Monarch - Danaus plexippus
[From Ferris and Brown 1981; Scott 1986; Opler and Wright 1999; Glassberg 2001; Pyle 2002] Forewing 5.2-5.8 cm. Large, forewing long and drawn-out. Uppersurface with large orange ovals in tip of forewing, males bright orange with black scent patch in middle of hindwing, females duller orange with thicker black scaling of veins and no black scent patch; black border has two rows of tiny white spots; hindwing lacks black postmedian line.
Five or more flights, all year in California and southern Florida; several flights, March to November in New Mexico and southern Nevada; one or two flights, May to October (Scott 1986). Mainly March/April to October/November (Glassberg 2001); early June to early October in Oregon and Washington (Pyle 2002).
Distinctive; best told by color and large size, black border with two rows of tiny white spots, hindwing lacking black postmedian line.
In the New World, southern Canada and entire continental US south to South America, also many oceanic islands, overwintering in coastal California and Transvolcanic Belt of Mexico; naturalized in many other regions around the globe (Opler and Wright 1999; Glassberg 2001; Pyle 2002); to at least 3505 m elevation in Colorado, but usually below 2745 m (Scott and Scott 1978). In Montana, reported statewide (Kohler 1980; Stanford and Opler 1993). Common throughout the western range, except rare to uncommon in the Pacific Northwest (Glassberg 2001).
Observations in Montana Natural Heritage Program Database
Number of Observations:
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(Observations spanning multiple months or years are excluded from time charts)
Species overwinters in aggregations in coastal California and Mexico. In early spring individuals move northward over several flights to summer range. In late summer or fall a final flight moves south to overwintering sites (Scott 1986; Glassberg 2001; Pyle 2002). Majority of southward-moving individuals west of the continental divide probably overwinter in coastal California, southward-moving individuals east of the divide probably overwinter in central Mexico, but still little data to support this.
Open places, native prairie, foothills, open valley bottoms, open weedy fields, roadsides, pastures, marshes, suburban areas, rarely above treeline in alpine terrain during migration (Scott 1986; Opler and Wright 1999; Glassberg 2001; Pyle 2002). Reported in Glacier National Park, Montana in mesic montane meadows (Debinski 1993).
Larval food plants include Apocynum, several species of Asclepias (the primary host plant genus), Calotropis, Matelea, and Sarcostemma (Scott 1986, 1992, 2006; Guppy and Shepard 2001; Pyle 2002). Adults feed on flower nectar (including Achillea, Apocynum, Asclepias, Aster, Buddleia, Chrysothamnus, Carduus, Cirsium, Cleome, Conyza, Cosmos, Daucus, Dipsacus, Echinacea, Echinocystus, Eupatorium, Helianthus, Hesperis, Liatris, Lonicera, Machaeranthera, Medicago, Pastinaca, Phlox, Polygonum, Ratibida, Senecio, Solidago, Sonchus, Symphoricarpos, Syringa, Tagetes, Taraxacum, Trifolium, Verbena, Vernonia, Vicia, Zinnia) and mud (Scott 1986, 2014).
Females lay eggs (200 or more) singly under host plant leaves, stems, and inflorescences. Eggs hatch in about 6 days (depending on temperature). Growth rapid, to L5 and pupation in 18 days after egg-hatch. Adults emerge from pupae (eclose) in about 9-10 days. Larvae build no nests; L1-L2 instars hide in terminal shoots or under leaves, L3-L5 rest openly. Males patrol throughout the day near host plants in search of females; mating may occur at roost sites (Scott 1975b, 1986).
In a news release on December 15, 2020
the US Fish and Wildlife Service announced that after a review of available data on the species' status, the Monarch Butterfly warranted protection under the Endangered Species Act but listing was precluded by higher priority listing actions. The species is a candidate for listing and its status will be reviewed by the service on an annual basis. For more information on this species please visit the USFWS's Monarch Status Page
or Monarch web page
- Literature Cited AboveLegend: View Online Publication
- Debinski, D. 1993. Butterflies of Glacier National Park, Montana. Occasional Papers of the Museum of Natural History, the University of Kansas, Lawrence, Kansas. No. 159: 1-13.
- Ferris, C.D. and F.M. Brown (eds). 1981. Butterflies of the Rocky Mountains. Univ. of Oklahoma Press. Norman. 442 pp.
- Glassberg, J. 2001. Butterflies through Binoculars: A Field Guide to the Butterflies of Western North America. Oxford University Press.
- Guppy, C.S. and J.H. Shepard. 2001. Butterflies of British Columbia: including western Alberta, southern Yukon, the Alaska Panhandle, Washington, northern Oregon, northern Idaho, northwestern Montana. UBC Press (Vancouver, BC) and Royal British Columbia Museum (Victoria, BC). 414 pp.
- James, D.G. and D. Nunnallee. 2011. Life histories of Cascadia butterflies. Corvallis, OR: Oregon State University Press. 447 p.
- Kohler, S. 1980. Checklist of Montana Butterflies (Rhopalocera). Journal of the Lepidopterists' Society 34(1): 1-19.
- Opler, P.A. and A.B. Wright. 1999. A field guide to western butterflies. Second edition. Peterson Field Guides. Houghton Mifflin Company, Boston, Massachusetts. 540 pp.
- Pyle, R.M. 2002. The butterflies of Cascadia: a field guide to all the species of Washington, Oregon, and surrounding territories. Seattle Audubon Society, Seattle, Washington. 420 pp.
- Scott, J.A. 1975b. Mate-locating behavior of western North American butterflies. Journal of Research on the Lepidoptera 14:1-40.
- Scott, J.A. 1986. The butterflies of North America: a natural history and field guide. Stanford University Press, Stanford, California.
- Scott, J.A. 1992. Hostplant records for butterflies and skippers (mostly from Colorado) 1959-1992, with new life histories and notes on oviposition, immatures, and ecology. Papilio new series #6. 185 p.
- Scott, J.A. 2006. Butterfly hostplant records, 1992-2005, with a treatise on the evolution of Erynnis, and a note on new terminology for mate-locating behavior. Papilio new series #14. 74 p.
- Scott, J.A. 2014. Lepidoptera of North America 13. Flower visitation by Colorado butterflies (40,615 records) with a review of the literature on pollination of Colorado plants and butterfly attraction (Lepidoptera: Hersperioidea and Papilionoidea). Contributions of the C.P. Gillette Museum of Arthopod Diversity. Fort Collins, CO: Colorado State University. 190 p.
- Scott, J.A. and G.R. Scott. 1978. Ecology and distribution of the butterflies of southern central Colorado. Journal of Research on the Lepidoptera 17(2): 73-128.
- Stanford, R.E. and P.A. Opler. 1993. Atlas of western USA butterflies: including adjacent parts of Canada and Mexico. Unpubl. Report. Denver and Fort Collins, Colorado 275 pp.
- Additional ReferencesLegend: View Online Publication
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- Allen, T.J., J.P. Brock, and J. Glassberg. 2005. Caterpillars in the field and garden: a field guide to the butterfly caterpillars of North America. Oxford University Press.
- Brock, J.P. and K. Kaufman. 2003. Kaufman Field Guide to Butterflies of North America. Houghton Mifflin Company, New York, NY 284 pp.
- Caruthers, J.C., and D. Debinski. 2006. Montane meadow butterfly species distributions in the Greater Yellowstone Ecosystem. University of Wyoming National Park Service Research Center Annual Report, 2006. Vol. 30, Art. 14. 85-96.
- James, D.G. 2021. Western North American monarchs: spiraling into oblivion or adapting to a changing environment? Anim. Migr. 8:19-26.
- Layberry, R.A., P.W. Hall, and J.D. LaFontaine. 1998. The Butterflies of Canada. University of Toronto Press. 280 pp. + color plates.
- Maxell, B.A. 2016. Northern Goshawk surveys on the Beartooth, Ashland, and Sioux Districts of the Custer-Gallatin National Forest: 2012-2014. Montana Natural Heritage Program. Helena, MT. 114pp.
- Scott, J.A. 1982. Mate-locating behavior of western North American butterflies. II. New observations and morphological adaptations. Journal of Research on the Lepidoptera 21(3): 177-187.
- Western Monarch Working Group. 2019. Western monarch butterfly conservation plan 2019-2069. Western Association of Fish and Wildlife Agencies. Version 1.0. 109 p.
- Additional Sources of Information Related to "Insects"