Chum Salmon

Chum salmon in ocean coloration.
Photo: Washington Department of Fish and Wildlife

(Oncorhynchus keta)

Other names: Dog Salmon, Keta Salmon, Calico Salmon

Chum salmon in ocean coloration are metallic greenish-blue on the dorsal surface with fine black speckles making them difficult to distinguish from sockeye salmon. Chum salmon have fewer (19-26), shorter and heavier gill rakers on the first arch, relatively large eyes, a very narrow caudal peduncle (base of the tail), and deeply forked caudal fin. Chum salmon range in weight from 7-18 pounds and measure between 24-32 inches long. Male chum salmon spawning coloration includes an overall olive with vertical bars of darker green and purple, which provides the visual cue indicative of the common name, calico salmon. Spawning females generally sport a dark horizontal band along the lateral line and less intense green and purple vertical bars. The males develop the typical hooked snout of Pacific salmon and very large teeth which at least partly accounts for their other name of dog salmon.

 

Distinguishing features of chum salmon head and tail. Note the narrow caudal peduncle (left) and lack of spots.
Photos: Washington Department of Fish and Wildlife

Abundance, distribution, and natural history

482 total records (all life stages) exist and 82% provide spawning fish abundance estimates. Spawning chum salmon are documented among 43 unique streams in the park. Chum exhibit the widest distribution of any Pacific salmon species, spawning as far south as Monterey, California in the Eastern Pacific, east to the Mackenzie River on the Arctic coast of North America and as far as Korea in the Western Pacific. Most reports in Glacier Bay come from larger rivers such as the East Alsek, Dundas/Seclusion, and Excursion rivers. Chum salmon have been recorded spawning in streams in Glacier Bay between July and October. They generally prefer deeper, fast flowing water with larger gravel substrate commonly influenced by upwelling. Peak spawning fish abundance is evident in October but spawning activity varies among populations. When fry emerge from the gravel in the spring they migrate immediately to salt water, accounting for few juvenile records.

 

Female (top) and male (bottom) chum salmon in spawning colors.
Photo: Washington Department of Fish and Wildlife

Conservation measures and concerns

Little recreational and commercial fishing effort is currently directed towards this species. However, they were historically an important food source (dried for storage) for interior indigenous people along some of the larger Alaska rivers. Returning Excursion River fish comprise a culturally important subsistence seine fishery for the Hoonah Tlingit. The East Alsek River was once a productive chum fishery but few chum now return to this system likely due to changing habitat conditions and early (1951-1980) commercial, set gillnet harvests averaging around 10,500 fish annually.

 

Chum salmon gill rakers.
Illustration: US Forest Service Tongass National Forest

 

Relative (averaged across records) chum salmon run timing. Values in parenthesis indicate number of records for each month (total n = 395).