Your picture shows the feather as being almost totally brown instead of the nice rose-tan color of the Merganser flank feather. The Merganzer shoulder feathers are more the darker brown like the feather you pictured. The breast feather are a lot lighter and have a very definite pink coloration or cast to the feather.
I've never seen an orange parrot feather that had the bars on it that the feather Sean pictured has. Orange parrot feathers of this size are a solid color and come almost exclusively from Macaws. Flamingo feathers are both more feathery (they look like a light to hot pink heron feather) and flamingos do not live in the Seattle area either.