Along the reservoir's banks certain protected coves have managed to maintain a degree of shadowy greenness. Last Sunday morning as I passed by one such cove, below me suddenly there erupted a loud, rich CHOO! and a silhouette escaped furtively through shadowy underbrush. The bird didn't want me to see him but eventually I got him in focus. All I could see was his form -- longish tail with longish, slender beak -- but no colors at all, just blackness. Well, I'd heard that CHOO! before, from dozens of other shadowy underbrushes, so I didn't really need to see color to know who it was. It was the Blue Mockingbird, endemic to Mexico north of the Isthmus, a pretty picture of which you can see at http://www.southfloridabirding.com/bluemockingbird.jpg.
That picture shows a truly blue bird with the familiar long-tailed mockingbird shape. However, most of the times I've seen this bird I haven't glimpsed any blue at all. A black silhouette among black shadows is about right for this bird, along with its disjointed series of sharp, singly articulated and highly varied whistles, which sometimes are decidedly ventriloquial. You look at the bird, see his bill open and his throat pumping, but the notes are coming from a few feet to his side.
And this bird has another trick, too. After you try and try to get a good view as he manages to remain just a black shadow down among many black shadows, once you give up, he's very likely to abruptly fly onto a completely exposed perch and sing as unrestrainedly as any gringo mockingbird in a magnolia. One suspects a certain sense of humor in this bird.
Eastern North American birders know that mockingbirds, Brown Thrashers and catbirds are all members of the same family. Mockingbird songs usually consist of notes repeated three or more times. Brown Thrashers repeat their notes twice, and catbirds just string together a series of once-stated notes. Thinking in these terms, the Blue Mockingbird with his train of once-stated notes is close to the catbird. In fact, if you add a little blue to the dark catbird, you almost have our Blue Mockingbird.
But, our Blue Mockingbird has a bit more pizzazz than a catbird, more color, a stronger voice and certainly more quirkiness.
He's a perfect bird to call out CHOO! on a perfectly summery day in January, from a shadowy Mexican thicket on a perfect Sunday morning.