Last Friday evening, May 3 @7p, vicinity Hwy 99 W x McDonald, Tigard. I looked well overhead and spotted 3 huge all white birds beating NE into the headwind we had that day. They continued without much deviation past 217 toward Metzger and beyond. Beautiful sight. I ran through all the big white birds we could have around here now and eliminated all but swans, either Tundra or Trumpeter (I thought Mute most improbable). Of the two I favored Trumpeter because of my impression of size. The recent reports on OBOL of Trumpeters at the mid-valley refuges about that time fit with that ID.