Monarch (Danaus plexippus)

TPWD ©

Other Names

Monarch Butterfly

Description

Adult monarch butterflies are orange above with black veins and white spotted wing borders. Males have a black scent patch on a vein across the middle of the hind wing.

Life History

Monarchs are the only butterflies known to make long distance migrations. They are members of a tropical family that cannot survive cold winters. North American monarchs migrate south in the fall to California, Mexico or Florida. On the way north in the spring they lay eggs. It's the young produced by those and the next generation's eggs that return all the way north and start south again.

Monarchs lay their eggs on milkweed plants. Female monarchs can lay between 400 and 600 eggs. Their caterpillars absorb the poisons produced by the plant and become poisonous themselves. Birds that try to eat monarchs or their caterpillars become ill. They quickly learn that monarchs are not good to eat. Other butterflies, such as Queens and Viceroys, copy the colors of monarchs so that birds won't eat them either.

Adults feed on flower nectar. Caterpillars feed on plant leaves, preferring milkweeds and dogbanes. Monarchs enter Texas in the fall weighing 400 milligrams but leave weighing 650 milligrams. This 62.5% increase in weight is stored in the form of fat which the butterflies will use as an energy source during cold weather.

Monarchs return by the tens or hundreds of thousands to the same groves of trees each winter. They are sluggish during the winter and feed only on warm days. Humans are trying to protect these important places by creating butterfly preserves. Researchers study monarch migration by tagging individual butterflies to see where, how far and how fast they travel.

Habitat

Monarchs occur wherever milkweeds grow.

Distribution

Monarchs are found all over Texas, the U.S., southern Canada and Mexico to central America. There are also breeding populations in Hawaii and Australia.

Other

Schools can be involved in monitoring monarch butterfly migrations by contacting:

Texas Monarch Watch Nongame Program
Texas Parks & Wildlife
4200 Smith School Road
Austin, TX 78744
or by calling 1-800-792-1112.