ABOUT MONARCH BUTTERFLIES

Monarchs can be divided into two, broad groups: the eastern and western populations. The eastern monarchs, the butterflies that are seen in Missouri, spend winter in central Mexico and breed east of the Rocky Mountains. The western monarchs spend their winters along the California coasts and breed in the Rocky Mountains. There is minimal interaction between the two populations.

Monarch butterflies undergo complete metamorphosis. This means they go through four distinct stages of development: egg, larva, pupa and adult butterfly. The entire metamorphic process, from egg to adult, takes about 30 days.

Adult monarchs live two to five weeks. This requires the insects to breed and lay their eggs at several locations during their summer migration. It takes several generations to finish the trip, meaning that the butterflies to leave Mexico are several generations removed from those that return.

Adult monarchs lay their eggs in the milkweed genus of plant and the caterpillars feed off the milkweed leaves. Without adequate amounts of milkweed, the butterflies have trouble surviving the long migration.

While monarch caterpillars will only eat milkweed leaves, adult butterflies can sustain themselves through a variety of nectar from native flowers.

Sources: Monarch Watch and Columbia Parks and Recreation Department