Way upstream on an east trib, in an area where I predominantly catch nice resident browns, and steelhead in Spring. Typical conditions for evening brown trout fishing, just after dark, tossing a worm under an undercut bank/log, was certain it was another brownie, nope, catfish.
Once fishing a marina/boat dock area for pike with spoons, got into a few steelhead (it was November).
Fishing the same marina with spoons, thought I had caught a fish, then saw it was a tree, reeled it in, turned out it was a section of a tree with a catfish stuck to it, the catfish had eaten a roe bag that someone had lost to the tree. I got the roe bag/hook out of the catfish and freed it.
Once I scoped out a pool in the middle of July, thought I found the mother of all resident trout holes as I stared at some humongous trout, turned out they were trapped steelhead, stuck in a giant pool and no where to escape.
A guy caught a laker in the slaughter pool on the Willy, I have also seen pike there in the fall.