Handbook of Nature-Study · Lesson LXXI · Topic 9: Butterflies and moths
71. The monarch butterfly
Goal: Your child can tell a monarch from other butterflies, find its caterpillar on milkweed, and explain why birds leave it alone.
You'll need
- A patch of milkweed (roadsides, meadows, gardens)
- A clear jar or mesh box and fresh milkweed leaves (optional)
- A hand lens (magnifying glass)
- A nature notebook and a pencil (colored pencils if you have them)
What's in the book
Comstock's story of the monarch: its slow, gleaming flight, its northward spread with the milkweed each year, its bad taste to birds, the viceroy that imitates it, and its beautiful green-and-gold chrysalis. Then Lesson LXXI with questions on the butterfly, the caterpillar and the chrysalis, and the poem "A Butterfly at Sea".
The lesson, step by step
When and where
Late summer and September, on milkweed. Comstock's method: give the lesson in September, "while yet the caterpillars of the monarch may be found feeding upon milkweed." Look on the undersides of leaves for black, yellow and white striped caterpillars.
Safety first
Milkweed's white sap is sticky and stings if it gets in the eyes. Don't rub eyes, and wash hands after touching the plant. If you keep a caterpillar, give fresh leaves daily and let the butterfly go on the day it comes out.
Keep the big idea in mind
Comstock's "leading thought" is the one idea the lesson is meant to lead to. Read it to yourself now, and save it to share at the end, after your child has looked and answered:
The monarch butterfly migrates northward, every spring and summer, moving up as fast as milkweed appears, so as to give food to its caterpillar; and it has often been noticed migrating back southward in the autumn in large swarms. This insect is distasteful to birds in all its stages. Its chrysalis is one of the most beautiful objects in all nature.
The butterfly
How can you tell the monarch butterfly from all others? What part of the wings is red? What portions are black? What portions are white?
Is the flight of the monarch rapid or slow and leisurely? Is it a very showy insect when flying? Are its colors more brilliant in the sunshine when it is flying than at any other time? Why is it not afraid of birds?
Is there on the butterfly you are studying, a black spot near one of the veins on each hind wing?
That spot shows it is a male; females don't have it.
The caterpillar
Where did you find the Monarch caterpillar? Was it feeding below or above on the leaves? Describe how it eats the milkweed leaf.
How many whip-lash shaped filaments do you find on the caterpillar? On which segments are they situated? Do these move when the caterpillar walks or when it is disturbed?
The chrysalis
If you keep a caterpillar, or find a chrysalis on a plant or fence:
Describe the chrysalis. What is its color? How and where is it ornamented?
After three or four days, how does the chrysalis change in color?
Look for the tiny gold dots with the hand lens.
Put it into words
Ask why a monarch can fly slowly in the open when other butterflies dodge and hide. Then read the leading thought aloud.
Nature notebook
Paint or color a monarch with the wings open, showing the black veins and white dots, and beside it the green chrysalis with its gold dots. Add the date and the plant where you found the caterpillar.
Afterwards
Comstock asks: "Do you know of any other butterfly which imitates it and thus gains an advantage?" Look for the viceroy, which looks like a smaller monarch with an extra black line across each hind wing.
Tip
What we know now: in the 1970s scientists found where the eastern monarchs go: in fall they fly all the way to mountain forests in central Mexico, where millions spend the winter together. Scientists have also found that viceroys taste bad to birds too, so the two butterflies warn birds together.