Center for Biological Diversity

For Immediate Release, August 8, 2022


Patrick Donnelly, (702) 483-0449,

Endangered Species Protections Sought for Rare Nevada Butterfly

Bleached Sandhill Skipper Among Growing Number of Species Threatened by Poorly Sited Geothermal Energy

RENO, Nev.— The Center for Biological Diversity petitioned the U.S. Fish and Wildlife Service today to grant Endangered Species Act protection to an extremely rare butterfly called the bleached sandhill skipper.

The butterfly is restricted to a single alkali wetland in Humboldt County, Nevada. It could face extinction if the Baltazor Geothermal Development Project, proposed by developer Ormat, proceeds.

Geothermal energy, while a carbon-free power source, has a well-documented history of drying up nearby springs. Across the globe hot springs adjacent to geothermal projects have gone dry or cooled off, with significant impacts on native biodiversity. If the hot spring which creates this butterfly’s habitat dries up, it will go extinct.

“The bleached sandhill skipper is a unique piece of Nevada’s phenomenal biodiversity, and we’re doing everything we can to prevent its extinction,” said Patrick Donnelly, Great Basin director at the Center for Biological Diversity. “Geothermal energy is an important part of our clean energy transition, but it can’t come at the cost of extinction.”

Bleached sandhill skippers are under 2 inches long and get their name from their yellow and beige markings, lighter in color than those of their closest cousins. The butterflies live in a single alkali wetland of around 1,500 acres created by discharge from the boiling hot Baltazor Hot Spring.

Their home meadow is full of saltgrass, presumed to be the butterfly’s larval host plant. In autumn the skippers emerge as adults and fly for a period of just a few weeks, nectaring in dense groups on the abundant rabbitbrush surrounding the wetland.

Ormat’s geothermal project is sited just across SR-140 from Baltazor Hot Spring. If Ormat pumps and recirculates billions of gallons of water per year, as proposed, it is likely to significantly alter the discharge at Baltazor, potentially drying up the wetland, killing off the saltgrass and rabbitbrush, and driving the bleached sandhill skipper to extinction.

“This beautiful little butterfly has evolved over millennia to thrive in this one specific spot, and no one should have the right to just wipe it off the face of the Earth,” said Jess Tyler, a staff scientist at the Center and petition co-author. “I urge the U.S. Fish and Wildlife Service to act fast to protect this amazing creature and its hot spring habitat.”

In April the Service gave emergency Endangered Species Act protection to the Dixie Valley toad due to the acute extinction threat it faced from the construction of the Dixie Meadows Geothermal Project, which was also proposed by Ormat. Dixie Meadows is a hot spring-fed wetland in Churchill County, Nevada.

RSBleached_sandhill_skipper_Patrick_Donnelly_Center_FPWC (1)
Bleached sandhill skipper/Patrick Donnelly, Center for Biological Diversity Image is available for media use.
Baltazor Hot Spring/Patrick Donnelly, Center for Biological Diversity Image is available for media use.

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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