Information on Smith's Blue Butterfly

Discovery

• In 1948, Rudi Mattoni and Claude I. Smith, two undergraduate students at U.C. Berkeley, were on a trip to Big Sur. While there, Mattoni captured a never-before-seen butterfly. When Smith died in a fishing accident several years later, Mattoni named the new butterfly after the friend who had been there for its initial discovery.

Description

• Smith's blue butterflies are small, measuring only about 1 inch across. The Xerces Society describes the male as having a "bright lustrous blue" color on the back of its wings. The females are plainer: "brown with a band of red-orange marks across the hind wings." The underside of both sexes appear "whitish-gray, speckled with black dots and with a band of red-orange marks crossing the hind-wings near the outer edge."

Life Cycle

• The Smith's blues have a short life span--only about 1 week. According to Los Padres Forestwatch, they are active from June through September, coordinating with the blooming season of the buckwheat plants on which they depend. Adult butterflies feed on nectar from the buckwheat flowers, which also host the single egg laid by the female. When the egg hatches, the caterpillar feeds on the flowers and, after about a month, forms a chrysalis on the buckwheat. After 47 weeks of dormancy, the cycle begins again.

Habitat

• The Xerces Society notes that Smith's blue butterflies exist only in the sand dunes and cliff/chaparral areas of the central California coast, specifically in Monterey, Santa Cruz and San Mateo counties. The entire life cycle of the insects revolves around the Coast and Seacliff buckwheat plants found in these areas. In fact, Dave Dixon, writing for the U.S. Fish &Wildlife Service, explains, most of the butterflies will never fly more than 200 feet from the plants.

Threat

• A number of factors threaten the future of the Smith's blue butterflies. Los Padres Forestwatch explains that invasive plants such as ice plant and European beach grass "smother" the buckwheat on which the Smith's blues depend. Forestwatch also points to grazing commercial livestock, which crush the plants and destroy the chrysalises. Dixon observes that "freeway building and urbanization" have already destroyed 50 percent of the butterflies' coastal dune habitat. He also notes that numerous other environmental stressors, including dune recreation and sand mining, have "adversely affected the [...] coastal dune ecosystem."