Nursery turns its eyes to the island marble and Oregon silverspot butterflies

Butterfly populations in the Pacific Northwest are declining due to habitat loss, degradation,  and fragmentation. CNLM’s Conservation Nursery has been tapped by partners outside of the South Sound to provide host and nectar plants and seed that will be used to restore habitat for two rare butterflies on the Oregon coast and the San Juan Islands.

Oregon silverspot butterfly. Credit: USFWSThe Oregon silverspot, a sub-species of the Zerene fritillary, is a beautiful orange and black butterfly with distinctive silver spots on the underside of the wings.  Once common it is now found in just a few locations on the Oregon coast.  Reproduction of this silverspot is dependent on the presence of early blue violet (Viola adunca), a plant common in our South Sound prairies. CNLM will begin coordinating seed production of the coastal Oregon ecotype of this violet to support on-going recovery efforts.  The seed will actually be produced at the Washington Correction Center for Women in Gig Harbor through the dynamic Sustainability in Prisons Project.

Island marble butterfly. Credit: U.S. Fish and Wildlife Service.The island marble butterfly, a truly extraordinary insect, was thought extinct for a century before being spotted on the southern tip of San Juan Island in 1998. This population resides at American Camp, a portion of the San Juan Island National Historic Park.  Dr. Amy Lambert from the University of Washington has been working with biologist Jenny Shrum from the National Park Service to increase the population of this butterfly since its rediscovery.  The original host plants for the island marble were native mustards that may have experienced a phenological shift in the preceding 100 years, taking them out of sync with the butterfly’s reproductive cycle.  Now the primary host is the crop plant and agronomic weed field mustard (Brassica rapa), best known as the source of Canola oil. Initial recovery efforts have focused on increasing the abundance of field mustard but for the next phases of recovery several native bulbs and forbs will be required as nectar plants.  A contract is in the works with CNLM to produce these native nectar plants for the island marble’s recovery.