Tiger Swallowtail

Papilio glaucus

Papilio glaucus, commonly known as the Eastern Tiger Swallowtail, is a striking butterfly native to North America. This species is easily recognizable by its distinctive yellow and black coloration, resembling the stripes of a tiger, which is where it gets its common name. The wingspan of the Eastern Tiger Swallowtail can range from 3 to 5.5 inches, making it one of the larger butterflies in its region.

The female lays eggs on host plants, often preferring trees like wild black cherry (Prunus serotina), sweet bay (Magnolia virginiana), and tulip poplar (Liriodendron tulipifera). After hatching, the caterpillars go through several molts, displaying various colors and patterns that can mimic bird droppings or even twigs to avoid predation.

Their flight is graceful and swift, with adults frequently seen nectaring in gardens and and gliding around in the canopies of deciduous forests. This species overwinters in its pupal phase, so it is often one of the first large butterflies seen in early spring. Here in Kansas, the are usually two to three generations of this swallowtail depending on environmental conditions and host plant quality.

Fun Facts

Color Variations: While the Eastern Tiger Swallowtail is primarily yellow and black, there are also melanic forms that appear mostly black with blue, particularly in regions where predation pressure is high.

Mimicry: The melanic form mimics the appearance of the Pipevine Swallowtail (Battus philenor), the most toxic butterfly in the United States, to gain protection from predators.

Caterpillar Defense: Young caterpillars look very different from the older catepillars, being white and brown, mimicking bird guano (poop). Later instars are green to blend in with foliage and have small false eyespots to trick predators. In addition, caterpillars have retractable fleshy horn-like structures called osmeterium that protrude and release a stinky smell when the caterpillar is disturbed.