It depends on the type of Salmon. The Pacific Salmon dies after spawning upstream. The Atlantic Salmon goes back to the ocean.
Oncorhynchus is a genus of fish in the family Salmonidae; it contains the Pacific salmons and Pacific trouts. The name of the genus is derived from the Greek onkos ("hook") and rynchos ("nose"), in reference to the hooked jaws of males in the mating season (the "kype").
The Atlantic salmon, Salmo salar, is a fish in the family Salmonidae, which is found in the northern Atlantic Ocean and in rivers that flow into the north Atlantic and, due to human introduction, the north Pacific.
It is also commercially known as bay salmon, black salmon, caplin-scull salmon, fiddler, grilse, grilt, kelt, landlocked salmon, ouananiche, outside salmon, parr, Sebago salmon, silver salmon, slink, smolt, spring salmon, or winnish.
Aquaculture of salmon
The salmon run is the time when salmon, which have migrated from the ocean, swim to the upper reaches of rivers where they spawn on gravel beds. After spawning, all Pacific salmon and most Atlantic salmon die, and the salmon life cycle starts over again. The annual run can be a major event for grizzly bears, bald eagles and sport fishermen.
Salmon spend their early life in rivers, and then swim out to sea where they live their adult lives and gain most of their body mass. When they have matured, they return to the rivers to spawn. Usually they return with uncanny precision to the natal river where they were born, and even to the very spawning ground of their birth. It is thought that, when they are in the ocean, they use magnetoception to locate the general position of their natal river, and once close to the river, that they use their sense of smell to home in on the river entrance and even their natal spawning ground.
Salmon, along with carp, are the two most important fish groups in aquaculture. In 2007, the aquaculture of salmon and salmon trout was worth US$10.7 billion. The most commonly farmed salmon is the Atlantic salmon. Other commonly farmed fish groups include tilapia, catfish, sea bass, bream and trout.
Salmon aquaculture production grew over ten-fold during the 25 years from 1982 to 2007. Leading producers of farmed salmon are Norway with 33 percent, Chile with 31 percent, and other European producers with 19 percent.