Story and Photographs By Joan Herrmann
Whereiwander… this time of year, it is generally, to wetland areas. So much is happening in and around ponds, bogs, marshes, and fens. The migratory birds have returned and will begin mating and nesting, the amphibians and reptiles have emerged from their winter habitat and will also be mating. The frogs and toads are once again singing both day and nighttime choruses. Many local nature centers have boardwalks, through their wetlands, which permit visitor inspection of the newly emerged flora (plants) and fauna (animals); without actually invading their environment.
Recently, while photographing at the pond near our property, I found the cocoon of a giant silk moth. The cocoon was attached to a small twig and was camouflaged by a few dried leaves. I carefully removed the twig which held the cocoon and brought it into our house. I knew that it would probably be emerging within a few days. By the size of the cocoon, I was sure that it was one of the three extremely large moths that can be found in our area. The Luna moth (Actias luna) is a beautiful pale green-colored moth with long hindwings and a wingspan of four to six inches. The Polyphemus moth (Antheraea polyphemus) has rusty to brown colored wings that may be six inches in width. There are large eyespots on both the fore wings and the hind wings that are ringed with yellow, black, and blue. The name Polyphemus refers to the one-eyed giant son of Poseidon in Greek mythology. The moth that eclosed from the cocoon which I found was a Cecropia moth (Hyalophora Cecropia) with a wingspan of six inches. Unfortunately, I didn’t have the privilege of seeing the actual Cecropia eclosion. Eclosion is the process that occurs when the adult comes out of the cocoon/pupal case. This is similar to watching a butterfly eclosion from its chrysalis. It is an unforgettable sight to witness the insect as it comes out of its small confinement and watch as its blood is pumped into the “rumbled wings”.
An unusual similarity that all three of these giant silk moths have in common is that their life span is very short. They have only tiny mouthparts and no digestive tracts. All eating was done as a larva and the adult part of their life is strictly for reproduction. The last few weeks of May and first few weeks of June are the time of year that this may be observed. They are nocturnal, as are most moths, and can be seen flying at night in search of a mate. The males may fly as many as twenty miles and will mate with several females. The Cecropia is a beautiful moth to observe close up. It has a rusty orange and white striped abdomen and the side of its abdomen is intersected with white circles ringed with black and black center dot. Each of its six furry legs are a rusty orange color. Its thorax appears to have a beautiful orange mane and the fore wings and hind wings have hairy scales. As you look at the tips of the fore wings you may see a profile image of a snakehead which may serve as a protection from predators.
All three of these moths share several characteristics in addition to their large wingspan; they all have heavy bodies covered in hair-like scales and reduced mouthparts. You can identify the males of these three species by their antennae. The males will have large, wide feathery antennae which allow them to find females from the pheromone that they emit. The pheromone is like an insect perfume. The female’s antennae are considerably smaller. The pheromone produced by a Cecropia female moth is significantly stronger than the other silk moth females and a study found that one-millionth of a gram of the pheromone released by a female moth, in theory, would attract one billion male moths.
Moths like butterflies all have a host plant for their eggs. That means that once the eggs have hatched the tiny larvae will begin to consume the leaves or needles of the trees where it eclosed. The host trees for the Cecropia moth are Maple trees but they also favor Tamaracks and Spruce trees. The Polyphemus larvae eat Birch, Willow, Maple, and Oak leaves and the Luna favors Paper Birch leaves.
After mating the female silk moth will lay as many as two hundred eggs on its host tree. The larvae will then feed on the leaves. The larvae will go through at least four instars as it eats and grows. An instar is the shedding of its larval skin or molting. It is similar to our children growing and needing new shoes and larger-sized clothing. Its life as a larva is one of continuous eating and growing. Its bodyweight increases by a factor of more than ten thousand. When they have reached their last instar they can be two to four-plus inches in length and as big around as an adult’s pinky finger. At the end of the summer, each silk moth caterpillar spins a cocoon to protect itself in this next to last stage of life. They are called silk moths because they will spin a fine silk that becomes their cocoon. The cocoon may be three inches in length.
Most moths differ from butterflies in that they are nocturnal (most active at night), however, there are exceptions to most rules, and there are several moths that actually are most active during the day (diurnal). One of these diurnal moths is a Clearwing. The Hummingbird Clearwing (Hemaris thysbe) is among my favorites. The Hummingbird Clearwing gets its common name from its habit of hovering when retrieving nectar from flowers, similar to the way Hummingbirds do. This moth has a proboscis (straw-like mouth part) and clubbed antenna. The Hummingbird Clearwing is colored olive green and burgundy on the body and its wings are transparent with a deep reddish-brown border. The wings originally have scales, but on its first flight some of the scales drop off leaving a “glassy” area on each wing.
Springtime is an amazing time of year to explore and observe… I hope to see you on a boardwalk soon where you wander.
As a Professional Nature Photographer, Naturalist, and Outdoor Educator, Joan Herrmann has been teaching and doing programs for Schools, Garden Clubs, Libraries, and Nature Centers, about 38 years. After moving from the Rochester area in 1995 she began her Photography business, Essence of Nature, and also became a co-owner of The Artworks in Old Forge, New York. As a docent at Munson, Williams, Proctor Arts Institute, in Utica, New York she has been educating children and adults, for nineteen years.
In 2007 she began working with the Black River Outdoor Educational Program (BROEP) and in 2013 and 2014 did a week-long summer program at BROEP in conjunction with Mohawk Valley Community College (MVCC). Using her love of both nature and photography she created a Flora/Fauna outdoor educational program teaching students (ages 6 to 14) the joys of nature and creative photography skills.
Joan’s love of nature has been a lifelong study of Birds, Wildflowers, Mosses, Ferns, Trees, Amphibians, Reptiles, Grasses, Insects, Spiders, Tracks, Scat, and Galls. She has assisted in the cataloging of all trails used by the hiking Coaches and photographed and identified seasonal Flora.
Since October 2016 she has been writing a bimonthly nature column with Adirondack Express Newspaper. In October of 2019, she began a bi-monthly column with My Little Falls Newspaper. You may reach her at email@example.com