As autumn approaches many outdoor adventurers enjoy watching a natural transformation that changes the look of Idaho’s high country; while the autumn sky is filled with the colors of changing leaves, so are many small Idaho streams filled with the color of spawning kokanee salmon. Kokanee are a land-locked version of the anadromous sockeye salmon which spend most of their adult lives in the ocean, then return to places like the Stanley Basin to spawn. The domesticated kokanee planted in Idaho reservoirs and lakes originated in Washington state in the 1930’s and 40’s. Fish and Game has successfully introduced them into many lakes and reservoirs around Idaho including: Lake Pend Oreille, Lake Coeur d’Alene, Priest Lake, Dworshak Reservoir, Payette Lake, Warm Lake, Lucky Peak, Arrowrock Reservoir, Anderson Ranch Reservoir, Deadwood Reservoir, Island Park Reservoir and Ririe Reservoir – just to name a few.
Kokanee can grow to 18 inches but the “typical” Idaho kokanee is 10 to 14 inches long. Many would argue they are the most flavorful freshwater fish found anywhere. However, that flavor is not nearly as pleasing when they start changing colors.
Kokanee spend much of their lives eating plankton and aquatic insects, following food sources in the water column. In spring and early summer they can be found in as little as five feet of water, but as temperatures warm in the summer, kokanee go as deep as 20 to 30 feet. Immature kokanee are silver to blue (hence the north Idaho name “blueback”) with a “football” shaped body. Like their salt water cousins the sockeye, their meat is pink to red and is highly prized for its rich flavor.
Kokanee reach maturity and spawn between the ages of 2 and 4 – depending on how fast they grow. When they prepare to spawn, their colors shift to a vibrant red with a green head. This transformation makes kokanee highly visible in streams and along shorelines – not only to people but to predatory birds. In north Idaho, large groups of bald eagles congregate to prey on the spawning fish. This provides wildlife watchers multiple opportunities to observe nature in action.
Early spawning Kokanee are visible in Mores Creek, the Middle Fork Boise, South Fork Boise and Deadwood River as early as Labor Day Weekend. Early spawners can also be seen in tributaries to Island Park, Palisades and Ririe Reservoirs in the South East Region. Spawning in north Idaho generally starts a few weeks later, and peaks around Thanksgiving. People in Boise can see spawning kokanee in the stream and through the glass at the MK Nature Center.