Smith's Blue Butterfly

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Smith's Blue Butterfly

Euphilotes enoptes smithi

StatusEndangered
ListedJune 1, 1976
FamilyLycaenidae (Gossamer-winged butterfly)
DescriptionSmall butterfly; males are bright blue above, females are brown.
HabitatCoastal sand dunes.
Host PlantBuckwheat.
ReproductionFemales deposit eggs on buckwheat flowers.
ThreatsHabitat loss and disturbance.
RangeCalifornia

Description

Smith's blue butterfly, Euphilotes enoptes smithi, is slightly less than 1 in (2.5 cm) across. The male's upper wings are a lustrous blue with wide black borders; females are brown above with a band of red-orange marks across the hind wings. Both sexes have prominent checkered fringes on the fore and hind wings. Smith's blue butterfly can be distinguished from other subspecies by a light undersur-face ground color and prominent overlying black markings with a faint black terminal line. Smith's blue was formerly classified as Shijimiaeoides enoptes smithi.

Behavior

Adult butterflies feed, rest, sun, and mate on several species of buckwheat (Eriogonum ), never straying far from host plants. Males perch on flowers, sometimes seeming to watch for approaching females to court. Females deposit eggs individually on buckwheat flowers. Larvae hatch four to eight days later and go through five instars (intermediate stages) before pupating in flower heads or in the sand and litter at the base of the plants.

Pupation occurs between mid-August and early September, and pupae hang in place until adults emerge the following year. Males tend to emerge first; females follow about a week later, at which time courtship and copulation occur. The adult flight period from mid-June to early September corresponds with the blooming of the buckwheat plants. Each adult lives for only about one week, but individual emergences are staggered over the extended flight period.

Habitat

Smith's blue butterfly is found on coastal and inland sand dunes, which support buckwheat and associated species, such as Ben Lomond wallflower, California poppy, bicolor lupine, and ponderosa pine. The butterfly is also found on cliffside coastal sage scrub and serpentine grassland, where dominant grasses are intermixed with buckwheat and other forbs.

Distribution

The Smith's blue butterfly is an endemic California subspecies, found primarily along the coast from the mouth of the Salinas River to Del Rey Creek.

The current distribution of Smith's blue butterfly includes coastal portions of Monterey County. Although there is no current population estimate, the butterfly is now considered more abundant than at the time of federal listing due to the discovery of several new populations.

Threats

The Smith's blue butterfly's coastal habitat has suffered a number of disturbances. Dunes are threatened by proposed housing developments, road construction, beach recreation, and off-road vehicles. Some dunes have been invaded by the non-native iceplant and Holland dunegrass, which displace buckwheat. Sand dunes at Fort Ord have been damaged by military activities, and large dunes in the Seaside-Marina dune system have been destroyed by sand mining. Sand mining is also occurring in the Del Monte Forest.

Conservation and Recovery

In 1986 the Marina city council prepared a habitat conservation plan for the coastal dunes that lie between Fort Ord and the Salinas River in Monterey County. In 1977 the Army established a butterfly preserve at Fort Ord, and the Youth Conservation Corps has removed non-native plants and attempted to reestablish native plants there.

In 1987 Smith's blue butterfly was confirmed in remnant habitat at Sand City in Monterey County. Some of this dune area has been zoned for housing development, but the city agreed to complete a conservation plan before work proceeded.

Contact

Regional Office of Endangered Species
U.S. Fish and Wildlife Service
911 N.E. 11th Ave.
Portland, Oregon 97232
http://pacific.fws.gov/

References

Arnold, R. A. 1983. "Ecological Studies on Six Endangered Butterflies (Lepidoptera: Lycaenidae): Island Biogeography, Patch Dynamics, and the Design of Habitat Preserves." University of California Publications in Entomology 99:1-161.

Langston, R. L. 1963. "Philotes of Central CoastalCalifornia." Journal of the Lepidopterists' Society 17:210-223.

U.S. Fish and Wildlife Service. 1984. "Smith's Blue Butterfly Recovery Plan." U.S. Fish and Wildlife Service, Portland.