Pikeminnow on flies?

I fish the oxbow lakes and sloughs down in the south part of the Willamette Valley (mostly after carp) and catch a lot of little pikeminnows. Just wondering if anyone else out there catches them on flies (or possibly even targets them on fly set ups) and if so what patterns and environments seem the most effective? Like I said, I catch a LOT of little ones but I'm looking to hook up with some bigger ones and have no idea where to start. For the most part I hook up to them using an 18-20 parachute adams with a pheasant tail under it with about a 6-9 foot leader and floating line (my go to rig for most occasions except when fishing deep) and am mostly wondering what environments and depths the big guys hang out in. Haven't been able to find much info about fishing for them with flies and even if I did manage to I definitely prefer local information. Thanks for your time and input,
Joffurson, I had to register just so I could respond to your post. Since last summer I have been spin fishing and fly fishing for smallmouth bass in the Willamette. I caught a ton of pikeminnow and enjoyed it. Whereas others look down on this fish, I say who wouldn't want to catch 30 or more aggressive fish that weigh up to 3 lbs? What you need to understand about pikeminnow is that they are predators and primarily eat minnows and smolt. You can catch larger ones on the edges of the main Willamette current and adjacent backwaters. In stained waters, strip a black leach pattern with big jerks, settling for a second in between. With clearer water use minnow streamers like sculpin imitations or clousers. Soon shad smolt will be present and they are typically towards the surface. Use white, silver, & black smolt pattern with small amount of weight and strip it just under the surface- strip, die, strip, die- explosive takes!

I am always fishing for smallmouth, but in some areas pikeminnow are so dominant that I either had to fish a heavily weighted fly to quickly get below the pikeminnow and imitate a crawfish instead of a bait fish, or resign myself to catch a bunch of pikeminnow, or move. I wish they had a bounty program on the Willamette, because I sure had them dialed in last summer! Have fun!