Range:
This species ranges from eastern Alaska and the Yukon Territory across Canada
to southern Quebec; in the U.S., it ranges from Washington along the Rockies
to northern New Mexico. It also occurs in central California and in parts of
Utah, Nevada, and the Great Lakes region. It can be found through much of Idaho.
Habitat:
It occurs in a variety of habitats, including tundra, forest openings, meadows, northern prairies, and rocky slopes.
Diet:
Caterpillar:
Caterpillars feed on select grasses (Poaceae) such as poverty oat-grass
(Danthonia spicata) and Idaho fescue (Festuca idahoensis).
Adult:
Butterflies drink flower nectar. They are often found "puddling" at muddy seeps where
they gather salts and nutrients by sipping moisture.
Ecology:
There is one new generation of caterpillars each summer in most locations. Young caterpillars overwinter in a physiological state called diapause. They emerge in spring to feed and molt, then enter diapause again for a second winter, this time as grown or nearly grown caterpillars. The process can be synchronized in certain populations, resulting in the appearance of adults only every other year in some locations. Adults generally fly from the first of May through August.
Reproduction:
Males perch to wait for receptive females. Females lay eggs singly on grasses (Poaceae).
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.