Giant Swallowtail foraging
Channel: Leanne Grieves
Date: 2020-09-04

Giant swallowtail (Papilio cresphontes) feeding on knapweed (Centaurea sp.), an introduced flower species from Europe. Knapweeds have naturalized in Ontario, meaning they have become established and now survive and reproduce on their own. They also happen to be an excellent pollinator plant, meaning many pollinator species feed on them. Giant swallowtails are the largest butterfly in North America! The adult butterflies lay their eggs on preferred host plants. In Ontario, these are native members of the citrus family (Rutaceae) including northern prickly ash (Zanthoxylum americanum Mill.) and hoptree (Ptelea trifoliata L.) - if you plant these in your yard, the butterflies are sure to come! Giant swallowtail larvae (caterpillars) look like bird droppings - a clever adaptation to protect them from being eaten by predators!