The National Park Service acquired Fort Baker in 2001 from the United States Army and began working to improve the habitat of a petite periwinkle butterfly named the Mission blue. When congress passed the Endangered Species act in 1973, they were worried about charismatic mega fauna such as the brown pelican suffering from DDT pollution, or the Florida panther being crowded out by rampant urbanization. They were not necessarily thinking of butterflies or snails, or any of the flora that support the wildlife. Each species in a system represents a rivet in the makeup of a complicated machine like an airplane, and if too many rivets are removed the entire system can crash. As the father of ecology, Aldo Leopold wrote, “The first sign of intelligent tinkering is to keep all of the pieces intact.” The mission blue butterfly was one of the first invertebrates ever listed under the Endangered Species Act.

The mission blue butterfly’s entire adult life lasts about one week. The butterfly primarily spends this time looking for members of the opposite sex. Most of the mission blue’s year-long life cycle is spent in the caterpillar and pupae stage. During the flight season between March and June, the butterflies are actively mating in the coastal prairies of the Bay Area. They lay their eggs on the leaves and stems of three species of small lupines that grow in the grasslands, especially the silver-leaf lupine. Larvae hatch from the eggs after a few days and begin feeding on the lupine. The caterpillars then go dormant in the leaf litter beneath the plants until the following Spring, when the cycle begins again.

Park Service staff have been making things a little easier for the butterfly by removing invasive vegetation that had been eating up the grasslands where their host lupines grow. Volunteers have gone after French broom, jubata grass, fennel, and thoroughwort. They have also planted tens of thousands of lupines, grasses, and other wildflowers. Natural Resources Management has also partnered with the Fire Management program to remove invasive trees and to stabilize banks after a wildfire charged through the site in 2005. The Park Service has also been monitoring the butterflies to get a sense of population trends and whether the restoration project is boosting the butterfly numbers. Between 2001 and 2005 there were over 200 mission blue butterfly sightings. Butterfly populations naturally fluctuate from year to year based on weather patterns and the availability of their host lupines.

Educating the public about the struggling butterfly has been one of the most important aspects of the project. Signage, brochures, and ranger walks have been created around the story of this engaging insect. As a past president of the California Native Plant Society, Pete Holloran said, “Ultimately our success must not only be a biological one, but a social one. If we can get the message out about rarity and extinction, about how to slow down and look around, then we’re doing our job. We want people to engage with the land so that we don’t continue to lose species.”