From Portland Audubon:

“…an incredibly cool event that celebrates birds of prey that winter here in Portland. ... The event is a self-guided tour of four sites onSauvieIsland. … three wildlife viewing sites will be staffed with experienced naturalists and hawk experts, and an education site will feature raptor identification tips and live birds of prey. Participants pay $10 per vehicle, which includes a one-day Sauvie Island Wildlife Area parking permit, event guide, birding map and checklist, and illustrated handouts on how to identify birds of prey.” More info: http://audubonportland.org/local-birding/raptor2013