Pink salmon

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Pink salmon

Pink salmon or humpback salmon

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Salmoniformes
Family:	Salmonidae
Genus:	Oncorhynchus
Species:	O. gorbuscha

Binomial name

Oncorhynchus gorbuscha
(Walbaum, 1792)

Pink salmon or humpback salmon (Oncorhynchus gorbuscha) (from the Russian gorbuscha--горбуша) is a species of anadromous fish in the salmon family. It is the smallest and most abundant of the Pacific salmon.

1 Appearance
2 Reproduction
3 Habitat
4 Commerce
5 References
6 Footnotes

[edit] Appearance

Pink salmon are bright silver fish when they live in the ocean, and their coloring changes to pale grey on the back with yellowish white belly when spawning. They have two dorsal fins including one adipose fin, dark coloration of the mouth and gums, large oval shaped black spots on the tail and back and 13-17 rays in their anal fins. The males develop a pronounced humped back during spawning, hence their nickname "humpies". Pink salmon are the smallest of the Pacific salmon with an average weight of five to six pounds and length of 30 inches.

[edit] Reproduction

Male at spawning time

Pink salmon in their natural range have a strict two year life cycle, thus odd- and even-year populations do not interbreed. Adult pink salmon enter spawning streams from the ocean, usually returning to the water course, or race, where they originated. Spawning occurs between late June and mid-October. Pink salmon spawn in coastal streams and some longer rivers, and may spawn in the intertidal zone or at the mouth of streams if hyporheic freshwater is available. The female fish lays her eggs in gravel and digs a trough-shaped nest called a redd with her tail. Once she has laid her eggs and they have been fertilized by the male's milt, she covers them. The female lays between 1000 to 2000 eggs in several clutches within the redd, often fertilized by different males. Females guard their redds until death, which comes within days after spawning. In dense populations a major source of mortality for embryos is superposition of redds by later-spawning fish. The eggs hatch from December to February depending on the water temperature, and the young emerge from the gravel during March and April and quickly migrate downstream to estuaries at about one-quarter gram. They return to freshwater in the summer or autumn of the following year as two year old adults. Pink and chum salmon can interbreed to form hybrid salmon in nature, but the hybrids are not fertile.

[edit] Habitat

Distribution and abundance of pink salmon in the United States

Adult pink salmon are cold-water fish with a preferred temperature range of 5.6 to 14.6 °C, an optimal temperature of 10.1 °C, and an upper lethal temperature of 25.8 °C. The pink salmon is native to Pacific and arctic coastal waters from the Sacramento River in northern California to the Mackenzie River in Canada; and to the west from the Lena River in Siberia to Korea. Populations in Asia occur as far south as Hondo Island in Japan. Pink salmon were introduced into the Great Lakes; this is the only location where the pink salmon have been successfully introduced into an entirely fresh water environment.

[edit] Commerce

The commercial harvest of pink salmon is a mainstay of fisheries of both the eastern and western North Pacific, over 100 million have been taken in recent annual harvests in Alaska alone.^[1] More than 20 million harvested pink salmon are produced by fishery-enhancement hatcheries, particularly in the northern Gulf of Alaska.^[2] Pink salmon are not grown in significant numbers in fish farms. The flesh is often canned, smoked or salted. Pink salmon roe is also produced commercially for caviar, a particularly valuable product in Asia.

Beginning in the late nineteenth century, fish traps were used to supply fish for commercial canning and salting. The industry expanded steadily until 1920. During the 1940s and 1950s, Pink Salmon populations declined drastically. Fish traps were prohibited in Alaska in 1959. Now most pink salmon are taken with purse seines and drift or set gillnets. Populations, and harvests, increased rapidly after the mid 1970s and have been at record high numbers since the 1980s.

Salmon Pink is a color, named for the colour of the flesh of pink salmon.