Federal wildlife officials want to protect a rare white and green marble butterfly found only on Washington’s San Juan Island.
The U.S. Fish and Wildlife Service on Wednesday announced that it is proposing to list the island marble butterfly as an endangered species and designate about 813 acres (329.02 hectares) of mostly public land on San Juan Island as critical habitat for them.
The island marble butterfly has been declining since it was rediscovered on the island in 1998 after decades of no documented sightings. Their small population makes them vulnerable to habitat loss and predation, the agency said.
The last remaining known population is in an area that is part of San Juan Island Historical Park. Surveys in 2017 found fewer than 200 adults.
“After years of delay, the Service must move quickly to implement conservation measures to reverse declines,” Scott Hoffman Black, executive director of the Xerces Society for Invertebrate Conservation, said in a statement.