Wildlife. The Fight for Space. : As homes march up hillsides and offices sprout on fields, Orange County’s wildlife battles for its dwindlng habitat. : FULLERTON : Fighting to Preserve Gnatcatcher Habitat

Cool breezes sweep between working oil wells in the eastern Coyote Hills. Birds and lizards flit through the scrub brush and grass that cover the hills.

Within five years, many of the oil wells and much of the scrub brush may be replaced by houses and a golf course.

Environmentalists say the development threatens part of the habitat of the California black-tailed gnatcatcher, a lively little gray bird with a black tail that makes a home in the hills south of Bastanchury Road and west of State College Boulevard.

“It’s a cute little animal,” said Joel Weintraub, a professor of biology and environmental studies at Cal State Fullerton. “It’s a real flitty sort of animal. It certainly appeals to people and is one of the first to leave when the coastal sage scrub disappears.”

While the gnatcatcher, which was declared last year to be a separate California species, is not on the federal government’s endangered species list, both environmentalists and the developer are taking steps to help maintain its habitat.

Unocal Land & Development Co.’s plans to build 800 residential units and an 18-hole golf course on about 350 acres of eastern Coyote Hills include saving areas of virgin coastal sage in which the bird thrives, according to a company spokesman.

The coastal sage scrub was once plentiful in Southern California, but much of it has been replaced by housing tracts and shopping centers.

Although the bird is widely distributed in Baja California, it exists in the United States only in the coastal strip from the Palos Verdes Peninsula to the Mexican border.

In 1980, ornithologist John Atwood estimated the black-tailed gnatcatcher population at 1,335 pairs in Southern California, 325 of them in Orange County. Barry Eaton, chief planner for Fullerton, said five or six pairs of the bird have been sighted in eastern Coyote Hills.

“The problem with that species is that they are very, very restricted to that sage scrub environment, which is being developed,” Atwood said.

Coastal sage scrub is a plant community made up of California sagebrush, white sage, black sage and elderberry, toyon or other plants.

Last year, the American Ornithologists Union recognized the unique character of the gnatcatcher in the United States by elevating it from a subspecies of the coastal gnatcatcher to its own species, the California gnatcatcher.

Although the California gnatcatcher looks much like other gnatcatchers, its song sets it apart, Atwood said. Gnatcatchers in desert areas have a wren-like chatter--a repetitious single-note song--while the California gnatcatcher sounds something like a mewing kitten.

The gnatcatcher has been designated as a species of special concern by the state. The federal Fish and Wildlife Service is reviewing the status of the bird, which should be completed in three or four months.

Should the gnatcatcher make the endangered species list, it would dramatically affect development in the area.

If the bird becomes listed, “it’ll stop the plan until a habitat conservation plan is developed,” said Eric Ruby, director of environmental services for Planning and Design Solutions, a consulting firm hired by Unocal.

The consultant will study the gnatcatchers during the spring breeding season and is helping to design development plans to protect the gnatcatcher’s habitat, Ruby said.

“You can’t ignore them. The bird will be addressed in the (environmental impact report), and we will take necessary steps to save one-half to three-fourths of the habitat,” said Barry Lane, manager of public relations for Unocal.

A draft of the environmental report should be complete and ready to submit to the city in about six months, Lane said.

Caryla Larsen, a biologist with the state Fish and Game Department, said that even if the bird is eventually listed as endangered, it might be too late for the species, because development is happening so rapidly and the process to list a species is long and complicated.