This has been a banner year for Monarchs in West-Central Indiana. After reports of diminished populations due to poor overwintering conditions in Mexico, the populations have rebounded and Monarch caterpillars can be found on most milkweed plants and much of the bindweed. An interesting project is keeping a Monarch as a pet to watch its extraordinary development.
The caterpillars grow very rapidly and consume a lot of food. If you decide to rear a caterpillar, you will need a source of fresh milkweed leaves. There are a few other plants that can serve as hosts, but milkweed is a certain host that is common, easily recognized and available. The top of a milkweed plant can be clipped and placed in a tall vase with a narrow opening. This will keep the leaves well hydrated. Hydration is important because the caterpillars must get all their water from the leaves. Caterpillars do not drink. Foliage should be checked for the presence of predators.
The caterpillars can be placed on the milkweed and more or less take care of themselves. Once they reach full size, they will curl into a C-shape and form a chrysalis, the pupa stage of the monarch. Monarch will sometimes attach to the top of a container and it is best to leave them in place. As the butterfly develops, you can observe some of the changes because the chrysalis is partly transparent. The wings forming inside the chrysalis will begin to take on their characteristic color shortly before the butterfly is ready to emerge. When the adult emerges, it splits the chrysalis open. The wings are moist and folded and must be extended. The butterfly pumps fluid through its wing veins to extend the wings with the help of gravity. It is important for the butterfly to rest vertically with its wings hanging down to get the full extension. A sturdy stick or stem will provide the monarch with the necessary perch.
Once the the butterfly wings are fully expanded, it is ready to fly away. Release it outside during the daylight and it will fly off in the direction of Mexico.
Top Left to Bottom Right: Milkweed, Young caterpillar, Caterpillar pre-molt, Early chrysalis, Chrysalis splits for emergence, Adult Monarch.