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Coho Salmon

Common Name: Coho Salmon, silver salmon.
Scientific Name: Oncorhynchus kisutch (Walbaum 1792)

How to Identify a Coho Salmon:
  • Coho Salmon have spots on the back and spots on the upper half of the tail. 
  • Coho Salmon are extremely rare in the Canadian Arctic (only 1 has been reported to date). 

What do they look like?
In the ocean, the body of a Coho Salmon is streamlined and silvery in colour with black spots on the back and upper sides, and black spots on the upper half of the tail.  When Coho Salmon return to the freshwater to spawn, they become darker and the males develop a red horizontal stripe on their side.  Spawning Coho Salmon also have extended, hooked snouts and barred teeth, but less so than the other species of salmon.  The appearance of males changes more than that of the females while in freshwater.
  
                                            Coho Salmon male in spawning colours.
 
How do they live (what is their life-cycle)?
Coho Salmon adults return to freshwater rivers to spawn, and often return to the freshwater river where they were "born".  Coho Salmon migrate upstream and seek spawning locations in gravel near or in a lake where the water flowing through the gravel never freezes, even in winter.  The eggs and milt (sperm) are deposited in a depression dug in the gravel.  After spawning, the adults die.  The eggs develop over the winter and the fry emerge from the gravel in the spring.  Coho Salmon juveniles spend 1-2 years in the river or a lake before going to the ocean.  Coho Salmon spend 1-2 years in the ocean before returning to spawn as adults.  

What do they do?
Much of the biology of salmon in the Arctic is not yet known, and is being discovered with this research.  Coho Salmon spawning locations are not known in the Canadian Arctic.

Where do they go?
Coho Salmon range from the Russia to Korea in the western Pacific and from Point Hope, Alaska to California in the eastern Pacific.  Stray Coho Salmon have been reported from Point Hope east to Prudhoe Bay, Alaska.  Coho Salmon are the rarest of all Pacific Salmon in the Canadian Arctic; only 1 capture has been recorded.  One Coho Salmon was captured at Great Bear Lake in 1987. Coho Salmon Spawning has not been recorded in the Canadian western Arctic.

Map showing catch locations of all coho salmon captured and turned into Fisheries and Ocean Canada from
            2000-2011.  Map produced by the GIS Department, Aurora Research Institute.