Pacific Southwest Region
California, Nevada and Klamath Basin

U.S. Fish and Wildlife Service Protects the Mount Charleston Blue Butterfly Under the Endangered Species Act

Sep 18, 2013


September 18, 2013
Contact: Dan Balduini (702) 515-5480

U.S.Fish and Wildlife Service Protects the Mount Charleston Blue Butterfly Under the Endangered Species Act
Five similar butterfly species will not be listed

LAS VEGAS — The U.S. Fish and Wildlife Service (Service) today announced that the Mount Charleston blue butterfly will be given federal protections under the Endangered Species Act (ESA). The Mount Charleston blue butterfly is in danger of becoming extinct in the foreseeable future. The subspecies will be added to the List of Threatened and Endangered Wildlife and Plants, and the Service will work cooperatively with conservation partners to aid the butterfly’s recovery and address current and future threats.

The Mount Charleston blue butterfly (Plebejus shasta charlestonensis) is a distinct subspecies of the wider-ranging Shasta blue butterfly. The butterfly occupies high elevations in the Spring Mountains National Recreation Area, approximately 25 miles west of Las Vegas.

The Service first identified the Mount Charleston blue butterfly as a candidate for ESA protection in 2011, due to the threat posed by the loss and degradation of its habitat and inadequate regulatory mechanisms to prohibit collection of the butterfly. The species is likely to experience continued habitat loss due to changes in natural fire regimes and succession, fuels reduction projects, and the implementation of recreational development projects. Additionally, the growth of nonnative plants will increase the inherent risk of extinction for the Mount Charleston blue butterfly.

The Service also determined that federal protections under the ESA are not warranted for the lupine blue butterfly, Reakirt’s blue butterfly, Spring Mountains icarioides blue butterfly, and two Spring Mountains dark blue butterflies. In September 2012, when the Service proposed listing the Mount Charleston blue butterfly as endangered, the agency also proposed listing the five other butterflies as threatened, because they are similar in appearance to the Mount Charleston blue butterfly and share its habitat. However, the threat of inadvertent collection and misidentification of the Mount Charleston blue butterfly will be reduced by other regulatory measures put in place by the U.S. Forest Service to protect sensitive butterfly species in the Spring Mountains.

The ESA provides a critical safety net for America’s native fish, wildlife and plants. This landmark conservation law has prevented the extinction of hundreds of imperiled species across the nation and promoted the recovery of many others. Our priority is to make implementation of the ESA less complex, less contentious and more effective. We seek to accelerate recovery of threatened and endangered species across the nation, while making it easier for people to coexist with these species.

The Federal Register Notice detailing the butterfly’s endangered status can be found here.

The Service will propose designating critical habitat in the Spring Mountains that contains host and nectar plants and open areas essential to the conservation of the species. The proposal will be published in a separate Federal Register Notice in the near future.

The mission of the U.S. Fish and Wildlife Service is working with others to conserve, protect, and enhance fish, wildlife, plants, and their habitats for the continuing benefit of the American people. We are both a leader and trusted partner in fish and wildlife conservation, known for our scientific excellence, stewardship of lands and natural resources, dedicated professionals, and commitment to public service. For more information on our work and the people who make it happen, visit Connect with our Facebook page at usfwspacificsouthwest, follow our tweets at watch our YouTube Channel at and download photos from our Flickr page at