Adult Pipevine Swallowtails are poisonous to predators, so most birds avoid them. Several butterfly species have developed mimicry to copy it's appearance and gain 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.