HENRICO COUNTY, Va. (WRIC) — Students at Henrico’s Gayton Elementary gathered to bid farewell to monarch butterflies born and raised there at the school. The endangered butterflies have begun an arduous journey and will travel as much as 25 miles a day to reach their end destination, Mexico, ahead of any frost.

The butterflies were tagged with small stickers on their wings, containing a number that identifies their birthplace as Gayton Elementary School in Henrico County, Virginia. The school said that “the stickers enable the students to help provide the data necessary to save and regenerate the pollinators.”

Becky Lucas and Jill Harrell, two teachers at Gayton, carefully removed the adult insects from their net-covered nursery in which they grew and helped to set them free in front of a crowd of fourth and fifth graders. The students bid farewell to the newly transformed butterflies, who just days previously had been chunky yellow, white and black striped caterpillars.

Milkweed that was planted in the school’s garden last year was found by monarchs, who then laid eggs in the plants. In the past few weeks, the iconically colored monarch caterpillars began to emerge from the cocoons and feast on the plants. Milkweed is crucial to monarch butterflies, as the caterpillars feed exclusively on the plant’s leaves.

“Loss of habitat and herbicide use has made milkweed harder to find, so schools, homeowners and institutions are trying to pick up the slack,” the school said in a Facebook post.

The school’s garden was created as a way for students to learn about the natural world, as well as provide a setting for students to engage in social and emotional learning. The project was set into action in part by Becky Lucas, and through a grant from the Henrico Education Foundation.

The school has hopes that after the monarchs spend the colder months in Mexico, they will return to continue the life cycle right there, back in the Gayton gardens.