Polyphemus Moth – Antheraea polyphemus

Polyphemus Moths are common here in west-central Wisconsin, but for a long time I had never seen any.  A few years ago some friends found a large Polyphemus moth caterpillar on our land.   After a few days it made a cocoon.  I kept it over the winter, and in the spring, when it hatched, it turned out to be a female.

I mated her and kept some of the eggs, and I've been raising and releasing them ever since.

Here are some eggs that one female, who escaped from her cage, laid all over the walls of our porch.  The dark brown patch is the "glue" that cements them to the surface.


Here are some of the eggs I pried off of the walls.


Polyphemus caterpillars can eat the leaves of many different trees and shrubs.  The lists I've seen include: Ash, Birch, Grapes, Hickory, Maple, Oak, Pine, and Cherry.  Like other Giant Silk Moths, once they start eating one kind of leaf, they don't like to switch.  I feed mine on oak leaves.  For a while I stuck to oaks in the "black oak" group - Black and Red Oak, but I've also fed them White and Burr Oak and they don't seem to care.

Here are some eggs hatching


Some first instar caterpillars on oak leaves


A later instar, just after shedding its skin


These are late instar caterpillars



They make their cocoons wrapped up in leaves - usually leaves that have fallen on the ground - or on the floor of their cage.


They spend the winter as cocoons, and sometime in May, the adults emerge.

This is a cocoon after the moth has emerged.


An adult female, soon after emergence


The moths usually emerge during the day, and by evening they're ready to mate.  The males get impatient to fly at dusk - I hear them flapping against the walls of the cage - and I release them.  The females sit still, usually at the top edge of the cage.  Males usually start showing up at midnight or 1 am.

Here's a mating pair


In this case, two males mated with one female - I don't know how they managed it, but they stayed together for a long time.


The couples usually stay together until dusk of the following day.   By dark they're both ready to fly - flapping against the cage.

Here's a female in a cherry tree.  I had released her the night before, but she was still there the next day.



Buffalo County, Wisconsin

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