Kokanee Salmon

Kokanee salmon are a landlocked, non-anadromous form of sockeye salmon (Oncorhynchus nerka) that complete their entire life cycle in freshwater rather than migrating to the ocean. Populations occur naturally in some lakes across the Pacific Northwest of North America and parts of Russia and Japan, and have been widely introduced into reservoirs and lakes elsewhere for fisheries. Despite being the same species as ocean-going sockeye, kokanee are typically smaller due to the more limited food resources available in freshwater lakes compared to the ocean. They are an important prey and forage species in the lake ecosystems they inhabit.

Kokanee salmon are identified by their small size and sockeye-like features:

• Slender, torpedo-shaped body, silvery-blue for most of the year with no large black spots
• At spawning, body turns bright red and the head turns olive-green, closely resembling spawning sockeye but on a smaller scale
• Small adipose fin, deeply forked tail, and numerous fine gill rakers used for filtering plankton
• Typically 23-30 cm long, considerably smaller than sea-run sockeye of the same species
• Males develop a hooked jaw (kype) and humped back during the spawning season

Kokanee live exclusively in freshwater lakes and their connected tributary streams, never migrating to the ocean despite being genetically identical to anadromous sockeye salmon. They favor cold, deep, oxygen-rich lakes across western North America, with introduced populations established in reservoirs and lakes across the continent, as well as naturally occurring populations in parts of Russia and Japan. Juveniles and adults spend most of the year in open lake water, feeding on plankton, before moving into shallow tributary streams or lake shorelines with gravel substrate to spawn in autumn.

Kokanee are schooling fish that spend most of the year in open lake water, feeding on zooplankton filtered through fine gill rakers, much like their sea-going sockeye relatives. In autumn, mature adults undergo a dramatic spawning migration into tributary streams or gravel lake shorelines, where they develop bright red coloration and, in males, a hooked jaw and humped back. Like all Pacific salmon, kokanee are semelparous, meaning they die shortly after spawning. Their annual die-off delivers nutrients into stream and lake ecosystems, supporting invertebrates, birds, and other wildlife, while providing an important forage base for larger predatory fish.