These are Black Swallowtails. The Black Swallowtail, one of North America’s most common butterflies, frequently visits backyard gardens. Nicknamed parsley worms, the caterpillars feed on parsley, dill, fennel, and other members of the carrot family.
This large butterfly has black wings with yellow markings and a wingspan of 8-11 cm. The male displays a row of bold yellow spots, while the female’s spots are faded shades of yellow and blue.
