Gulf Fritillaries Doing Well

Apr 1, 2024

The Gulf Fritillary, Agraulis vanillae, is definitely back from a comeback, at least in the Sacramento, Davis and Vacaville-Fairfield areas.

In September of 2009, butterfly guru Art Shapiro, now a UC Davis distinguished professor emeritus,  excitedly announced the re-appearance of the Gulf Fritillary butterfly in the Sacramento metropolitan area after a four-decade absence, and in the Davis area after a 30-year absence.

The showy butterfly colonized both south Sacramento and the Winding Way/Auburn Boulevard area in the 1960s but by 1971 "apparently became extinct or nearly so," recalled Shapiro, who has monitored the butterfly populations of central California since 1972 and maintains a research website at

It's a tropical and subtropical butterfly with a range that extends from the southern United States all the way to central Argentina. 

No one knows exactly when the first Gulf Frit first arrived in California, but "it was already in the San Diego area by about 1875, Shapiro says, and it was first recorded in the San Francisco Bay Area around 1908.

A recent piece in The Acorn, published by the Effie Yeaw Nature Center, Carmichael, and authored by UC Davis entomologist Mary Louise Flint (see article), indicated the Gulf Fritillary is doing well in the area. 

Good news!