Moths are everywhere, including your own backyard. In fact, more than 11,000 species of moths have been identified in North America. An astonishing number, considering there are a “mere” 575 species of butterflies. Despite their diversity and abundance, moths have attracted less study than their more glamorous cousin, the butterfly. That leaves a lot yet to be discovered about moths – perhaps by you!
National Moth Week, July 18-26, is a great time to try “Mothing”. This easy, inexpensive hobby can be pursued right at home. With a few simple pieces of equipment, you can take an up-close look at our fascinating neighbors and share observations that build our understanding of the magnificent, mysterious moth.
Outside the polar regions, moths are found across the Earth (their abundance makes them an important pollinator of flowering plants) and in all sizes and colors. They range from the 6” long Cecropia moth to the tiny (1.2 mm) Stigmella maya. Some vibrate with color. Others are drab to better blend with their environment.
Moths are distinguished from butterflies by a stout body covered in dusty scales, and feathery, thick antennae. Look but do not touch. Touching can easily damage a moth’s wings. A resting moth extends its wings to the side or holds them tent-like over the body, unlike butterflies which hold their wings vertically.
Like butterflies, moths develop through the process of metamorphosis. An egg hatches into a tiny caterpillar (the larval stage). Eating voraciously, the caterpillar develops through several growth stages called instars. At the end of the final instar, the caterpillar either spins a cocoon or splits its outer skin to expose the chrysalis beneath. The cocoon or chrysalis protects the insect while the transformation from pupae to adult occurs. When metamorphosis is complete, the adult moth emerges and completes the life cycle by laying the next generation of eggs.
Moths can be highly destructive in their larval stage. Vegetable gardeners dread the appearance of the tomato hornworm. These large green horned caterpillars can quickly consume tomato plants. In the adult stage, the tomato hornworm transforms into the beautiful sphynx moth. Also known as “hummingbird moths” due to their size and flight pattern, sphynx moths are important pollinators of summer flowering plants.
Mothing can be done any time of day, though nighttime provides the easiest viewing. Start by simply turning on your porch light; a number of moth species are attracted by white light (LED or CFL work best). Use a black light and a sheet to attract additional species. Hang a white sheet (cotton works best to reflect the UV rays) between two trees or attach it to your fence. Be sure all four corners are secured as moths prefer a stable surface for landing. Place a black light or a plant grow light next to it and wait a few minutes for these beautiful insects to arrive. Your mothing endeavors will be off to a flying start.
You may also want to experiment with sugar bait in order to attract nectar feeding moths. Homemade sugar bait can be fashioned from ingredients on hand in your kitchen. Try blending together a ripe banana, one cup of brown sugar, two tablespoons of molasses and a half cup of flat beer or apple cider. For best results, allow the mixture to sit at room temperature for a day prior to your planned observation. Paint the mixture onto the trunk of a tree or two and wait for nectar feeding moths to land. Check with mothscount.org for more ideas on attracting moths.
For identification help, choose a good quality moth guide such as the Peterson Field Guide to Moths of Southeastern America, by Seabrooke Leckie and David Beadle (cost about $30). Small laminated moth guides are easy for children to use. Try Texas Butterflies and Moths: A Folding Pocket Guide to Familiar Species, by James Kavanaugh. This guide is often available in local groceries or may be purchased online.
Share your backyard moth observations with other citizen scientists by joining National Moth Week July 18-26. The information you submit will be used to help map moth distribution and collect other data. Join today and have fun mothing!
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