A Naturalist’s Obsession
On my way to work this morning I spotted five monarch butterflies.
Although many monarchs are usually spotted on the Blue Ridge Parkway this time of year, my first sighting of the year took place on highway 321 at the Walmart intersection.
I had been looking for the butterflies for several weeks, knowing that their annual migration south should take them through our area in mid-September. And then there they were; small glimpses of orange hovering above the traffic in Boone.
This made me think of all the ways that I am amazed by the monarchs. I dedicate this week’s article to the little butterfly that could.
Why are you so obsessed with monarch butterflies? — Ex-roommate
Ex-roommate, I know it was hard for you to understand why I might have monarch posters, observation kits and monitoring tools. I apologize for the time that I woke you up during your prized naptime to watch a caterpillar metamorphose. And it goes without saying that caterpillar scat on the kitchen table was unacceptable.
However, I think I may be able to explain my interest, or “obsession,” here with five not so well-known facts about the amazing life of the monarch butterfly.
No. 1: Monarch butterflies and caterpillars taste really bad.
Monarchs depend on a particular plant, milkweed, for survival. Monarch caterpillars will not eat anything else, so that is where the female butterflies lay their eggs.
The leaves of the milkweed are full of foul-tasting toxins that keep most animals from eating the plants. The caterpillars absorb these toxins when they munch on the leaves. In this way, the caterpillars and butterflies will sicken birds, lizards and mammals. Their bright coloring is a warning to predators.
I have never eaten a monarch caterpillar, but my dog did once. He regretted his decision immensely and in many ways.
No. 2: A chrysalis is not something that they wrap themselves in. The caterpillar becomes the chrysalis.
When the caterpillar has reached maturity it will hang upside down on a patch of silk and shed its caterpillar skin to reveal the chrysalis from within. The old skin falls away like a stretched-out wool sock.
No. 3: During the pupa phase, the monarch liquefies inside the chrysalis and reorganizes itself into a butterfly.
Need I say anything more?
No. 4: Monarchs are born with two tongues.
When the adult butterfly emerges from its chrysalis its tongue is split in half. It has about an hour to fuse together the two halves or it will starve. During this time, the butterfly must use microscopic muscles to interlock the pieces that will form its tubelike mouth, called a proboscis.
No. 5: Generation A.
Most of us know that the monarch butterfly migrates to Mexico for the winter. Did you know that monarchs are the only butterflies to make a two-way migration? This means that the same butterfly that migrates to Mexico also makes some of the journey back north.
We call the migrating butterflies, “Generation A.” Something is different about Generation A. Whereas most monarch butterflies only live for a few weeks, Generation A, which emerges from their chrysalises in late summer, will live for nine months.
They have never been to Mexico before, in fact it was their great-grandparent that made the previous year’s journey, but somehow they know that their survival depends on going south.
They fly 25 to 30 miles a day, on little wings, through big cities and rural farmland. Using the complex navigation equipment inside their pin-sized brains, they are able to find the same forest as their ancestors.
How can I not be obsessed by the little butterfly that could?
If you have a question concerning flora and fauna, please email (firstname.lastname@example.org) All of your questions will be answered. Two will be featured next week. See you on the trails.
Amy Renfranz is an interpretive park guide on the Blue Ridge Parkway. She is a certified naturalist through the Yellowstone Institute and a certified environmental educator in the state of North Carolina. Her comments are made independently and do not reflect the views of the National Park Service.