Range:
The yellow morphs of this species occur in British Columbia and Alberta,
south to eastern California and northern Arizona and New Mexico. They occur
through much of Idaho.
Habitat:
This species prefers open habitats, including fields, meadows,
sagebrush steppe,
and forest openings.
Diet:
Caterpillar:
Caterpillars eat the leaves of plants of the pea family (Fabaceae), such as
milk vetch (Astragalus spp.) and lupines (Lupinus spp.).
Adult:
Butterflies drink flower nectar.
Ecology:
There is only one generation of caterpillars each year. The
caterpillars overwinter in a physiological state called diapause, and emerge in the spring
to pupate. Adults generally
fly from mid-may to
September. Large numbers of adult males can frequently be observed congregating
at muddy sites where they obtain salt, a behavior called puddling.
Reproduction:
Males actively patrol
in search of receptive females. Females lay yellowish eggs singly on the topsides
of host plant leaves.
Conservation:
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Global Rank: |
G5; populations are widespread, abundant, and secure. |
Opler, P. A., H. Pavulaan, and R. E. Stanford. 1995. Butterflies of North America. Jamestown, North Dakota, USA: Northern Prairie Wildlife Research Center Home Page. http://www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/bflyusa.htm (Version 05Nov98).
Opler, P. A. and A. B.Wright. 1999. A Field Guide to the Western Butterflies. Second Edition. Peterson Field Guide Series. Houghton Mifflin Company, New York, New York, USA, 540 pp.
Pyle, R. M. 1981. National Audubon Society Field Guide to North American Butterflies. Alfred A. Knopf, Inc., New York, New York, USA, 924 pp.
Scott, J. A. 1986. The Butterflies of North America. Stanford University Press, Stanford, California, USA, 583 pp.
Stanford, R. E. and P. A. Opler. 1993. Atlas of Western U.S.A. Butterflies (Including Adjacent Parts of Canada and Mexico). Published by authors, Denver, Colorado, USA, 275 pp.