Endangered Status for the Island Marble Butterfly and Designation of Critical Habitat; Proposed rule.

We, the U.S. Fish and Wildlife Service (Service), propose to list the island marble butterfly (Euchloe ausonides insulanus) as an endangered species and designate critical habitat under the Endangered Species Act of 1973, as amended (Act). In total, approximately 812 acres (329 hectares) on the south end of San Juan Island, San Juan County, Washington, fall within the boundaries of the proposed critical habitat designation. If we finalize this rule as proposed, it would extend the Act's protections to this species and its critical habitat. The effect of this rule will be to add this species to the List of Endangered and Threatened Wildlife and to designate critical habitat for the island marble butterfly under the Act. We also announce the availability of a draft economic analysis (DEA) of the proposed designation of critical habitat for the island marble butterfly.