U S Fish and Wildlife Service


Past Featured Pollinators:
  Allen's Hummingbird
  Buff-bellied Hummingbird
  Calliope Hummingbird
  Costa's Hummingbird
  Crested Honeycreepers
  Dakota Skipper
  El Segundo blue butterfly
  Karner blue butterfly
  Lesser long-nosed bat

Mexican long-nosed bat

  Mitchell’s Satyr
  Monarch Butterfly
  Rufous Hummingbird
  Rusty patched bumble bee
  Taylor's checkerspot butterfly
More Pollinators:
  Fringed Orchids and Hawkmoths

Fun Fact:

This is a very small butterfly, only about the size of your thumbnail! Despite this, so long as there is buckwheat, this little fighter is expected to stick around.



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El Segundo blue butterfly

image of an El Segundo blue butterfly
El Segundo blue (photo: Stonebird CC BY-NC-SA 2.0)

The range of the El Segundo blue butterfly (Euphilotes battoides allyni) historically extended over much of the 3,200 acre El Segundo Dunes of Los Angeles County, CA. The butterfly occupied areas within the dunes with high sand content and where its host plant (food plants for larvae), coast buckwheat (Eriogonum parvifolium), was found. The historic population size likely averaged 750,000 butterflies per year. The El Segundo blue is endemic to coastal sand dunes and is now found in this habitat in Los Angeles County extending from the Palos Verdes Peninsula north to the Ballona Wetlands. Since its listing as endangered, the El Segundo blue has also been found in Santa Barbara County, California.

image of coast buckwheat.
Coast buckwheat (photo: Alan Schmierer CC0 1.0)

The life cycle of the El Segundo blue butterfly is closely tied to coast buckwheat. Survival of each of its four life stages (egg, larva, pupa, and adult) depend on this plant. Adults normally fly from mid-June until early September but may emerge earlier. Adult butterflies typically live from four days to two weeks and feed on coast buckwheat pollen and nectar. Female butterflies mate and lay eggs on coast buckwheat flowers. Eggs hatch within three to five days, and larvae (caterpillars) undergo four instars (time between molts). Larvae then pupate in leaf litter, sand, or at the base of a leaf forming a pupa (chrysalis). This butterfly hibernates through winter as a pupa.




image of an El Segundo blue butterfly on coast buckwheat flower.
El Segundo blue butterfly on coast buckwheat flower (photo: Eric Porter/USFWS)

Threats to this butterfly are numerous. The Los Angeles coastal prairie has been converted to an urban landscape and the dunes are significantly reduced in size and quality. Restoration efforts were initiated in the 1980s and continue to this day. The largest population was protected from development in 1990, and despite dense residential and commercial development in coastal Los Angeles County, patches of suitable and potential habitat remain protected from development, and butterflies appear capable of finding these patches and thriving. Governmental development, especially by the City of Los Angeles and the Los Angeles International Airport is still a significant threat. In Santa Barbara County, the butterfly's habitat is also threatened by veldt grass (Ehrharta calycina), an invasive grass that spreads rapidly and can choke out native vegetation like coast buckwheat. Biologists are working to find effective treatments to remove and control the spread of the non-native grass.

Last Updated: June 17, 2019
June 17, 2019