STEAM: Butterfly Observation

Hi Friends,

I don’t know if you remember, but last summer I got to take care of caterpillars. They came from my librarian friend Miss Lindsey’s garden. 

I asked her to share what she did to take care of them so you and your family can enjoy butterflies too. She was happy to share and teach me a little about butterflies. Did you know…

  • There are 157 species of butterflies in Michigan.
  • Butterflies go through a series of metamorphosis. They go from egg to caterpillar to chrysalis to butterfly. Moths form cocoons, not butterflies.
  • Most caterpillars can only eat a specific type of food. These are called “host plants.”
  • Caterpillars are eating machines and can eat 200 times their body weight before forming a chrysalis. Sometimes they will even eat each other!

The most important thing to know about attracting butterflies is what host plants they need for their eggs. My caterpillars were Black Swallowtails and they ate parsley, fennel, rue, dill and carrot tops. Miss Lindsey planted fennel next to flowers like zinnia, daisies and calendula. The butterfly took breaks while laying eggs to visit the flowers. Keep reading to learn how you and your adult can take care of butterflies!

Your friend,

Thorndyke

Supplies

  • Host plants
    • Milkweed (Monarch butterflies)
    • Carrot, dill, fennel, parsley and/or rue (Swallowtail butterflies)
    • Lupine (Karner Blue butterflies)
    • Pearly everlasting, sunflower and aster (American Lady butterflies)
  • Pollinator-friendly plants
    • Calendula
    • Cosmos
    • Saliva
    • Zinnia
    • Beebalm
    • Coneflower
    • Daisy
  • Butterfly habitat cage or clean fish aquarium
  • Egg carton and plastic test tubes
  • Paper towels
  • Twigs/sticks

Tips

  • Caterpillars eat a lot. You will want at least three host plants to keep up with them, or you will run out of food.
    • Caterpillars will eat each other if they don’t have enough food or if they’re overcrowded. You can always start with as many as 12 caterpillars, but you’ll want to release all but four or five as they get bigger.
  • Start looking for the butterflies in your garden in late June and early July. Check the host plants frequently for tiny eggs or itty-bitty caterpillars.
  • When you find eggs or caterpillars, you can set up your habitat:
    • Place paper towel on the bottom for easy cleanup. Caterpillars poop a lot.
    • Arrange twigs/sticks to give caterpillars options for forming chrysalises.
    • Fill the test tubes halfway with water.
    • Put the egg carton upside down and place the tubes in the gaps.
    • Use scissors to cut stems or leaves from the host plant and place them in test tubes. The first cuttings should be the parts of the plant with the egg/caterpillar.
  • Replenish the food every other day. This will keep the food fresh and the caterpillars healthy. Eventually, you will need to replenish daily because they’re eating so much!
  • Swallowtail caterpillars expel green sludge right before they form a chrysalis.
  • Some butterflies “overwinter” in their chrysalises. This means the butterfly won’t emerge until next spring. Don’t assume that your butterfly has died.
  • Do not try to help a butterfly emerge from the chrysalis or touch it immediately after it has emerged. This will cause injury to the butterfly and will kill it.
  • Release the butterflies into your garden within a few hours of emergence so they can drink nectar and make the next generation of caterpillars!