THE WHOLE TREE was tittering. "Peeps" and "tits" rained from the canopy like little sonic cherries, the thin, fragile sounds beginning with a consonant and trailing off into thin, high-pitched air.
Suddenly, a tiny--the size of a hummingbird--plain brown bird erupted from the canopy and churned its way through the air toward the next tree up the street. A second one followed, then two more, then three, one, two, one, until a ragged procession of 25 or so had reassembled in a new tree. Then that tree began to titter.
Which is how the bushtit travels through the neighborhoods of Southern California. Relatives of the chickadee, bands of these drab, long-tailed birdlets hop and flutter through the thickest foliage to raid the smallest of insects and mites. Tittering constantly, they use sound to keep in touch with one another, each member broadcasting its position, each member in turn aware of the position of its peers. A band of bushtits is so closely knit, the individual members so attuned to the presence of the others, that the group amounts to a sort of giant organism. It diffuses like fog through backyard shrubbery, penetrates the darkest nooks and crannies, relieves the foliage of its excess and unwary bugs, and flows off over the back fence and on across the city, just one more little creature trying to make ends meet in the teeming suburbs of Southern California.