I've answered my own question. The fifth one is a Black Oystercatcher, the west coast version. I'm only familiar with the east coast version, called the American Oystercatcher, which has a good bit of white on the undersides.
I've been that close to Harlequins only once, on a mountain stream in Iceland many years ago. Wood ducks I have seen have always been too far away to get a good photo, so it is a treat to see these wonderful images.
A week or so ago I had a Brown Creeper on one of my bird feeders for about a second. That was a first in my yard.