20 August 2024

You may remember in early August when I wrote that two friends had black swallowtail caterpillars (Papilio polyxenes) in their gardens. By now those caterpillars are, or will soon become, butterflies.

After Betty Rowland discovered her caterpillars on 1 August her neighbor, Aaron Johnson, loaned her a butterfly tent.

Soon thereafter, on 4 August, one caterpillar posed in the pre-chrysalis position and the other had already become one.

Last Sunday I heard from Betty that after two weeks both black swallowtail butterflies had eclosed (emerged from chrysalis).

Both are female (photo at top) which is easy to see from their coloration. Female black swallowtails have orange and blue highlights; males have yellow highlights with only a hint of orange and blue (male pictured below).

After their wings dried, Aaron and his wife Erica came over to help the butterflies leave the tent. Aaron carefully flipped the tent to let them out.

Ta dah! Two black swallowtails have completed the cycle.

For a quick refresher on butterfly life cycles, here’s the monarch story from the American Museum of Natural History in New York. Black swallowtails follow the same pattern.

(Thanks to Betty Rowland for the photos and story.)