Last Thursday morning, the day after I had the merlin fly-by, I got to actually see the merlin. He flew into the confer in my yard, called a while, flew out, flew by in again, and repeated that for about half an hour. I've heard him every day since but haven't gotten to see him again before today, when I learned that it is not just a single merlin, but a pair. I was just heading out for a tiny neighborhood walk when I heard one close by, and I looked up in time to see it fly into my confer. He called out the high-pitched, slightly ascending whinny I've been hearing, then in the distance another one answered him. There are several tall conifers in the neighborhood, and for almost my entire walk I could hear one of the merlins, and a couple times got to see one fly by. The way they move, it doesn't look like it should be physically possible to stay aloft. They're either soaring or, if they're flapping at all, it looks like they're only moving the very ends of their wings, like a human trying to fly by flapping his wrists. But they are, to their credit, flapping very fast.
These merlins seem to be a mated pair looking for a nest site. It would be pretty cool if they nested in the neighborhood, although they can choose a tree that is not mine, so that they don't eat all the smaller birds that come to my feeders.