forms the base of the food chain that ends with larger fish like the surubí catfish (Pseudoplatystoma) and golden dorado (Salminus brasiliensis).

Regulations in place in Santa Fe and Entre Ríos, Argentina, have proven ineffective to preserve the species, which is being severely exploited, both for internal consumption and for export.

As the fish population dwindles, fishermen who depend on their captures for their livelihood are keeping smaller specimens, often not mature and which therefore have had no time to reproduce.

Widespread disregard of prescribed net sizes and the presence of illegal processing plants, which the local governments do not control, have compelled environmental groups to protest.

On August 1, after Entre Ríos matched its regulations with those of Santa Fe, 300 fishermen and freezing plant workers from Victoria did the same.

In October 2006, largely to facilitate the reproduction of sábalo, the legislative branch of Santa Fe attempted to pass a temporary ban on commercial fishing in the Paraná.