The chum salmon (Oncorhynchus keta) is a species of anadromous fish in the salmon family. It is a Pacific salmon, and may also be known as dog salmon or keta salmon, and is often marketed under the name silverbrite salmon. The name chum salmon comes from the Chinook Jargon term tzum, meaning "spotted" or "marked", while keta in the scientific name comes from the Evenki language of Eastern Siberia via Russian.
|Scientific classification |
|Nutritional value per 100 g (3.5 oz)|
|Energy||502 kJ (120 kcal)|
|Dietary fiber||0 g|
|Aspartic acid||2.062 g|
|Glutamic acid||3.006 g|
|Vitamin A equiv.|
|Pantothenic acid (B5)|
|Alcohol (ethanol)||0 g|
|†Percentages are roughly approximated using US recommendations for adults. |
Source: USDA Nutrient Database
The body of the chum salmon is deeper than most salmonid species. In common with other species found in the Pacific, the anal fin has 12 to 20 rays, compared with a maximum of 12 in European species. Chum have an ocean coloration of silvery blue green with some indistinct spotting in a darker shade, and a rather paler belly. When they move into fresh water the color changes to dark olive green and the belly color deepens. When adults are near spawning, they have purple blotchy streaks near the caudal peduncle, darker towards the tail. Spawning males typically grow an elongated snout or kype, their lower fins become tipped with white and they have enlarged teeth. Some researchers speculate these characteristics are used to compete for mates.
Most chum salmon spawn in small streams and intertidal zones. Some chum travel more than 3,200 km (2,000 mi) 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 very long distances in the ocean. These are the last salmon to spawn (November to January) in some regions. In Alaska they are the first to spawn in June and August and are then followed by pink and coho salmon. They die about two weeks after they return to the freshwater to spawn. They utilize the lower tributaries of the watershed, tend to build nests called redds, really little more than protected depressions in the gravel, in shallow edges of the watercourse and at the tail end of deep pools. The female lays eggs in the redd, the male sprays milt on the eggs, and the female covers the eggs with gravel. The female can lay up to 4000 eggs.
Chum live for an average of 3 to 5 years, and chum in Alaska mature at the age of 5 years.
Adult chum usually weigh from 4.4 to 10.0 kg (9.7 to 22.0 lb) with an average length of 60 cm (24 in). The record for chum is 19 kg (42 lb) and 112 cm (44 in) and was caught at Edie Pass in British Columbia.
Chum salmon have the largest natural range of any Pacific salmon, and undergo the longest migrations within the genus Oncorhynchus, far up the Yukon River and deep into the Amur River basin in Asia. In lesser numbers they migrate thousands of kilometres up the Mackenzie River. Chum are found around the north Pacific, in the waters of Korea, Japan, and the Okhotsk and Bering seas (Kamchatka, Chukotka, Kuril Islands, Sakhalin, Khabarovsk Krai, Primorsky Krai), British Columbia in Canada, and from Alaska to California in the United States. In the Arctic Ocean they are found in limited numbers from the Laptev Sea to the Beaufort Sea. In North America chum salmon spawn from the Mackenzie River in the Arctic to as far south as Tillamook Bay, Oregon, although they were also reported in the San Lorenzo River near Santa Cruz, California in 1915 and the Sacramento River in northern California in the 1950s. In fall 2017 a half dozen chum salmon were counted in Lagunitas Creek about 25 miles (40 km) north of San Francisco, California.
In the open ocean chum salmon stay fairly high on the water column, rarely diving below 50 meters. Their typical swimming depths are 13 meters from the surface during the day, and 5 meters during the night.
Commercial use and value
The registered total harvest of the chum salmon in the North Pacific in 2010 was some 313,000 tons, corresponding to 91 million fish. Half of the catch was from Japan, and about a quarter each from Russia and the United States. The chum salmon harvest was about 34% of the total harvest of all Pacific salmon species by weight.
The chum salmon is the least commercially valuable salmon in North America. Despite being extremely plentiful in Alaska, commercial fishers often choose not to fish for them because of their low market value. Recent market developments have increased the demand for chum salmon. Markets developed for chum from 1984 to 1994 in Japan and northern Europe which increased demand. They are a traditional source of dried salmon.
Susceptibility to diseases
Chum are thought to be fairly resistant to whirling disease, but it is unclear.
|Wikimedia Commons has media related to Oncorhynchus keta.|
- "Chum salmon: Oncorhynchus keta (Walbaum)". NatureGate. Retrieved 2013-12-16.
- Augerot, Xanthippe; Foley, Dana Nadel (2005). Atlas of Pacific salmon: the first map-based status assessment of salmon in the North Pacific. University of California Press. pp. 68–71. ISBN 978-0-520-24504-4.
- J.R. Irvine, E. Linn, K. Gillespie, C. McLeod, and J.D. Reist (March 2009). Pacific Salmon in Canada’s Arctic Draining Rivers, With Emphasis on Those in British Columbia and the Yukon (PDF) (Report). Pacific Fisheries Resource Conservation Council. Retrieved December 30, 2017.CS1 maint: uses authors parameter (link)
- N. B. Scofield (1916). "The humpback and dog salmon taken in San Lorenzo River". California Fish and Game. 2 (1): 41.
- Richard J. Hallock and Donald H. Fry, Jr. "Five Species of Salmon, Oncorhynchus, in the Sacramento River, California". California Fish and Game. 53 (1): 5~22. Retrieved December 29, 2017.CS1 maint: uses authors parameter (link)
- Tiffany Camhi (December 9, 2017). "Marin's Lagunitas Creek Welcomes Unexpected Guests in this Year's Spawning Season". KQED News California Report. Retrieved December 29, 2017.
- Ishida, Yukimasa (2001). "Vertical movement of a chum salmon Oncorhynchus keta in the western North Pacific Ocean as determined by a depth-recording archival tag". Fisheries Science. 67: 1030–1035.
- Annual Statistics 2010: Commercial salmon catch by species and country North Pacific Anadromous Fish Commission Statistical Yearbook. Retrieved March 16, 2015. The numbers do not include fish taken in Russian waters by non-Russian fleet.
- "5-Year Review: Summary & Evaluation of Lower Columbia River Chinook, Columbia River Chum, Lower Columbia River Coho, Lower Columbia River Steelhead" (PDF). National Oceanic and Atmospheric Administration. 2011. Retrieved 2013-12-03.
- "5-Year Review: Summary & Evaluation of Puget Sound Chinook, Hood Canal Summer Chum, Puget Sound Steelhead" (PDF). National Oceanic and Atmospheric Administration. 2011. Retrieved 2013-12-03.
- National Marine Fisheries Service chum salmon web page
- Froese, Rainer and Pauly, Daniel, eds. (2005). "Oncorhynchus keta" in FishBase. 10 2005 version.
- Alaska Department of Fish and Game
- National Marine Fisheries Service ESA Listings