Quick, what has six legs, four wings and is an international traveler that doesn’t need a passport? Need another hint? What starts out as a tiny spherical egg and goes through more physical changes in its appearance than Michael Jackson. Ok, this is too fun, just one more. What is capable of flying thousands of miles yet weights less than one ounce. I’m sure by now you have figured out I am talking about the Monarch Butterfly (Danaus plexippus)

The Monarch Butterfly is one of those truly amazing critters in nature. An amazing marvel of ability and determination in a small package. It starts out as a tiny white egg on the underside of milkweed leaf no bigger than the head of a pin. From this emerges a tiny green, yellow and black caterpillar and its first order of business is to eat its own egg shell. From that its moves onto eating the very leave where the egg was attached. You see, the female monarch is very specific as to where she will lay her eggs. She flits about landing on different plants. At best we can tell, once she lands on a leaf she rapidly taps her two front feet on the leaf in a drumming action. Presumably the leaf gives off an odor or chemical that the female picks up by her antennae to tell her if she is on the right plant or not. If she is she will deposit a single egg on the underside of the leaf. She will repeat this over and over again until she had laid dozens of eggs.

As the tiny caterpillar feeds, it grows quickly. In fact at this stage of life that is all it does is eat. It takes less than two weeks to eat enough to grow large enough to become an adult caterpillar. The green leaf it feeds on is one of the milkweed family. This is a highly specialized group of plants that all contain a milky sap in the leaves and stems. The sap contains toxic chemicals called cardiac-glycosides. The effects on a bird or mammal that eats it is rapid heart rate, nausea and vomiting. However the Monarch assimilates the chemical into its body and doesn’t have any side effects.

When the caterpillar can grow no more, it enters a new life stage. Positioning itself so it can hang upside down on a twig or branch the Monarch caterpillar attaches itself at the tail and freely hangs head side down. Shortly after moving into the hanging position the skin of the caterpillar splits open and peals down the back revealing a green sack, called a chrysalis, ornamented with gold dots. Inside the sack all of the caterpillars cells liquefy and rearrange forming the soon to emerge butterfly. In just over a week the butterfly is fully formed and ready to emerge from the chrysalis and complete the last stage of life.

At this point the chrysalis splits open and the fully formed Monarch butterfly emerges. And if that wasn’t interesting enough the life of the butterfly compared to the caterpillar and chrysalis is truly amazing. At the end of summer a special generation of Monarch butterfly adults prepares to migrate south. There are several migratory insects but the Monarch is the only one that travels across international borders and also migrates to and from a set destination at a specific time of year. All of our Monarchs in Eastern US will migrate to the Mountains of Mexico where millions of Monarchs over-winter by cling to the leaves of trees high up in the mountains of Mexico.

Early in spring the Monarchs leaves Mexico and start their journey north into the US. Along the way the females mate and begin laying eggs on Milkweeds in the southern states. This is as far as this generation of Monarchs will make it. They will die but their eggs will hatch leaving this generation to continue flying northward. Along the way they will also mate and lay eggs. Depending upon where you live it may take several generations for the butterflies to return and everything starts all over again. Talk about amazing. Until next time

Stan Tekiela is an author / naturalist and wildlife photographer who travels the US to study and photograph nature. He can be contacted via his web page at www.naturesmart.com