It isn't exactly the poster child for the Endangered Species Act.

But a little, brightly colored butterfly that lives only in San Diego County is in need of federal protection, biologists and conservationists say.

The environmental group Center for Biological Diversity filed suit in San Diego federal court last month to force the U.S. Fish and Wildlife Service to provide that protection for the Hermes copper butterfly by declaring it a threatened or endangered species.

And it just so happens that the Hermes butterfly prefers the same thick, decades-old chaparral that burned in the San Diego County wildfires of 2003 and 2007, and which county officials want to thin out to prevent more infernos.

The group filed the lawsuit after the federal agency rejected its petition to place the insect on the endangered species list in August 2006. The center is hoping for greater success under the Obama administration than it had under former President George W. Bush.

The butterfly used to be seen widely through much of San Diego County. Today, it is concentrated in the chaparral plant communities along Interstate 8. In North County, the butterfly has been seen recently only in the vicinities of Rancho Penasquitos and Rancho Santa Fe, biologists say.

"It isn't a baby polar bear or a bald eagle," said David Hogan, the former center employee who filed the petition and works as an independent environmental consultant in Pine Valley. "But it is just as important because it is beautiful in its own right."

The Hermes copper butterfly is about the size of a quarter, Hogan said.

"When its wings are open, it has a bold yellow pattern with brown spots in the center of its wings and brown trim around the perimeter," he said.

Hogan said the butterfly serves an important purpose: It pollinates plants in the sage scrub and chaparral landscapes that dominate San Diego County.

Ken Osborne, a Riverside-based insect biologist who studies San Diego County butterflies, said the butterfly has few cousins.

"There is nothing else like it in the world," Osborne said. "It is one of these old relics that doesn't have any relatives nearby."

The Hermes butterfly is one of the region's rarest insects, Hogan said, adding there are fewer than 20 populations -- or colonies -- left among more than 50 that biologists have documented over the last 100 years.

Yet, it never has enjoyed federal protection despite a pair of petitions to place it on the endangered species list.

The fight over chaparral

Hogan filed both petitions; the first in 1991 and the second in 2004. Both were rejected as having failed to prove the insect was in jeopardy.

Hogan filed the second petition following the Cedar, Paradise and other fires of October 2003. That wave of wildfires wiped out almost 40 percent of the butterfly's habitat, according to biologists.

Because so much habitat was destroyed, the latest petition warned that the county's proposal to reduce the wildfire threat by thinning decades-old stands of chaparral, through so-called prescribed burns, would jeopardize the insect's survival.

San Diego County Supervisor Bill Horn disputed the notion that the butterfly is threatened by the county plan adopted earlier this year.

"If it still exists, then obviously we didn't do away with it," Horn said.

The plan aims to create fire breaks, or open areas in the backcountry, through burns and trimming to keep out-of-control wildfires from racing unchecked into the city again, Horn said. Such breaks could aid the butterfly, he said, by preventing wildfires from wiping out chaparral all at once.

Horn also stressed that the county is planning to remove relatively small amounts of brush.

"It is not the 'burn everything' " plan, he said.

Still, Osborne said prescribed burns are in direct conflict with efforts to save the butterfly because they target the very habitat it requires.

And with the massive loss of mature chaparral stands in 2003, Hogan said, the butterfly cannot absorb more losses.

"We felt the status of the butterfly was so precarious after the 2003 fires that we asked for emergency protection," Hogan said. "At that time there were fewer than 20 populations of the species left, and many of those were just a tiny number of butterflies."

Jane Hendron, a spokeswoman for the Fish and Wildlife Service in Carlsbad, declined to talk about the butterfly's status.

"Unfortunately, because they have taken the process of initiating legal action against us, we can't discuss it," Hendron said.

She said the service's 2006 ruling "speaks for itself."

The ruling states: "We have determined that information in the petition does not substantiate the claim that urban development, wildfire and prescribed fire has significantly reduced the amount of available Hermes copper butterfly habitat. … Thus, we do not believe the petition has presented substantial information to suggest the butterfly is likely to become endangered in the foreseeable future."

A spark from extinction

Hogan maintains the Hermes copper butterfly is on a precarious perch. All it could take is a tossed cigarette butt, a vehicle backfire or a migrant camp fire during high wind along a backcountry highway, he said, and the butterfly could be knocked off that perch.

"Any single Santa Ana event with an accidental fire could be the extinction of the species," he said.

It is not difficult to envision how that might happen, said Michael Klein, a biological consultant in San Diego who has studied the insect extensively.

Klein said the 2003 Cedar fire, in one fell swoop, wiped out one of the largest populations of Hermes butterflies on the state-owned Crestridge Ecological Reserve east of El Cajon.

"We lost every colony, over 1,000 butterflies," he said. "In 2005, I observed one butterfly at Crestridge -- one."

Klein, who supports federal protection for the butterfly, said he is working with another biologist on a study of the wildfire threat. They are hoping to publish their findings in a scientific journal next year.

The butterfly relies entirely on one plant for food, the spiny redberry, which is found in both coastal sage scrub and chaparral habitats.

While it used to live along the coast, the butterfly was pushed out by urban development long ago.

As recently as the 1960s, it could be found in the Olivenhain area. But it hasn't been seen around there since. Klein said the closest it gets to the ocean these days is the Del Dios-Rancho Santa Fe area.

The butterfly also was spotted recently on Black Mountain in Rancho Penasquitos.

In the past, it was found in such places as Poway, Pala, Bonsall and Bernardo Mountain in Escondido -- but never north of San Diego County.

Today, the best place to view the Hermes is at Mission Trails Regional Park, Klein said. He said the insect's flight season runs from mid-May through June.

Contact staff writer Dave Downey at (760) 745-6611, Ext. 2623, or ddowney@nctimes.com.

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