It's still a tad early to primarily target bluebacks, on the Siletz at least. Lots of summer steelhead in the gorge though. The Bluebacks typically run late summer through early fall when the blackberries are in full force. I'm 100% sure there's a few in the Siletz right now but probably few and far between. You're best bet is to start lower (town of Siletz holes and holes along hwy 229) but it wouldn't hurt to drive up the gorge on a weekend and toss a line. I grew up in Siletz and have spent more days on this river than any other body of water; my suggestions would be Panther Martin Spinners, Worms, Crawdad tails, Borden Special flies, and other small spinner varieties. I can PM you my phone number if need be
-Siletz Trout Killer