Endangered and Threatened Wildlife and Plants; Emergency Rule To List the Carson Wandering Skipper as Endangered

We, the U.S. Fish and Wildlife Service (Service), exercise our emergency authority to list the Carson wandering skipper (Pseudocopaeodes eunus obscurus) in California and Nevada as endangered under the Endangered Species Act of 1973, as amended (Act). The Carson wandering skipper is currently known from only two populations, one in Washoe County, Nevada, and one in Lassen County, California. The subspecies is found in grassland habitats on alkaline substrates. Extinction could occur from naturally occurring events or other threats due to the small, isolated nature of the remaining populations of the Carson wandering skipper. These threats include habitat destruction, degradation, and fragmentation due to agricultural practices (such as excessive livestock grazing and wetland habitat modification), urban development, and non-native plant invasion. Other threats include collecting, livestock trampling, water exportation projects, road construction, recreation, pesticide drift, and inadequate regulatory mechanisms. We find these threats constitute immediate and significant risk to the Carson wandering skipper. This emergency rule provides Federal protection pursuant to the Act for the Carson wandering skipper for a period of 240 days. A proposed rule to list the Carson wandering skipper as endangered is published concurrently with this emergency rule in this issue of the Federal Register in the proposed rule section.