Chinook Salmon - Distribution

Distribution

Historically, the native distribution of Chinook salmon ranged from as far south as the Ventura River in California and north to Alaska, as far as Kotzebue Sound. In China and the western Pacific, they are consistently present only in Kamchatka. Elsewhere, distribution is patchy, but occurs from northern Japan in the south to the Arctic Ocean as far as the East Siberian Sea and Palyavaam River in the north. Their populations have disappeared from large areas where they used to flourish, shrinking by as much as 40 percent. In North America, their inland range has been cut off, mainly by dams and habitat alterations, from Southern California, some areas east of the Coast Ranges of California and Oregon, and large areas in the Snake River and upper Columbia River drainage basins. Their distribution and presence in Russia is not fully known outside Kamchatka. They have a patchy presence in the Anadyr River basin and parts of the Chukchi Peninsula. In parts of northern Magadan Oblast near the Shelikhov Gulf and Penzhina Bay, stocks might persist, but they are poorly studied.

In 1967, the Michigan Department of Natural Resources planted Chinook in Lake Michigan and Lake Huron to control the alewife, an invasive species of nuisance fish from the Atlantic Ocean. Alewives then constituted 90% of the biota in these lakes. Coho salmon had been planted the year before and the program was a success. Chinook and Coho salmon thrived on the alewives and spawned in the lakes' tributaries. After this success, Chinook were planted in the other Great Lakes, where sport fishermen prize them for their aggressive behavior on the hook.

The species has also established itself in Patagonian waters in South America, where escaped hatchery fish have colonized rivers and established stable spawning runs. Chinook salmon have been found spawning in headwater reaches of the Rio Santa Cruz, apparently having migrated over 1,000 km (620 mi) from the ocean. The population is thought to be derived from a single stocking of juveniles in the lower river around 1930.

Sporadic efforts to introduce the fish to New Zealand waters in the late 1800s were largely failures and led to no evident establishments. Early ova were imported from the Baird hatchery of the McCloud River in California. Further efforts in the early 1900s were more successful and subsequently lead to the establishment of spawning runs in the rivers of Cantebury and North Otago; Rangitata River, the Opihi River, the Ashburton River, the Rakaia River, the Waimakariri River, the Hurunui River, and the Waiau River. The success of the latter introductions is thought to be partly attributable to the use of ova from autumn-run populations as opposed to ova from spring-run populations used in the first attempts. Whilst other salmon have also been introduced into New Zealand, only Chinook (or Quinnat as it is known locally in NZ) salmon have established sizeable pelagic runs.