Currently, there is only one known population of island marble butterfly (IMB), a species federally listed as endangered in may 2020

This single population is made up of approximately 200-500 individuals at SAN juan island national historical park in washington state. Presently, the national park service leads rearing efforts for island marble butterfly by collecting wild butterfly in their EGG and caterpillar life stages, rearing them in the lab for pupation, and then releasing them as adults. Island marble captive rearing is thought to have bridged a short-term, crucial GAP to prevent the extinction of this species and has continued as an annual effort to support the augmentation of the single known population of butterflies. While successful at stabilizing the island marble population to fend off immediate extinction, the captive rearing efforts of the national park service have been labor-intensive with limited output. Island marble butterfly recovery hinges on augmenting the single known population and producing butterflies and suitable habitat at a scale that reestablishes populations across the butterflys historic range. The current process is missing key program elements to provide continuity of practice, information transfer, and potential for scalability based on the butterflys recovery needs. A shift from annual efforts to a sustainable, long-term captive rearing program is a need identified by IMB partners to support the recovery of this butterfly. The first step toward this shift in establishing a long-term captive rearing program is to coalesce current information on the husbandry of the species and produce a comprehensive husbandry manual as a foundational document for the ongoing recovery of these species. WPZ staff are uniquely positioned with necessary butterfly husbandry background and expertise through their long-standing expertise in the captive rearing and release of the oregon silverspot butterfly and role as a consultant for IMB efforts. This project would address several priority 1 and priority 2 objectives identified in the species draft recovery plan and recovery implementation strategy, including: objective 4.1 develop and implement recommendations for improving existing facility and increasing rearing operational capacity. Objective 4.4 determine and document best methodology for reintroductions, translocations, and emergency translocations, including but not limited to lab and field triggers, to establish a new population(S) or augment the population(S). Objective 6.1 identify knowledge gaps and if gaps can be addressed through analysis of existing data and or new research. Objective 6.4 identify and develop recommendations for application of research results to recovery actions and activities. The proposed project will produce the following deliverables: the publication of an IMB rearing husbandry manual, a database for record keeping, and a suggested timeline for future revisions and updates, all in coordination with the USFWS. The proposed project will benefit the only known, endangered IMB population, as well as the national park service, U.S. Fish and wildlife service and other IMB partners.