This species ranges from southern British Columbia south to southern California, Arizona, and New Mexico, and continuing south into Mexico. It extends east as far as central Montana, northwestern Colorado, and in isolated sections of Wyoming. It occurs through most of Idaho.
It can be found in a wide variety of habitats, including meadows, fields, disturbed areas, open woodlands, marshes, mountains, and canyons.
Caterpillars feed on the leaves of native and alien thistles, including
species of Cirsium, Silybum, and Carduus.
Adult: Butterflies drink flower nectar.
There are many generations of caterpillars each year through most of its range. Young caterpillars may live together in small silk webs. Caterpillars of the years last generation overwinter in a physiological state called diapause. Adults generally fly from April through October in most of its range. Butterflies tend to remain in the same general vicinity, near a particular group of flowers, for example, for several days in a row.
Males perch or actively patrol in search of receptive females. Females lay groups of off-white eggs on the undersides of thistle leaves.
|Idaho Status:||Unprotected nongame species.|
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.