Bugging the Northwest: Moth magic with giant size and flying eyeballs

Not all moths are drab-colored pests that eat holes in clothes.

With large, velvety wings, wispy antennae and ornate patterns, the giant silk moth is the largest moth in North America and every bit as beautiful as its butterfly cousins. The problem is, they are seldom seen. Unlike butterflies, the 4- to 6-inch moths are active at night, like other moths.

Ron Allmand, who lives near Kelso, Washington, recently discovered one of these prized specimens near his home. Drawn into the darkness of early morning, he found the moth perched on an outdoor ultraviolet light. Retrieving his camera, he photographed it resting on the palm of his hand.

Because several species of giant silk moths reside in Washington, I forwarded the photograph to entomologist Michael Bush of the Washington State Department of Agriculture in Yakima to pinpoint the moth type.

It’s Antheraea polyphemus, he said, “quite possibly the largest moth that’s native to the Pacific Northwest.”

As you can see from the photograph, “it’s a beauty,” he added. It’s also a male, which tend to be smaller than the females.

But what the males lack in overall body size, they make up for with their plumy antennae used to detect pheromones emitted by the females from as far as a mile away, Bush said.

“The male moths sport these large feathery antennae that makes it easier to catch the ‘scent of a woman,’” he explained.

Whether male or female, polyphemus moths are large and butterfly-like. They also have two large fake eyes located on their hind wings that scare off predators ranging from woodpeckers to squirrels and skunks.

Speaking of those distinctive eyes, the polyphemus moth gets its name from the cyclops in Homer’s epic tale the “Odyssey.” Unlike the mythological Polyphemus giant that devours humans, this moth has no mouth parts when it becomes an adult and so doesn’t eat. Its only mission is to mate.

Because so many moths flit about outdoors as we sleep, we tend to be oblivious to their remarkable diversity. There are more than 160,000 moth species worldwide in an array colors, shapes and sizes, compared to 17,500 butterfly species, according to the Smithsonian Institute. Some moths are as small as a pinhead, others, such as the female polyphemus, are as large as an adult hand.

Of the tens of thousands of moth species, only a tiny percentage eat certain fibers in clothes, according to the book “Moths: A Complete Guide to Biology and Behavior.” What’s more, it’s the tiny caterpillars that do the munching, not the adult moths. Good news – polyphemus caterpillars do not eat clothing, preferring the foliage of birch, elm, oak and willow trees instead.