Public invited to comment on WDFW recommendation to protect rare butterfly species

OLYMPIA – The Washington Department of Fish and Wildlife (WDFW) is seeking public input on a draft status report for the island marble butterfly that includes a recommendation to classify the butterfly as an endangered species in Washington. The public comment period is open from March 27 through June 25. 

“There is only one remaining population of island marble in Washington, occurring on San Juan Island,” said Taylor Cotten, WDFW conservation assessment section manager. “The population likely only remains viable due to captive rearing and augmentation efforts. This butterfly species is at high risk of extinction in our state.”  

In 2020, the island marble butterfly was classified by the U.S. Fish and Wildlife Service as endangered under the federal Endangered Species Act. WDFW’s draft species status report recommends also classifying the island marble butterfly as a Washington state endangered species. 

The draft status report for the island marble butterfly is now available on WDFW’s website. The public can submit written comments on the document via email or by mail to Taylor Cotten, Washington Department of Fish and Wildlife, P.O. Box 43141, Olympia, WA 98504-3200. 

Following the public comment period, WDFW staff will brief the Washington Fish and Wildlife Commission on the status report and recommendation. The Commission is tentatively scheduled to consider this topic in September 2025. 

The island marble butterfly (Euchloe ausonides insulanus), a subspecies of the large marble butterfly, is a medium-sized butterfly with a wingspan of approximately 1.75 inches. The subspecies can be most easily recognized by expanded marbling on its wings, which are covered with yellow scales and hair-like structures. The island marble butterfly was thought to be extirpated in Washington until its rediscovery in 1998 on San Juan Island. Today, the island marble’s range is restricted to a single complex of prairie, coastal dune, coastal bluffs, and lagoon habitats on San Juan Island. 

WDFW prepares status reports to recommend listing species as endangered, threatened, or sensitive in Washington. If a species is listed, WDFW prepares recovery or management plans to guide conservation and recovery efforts and periodically reviews the status of listed species in the state. More information is available on WDFW’s At-Risk Species webpage. 

WDFW works to preserve, protect, and perpetuate fish, wildlife, and ecosystems while providing sustainable fish and wildlife recreational and commercial opportunities.