The adult Polyphemus Moths emerge from their cocoons in the late afternoon, and mating occurs the same day from late evening to early morning. The females lay eggs that evening, singly or in groups of 2 or 3 on leaves of the host plant. The newly-hatched larvae eat their eggshells, and larvae of all ages are solitary. The older larvae eat an entire leaf and then cut the leaf petiole at the base so it falls to the ground, perhaps a defensive measure to eliminate signs of feeding (Schmidt and Robinson no date).
The Polyphemus Moth overwinters as a pupa in a large, silken cocoon. Although the oval-shaped cocoons usually fall to the ground with the host plant leaves they are wrapped in, they can occasionally be found in the winter still attached to the host plant by a small amount of silk thread. These moths typically rest suspended from a branch or twig during the day, with their wings folded above their back. The undersides of the wings are surprisingly cryptic for such a large moth. If these moths are disturbed when at rest, they often drop to the ground, and flap their wings once giving the appearance of a sudden "jump". With the eyespots exposed, this makes an impressive display which may startle potential predators (Opler et al. 2010).
There is one flight in the north from May-July, two flights in the Ohio Valley and southward from April-May and from July-August, two flights in the California Sierra Nevada, and several flights throughout most of the year in Florida, Texas, and Louisiana (Schmidt and Robinson no date).
Deciduous hardwood forests, urban areas, orchards, and wetlands (Opler et al. 2010).
The larvae feed on a wide variety of trees and shrubs including oak (Quercus)
, willow (Salix)
, maple (Acer)
, birch (Betula)
. The adults do not feed (Schmidt and Robinson no date).