Sockeye salmon (Oncorhynchus)
Sockeye salmon are blue-green on the back and top of the head, silver on the sides and white or silver on the belly. Immature sockeye salmon are iridescent in color, and juveniles, or smolts, develop black speckling called parr marks. The immature sockeye salmons body is slender, sleek and somewhat laterally compressed. Sockeye salmon are the slimmest and most streamlined of the Pacific salmon species and are swift swimmers.
They can be distinguished from the pink, coho and Chinook salmon by the absence of large, black spots. Chum salmon have larger and fewer gill rakers than the sockeye, which have 28 to 40 long and slender gill rakers on the first gill arch.
Sockeye salmon dine primarily on zooplankton in both fresh and salt water, but may also feed on insects, larval and small fishes, and squid.
Sockeye are found in the Pacific Ocean, the Columbia, Snake, Fraser, Nass, Stuart, and Skeena rivers, and the Redfish, Washington, Baker, Ozette, Quinault, and Wenatchee Lakes.
Sockeye salmon may migrate across the Bering Sea to areas close to Kamchatka, Russia, and south of the Aleutian Islands into the North Pacific Ocean. Sockeye also migrate eastward to the Gulf of Alaska.
In North America, sockeye salmon can be found in Alaska, British Columbia, California, Idaho, Montana, Nevada, Oregon, Washington and Wyoming.
Sockeye salmon are anadromous; they inhabit temperate coastal waters that are salt water and move to fresh water rivers and lakes to spawn. While in the ocean, salmon prefer water temperatures ranging from 39 to 53 F, which can affect the depth at which the salmon will be found in the water.
A variety of the sockeye, called kokanee, can be found year-round in freshwater lakes. The high temperatures and pollution within the lakes have required this landlocked sockeye to adapt and become more resiliant to poor water quality.
- The name sockeye salmon gets its origin from the First Nations of British Columbia who called the fish sukkai.
- The Latin name oncorhynchus nerka comes from the Greek words onkos and rhynchos, meaning hook and nose, and nerka, the Russian name for the species.
- There is no definitive information about salmon navigation, but some scientists hypothesize that salmon take magnetic cues from the earth and are led to the site of their own spawning by their olfactory senses.
- The kokanee salmon is a smaller, land-locked version of the sockeye.