Monarch Butterfly
Family: Pieridae
The well-known monarch butterfly is frequently seen in the Sacramento region. Its orange-brown wings are bordered and tipped with black. The black areas of the wings and body are dotted with white spots. The wing span is 3 1/2 to 4 inches.
Pale green, ribbed eggs are laid on leaves and stems of milkweed plants. The caterpillars are yellow-green decorated with black and white bands. Black antennae-like filaments which extend from each end twitch when the caterpillare is disturbed. The chrysalis is a beautiful pendant resembling a small green lantern with gold spots. It is suspended head down by a delicate stem.
Large numbers of monarchs migrate southward in the fall. Some fly as far as South America; others gather in sheltered trees along the California coast. Unlike most other butterflies which die soon after mating, over-wintering monarchs return to the same area that they left the previous fall.
The relationship between the milkweed butterflies and their host plants is a classic example of the interdependence between animals and plants. The larvae are completely dependent upon the milkweed species for food. The plants have developed flowers which are specialized for butterfly pollination.