Monarch Butterfly Danaus plexippus (Linnaeus, 1758)
What they look like: The upper side of a male Monarch is bright orange with wide black borders and black veins (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)
Where are they? The Monarch range 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.
Where they live: Monarchs can be found in open habitats including fields, meadows, marshes, and along roadsides.
What they eat: 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.
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?
photos © Tim Knight
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