Famous for one of the longest insect migrations on Earth, traveling up to 3,000 miles from Canada to central Mexico each fall.

Also called: Wanderer

Native status: Native; vulnerable (IUCN 2022)

§ Quick facts

SizeWingspan 8.9–10.2 cm (3.5–4 in)
Weight~0.5 g
LifespanSummer generation: 2–6 weeks. Overwintering "Methuselah" generation: 6–8 months.
OrderLepidoptera
FamilyNymphalidae

§ Encyclopedia

The monarch butterfly or simply monarch is a milkweed butterfly in the family Nymphalidae. Other common names, depending on region, include milkweed, common tiger, wanderer, and black-veined brown. It is among the most familiar of North American butterflies and an iconic pollinator, although it is not an especially effective pollinator of milkweeds. Its wings feature an easily recognizable black, orange, and white pattern, with a wingspan of 8.9–10.2 cm (3.5–4.0 in). A Müllerian mimic, the viceroy butterfly, is similar in color and pattern, but is markedly smaller and has an extra black stripe across each hindwing.

Source: Wikipedia — Monarch butterfly Licensed under CC BY-SA 4.0

§ Identification

Field marks. Bright orange wings veined and bordered in black with white spots. Males have a black scent gland on each hindwing vein; females lack it.

Similar species. Viceroy (Limenitis archippus) — Müllerian co-mimic with a horizontal black band across the hindwing. Queen (Danaus gilippus) — darker, browner.

Voice. Silent.

§ Diet & behavior

Diet. Adults: flower nectar (milkweed, goldenrod, asters). Caterpillars: exclusively milkweed (Asclepias spp.) — toxic cardenolides sequestered for adult defense.

Behavior. The Eastern population undertakes a multigenerational migration — 3,000+ miles between Mexican overwintering colonies and Canadian breeding grounds. Western population overwinters along the California coast.

§ Range

Eastern: Mexico → Canada migratory; Western: California coast

§ Habitat

Open fields, gardens, prairies, and roadsides with milkweed and nectar sources

§ Threats

Loss of milkweed (only host plant for caterpillars), pesticide exposure, deforestation in Mexican overwintering sites, climate change.

§ Conservation status

According to the IUCN Red List, the monarch butterfly is currently classified as Vulnerable.

§ What helps

Plant native milkweed. Avoid pesticides in your garden. Support overwintering site protections in California and Mexico.

Support our work More ways to help

§ Further reading

§ Sources cited

  • Xerces Society
  • Monarch Watch
  • Journey North
  • IUCN Red List 2022
  • USFWS species status assessment