In late spring our desert Northern Mockingbirds start to defend their nests again, harassing just about every living thing that comes near. Their absolutely fearless defense probably puts it in the running for bravest animal in the desert. It certainly makes it a contender for most annoying, at least to some people. Mockingbirds are one of those wild animals that do much better in cities than they do in the wild; they have a tendency to build nests near houses. Residents of such houses may find themselves being strafed by a tiny, two-ounce bit of feathers and beak in April & May. The single thing mockers seem to hate most is cats. The parents can even solicit help from outsiders as unrelated Mocker often defends other’s nests. A persistent alarm call from a besieged mocker can recruit several other adults to the area to harass the stubborn cat, or whatever.
The babies fledge in summer and the adults blood pressure declines slightly, though mockers never really become unaggressive. Mated couples may part, or they may start the process over again. A pair can raise two or three broods in a breeding season, and go on monogamously to do the same thing next year.
Both sexes sing, though it’s usually unmated males who are the loudest, and who keep on going after last call. Skilled mimics, a mocker can sing another bird’s song well enough to fool an accomplished birder, though actual birds seldom seem to be taken in. A male mocker can learn as many as 200 distinct songs in its decade-long typical life span, including not just other birds’ songs but even car alarms:
In the Bay Area, a neighbor inadvertently trained a generation of local mockers to imitate his overactive car alarm and for the next few years you could hear the mockingbirds’ imitation persist, slowly gaining improvised passages and becoming modified here and there with other bird’s songs being folded into the auto security mix. A mockingbird’s song is an echo of the chorus of sounds that surround it. Whether by singing us awake at 3:40 or dive bombing us on our way out of the house too few hours afterward, they remind us that there’s a natural world just outside our door.
