Monarchs are one of America’s favorite butterflies, and one of the most interesting. Here in Central Texas we are gifted with both summer monarchs, and huge numbers migrating in the fall. These interesting insects are also the state insect of Texas.
Migration is one of things that makes monarch butterflies so interesting. Most insects complete their life cycle very close to home, but monarchs are an exception. These butterflies migrate long distances to overwinter in Mexico and California. Monarchs, like other butterflies, go through four complete life stages; egg, larva, pupa and adult. Most butterflies overwinter in egg or pupa stages, but the monarch takes a different path. They complete three full life cycles during the summer months in North America, dying after they lay their eggs. Finally, they lay their eggs for a fourth time, emerge, pupate and become adults. These adults are the special ones that in September and October will make the long journey to Mexico, and overwinter in the adult stage. The migrating monarchs we see in the Austin area come from all over the central United States and Canada. In February and March, the monarchs end their hibernation, breed, and die. The newly hatched monarchs begin the journey north.
Another interesting fact about monarchs is their feeding habits and resulting nasty
taste to predators. Unlike some species of butterflies, monarchs are very picky about where they lay their eggs and live as caterpillars. Milkweed is the only plant where monarchs lay eggs and caterpillars feed. As they feed on milkweed, monarch caterpillars store up fat that is transferred to the pupa and adult stages. The chemicals in the milkweed sap are poisonous and taste nasty. Monarchs concentrate these chemicals in the fat as larvae making the monarch butterflies taste disagreeable to predators. The bright colors and pattern of the monarch signal to predators that they are not a tasty treat. Most predators only try a monarch once! Some other butterflies even imitate monarchs’ coloring to get the same predator protection.
Adult monarchs feed on just about any nectar producing flower. To attract these butterflies to your yard, plant milkweed for a host plant, and flowers for the adults to feed on.
We should be noticing many more monarchs in the coming weeks as they continue their migration to Mexico. By mid-October, in some Central Texas locations, we should be seeing hundreds a day. Keep your eyes out for these beautiful and unusual butterflies!