LACEY, Wash. – The U.S. Fish and Wildlife Service (USFWS) has made the final determination to list the island marble butterfly (Euchloe ausonides insulanus) as an endangered species and designate critical habitat for the species under the Endangered Species Act (ESA).
The island marble, a beautiful, medium-sized, white butterfly with green ‘marbling’ on its wings, was historically known from southern Vancouver Island and the Gulf Islands of Canada. It went undetected for 90 years until being rediscovered in 1998 on San Juan Island, Washington. Despite subsequent ongoing conservation efforts, such as captive rearing and improving the butterfly’s prairie habitat, the butterfly is in danger of extinction. The small population size of the butterfly makes it especially vulnerable to threats, including habitat loss and predation.
“Only by working with our partners to ensure long-term habitat protection and management will the island marble butterfly survive the significant threats it faces,” said USFWS State Supervisor Brad Thompson. “Our dedicated partners in the San Juan Islands have enthusiastically embraced the conservation of this species, which is unique to these islands. I’m confident that with their continued support we will make great strides in recovering the island marble butterfly.” Partners in island marble butterfly conservation include multiple federal and state agencies, university and non-governmental partners, landowners, and the general public.
The Washington Department of Fish and Wildlife, in coordination with the USFWS, has developed a programmatic Candidate Conservation Agreement with Assurances (CCAA) to assist in recovery and to benefit local landowners. The CCAA will provide landowners and San Juan County with the opportunity to voluntarily create and maintain habitat for the conservation of the island marble butterfly while gaining ESA protections should their routine land management practices accidentally kill or injure the soon-to-be protected butterfly.
The Service is also finalizing the designation of approximately 813 acres of occupied critical habitat for the island marble butterfly. These lands are more than 90% federally owned, approximately 5% state owned, 4% county owned, and less than 0.5% privately owned. The great majority of federal lands included in the designation fall within San Juan Island National Historical Park.
The notice of the final rule will be available on the Internet at http://www.regulations.gov/.
To learn more about management activities and conservation of the island marble butterfly visit: www.fws.gov/wafwo.
The U.S. Fish and Wildlife Service works with others to conserve, protect, and enhance fish, wildlife, plants, and their habitats for the continuing benefit of the American people. For more information, visit www.fws.gov/pacific, or connect with us through any of these social media channels at facebook.com/USFWSPacific, flickr.com/photos/usfwspacific/, tumblr.com/blog/usfwspacific or twitter.com/USFWSPacific.
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