Good question...

...but I would expand its scope a bit and ask why steelhead strike many of the things they do strike?

A worm probably looks a lot more like something that actually could be "alive" than many other lures that have been catching fish for decades.

Let's see: big chartreuse/orange spin-n-glos, day-glo plugs of all types, glo balls, etc. the list goes on and on.

You might even ask why steelhead respond to bait, since the majority of the time they aren't going to actually eat it!

I think they hit worms for the same reasons they hit the other stuff...and there remain on-going arguements about that too. Basically, to catch fish a lure need not "represent" anything in particular. It just has to trigger a strike based on some combination of latent feeding instinct, territoriality, aggression, curiousity, or other factors we may not even realize.

And that is what helps make steelhead such a special fish!
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