Kokanee lay eggs in shallow edges of lakes or in creeks, streams or
rivers. Salmon require gravelly soil and shallow water in order to make their
nests (redds) and lay eggs. They also need a specific water temperature at this time as they can only spawn in water with
temperatures from 4 to 13ºC. They hatch from their eggs into alevins. These small fish
then grow into fry. Fry have a main diet of plankton and use vegetation or the gravelly bottom of waterways for cover from predators. They eventually mature into parr and will then travel
into more open water where they mature into adults in three to five years (wildlife.utah.gov). In the open water, salmon chiefly feed on zooplankton, shrimp and
insects (Dill). The Lake Sammamish kokanee prefer the zooplankton Daphnia and it makes up the majority of their diet (Berge). They stay in the open water for an average of four years until spawning age is reached where they reach an average length of about 16-17 inches, and then they
return to their hatching place to spawn and die (Dill, Berge and Higgins).
(wildlife.utah.gov)
The life cycle of kokanee salmon; they will return to the same area that they hatched from to spawn and die.
Kokanee in Lake Sammamish
Historically, there are three possible stocks of kokanee in the Lake
Sammamish basin. There is the early, middle and late-run kokanee. Each run is
separated during spawning by their location and the timing of their spawning.
The early run kokanee spawn from early August to mid-September and have only been observed in Issaquah Creek. The middle run
kokanee spawn primarily in October and the late run kokanee spawn from late
October to early January. The late-run fry will then leave their tributaries from April until the end of May and travel into Lake Sammamish
(maps.google.com)
A satellite view of Lake Sammamish and the surrounding developed area.
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