I've birded the last 2 days in Arizona with Stuart Healy, one of the more experienced guides in SE Arizona. I've never used a guide in the U.S. before so it's definitely been an interesting experience. The bottom line is that if you want to find that last 5-10% of the birds in an area, you either need a lot of time, or specialized knowledge. Lacking much time, I decided to invest, and was not disappointed.
We started this morning near Patagonia attempting to hear the long-staying Sinaloa Wren. We'd heard that yesterday it sang loudly for the first time in quite a while in the pre-dawn. Unfortunately it was much quieter today, it apparently gave one half-snippet of song which a cardinal walked all over and I didn't come close to hearing. We gave up after a little over an hour and headed about an hour and a half north and west to Florida Canyon in the Santa Ritas where rufous-capped warblers have been seen. When we arrived about a dozen birders were spread out along the section of trail where they'd been seen. We waited maybe 15 minutes before Stuart heard the bird singing from the far slope, the only one of the assembled to pick up on it. The bird popped up and I had good views through the scope of this distinctive chat-like bird. On our way down we ran into black-capped gnatcatchers, a species I had hoped we could find since I don't know that I could comfortably separate a female black-capped from the very similar female blue-gray. As it was there was a pair which made it much easier, though I had scope views of both birds. Since we'd saved ourselves from having to go back to Patagonia for more reliable black-cappeds, we headed back to the Huachucas to Scheelite Canyon to look for these:
As you can see, it helps to know what you're looking for. If you havn't found the bird yet look dead center and on the dark branch angling across the center is (at least the lower parts of) a spotted owl. Stuart has (over 900 or so visits) a 93% success rate in finding these birds that have a knack for eluding less experienced birders. As it was we had to move out of the Lower Roosting Area, a half mile or so up from the trailhead, where he finds about 80% of his owls and ascend another quarter mile or so to the much more spread out Upper Roosting Area. The birds roost in some species of small-leaved oak providing them cover and cool during the day. Here's my best pic of the bird; there was no way to get a clear shot at the entire bird due to all the branches, thickety undergrowth, and mobility limited by the canyon walls.