Western Tiger Swallowtail Caterpillar
Papilio rutulus (caterpillar)
This larval stage feeds on leaves of willows, cottonwoods, aspens, alders, and related trees in riparian woodlands and open western forests. Young caterpillars resemble bird droppings, while older ones turn green with large eyespots that can startle small predators. When disturbed, a forked orange osmeterium can be everted from behind the head, releasing a strong-smelling chemical defense. Most of its time is spent eating and resting along leaf surfaces before pupation.
- Type
- Venom
- Conservation status
- NE
Growth chain
- Western Tiger Swallowtail Caterpillar
- Western Tiger Swallowtail Chrysalis
- Western Tiger Swallowtail