The California Academy of Sciences used genetic testing to identify a blue butterfly species similar to the Xerces species that went extinct and disappeared from the San Francisco coastline. Through careful planning and collaboration with the Presidio Trust and the Xerces Society, scientists restored lost habitat and reintroduced blue butterflies to the area.
The Brief
- Cal Academy of Sciences and The Presidio join conservation efforts to bring blue butterflies back to San Francisco coast.
- Genetic sequencing links Silvery blue butterflies to extinct Xerces blue.
- From March through May 2025 scientists hope to see new generation of silvery blue butterflies emerge after introduction to new Presidio habitat.
OAKLAND, Calif. – In the San Francisco Bay Area, the Xerces blue butterfly went extinct along the San Francisco coast some 80 years ago, but now the California Academy of Sciences and the Presidio Trust have identified a similar species of blue butterfly and are trying to introduce it back to the region where the Xerces blue butterfly was once so common.
Durrell Kapan, a senior research fellow at the California Academy of Sciences, is part of that effort and spoke with Jana Katsuyama on the Four to explain the effort:
Why did the Xerces blue butterfly go extinct?
Most butterflies…most organisms that go extinct are due to habitat loss. So California, after the gold rush, especially San Francisco, saw a lot of development. And so most people don’t know that most of San Francisco was awash with dunes. Pretty much the first two-thirds away from the ocean was all dunes. That was a perfect habitat for a butterfly, a little blue butterfly, that flew, feeding on a specific host plant called deer weed. It’s a pea family plant with an orange and red flower. Those plants didn’t have the dunes to live in, and the butterflies didn’t have the plants or the dunes, and so they went extinct.
A similar species
Now you have identified butterflies that are very closely related: the Silvery Blue butterflies that are in Monterey County. How did you use genetic sequencing to identify the connection between these two species?…