“Salmon Ranching” can be defined as the “artificial propagation of juvenile salmon for release into ocean basins”.
Salmon ranching may also be referred to as “ocean ranching”. Others may refer to it as “salmon enhancement”.
Simply put, salmon ranching refers to a process by which indigenous salmon are initially caught and stripped of eggs and milt. The fertilized eggs are then cultured in a hatchery where they will hatch and begin feeding on a feed powder. Mimicking the natural life cycle of a wild salmon, these salmon are then transported from freshwater hatcheries to saltwater fish farms. The juvenile salmon continued to be cultured in saltwater fish farms using net pens to contain the salmon. While in net pens, salmon are fed feed pellets to gain size and strength. Also, by remaining captive in an area suitable for a future commercial fishery, the salmon are “imprinted” to the area where they are temporarily farmed. Imprinting ensures that these cultured salmon return to the same place where they were “born” – similar to natural, wild salmon. Once large enough to successfully compete with wild salmon for food and space, these cultured salmon are released into the ocean to forage for food (referred to as “ranching”). Depending on the species of salmon (Pink, Chum, Coho, Chinook or Sockeye), they will return to their birthplace in two to four years. Upon return, a mixture of wild and ranched salmon are caught by commercial and sports salmon fisherman. Selected salmon are also retained by the source hatchery to be used again for eggs and milt – thus repeating the process.
In 2012, the Alaska Department of Fish and Game reported that 127 million salmon were commercially harvested. Of this, 44 million salmon were identified as ocean ranched. Therefore, in 2012, ocean ranched salmon represented over 34% of the commercial catch in Alaska.