Lupinus sulphureus ssp. kincaidii (Kincaid’s lupine) and Icaricia icarioides fenderi (Fender’s blue butterfly) in the West Eugene Wetlands: Population monitoring, reintroduction success, and an evaluation of experimental treatments

This report documents research conducted on Kincaid’s lupine (Lupinus sulphureus ssp. kincaidii), a threatened species in the legume family. Kincaid’s lupine serves as an obligate larval host plant for the endangered Fender’s blue butterfly (Icaricia icarioides fenderi). Both species are endemic to western prairies. The specific objectives of this project are to 1) describe trends of Kincaid’s lupine and Fender’s blue butterfly eggs at sites managed by the Eugene District Bureau of Land Management in the West Eugene Wetlands (in 2010 Fir Butte and Oxbow West; previous monitoring efforts included Isabelle, Turtle Swale, and Dragonfly Bend), 2) evaluate mowing and burning as management treatments for reducing invasive weeds and enhancing Kincaid’s lupine and Fender’s blue butterfly populations, and 3) evaluate estimates of lupine foliar cover as an alternative to time-consuming leaf counts.