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For Immediate Release, March 17, 2009

Contact: Jonathan Evans, Center for Biological Diversity, (415) 436-9682 x 318

Conservation Group Seeks Protection for Endangered Butterflies

SAN DIEGO, Calif.— The Center for Biological Diversity filed suit today seeking protection of two of Southern California’s rarest butterflies, the Hermes copper and Thorne’s hairstreak. The suit challenges a 2007 decision by the U.S. Fish and Wildlife Service denying protection for the butterflies under the Endangered Species Act.

“Sprawl, rampant wildfires, and climate change threaten to wipe these two beautiful creatures off the planet,” said Jonathan Evans of the Center for Biological Diversity. “We must act now to protect these butterflies and their islands of habitat in the mountains so they are not lost to future generations.”

Described as “two of nature’s unique gems,” the butterflies are in continued peril. They live in the coastal and mountain areas of San Diego County and are threatened with extinction by the competing threats of suburban sprawl, increased wildfires, and climate change.

Conservation groups have sought protection for the threatened butterflies for almost 20 years. In 1991 and 2006, David Hogan and the Center for Biological Diversity filed formal petitions with the federal government to protect the butterflies. Today’s suit seeks to overturn Fish and Wildlife’s rejection of the more recent petition.

Documents obtained under the Freedom of Information Act reveal that the Bush administration reversed the course of its own biologists who recommended further research into protection of the butterflies under the Endangered Species Act. Biologists and agency staff concluded that enough information existed to warrant protection and to continue a “status review” in order to further investigate protection. Those decisions were ultimately reversed.

“It will take years to clean up the Bush administration’s abysmal record on wildlife conservation,” said Evans. “Extending endangered species protections to these butterflies will help return science to government decisions.”

The Hermes copper butterfly

The Hermes copper is a bright, yellow-orange spotted butterfly that is dependent for survival on small areas of its host plant, the spiny redberry. The Hermes copper occupied many coastal areas prior to urbanization, and still occupies some foothill and mountain areas up to 45 miles from the ocean.

As early as 1980, staff at the San Diego Natural History Museum noted “with San Diego’s increasing growth and the distributional nature of this little endemic butterfly, its future may well rest in the hands of developers.” Files of the U.S. Fish and Wildlife Service recognized the substantial threat from wildfire: “Carlsbad FWS office files contain substantial information regarding threat of wildfire due to increased human-induced fire” due, in part, to the 2003 fire that “burned 39% of Hermes copper habitat” including “large stands of the species’ larval host plant and entire colonies.”

The Thorne’s hairstreak butterfly

The Thorne’s hairstreak is a delicate butterfly with wings that range from reddish brown to mahogany brown with lavender overscaling. The Thorne’s hairstreak butterfly has an extremely limited geographic range, existing in only one small area on Otay Mountain in San Diego County. This limited range is due, in part, to the limited distribution of its host plant, the Tecate cypress, upon which it depends.

The Thorne’s hairstreak has been recognized as unique and imperiled for more than 20 years. Unfortunately, the status of the Thorne’s hairstreak butterfly continues to deteriorate due to the increased threat of wildfire posed by an increasing human population and illegal migration across the Mexico border. Because of this limited distribution, one wildfire event could wipe the species off the planet. In fact, the 2003 wildfire event reduced the Thorne’s hairstreak occupied locations by half, from ten to five. Prior to the 2003 wildfires, biologists estimated that about 400 Thorne’s hairstreak butterflies remained in about eight populations. After the fire, surveys turned up fewer than 100 individual butterflies in four to five locations.


The Center for Biological Diversity is a national, nonprofit conservation organization with more than 200,000 members and online activists dedicated to the protection of endangered species and wild places.

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