Salmonids were first introduced to Argentinean Patagonia from the United States at the turn of the twentieth century with the goal of establishing feral populations for the development of recreational / sport fishing. Between 1904 and 1910 several consignments were shipped to this region containing embryos of brook trout (Salvelinus fontinalis), lake trout (S. namaycush) and landlocked salmon (Salmo salar sebago) from Canada, brown trout (Salmo trutta) and Atlantic salmon (Salmo salar) from England, France, Germany and Belgium, rainbow trout (Oncorhynchus mykiss) from the United States and Germany (introduced again from Denmark between 1950-1970) and Chinook (O. tshawytscha), sockeye (O. nerka) and coho (O. kisutch) salmon from the United States. By the 1930s, and until the 1970s, salmonid production in Argentina was centered at the Bariloche Hatchery in northern Patagonia, which became the main center of salmonid artificially rearing and propagation in Patagonia.

At present five salmonid species have established self-sustaining freshwater resident populations in several Patagonian basins; the most conspicuous and widely distributed are: the rainbow trout, the brown trout and the brook trout, whereas the landlocked Atlantic salmon and the lake trout have more restricted distributions, occurring in streams of Neuquén and Chubut Provinces and in Lake Argentino, Santa Cruz Province, respectively. On the other hand, anadromous species and populations of exotics salmonids are rare and limited to rainbow trout / steelhead, sea-run brown trout, and chinook salmon.

In Argentinean Patagonia, Chinook salmon spawn in the headwaters of several Pacific basins, such as Corcovado, Pico, and Futaleufú rivers in the Chubut Province. These populations are the result of escapes and straying from ocean ranching experiments and net-pen aquaculture in Chile. In the Santa Cruz province, there exists also a spawning population of Chinook salmon in the Caterina River, a small tributary of the upper Santa Cruz River Basin. This population is most likely the result of a recent colonization event (1980s) by straying fish from southern Chile via the Magellan Strait (the stocks used in ranching efforts in southern Chile were originally founded with Green River fish in Washington, USA). 

In the Santa Cruz River there is also an anadromous population of rainbow trout or steelhead. The source origin of this population, consisting of both anadromous and non-anadromous forms, traced back to early introductions to Patagonia (1900s) founded by Californian sotcks.

In the Gallegos (Santa Cruz Province) and Grande and Ewan (Tierra del Fuego Province) rivers there is sea-run brown trout, sustaining world renowned sport fisheries. Historical records indicate that this species was first introduced in the Santa Cruz Province by 1921 most likely from Germany. In Tierra del Fuego Province the origin of brown trout trace back to transplants made by the Bariloche Hatchery in the 1930s. In the following years brown trout introduced to the Grande River colonized several coastal and freshwater environments draining into the Magellan Strait and the South Atlantic Ocean.

In recent years, the sporadic occurrence of two anadromous species, Coho and Atlantinc salmon, has been reported for several coastal waters and freshwater basins of Southern Patagonia. Although these species have not yet established self-sustaining populations in Argentinean Patagonia, records of these fish in Atlantic waters grew paralleling the development of Chilean net-pen aquaculture.

Back