The Pipevine Swallowtail can be a difficult butterfly to identify, because there are several other butterflies with the same size and colors. Pipevine Swallowtails can have a wingspan up to 3 1/2 inches. They are black with bluish-green metallic color on the hind wings. Females have a row of yellowish-white dots, males do not. When a Pipevine Swallowtail folds its wings while it's resting, you will see a curved row of bright orange dots underneath its wings. Pipevine Swallowtails are found in fields, meadows, gardens, parks, open woods, roadsides, and stream sides. These butterflies fly from April until early Fall.
During breeding season, the male Pipevine Swallowtail patrols a territory, waiting for a female to arrive. After mating, the female lays several eggs on the underside of a leaf. Eggs are rust-colored. Pipevine Swallowtails only lay their eggs on host plants which their larvae will be able to eat. Host plants include plants from the Pipevine Family, such as Dutchman's Pipe and Virginia Snakeroot. Larvae will not eat any other types of plants.
Butterfly larvae, called caterpillars, are small and stick together when they are first born. They eat the leaves of their host plant and grow quickly. Plants in the Pipevine Family have chemicals in them which are poisonous to most animals. Caterpillars are able to eat them without being harmed. In fact, the chemicals stay inside the caterpillars and make them poisonous to most predators. Caterpillars are not poisonous when they are young, but after they have eaten a lot of pipevine and have grown, they are poisonous and move off to live on their own.
Pipevine Swallowtails are a big help to other butterfly species without even trying. Because adult butterflies are poisonous to predators from all the pipevine they eat as caterpillars, most birds avoid them. Other butterfly species have developed mimicry. Mimicry is when one animal copies the look of another, and gains protection. Some species that mimic Pipevine Swallowtails include Eastern Tiger Swallowtail (females), Eastern Black Swallowtail, Spicebush Swallowtail, and Red-spotted Purple. None of these species are poisonous, but birds avoid them because they have the same color and size as Pipevine Swallowtails.