NatureMapping Animal Facts

Monarch Butterfly


Monarch Butterfly  Danaus plexippus (Linnaeus, 1758)

Monarch butterfly Description: The upper side of a male Monarch is bright orange with wide black borders and black veins, while the hindwing has a patch of scent scales (see photo). The upper side of a female Monarch is orange-brown with wide black borders and blurred black veins. Both sexes have white spots on the borders and apex.

How big are they? Wing span: 3 3/8 - 4 7/8 inches (8.6 - 12.4 cm)

How do monarchs breathe? We breathe air into our lungs. Special red blood cells pick up the oxygen, and the arteries of our circulatory system carry the oxygen to the rest of our body. Unlike people, butterflies don't have lungs. Monarchs breathe through tiny openings on the sides of their bodies called spiracles. (The spiracles are in their cuticle, like our skin). The holes open into a system of tubes in their body (called trachea) that carry the oxygen all over their bodies.

Range / Habitat The Monarch ranges from Southern Canada south through the United States, Central America, and most of South America. Monarch are also present in Hawaii, Australia, and the Pacific Islands. Monarchs are found in eastern Washington, where they feed on milkweed plants.

Monarchs can be found in open habitats including fields, meadows, marshes, and along roadsides.

Monarch butterfly Diet: Monarchs feed on nectar from milkweeds. Early in the season before milkweeds bloom, Monarchs visit a variety of flowers including dogbane, lilac, red clover, lantana, and thistles. In the fall, adults visit composites including goldenrods, blazing stars, ironweed, and tickseed sunflower.

Caterpillars feed on milkweeds that contain poisons that are distasteful to birds and other predators. After tasting a Monarch, a predator learns to associate the bright warning colors of the adult or caterpillar with an unpleasant meal, and avoid eating Monarchs in the future. (source: Butterflies and Moths of North America)

Migration: East of the Rockies, Monarchs make a 3,000-mile journey each year, migrating between Canada and Mexico. These Monarchs return each winter to roosts in the hills of Michoacan, Mexico, where they gather by the millions.

Many people do not realize that over a million Monarchs also make a western migration. Monarchs west of the continental divide overwinter along the coast of California and breed on milkweed as far north as Washington and British Columbia. Although the winter roosts are not as large as their Mexican counterparts, these special places can host tens of thousands of beautiful Monarch butterflies. Unfortunately, many of these roosting sites are threatened by development and loss of the trees that create the unique conditions required by these butterflies.

How far do they fly in one day? Although, we don't know for certain, there was one tagged monarch that was recaptured 265 miles away from where it had been released the previous day!

Conservation: Monarch overwintering sites in California and Mexico should be protected and conserved to promote the long-term survival of this migrating species.

Learn about the California Monarch Butterfly Conservation Campaign.


Did you know?
  • Monarchs become toxic to birds by feeding on milkweed plants.
  • Adult Monarchs make massive migrations from August-October, flying up to 3,000 miles south to hibernate along the California coast and in central Mexico.
  • At the Mexico wintering sites, Monarchs roost in trees and form huge aggregations that may have millions of individuals.

Monarch butterfly Monarch butterfly

Male Monarch Butterfly feeding on nectar.

Monarch butterfly

Monarch Silhouette

More Information about Monarchs

California Monarch Butterfly Conservation Campaign
Monarchs west of the continental divide overwinter along the coast of California and breed on milkweed as far north as British Columbia. Visit this website to learn about conserving this beautiful species.

Journey North: Monarch Butterfly
Journey North engages students in a global study of wildlife migration and seasonal change. K-12 students share their own field observations with classmates across North America. They track the coming of spring through the migration patterns of monarch butterflies, bald eagles, robins, hummingbirds, whooping cranes and other wildlife.

Monarch Butterfly FAQ: Frequently Ashed Questions >>

Monarch Watch
Monarch Watch is an educational outreach program based at the University of Kansas that engages citizen scientists in large-scale research projects. This program produces real data that relate to a serious conservation issue. Monarch Watch gets children of all ages involved in science.

Animal silhouettes available to purchase »


Photo credits: photos © 2006 Tim Knight

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