The salmon run meets the river close to our house every year in late September till early October. Tumwater Falls park houses about 1500 Chinook Salmon each year... they take the eggs around the first of October and send them to the rivers that need Salmon repopluated.
This year we missed the biggest part of the run, but we did get to see a bunch of Salmon swimming around their tank, and we got to watch the few that were left jumping up the Salmon stairs make their way to where they lay eggs and pass on for the next generation to take over.
It takes them three to five years go to the sea and back again. I didn't realise it was that long... Ones that come back before they are mature are called Jacks. There are a few every year, but most come back when they are ready, like clock work... 3-5 years after they started their lives there.
Pretty neat if you ask me.