Saltwater Fish and Shellfish

In the murky sediment-saturated waters of the La Plata estuary, it can be difficult to spot any aquatic fauna, but it’s there in oceangoing fish species such as the yellow corvina and black corvina, as well as crustaceans such as crabs and shellfish such as mussels. Congrio (conger eel) and the overexploited merluza (hake) are among the top pelagic fish.

Shellfish and crustaceans include the relatively commonplace ostión (scallop) and calamares (squid).

Freshwater Fish

In the upper reaches of the Plata estuary, as far as the confluence of the Paraná and the Uruguay, freshwater game fish such as the boga, the dorado (a 30-kilogram fighter), sábalo, the 80-kilogram surubí (a giant catfish), and tararira mix with some of the oceanic species. These freshwater species, though, are abundant throughout the Mesopotamian provinces.

In the Andean region, introduced species include brook trout, European brown trout, rainbow trout, and landlocked Atlantic salmon. Native species (catch-and-release only) include perca bocona (big-mouthed perch), perca boca chica (small-mouthed perch), puyén, Patagonian pejerrey, and peladilla.

Marine Mammals

The most important aquatic mammal in the estuaries is the endangered La Plata river dolphin. The southern sea lion inhabits the coastline from the River Plate all the way south to Tierra del Fuego. From Chubut south, the southern elephant seal and southern fur seal are both on Appendix II of the Endangered Species List (CITES), classified as threatened or regionally endangered.

The most famous of Argentine whales is the southern right whale, which breeds in growing numbers in the sheltered waters around Península Valdés. Other cetaceans found in South Atlantic waters include the blue whale, the humpback whale, the fin whale, and the sei whale. The orca or killer whale is also present, along with smaller marine mammals such as Commerson’s dolphin.

© Wayne Bernhardson from Moon Argentina, 3rd edition