Range:
This species normally ranges from southern British Columbia south to southern
California, and east to western Montana south to northern Mexico. It may also
migrate into the Midwest and parts of the northeastern U.S. In Idaho, it occurs throughout most of the state.
Habitat:
It utilizes a variety of habitats, including woodlands, chaparral, and forest clearings and
edges.
Diet:
Caterpillar:
Caterpillars feed on buck brush (Ceanothus spp.).
Adult:
Butterflies drink flower nectar.
Ecology:
There is generally one generation of caterpillars each year
in the northern part of its range, and up to three in the south. Adults overwinter
in a physiological state called diapause. In spring, they emerge to
mate and lay eggs. In those areas with multiple generations each year, as in
central California, adults from the first generation often migrate east and reproduce; their adult
offspring return in the fall to overwinter. Adult migration may also be triggered
by high Tortoiseshell densities and other environmental factors. Adults generally
fly from April to October.
Reproduction:
Males perch
to wait for receptive females. Females lay groups of eggs on buck brush (Ceanothus
spp.).
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.