Milkweeds are both host and nectar plants for the Monarch Butterfly (Danaus plexippus) and a closely related species, the Queen Butterfly (Danaus gilippus). The first picture shows them together, the Monarch on the left and the Queen on the right.
Monarch and Queen caterpillars hatch from tiny cream-colored eggs like the one seen in the picture. The caterpillars look similar but the Queen can be easily identified by a pair of thin projections (tentacles) at the head middle and tail ends of the body as seen in the picture. The Monarch Butterfly caterpillar only has tentacles on the head and tail ends. They eat nothing but milkweed and have evolved methods by which they avoid getting their jaws glued shut by the sticky sap. The caterpillars accumulate cardenoids from the plants in their bodies from eating the milkweed. These chemicals make the caterpillars and butterflies distasteful to predators and can also cause heart problems. After possibly consuming 175 to 200 milkweed leaves the Monarch caterpillar pupates into an opaque green chrysalis which turns transparent just before it emerges.
The famous migration of the Monarchs is quite complex. The round trip from Mexico to the northern US and Canada and back takes place over 4 generations and includes a southward migrating generation that can live up to 9 months. One of the ways the migration is studied is by tagging butterflies. The photo shows a tagged butterfly I found while visiting Maine in August of 2014. Monarchs that wander to South Florida usually stay there; and Monarchs living in South Florida do not migrate and have a normal life cycle of about 2 months. The Monarch Butterfly has become the focus of concern for the conditions, such as habitat loss, pesticide use and climate change, that are negatively impacting the populations of insects worldwide.
The notariety and appeal of the Monarch Butterfly makes it perfect for education because it has an amazing story and they are easy to grow throughout the year in Florida. The new Butterfly House will have an area where Monarchs and other native butterflies will be raised as an educational display and released to continue to delight us as we hike the trails.
