Callahan and Champagne explain the transition from caterpillar to chrysalis.
By Amelia Tarallo
Hometown Weekly Staff
Each year, monarch caterpillars transform from eggs to butterflies, all within a matter of weeks. This year, for her Girl Scout Gold Award project, Catherine Callahan decided to research these beautiful butterflies, raise them, and then release them. On Wednesday, September 25, Callahan visited the Medfield Public Library alongside her mentor Madeline Champagne to talk about monarch butterflies.
Before Callahan began her presentation, members of the audience wandered over to the nearby tank, where a few cocoons hung from the lid. Shortly before, the caterpillars in the tank had begun their metamorphosis and enclosed themselves in cocoons, where they will remain for around ten days.
Callahan began her presentation by pouring a few celery seeds into each audience member’s hands. These seeds are about the same size as a monarch butterfly’s eggs. When they emerge from the egg, the young caterpillars are tiny. “They’re as close to your thumb and index finger can get without touching,” said Champagne. The caterpillars eat milkweed and thrive until it’s time for them to go into their chrysalis.
Callahan brought out some chrysalises from butterflies that had hatched a few weeks before. “I thought you put glitter on them!” exclaimed one child after spotting the specks of gold coloring at the top of the jade green chrysalises.
After explaining about how caterpillars turn into butterflies, Callahan moved on to describe the migration of the butterflies. “Nobody knew where they went until the 1970s,” said Champagne. It was then that a scientist studying monarchs found a way to attach tiny tracking devices to them. It was then that scientists realized that these butterflies travel from as far as Canada to the mountains of Mexico. Callahan handed each person a picture of clusters of trees, each one covered in monarchs. “Are those really all butterflies?” one kid asked. His mom nodded.
Finally, the kids were directed to the craft room for the last part of the presentation. There, each child had the choice to make either a butterfly or a caterpillar craft. “It would be really cool if we could make a chrysalis, too,” one kid observed as she constructed her paper butterfly.
With this program, library visitors learned all about how they can help monarch butterflies and allow them to thrive here in Medfield. Though many monarchs are currently making their migration to Mexico, there are still some chrysalises waiting to hatch at the Medfield Library.