Range:
This species ranges from central Alaska, south through British Columbia and
Alberta, through the western U.S. to southern California, Arizona, and New Mexico.
It extends east as far as southeastern Montana, eastern Wyoming and western
Nebraska. It can be found throughout much of Idaho.
Habitat:
It utilizes a variety of habitats, including meadows, grasslands,
fields, forest openings, and swamps. It tends to be at low to mid-elevations
in the Rockies and at high elevations in the northwestern part of its range.
Diet:
Caterpillar:
Caterpillars feed on the leaves of asters (Aster and Machaeranthera
spp.).
Adult:
Butterflies drink flower nectar.
Ecology:
The number of generations of caterpillars each growing season
varies within its range, with only one in the north and at high elevations,
two to three in most of the range, and four in southern California. Caterpillars
feed in groups, often in a loose web. Young caterpillars present at the end
of the season overwinter in a physiological state called diapause; they emerge in spring to
continue feeding and molting,
and eventually pupate.
Adults generally fly
from May through September in most of its range.
Reproduction:
Males actively patrol
in search of receptive females. Females lay groups of pale green eggs on the
undersides of leaves of asters.
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.