Early California butterfly enthusiast John A. Comstock was enchanted by the Hermes copper butterfly, describing it in 1927 as “a fascinating little sprite.” But even as far back as the '20s, it was clear that the insect was endangered by the creeping threat of urbanization. Said Comstock: “It will always be a rarity, and may, in fact, some day become extinct, if San Diego continues to expand at its present rate.” More recently, devastating wildfires have burned through key Hermes copper habitat, putting an end to the tenuous existence of many remaining populations. Soon, as Comstock predicted, the butterfly may no longer “dart about in the sunshine” at all.

In 1984, the butterfly was dubbed a Category 2 candidate under the Endangered Species Act — a designation once given to species for which listing “might be warranted,” but for which there was supposedly insufficient data to justify a listing proposal. In 1996, the Category 2 list was abolished, and even the butterfly's third-rate listing status was removed. In 2003, 19 of the remaining Hermes copper populations were destroyed by fires that ripped through the butterfly's habitat.


The Center for Biological Diversity and San Diego Biodiversity Project filed formal petitions in 1991 and 2004 to protect the Hermes copper butterfly. It took a 2005 lawsuit to make the Service respond to our second petition, but the agency announced in 2006 that it wouldn't protect the species, despite the 2003 fires burning nearly 40% of the butterfly’s habitat.

The Center filed a second lawsuit in 2009, but the Service delayed protection by placing the butterfly back on the candidate list in 2011. So the Center sued a third time in 2019, which finally forced the Service to propose a status of threatened in early 2020.

Finally, in 2021, the Service protected the Hermes copper butterfly as threatened under the Endangered Species Act.

We're also opposing uncontrolled urban sprawl that threatens the Hermes copper and working against the construction of Sunrise Powerlink, a high-voltage transmission line proposed for San Diego County, through the habitat of the Hermes copper and other imperiled species.

Check out our press releases to learn more about the Center's actions for Hermes copper butterflies.

Photo © Douglas Aguillard