Salmon are sensitive to a variety of environmental factors. They can only survive in specific habitats and conditions; they are sensitive to the makeup of lake, river and stream bottoms, water temperature and quality, and plant and prey populations. Therefore they are able to serve as a sentinel species as to the quality of the environment for other species. However salmon are vulnerable to changes in water temperature in every stage of their life and small fluctuations can have substantial consequences on their numbers. The following pages will specifically focus on the kokanee salmon population in the Lake Sammamish Basin and how water temperatures can affect them.
Spawning age kokanee in Lewis Creek (kingcounty.gov)
Kokanee salmon are a landlocked form of sockeye salmon. This means that
they live their entire lives in lakes and may partially migrate to creeks,
streams or rivers to lay eggs but they do not migrate to the ocean. Kokanee are also called “blueback salmon” or
“silver trout” in their non-spawning stages and “red salmon” or “little
redfish” during their spawning stages (gotmyfishon.com).
(gotmyfishon.com)
Non-spawning compared to spawning forms of kokanee
Lake Sammamish is the sixth largest lake in Washington State with an average depth of 17.7m and a maximum depth of 32m. The tributaries to Lake Sammamish where kokanee have historically been recorded are Lewis, Ebright, Laughing Jacobs, Vasa, Pine Lake, Zaccuse, and Issaquah Creeks (kingcounty.gov). All of these tributaries feed into mid and south-Lake Sammamish.
(issaquahpress.com)
A map of Lake Sammamish tributaries where, historically, kokanee were found.
