Crawling towards Fall

Look what our neighbor, Rex, found in his shed. It's the caterpillar of the cecropia moth (Hyalophora cecropia.)
With a wingspan of 5 to 6 inches, the cecropia moth is the largest North American moth. Although common enough, you don't often see them because they fly only at night. (I hope they don't run into our homeless bats!)

This crawly guy's life started last May or June, when one of over 100 eggs layed by the female moth on the underside of a leaf, hatched.

The newly hatched caterpillars, or larvae, are black and the size of a mosquito. Cecropia larva have many enemies. A newly hatched caterpillar can be the victim of even a tiny spider. Unlike some other moths, cecropias have so many enemies they never become a pest.

Before the caterpillar is ready to spin a cocoon, it will molt several times. The stages of a caterpillar's life between molts are referred to as instars. The cecropia caterpillar's colors change from its original black coloration to a green-orange color as we saw today. Those yellow and orange balls on the black spines are called tubercles.

The cecropia caterpillars feed mainly on cherry, plum, apple, elderberry, box elder, maple, birch and willow, but will also feed on linden, elm, sassafras and lilac.

Very soon he'll spend several days spinning a tough, brown, weather-resistant home. Inside the cocoon the caterpillar will pupate and prepare itself for winter and the miraculous metamorphosis in the coming spring. In their cocoons, they can survive temperatures less than thirty degrees below zero Fahrenheit! It remains protected, waiting for a beautiful spring day.

The cecropia moths emerge in late May or early June. Late at night, the female emits a scent called a pheromone that will attract a male moth. The male senses the pheromone with his sensitive antennae. He is so attracted to the scent, he can find a female from a distance of a mile away! (The attraction is very similar to a member of Congress and the scent of lobbyist's money.) The mated pair will remain together throughout the following day.

Cecropia moths do not live long (about two weeks) because the adult cecropia cannot eat. In fact, they don't even have a mouth! The only purpose of the adult stage is to mate and lay eggs.