Center for Biological Diversity

For Immediate Release, February 22, 2018

Contact: Chris Nagano, (916) 765-9097,

Lawsuit Launched to Speed Endangered Species Protection for Giant California Fly

Hummingbird-like Flower-loving Fly Faces Extinction Following Federal Delay

LOS ANGELES— The Center for Biological Diversity today filed a notice of intent to sue the U.S. Fish and Wildlife Service for failing to protect the San Joaquin Valley giant flower-loving fly under the Endangered Species Act.

The giant fly has been lost from more than 99 percent of its former range and survives in only one population about 15 miles east of Bakersfield, where it is under immediate threat of extinction from sand mining at Sand Ridge.

Although once found in scattered sandy habitats throughout the San Joaquin Valley north to the Antioch Dunes of Contra Costa County, the fly is now so rare that it was thought to be extinct until two populations were rediscovered near Bakersfield in 1997. One of those two, at a site 10 miles south of Bakersfield, was exterminated by sprawl development in 2006.

“The Fish and Wildlife Service needs to stop sitting on its hands while this unique species is pushed toward the brink of extinction,” said Chris Nagano, a senior scientist and entomologist at the Center. “We should protect all imperiled creatures great or small, because every species plays an important role in the web of life.”

The San Joaquin Valley giant flower-loving fly resembles a stealth fighter. It can hover in mid-air and then instantly fly away at speeds difficult for the human eye to follow. Detailed studies of the high-speed, aerobatic flight and the structure of the eyes of a related fly led to advances in the U.S. Air Force’s missile tracking systems.

Two California entomologists petitioned for emergency protection of the San Joaquin Valley giant flower-loving fly in June 2014. The Service determined in April 2015 that protection may be warranted, but has failed to either propose or deny listing. The decision is now more than three years overdue. The giant flower-loving fly was first identified as being in need of federal protection by the Service in 1991.

The fly is close in size to a small hummingbird, with a 1.5-inch body and long proboscis, or tongue. The species plays a critical role in its sand-dune ecosystem, serving as food for birds and other predators and feeding on other invertebrates in its early stages. Surprisingly, the extremely active adults have never been observed to feed. 

“Insects are understudied worldwide, but many are highly threatened and our wildlife agencies should start prioritizing protection for this important group of animals,” said Nagano.

San Joaquin Valley giant flower-loving fly

Photo by Greg Ballmer. This image is available for media use.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1.6 million members and online activists dedicated to the protection of endangered species and wild places.

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