I rose very early on this day ten years ago, early enough to hear the predawn flight-singing
of the Violet-Green Swallows, and well before the local Mexican Whip-poor-will wrapped up his
nocturnal broadcast. I had a mile to cover before the Cordilleran Flycatchers wrapped up their
brief predawn performance, which I had come a thousand miles to record. (I will tell their story on June 16.)
But, I got there in time. They sang,
I recorded, and their songs have since been measured and added to a database. And then, with my
mission accomplished, it was time to have some fun.
Some of my fun consisted of recording a Canyon Wren sitting on a rock at point-blank
range. Some consisted of marvelling at the songs of the Black-crested Titmice. I had some fun comparing the
vegetation of this outpost of the Sierra Madre Oriental with the vegetation of the Arizonan outposts of the Sierra Madre Occidental.
But of course the biggest
local attraction is the Colima Warbler. This is the only place in the U.S. they nest, and so the only
place to find them with confidence. My friend John Egbert spent a summer with them in the 1970s,
collecting some of the data for Ro Wauer's reports. I'm not sure anyone has spent as much time with them since then.
All I had was an hour, or two if I pushed it. But, they do live in Boot Canyon, and soon one sang.
I saw him. He looked like an oversized Virginia's Warbler who had just taken a dust bath. He is in fact the
replacement for that grayer species in the Madrean pine-oak woodlands from here south.
The Virginia's occupies dry woodlands of the southwestern U.S., all the way to the Mexican border in Arizona,
and south to the Davis Mountains one hundred miles north of here. To the north
it is replaced in shrubby conifer forests by the Nashville Warbler. If the Colima followed the usual pattern, as the Mexican Jay
and Blue-throated Mountain-gem, and dozens others, do, it would occupy both branches of the Sierra Madre. But, it's
not over there to the west, on the border of Sonora and Chihuahua. It's only over here. I wonder why.