It was introduced from Europe into most of the Patagonian basins. Nonetheless, it has not become adapted to so many environments as the rainbow. This is the trout that grows to the largest sizes. In Lake Nahuel Huapi, a specimen weighing 16,300 kg was caught. Its embalmed body may be observed in the facilities of the Nahuel Huapi Fishing and Hunting Association. Seven world records have been confirmed about a variety that migrates to the sea, which have positioned this river as the second most interesting river for salmon fishing in the world. This species has a characteristic golden color; its dorsal part is brown with silver sides and a yellowish abdomen. It has orangish spots on its sides and very notorious dark spots with a slightly lighter shade on the sides, up to the area beneath the side line, the back and the opercula. The adipose fin may have many spots but they are generally sparse and located on the upper lobe.
Its diet is varied and it gives evidence of great voracity, hunting creatures such as invertabrates, fish and even small rodents.
This is the most distributed trout in Patagonia, due to its high capacity of becoming adapted to various environmental conditions.
There is even one variety in the Santa Cruz River that has developed a very particular anodromous behavior, migrating to the sea several times in its lifetime in search for food, thus reaching interesting sizes. The rainbow trout stands out from the rest of the salmonidae due to the broad purple band on each of its sides, from its operculum to its tail. Its back is olive oil and its sides are silver colored, turning white in its abdomen. It presents round black marks almost all through its body, mainly on the back. The dorsal and caudal fins are profusely spotted. The anal fin may feature an outer white border in the trout dwelling in creeks.
The trout dwelling in the lakes, especially those close to glaciers, adopt a darker color on the back; have silver sides and white abdomen.
Its diet is quite varied but it feeds mainly on invertebrates.
This is the most eye-catching trout due to its remarkable colors. Its back is olive oil with greenish yellow spots. The pectoral, pelvic, anal and caudal fins feature a white end with a black border and there are red spots on its sides, generally surrounded by a blue aureola. During the reproduction season, many specimens feature a strongly orange shade, sometimes with yellow spots. The body is covered with scales much smaller than in other salmonidae dwelling in Patagonian waters.
This is the smallest Patagonian salmonidae. It dwells in the coldest waters and it is usual to find them in underground water springs. However, in richer environments, such as some lakes in Chubut, it is normal to find specimens weighing over 4 kg. It feeds on snails and a wide range of invertebrates living in the creeks or accidentally falling into the water.
It was introduced in many Patagonian lakes and rivers; however, it only developed in self-sustained populations in the basins of Lake Argentino and Lake Burmeister. This is a predator fish with stressed cannibalism. It is generally thin, with disproportionaly large head with respect to its body. That is why the locals call it “cabezona” (big head). It can grow to very large sizes. It sometimes can weigh over 20 kg. It is less aggressive than the other trout; therefore, it represents a good prize for sport fishermen. It hybridises with brook trout in deep waters, regardless of any water course.
Los salmones del Pacífico (género Oncorhynchus) son originarios del Pacífico Norte, en una amplia zona de distribución que se extiende a las dos costas oceánicas. A partir de una intensa actividad de piscicultura en Chile, e intentos de desarrollar una pesquería comercial a través de técnicas de sea ranching, a mediados de los 80 comenzaron a aparecer en las cuencas que vierten hacia el Pacífico (Río Pico, Río Corcovado, Lago Pueyrredón, Río Puelo y Río Futaleufú) salmones de la especie Chinook Oncorhynchus tshawytscha y Coho Oncorhynchus kisutch.
Los salmones del pacífico tienen una característica que los diferencia y es su condición de semélparos, es decir que mueren después de reproducirse, lo que provoca una alta incorporación de materia orgánica a través de sus restos, sin estar preparado los ecosistemas para asimilarla. También presentan un comportamiento agresivo como reproductores al momento de sucederse las luchas el predominio de los machos y también de los juveniles luego de emerger de los nidos de desove hasta su migración al mar. No obstante, sus altas tasas de crecimiento producto de su vida oceánica, los hacen muy atractivos cuando el objeto de la pesca es la búsqueda de trofeos.