Lake Sammamish Kokanee (Oncorhynchus nerka)

Thursday, May 24, 2012 at 03:04PM
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Great presentation last night by Robert Tabor and Jeff Chan, Fish Biologists with the US Fish & Wildlife Service, and WDFW Hatchery Operations Manager for Region 4, Doug Hatfield about the Lake Sammamish Kokanee program.

Historically, Lake Sammamish Kokanee (Oncorhynchus nerka) swam to lake streams by the thousands each fall and winter. This lake dwelling form of sockeye salmon provided subsistence food source to tribal communities, and angling opportunities to other Washingtonians.

Kokanee were found throughout the Lake Washington and Lake Sammamish basin. Today native kokanee are known to spawn in only four creeks of Lake Sammamish. Historically, kokanee spawned from August through January, representing two distinct run times. By 2001 the early run was extinguished and only the November to January late-run exists today.

In 2007 the Lake Sammamish Kokanee Work Group was formed. It is made up of representatives from local governments, Washington Department of Fish & Wildlife, US Fish & Wildlife Service, Tribal groups, conservation groups and concerned citizens. The group, through strategic habitat planning over the next ten years, will work to achieve the goal of preventing the extinction of this native fish population, and ultimately increase their abundance to a number capable of supporting kokanee fishing opportunities in Lake Sammamish.

Kokanee & Sockeye are the same species. Sockeye spend one year in the lakes then go to the ocean to grow before returning to the lake and their spawning streams. Kokanee spend their entire lives in the lakes, returning to their spawning streams when they are 3 to 5 years old. Kokanee and Sockeye are found around the edges of the Pacific Rim. We live in the southern edge of their range here in Puget Sound and they are much more prevalent in Alaska.

When kokanee hatch and emerge from their redd, they move immediately to the lake within the first 24 hours, preferably at night when they are less likely to be spotted by predators. Once in the lake they feed on zooplankton and larval yellow perch. To avoid predators in the lake they spend their days deep in the water where the temperatures are colder and less light penetrates. At dusk they come up to the top to feed and stay to feed again at dawn, going lower in the water in the day again.

What has caused the extinction of the summer and fall runs of the Lake Sammamish kokanee and threatened the winter run? Read our next post to learn more.