Center for Biological Diversity

For Immediate Release, June 29, 2020


Tara Cornelisse, Center for Biological Diversity, (971) 717-6425,
Dan Silver, Endangered Habitats League, (213) 804-2750,

Petition Seeks California Endangered Species Protection for Quino Checkerspot Butterfly

SAN DIEGO The Center for Biological Diversity and Endangered Habitats League filed a petition today to protect Quino checkerspot butterflies under the California Endangered Species Act.

The petition, filed with the California Fish and Game Commission, notes that the Quino checkerspot butterfly was once one of the most common butterflies in Southern California. But with the rapid spread of sprawl development, the butterfly lost more than 75% of its habitat and in 1997 was listed as endangered under the federal Endangered Species Act. In 2002, despite continued habitat loss, the U.S. Fish and Wildlife Service reduced the butterfly’s designated critical habitat by 63.8%.

“It’s alarming that a butterfly that once filled the skies of Southern California is now only found in pockets of its former range,” said Dr. Tara Cornelisse, an entomologist and senior scientist at the Center. “Even more alarming is that some of those few critical patches of remaining habitat are slated to be developed. With insects declining at a frightening rate, we need to protect more habitat for endangered butterflies, not allow it to be carved up piece by piece.”

Despite federal protection the Quino checkerspot butterfly remains at great risk of extinction due to continued habitat destruction and fragmentation, climate change, nitrogen pollution, invasive species and lack of enforced protections. In the past 10 years, the once ubiquitous butterfly has only been observed in 33 of 62 potential sites and only inhabits patches of southern San Diego and southwest Riverside counties.

At least six major development projects slated to begin imminently or within the next few years will impact the Quino checkerspot butterfly’s few remaining populations. These developments total more than 6,500 acres. Two of those projects would impact hundreds of acres of the most important Quino core habitat near Chula Vista in San Diego County, with mitigation that relies on unproven restoration of degraded habitat.

In addition, the Trump administration’s border wall is destroying more of the butterfly’s critical habitat as well as its connectivity to populations in Mexico.

“By first decreasing the butterfly’s designated critical habitat and then allowing large-scale development projects within its few remaining strongholds, the Trump administration has failed to protect this endangered butterfly,” said Dan Silver, petition coauthor and executive director of Endangered Habitats League. “To have a chance at surviving rampant development and other threats like climate change and invasive species, the Quino checkerspot butterfly urgently needs California state protection.”

Under the California Endangered Species Act, the California Department of Fish and Wildlife has three months to make an initial recommendation to the Fish and Game Commission, which will then vote on the petition at a public hearing. If the Quino checkerspot butterfly wins protection under the Act, the state can enact its own protections, giving the butterfly a chance at survival.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1.7 million members and online activists dedicated to the protection of endangered species and wild places.

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