Range:
Subspecies zephyrus ranges from southern British Columbia and Alberta
south to southern California, Arizona, and New Mexico, with isolated populations
in the western Dakotas and Nebraska. It occurs throughout most of Idaho. Subspecies gracilis ranges from central Alaska
south and east across southern Canada to Newfoundland and Nova Scotia, and does
not occur in Idaho.
Habitat:
It occurs in and along forests, in valleys, and along streams
and rivers.
Diet:
Caterpillar:
Caterpillars feed on the leaves of a variety of shrubs, including currant (Ribes
spp.), wild rhododendron (Rhododendron spp.), and mock azalea (Menziesia
glabella).
Adult:
Butterflies drink flower nectar, often from rabbitbrush (Chrysothamnus spp.),
and may obtain additional moisture and nutrients from sap and mud.
Ecology:
There is typically one generation of caterpillars each summer.
Caterpillars rest on the undersides of leaves. Butterflies emerge from chrysalises later in summer, and may
fly to higher elevations to feed. Returning back down in the fall, they then
overwinter in a physiological state called diapause until spring, when they emerge
to mate and lay eggs.
Reproduction:
Males perch to
wait for receptive females. Females lay eggs on the leaves and petioles of host plants.
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.