Monarch butterflies can be found throughout North America. They are notable for their annual southward migration in early fall, covering thousands of miles with many generations of butterflies among them. They fly from as far north as southern Canada and the United States down to Mexico, where they winter. Monarchs west of the Rockies will often migrate to California. They will generally start a return trip north in the early spring and arrive in their summer areas around July.
Monarch butterflies are milkweed butterflies, which means they lay eggs singly on the underside of the milkweed plant during the spring and summer. They can lay up to 1200 eggs and may mate several times. There are various caterpillar stages, they will molt about five times and with each molt they become bigger. They eat milkweed, which develops and increases their mass before going into the pupa stage. The last larval molt is how big they will become, they will then search for a site to secure themselves to, spin a silk pad into a horizontal sub-state to hang upside down, until they turn into chrysalis. Metamorphosis begins and they stay encased until the adult stage. They will emerge as an adult, continue to hang upside down until the wings are dry, then pump body fluids into the wings, which expand and stiffen until conditions allow them to fly. They then feed on nectar plants and water by using a sucking tube called proboscis that lies coiled under the head when not in use.
Monarch butterflies are very distinct with their orange and black wings. The male monarch has duller colors than the female. They can be seen gliding slowly with wings held at an angle. Their senses of smell and vision help to assess its environment and guide them throughout their daily lives. As adults they will live up to six weeks, where they will begin the cycle of life again by courting, mating, and laying eggs.