Since I live in Portland and nobody has responded I will relate what little I know. First of all, I have never even seen the Siuslaw. The Wilson is a go to river For many drift boat and bankie gear fishers. Because, It is close to major metropolitan areas and get a fair number of hatchery keeper steelhead. Most of them return to the lower river since that’s where they were planted as smolts. I have never actually fly fished the river. The Wilson feeds into Tillamook bay, as do four other streams with winter steelhead runs. They aren’t fished as heavily because there are fewer keepers available. There are also a couple other rivers fairly close to the Wilson. A guided trip might be worth it. I can suggest a few if you are interested. I’ve also heard the Royal Treatment fly shop has done tours of the rivers in the area.
I prefer to swing flies for Steelhead myself so I don’t fish the coast much as I like big rivers with broad runs. However, if you like hiking and dead drifting smaller streams the the upper Wilson and other rivers in the area would provide lots of fishing opportunity, but maybe not catching... March is when the late run Natives enter, as well as their hatchery broodstock progeny. Historically, by March, the gear guys have moved on to spring salmon. But, with the broodstock program I’m sure it gets fished more heavily and probably by fly fishers too. Hope that helps, a little...
