I considered Gales Creek my home stream when I lived in Oregon. I've fished most of the public access water from the mouth to miles above the campground (hiking the banks and wading upstream.)
I've never had an encounter with any weird *people* on that stream - though I've found evidence more than once of people stealth camping or living out here (before the homeless situation in the whole area got bad) - but no BS - if you want an encounter with a Sasquatch, the upper reaches of that creek would be a good place to start.
As for the fishing - its surprising how large the fish will get in the "skinny" water up near the campground, and being that they opened it to year round angling, I found Winter to be a great time to fish up there. Water levels vary with rain, naturally but there's typically a lot more water in the winter than the summer (again, naturally) - but I've pulled some beautiful 12-15" cutthroats - huge for that stream in general - out of some skinny water barely deep enough to cover their backs.
The key with success on Gales Creek is your willingness to walk and wade - the places where there's a little trail to the water get hammered, and while you can still get a fish now and then, hike even a couple hundred yards away from the easy access points and you'll see gorgeous water and bigger fish.
Fly fishing was my go-to on that stream 90% of the time, but I also found that a light spinning rod with a box full of in-line spinners (Rooster Tails, Blue Fox, or my favorite Mepps) works great. For flies - fish what you like to fish - be it dry flies, nymphs, or streamers. My biggest fish on that stream came to appropriately sized streamers for the water, my second biggest came when I got into Euro-style nymphing. Gorgeous colored up cutthroat when the spawn was nearing ate a Prince Nymph a rod length away from me in water that was crystal clear and maybe 15" deep. I couldn't see the fish, it blended so well.
Summer time is also special to me in the upper reaches - wet wade with a 2 or 3 weight, a box of dry flies and wet flies, and just wade / hike through the stream, beating the summer heat. There are some really deep holes between ankle deep riffles and trickles even in summer, holes so deep that they're too deep for my 6'4" self to safely wade. Those holes held some really, really nice trout - and as a bonus to observe - occasionally you'll see steelhead or coho salmon make it up near the campground. You can't fish for them up there, but its really cool to watch them in such small water.
And I'm serious about the Bigfoot thing - you can call me crazy, but I've passed every psych exam I've ever taken (including two for licensing purposes in just the last year) - I had an encounter with one up about a mile and a half above the campground back in November of 2016 while I stopped to eat lunch during a fishing trip up there. It wasn't excitement filled at the time - I literally just turned my head when I got the feeling I was being watched, and there it was, not 30' from me. When I turned to look at it, he (very clearly a male) turned and bolted up the hill side, leaving muddy gouges in the hill side (sorry, no foot print pix because there were no good prints to take pix of) - I didn't feel scared like my life was in danger, but I did get a bit shaky after the realization set in, and I did call it an early day after that because I couldn't focus on the fishing.
Here's some pix I found from some outings up there at different times. My cousin Tyler (an inactive member here) used to fish with me quite often up there, and one of the pix is him with a nice trout he got on a nymph and the kind of water it came out of:
