The Fender's Blue Butterfly was added to the endangered species list in January 2000, but as of February of 2023, has been reclassified as "threatened".

[5] The subspecies was first documented in the 1920s and was described to science in 1931 by biologist Ralph Macy, who named it for his friend, Kenneth Fender, an entomologist and mail carrier.

[13][12] As an adult it lives for no more than three weeks, during which time it mates, feeds, and the female seeks Kincaid's lupines on which to oviposit.

[15] Fender's blue butterfly has been observed to participate in facultative mutualism with several species of ant, including Prenolepis imparis and Aphaenogaster occidentalis.

[17] Fender's blue butterfly is endemic to the Willamette Valley in Oregon, where its habitat is fragmented into 13 sections.

[18] The movement patterns of butterflies were tracked in environments both with and without lupine to understand the impact of their surroundings on their spread rates.

By combining diffusion rates and total active flight hours, the potential distance Fender's blue butterflies could cover over their lifetime.

Previously, the Willamette Valley presented a mix of upland and wet prairies, with lupine patches typically not exceeding a 0.5-kilometer distance from each other.

[18] The increasing presence of anthropogenic structures, agriculture, and urbanization threaten habitat fragmentation, as roads can prevent movement and introduce mortality risk from vehicles.

[7] Fender's blue butterfly is a protected species in The Nature Conservancy's Willow Creek Preserve in Eugene, which extends into the Willamette Valley.

Fish and Wildlife Service proposed for Fender's blue butterfly to be downlisted to a threatened species to take effect on February 13, 2023.

[22] In October 2006, approximately 3,010 acres of land in Oregon was legally determined to be a protected habitat for Fender's Blue Butterfly.

[7] Various conservation agencies have also worked with private landowners, approximately 96% of the Willamette Valley, about utilizing their land for habitat restoration for Fender's blue butterfly.