The Little Bird at the Heart of a Big Ruckus : Environment: State panel tries to decide whether to declare the California gnatcatcher an endangered species. The creature suffers from an identity problem, though, including the fact that it doesn’t eat gnats.

It haunts scruffy thickets of brush dotting the coastal hills and valleys. Fluttering amid the sagebrush and buckwheat, incognito in slate-gray feathers, the California gnatcatcher seems the embodiment of the common bird.

But common it is not.

Much like the spotted owl in the Pacific Northwest or the endangered desert tortoise, the tiny songbird has become the centerpiece of an ongoing slugfest between big business and environmentalists, developers and slow-growth advocates.

Barbs continued to fly last week as the state Fish and Game Commission began weighing the gnatcatcher’s destiny--whether to declare it a candidate for endangered species status or, as biologists fear, allow the bird to skitter toward extinction. After half a day of testimony Thursday, the commission put off a decision until late this month.

As the human hubbub plays out, the gnatcatcher has remained something of a mystery, even to some of its most devout supporters and detractors. The bird has been written and argued about incessantly, converted into a symbol of both our embattled environment and our endangered economy. But few people know much about it.

With a wingspan no bigger than your palm, and a shrill, drawn-out call often compared to the plaintive mew of a kitten, the gnatcatcher is a bird that would be hard to dislike.

In fact, this tiny creature could teach us a thing or two. Ornithologists say the bird is industrious. When it comes to building a nest, both sexes are champion carpenters.

Gnatcatchers appear to stick to the same bushy neighborhood from year to year instead of periodically pulling up roots for greener pastures. They also typically prove devoted mates and doting parents. The gnatcatcher is also a virtuoso singer, trilling its tunes incessantly through the course of a day.

Despite such virtues, the bird has something of an identity problem.

For starters, the gnatcatcher does not eat gnats. Instead, it feasts on other types of small, sedentary insects plucked from certain bushes and brush. Aphids and small beetles are a gnatcatcher’s haute cuisine.

The tiny winged creature has also had something of a roller-coaster ride just getting recognized by biologists as a separate species, independent of other gnatcatchers scattered throughout the continent.

It was not always that way. In 1881, the California gnatcatcher was spotlighted as its own species, distinct from the more prevalent black-tailed gnatcatcher, which thrives in sections of the Southwest and in the heart of Mexico. In 1926, ornithologists reversed themselves and lumped the coastal bird with its inland cousin.

So it stayed for more than half a century. Finally, in 1988 the California gnatcatcher once again ascended to a spot as a distinct creature.

The final proof was in the bird’s voice.

Jonathan L. Atwood, then a doctoral candidate at UCLA, ventured to California gnatcatcher territory armed with a tape recorder. Atwood turned the volume up and, as gnatcatchers flitted about in the bushes, began playing recordings of birdcalls from a spate of species.

When the chirps of the black-tailed variety and others blared over the loudspeakers, the local gnatcatchers did not stir. Birds, after all, typically are not riled up by the calls of other species, which are not considered a threat to steal their mates, Atwood said.

When the distinctive mews of the California gnatcatcher echoed through the outback, the birds he was watching would invariably fly to the tape recorder and begin attacking it, suspecting that the machine was somehow one of their own trying to invade sovereign territory.

That evidence, along with plumage that is noticeably distinct from the feathers of the black-tailed variety, is cited by most ornithologists as proof that the California gnatcatcher--or Polioptila californica --is its own bird.

And a vanishing bird at that.

As development and agriculture have swept across Southern California this century, houses and farms gobbled up the gnatcatcher’s prime habitat, a rare mix of soft-wood bushes known as coastal sage scrub.

That arid scrub, which drops its leaves during dry spells, is now recognized as among the most quickly vanishing types of vegetation in the United States. Along with its demise has come the disappearance of the gnatcatcher and a host of other birds, reptiles and mammals that make their home in the coastal sage.

About half the remaining scrub is spread through San Diego County. Environmentalists say much of the prime gnatcatcher habitat in Orange County lies in two sweeping stretches owned by developers--the coastal hills held by the Irvine Co., and canyons northwest of Ortega Highway owned by the Santa Margarita Co.

Developers who oppose listing the bird as endangered say they have nothing against the gnatcatcher but believe that steps can be taken to set aside a sufficient amount of habitat without blocking their building plans.

Environmentalists strongly disagree. Most fear that the bird is teetering at the abyss.

Atwood--now a noted ornithologist at the Manomet Bird Observatory in Plymouth, Mass.--and other experts suspect that only 1,200 to 2,000 pairs are left, all of them residing in a narrow band near the Southern California coast from the Palos Verdes Peninsula to the Mexican border. At the present rate, the bird could be gone in 20 years, they contend.

The California Gnatcatcher

Once common throughout Southern California, the California gnatcatcher is now found only in patches Orange, San Diego, and Western Riverside counties and part of the Palos VerdesPeninsula. From 66% to 90% of its habitat, called coastal sage scrub, has already been destroyed, and many remaining areas are scheduled for redevelopment in the next few years.

The California gnatcatcher is found in sagebrush mesas and dry coastal slopes. It has a distinctive call, a rising and falling, kitten-like mew. Only about 4.5 inches in length, the gnatcatcher is blue-gray on top, with lighter-colored feathers underneath, and has a longish black tail.