State Scientists Set Guidelines to Protect Bird : Environment: Stringent standards for protecting the threatened gnatcatcher call for sparing 95% of Southern California’s remaining sage scrub from development for several years.

Ninety-five percent of the remaining sage scrub in Southern California must be spared from development for several years to guarantee the survival of the California gnatcatcher and other imperiled creatures, according to guidelines issued Wednesday by a state panel of scientists.

The stringent new guidelines set the framework for a novel state experiment in creating wildlife preserves for the gnatcatcher--a tiny songbird that the Interior Department declared a threatened species last week--and about 75 other birds, lizards, mammals and plants that share the gnatcatcher’s habitat.

Local governments and developers are supposed to use the scientists’ advice to launch the long, difficult process of planning permanent preserves for the rare wildlife. The idea of the program, created by Gov. Pete Wilson’s Resources Agency, is to reach voluntary agreements to protect large mosaics of natural lands, focusing on the sage scrub homes of the gnatcatcher.

Dennis Murphy, a Stanford University wildlife biologist who chairs the state’s five-member scientific panel, said the scientists concluded that the condition of Southern California’s natural lands “is as bad as it looks.”

“It is very clear that coastal sage scrub is in trouble and needs protection,” he said. “If we’re only going to lose 5% more, I’d be one happy conservation biologist. But, in fact, I believe there will be pressures above and beyond that 5%.”

Following the advice of the scientists is not mandatory. But city and county officials will face pressure to follow it because state and federal wildlife agencies have veto power. Interior Secretary Bruce Babbitt has warned that the federal government will exert control over Southern California development under the Endangered Species Act if the state program fails to protect the gnatcatcher.

Murphy said that, ideally, not even one more acre of the habitat should be bulldozed because it is already so depleted that species such as the gnatcatcher are edging toward extinction. But realistically, he said, development pressures are so intense in Southern California that a 5% loss is tolerable.

The clash is intense because the sage scrub grows in the same low-lying hills and mesas--some with commanding ocean or canyon views--that are coveted by builders of large housing subdivisions and other projects.

Developers and environmentalists who have been eagerly awaiting the scientists’ guidelines were guarded in their reaction Wednesday.

Several developers said they were not alarmed at the prospect of a temporary ban on developing virtually any of the remaining habitat. Because of the sluggish economy, construction is almost at a halt in Southern California.

“Nobody screamed mortal pain--not the developers, not the environmentalists. They screamed pain, but not mortal pain,” Murphy said. “The fact that they’re not screaming up front means that I think we have a percentage everyone can live with.”

The scientists called their plan conservative--erring in favor of wildlife.

They recommend that the 95% restriction remain in place until more data is collected and preserves are created--which they said could take three to six years. The idea, Murphy said, is to limit the damage until more research determines which lands are critical to preserve permanently.

Environmentalists generally were pleased by the scientists’ rules. Dan Silver of the Endangered Habitats League, a coalition of about 50 California environmental groups, called them “very strict and conservative.”

They worried, though, that the scientists’ advice might not be enforced by city and county officials who have the most immediate power to approve development.

“Who’s going to say no to the big developers like the Irvine Co.?” said Ann Notthoff of the Natural Resources Defense Council. “There’s great flexibility in these guidelines. Is there enough teeth in them to mean there really won’t be development on the highest value lands (for wildlife)?”

State officials running the program acknowledged that politics will mingle with science to eventually determine how much and which land is saved.

“Biologists say, ‘Save it all and fix the rest.’ But we’re making trade-offs,” said Tom Reid, a consultant to the California Department of Fish and Game, which is overseeing the state conservation program. “I’m not saying it’s all politically negotiable. What I’m saying is we have now developed scientific tools for making these political decisions that provide guidance to local governments.”