Beaver1,
It's legal to hunt ducks on the Clack, you just have to be very very careful about where. Obviously when there is a lot of boat traffic or you're near houses you can't do it. The Clack can offer some decent duck hunting, usually in low water years. The river always holds water so when the fields aren't flooded and the ponds are low, the river has some birds. I've killed most of the major species on or around it. Mallards make up 95% of my bag (unless you want to count merganzers). I've also gotten woodies, gadwall, shovelers, ringneck, teal, wigeon, redheads and scaup in the past. Depends what the storms bring in off the Columbia. Sometimes you get into the geese but usually they are flying high or in the fields. The key to drift hunting the Clackamas is access. Most of the good hunting is not right on the river. You'll get some pass shooting in if the birds are flying and you're in a good spot, but the best places are along the river on private land. There are some ponds, sloughs and creeks I hunt and get the majority of my birds. I've been hunting the Clack for a long time and know virtually all of the spots you can go and have permission to hunt them. If you can get access, more power to ya. You'll do much better. I don't want to give away all my secrets, but hopefully that is some helpful information.
There should be some of the pics on here that Lured In was talking about, if you're interested.
http://www.picturetrail.com/gallery/...ame=birdhunter