Chum salmon

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Chum salmon
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Actinopterygii Order: Salmoniformes Family: Salmonidae Genus: Oncorhynchus Species: O. keta
Binomial name
Oncorhynchus keta (Walbaum, 1792)

Keta redirects here. Keta can also refer to a character from the Myst Franchise.

The Chum salmon (Oncorhynchus keta) is a species of anadromous fish in the salmon family. It is a Pacific salmon and is also known as dog salmon or Keta salmon.

[edit] Appearance

They have an ocean coloration of silvery blue green.

[edit] Appearance at spawning time

Male chum salmon develop a very hooked jaw with large and fierce teeth and a humped back at spawning time. The coloration changes for spawning to splotchy purplish red and with distinct yellow and pink vertical bars on their sides. Color in the female is similar but not usually as distinct.

[edit] Spawning

Most Chum Salmon spawn in small streams and intertidal zones, especially among stalks of eelgrass. Some Chum travel more than 3,200 km (2,000 miles) up the Yukon River. Chum fry migrate out to sea from March through July, almost immediately after becoming free swimmers. They spend one to three years traveling long distances in the ocean. These are the last salmon to spawn (November to January). They die about two weeks after they return to the freshwater to spawn. They utilize the lower tributaries of the watershed, tend to build redds in shallow edges of the watercourse and at the tail end of deep pools. The female lays eggs in the redd, the male sprays sperm on the eggs, and the female covers the eggs with gravel. The female can lay up to 4000 eggs.

Chum Salmon of a breeding season.

[edit] Age

Chum can live from 3 to 6 years, and chum in Alaska mature at the age of 4 years.

[edit] Where they are found

The chum salmon is found in the north Pacific in the waters of Korea, Japan, and the Okhotsk and Bering seas (Kamchatka, Kuril Islands, Sakhalin, Khabarovsk Krai, Primorsky Krai), British Columbia in Canada, and from Alaska to San Diego in the United States.

Among the Southern Ewes along the coast of West Africa, mainly, Ghana, Togo and Benin anchovies are called "Keta Schoolboys" a reference to the fishing town of Keta, Ghana.

[edit] Sizes

Adult chum usually weigh from 4.4 to 6.6 kg, with an average length of 60 cm. The record for chum is 13 kg and 102 cm.

[edit] What they eat

Juvenile chum eat zooplankton and insects.

[edit] Commercial use and value

The chum salmon is the least commercially valuable salmon. They are so numerous at Alaska that commercial fishers are often kept from wanting to fish for them because of the low prices. Markets developed for chum from 1984 to 1994 in Japan and northern Europe which increased demand, though. They are a traditional source of dried salmon.

Artificially-incubated chum salmon

[edit] Conservation

In areas other than Alaska there are few groups of healthy chum remaining. This is partially because of dams, which block the free flow of the water and the migration of the fish.

[edit] Susceptibility to diseases

Chum are thought to be pretty resistant to whirling disease, but it is unclear.

[edit] See also

• Salmon
• Coho salmon
• Pink salmon
• Trout
• Chinook salmon

[edit] References

• Oncorhynchus keta (TSN 161976). Integrated Taxonomic Information System. Accessed on 24 January 2006.
• "Oncorhynchus keta". FishBase. Ed. Ranier Froese and Daniel Pauly. 10 2005 version. N.p.: FishBase, 2005.
• Encarta Encyclopedia 2004
• Alaska Department of Fish and Game