Sockeye

Description

Sockeye are commonly known as “red” salmon, especially in Alaska, due to the bright reddening (especially in males) of the body when adults return to spawn in freshwater. During this transformation the head becomes greenish, with hooking of the jaws especially in males and a small dorsal hump in males (much less pronounced than in male pink salmon). Before developing their spawning colors, ocean sockeye have a greenish-blue hue (blueback salmon) with fine black speckles on their backs. They can reach up to 33 inches and weigh up to 15 pounds, although on average they typically weigh between 5 and 8 pounds.

In Whatcom County

Because there is no suitable lake associated with the Nooksack River, there are no “lacustrine sockeye” in the watershed. There are small numbers of riverine sockeye in two Nooksack River populations; one in the North/Middle Fork and one in the South Fork. Lacustrine sockeye are present in the county’s Baker Lake, where adults trapped from the Baker River are transported for release into the lake, hatchery production, or spawning channels.

Range

Columbia River northward to the Bering Sea’s Bristol Bay (greatest abundance is from Bristol Bay south to the Fraser River) and along the east coast of Asia, with most abundance in the Sea of Okhotsk and the Kamchatka Peninsula.

Life History

Nearly all sockeye populations are “lacustrine,” meaning the life cycle depends on a period of juvenile rearing in a lake. Lacustrine sockeye spawn in a lake’s tributary streams, its outflow stream, or along the lake’s shore, and juveniles rear for one to two years in the lake before the smolts migrate to the ocean. Riverine populations spawn in a river and the juveniles rear in the river before migrating to the ocean, usually after a few months in freshwater.

Spawning Season

August to October.

Habitat Requirements

Sockeye require the same needs as other salmon: cool, clean, well-oxygenated water and clean gravel of appropriate size and depth. Those spawning along a lake shore require ground water upwelling through the gravel for the incubating eggs and alevins. Once in the lake, the juveniles require sufficient production of zooplankton for growth.

Did You Know

The kokanee of Lake Whatcom, Lake Padden and Lake Samish are non-anadromous sockeye that complete their life cycle entirely in freshwater. Sockeye are mainly filter feeders, and their red flesh and body color when spawning comes from carotenoids consumed in their ocean-rich diet of krill. The name sockeye is from a translation of the Salish word “Suk-kegh,” meaning red fish. Sockeye is the third most abundant species of Pacific salmon.

Illustrations: Pacific Salmon, Childerhose & Trim (Douglas & McIntyre, Vancouver/Toronto).