Image via WikipediaNext the grown caterpillar attaches itself head down by a dot of silk, sheds its skin for the last time and over the next couple of hours forms into a chrysalis. Green like a leaf, the pupa transforms itself in two weeks into a butterfly and emerges from the chrysalis.
Monarch Butterflies drink nectar from flowers and produce 3-4 broods of offspring per year. After about two weeks they die except for the last generation of Monarchs that hatch in September or October. These special butterflies migrate thousands of miles to their winter grounds in Mexico and live 6-9 months. When the weather begins to change these butterflies start to fly north, mate, and lay eggs. During spring migration north, a female monarch leaves a trail of eggs behind her as she travels. The eggs will become adult butterflies and complete the migration to Michigan later in the spring. They will be the offspring of the monarchs that spent the winter in Mexico.
Spring is a critical time for monarchs. Their numbers are at their lowest point at this time of year. The old generation is dying. A new generation must grow and survive. You can track their migration on the Monarch Butterfly Migration Map.
To learn more go to Journey North's Monarch Butterfly Booklets and Slideshows http://www.learner.org/jnorth/tm/monarch/jr/BookletList.html