A Green Hairstreak butterfly. Photo by gailhampshire, CC-BY.

An endangered butterfly, the Green Hairstreak Butterfly is isolated to three small parts of the city: Hawk Hill Park, Rocky Outcrop Park, and a small portion of the Presidio. Green Hairstreak larvae feed exclusively on the Coastal Buckwheat and conservation projects have focused on creating a corridor of these plants to "bridge" the three populations and prevent inbreeding.