The Very Hungry Caterpillars

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We are raising caterpillars into butterflies.  Painted Ladies, to be exact. We’ve done this before, but this time we are really paying attention, every single day, to these fantastic creatures and the amazing transformation they are making. In just 9 days, they arrived at our house, grew tremendously and went into the chrysalis state. Here’s a closer look at that process.

Day 1: The caterpillars arrived about 10 days from hatching from the egg stage. They measured 1.5 to 2 cm.

Day 1 (10 days old)

We set up a caterpillar observation area where we could make daily observations and learn more about the caterpillars. The area contains the cups the caterpillars arrived in (they basically live with their food, a human-made concoction that looks a little like cookie dough).  The Observation Area also contains a clipboard with paper and pen for recording observations, some reference books about caterpillars and butterflies, a magnifying glass, a ruler, and these scientific method cards.

Day 4 (13 days old): The caterpillars have grown! They measure 2.5 cm now. They grow every day. There is less food in the container and something resembling spider web silk has appeared.

Around Day 4, we notice little, black, fuzzy parts of the caterpillars seem to be falling off. We consult with the breeder and she tells us that this is sort of like a snake shedding it’s skin. The kids note that the food is getting more crumbly.

Day 5 (14 days old): The caterpillars measure 3-4 cm! Many have moved to the top of the container, where they will soon hang in chrysalis form. They are bigger, fatter, longer than yesterday! They are moving slower.

On Day 5, we decide the caterpillars are not as fragile anymore so we gently hold one. This is also the day we discover that what we thought were crumbly bits of food, are actually pieces of caterpillar poop! It’s the same color as the food. Yuk!

Day 7 (16 days old): Some of the caterpillars in the “J” shape, which means they are ready to start forming their chrysalids.

On Day 7, we observe there are some red dots in the food. We wonder if this is mold. After lunch, we look at the caterpillars again. One has formed into a chrysalis! Just that morning he was a caterpillar hanging upside down from the coffee filter at the top.

By Day 8 (17 days old), each of the 5 containers has some chrysalids and some caterpillars.  But by Day 9 (18 days old), all are in the the chrysalis state. We make hypotheses on how long it will take them to hatch as butterflies.  Our guesses range from one week to one month.

Day 9 (18 days old): All of the caterpillars have entered the chrysalis state. All but one are attached to the coffee filters on the lid. One is in the food. We carefully lift him out with tweezers and transfer all the chrysalids to the butterfly house to await the next stage: hatching butterflies!

On Day 9 (18 days old), we measure the chrysalids.  They are all about 2 cm. Some of them are shaking and moving at different times. We pin the coffee filters containing the chrysalids to the sides of our mesh butterfly house. The one chrysalis not attached to the coffee filter is placed on the bottom of the mesh house.

Chrysalids in the mesh butterfly house.

And now we wait. We check. We wonder. We ask questions. “Why are they called BUTTER flies?”, The Queen Bee, age 6, ponders.  We look it up in Do Butterflies Bite?: Fascinating Answers to Questions About Butterflies and Moths . This is a great resource and it has answered many of the kids’ questions about the caterpillars so far. Incidentally, there are a few theories, but they might be called BUTTER flies because of the cream-colored and light yellow butterflies common across Europe.

Our Observation Area with the mesh container.

Love Bug (age 3) and The Queen Bee build a small fort with a blanket and chairs. They announce that this is a chrysalis. They pretend to eat a lot, then enter their chrysalis. They practice hatching and fly around like butterflies. They put music on and show me their butterfly dance.

The Butterfly Dance.

While we are waiting, we are checking the chrysalids each day and reading some terrific books:

Stay tuned for the next chapter of The Very Hungry Caterpillars when they hatch into butterflies. We will care for them, study them and then release them.

We got our caterpillars from a family member but my facebook readers tell me that Insect Lore  is a reputable brand, in the U.S.  In Canada, Canadian Home Education sells them.  Do any of my Australian and British readers have a resource for live caterpillars? What about other parts of the world? Please share in the comments. 

Linking up in these terrific places.