Summer is when many people are aware of insects, both annoying ones and beautiful examples. Butterflies and moths are some of the more noticeable insects, given their relatively large size and sometimes lovely colors. Yet most people do little more than casually acknowledge these gentle fliers.

Moths and butterflies are in the insect order Lepidoptera which in Greek means scale (lepis) wings (pteron). Their delicate wings and bodies are covered with tiny scales, which are modified hairs that shed throughout the insects’ adulthood. The color and pattern of the scales provide identification clues. But butterflies aren’t always the colorful ones. The plain white cabbage “moth”, commonly seen in gardens, is actually a butterfly. By contrast, species such as the cecropia, luna and primrose moths are strikingly beautiful.

Another myth often used to distinguish butterflies from moths is that the former flies in the daytime and the latter is nocturnal. This is true for most species, but not all. Hummingbird moths flit about on summer days. They are so large they resemble their namesake as they hover around flowers in search of nectar. A few butterflies are crepuscular (active at dawn and dusk).

A more reliable distinction is found by looking at their antennae. A butterfly’s antennae are long, slender shafts with a bulb at the tip. The moth antennae are feathery or saw-edged. Moths also have a “frenulum”, a wing-coupling structure which attaches the front and back wings, enabling them to work in unison during flight. Butterflies do not have frenula.

All Lepidoptera go through a four-stage complete metamorphosis. An egg hatches into a larva which eats, grows, molts, and then pupates. A moth caterpillar will spin a silken cocoon while a butterfly caterpillar molts into a chrysalis, which is more like its exoskeleton. Within each of those protective coverings, the larva releases enzymes and dissolves into a goopy soup. A few cells survive this process, and they use the protein-rich soup to fuel the growth of adult body parts. When the transformation is complete, the moth or butterfly emerges, unfolding scale-covered wings. Before it can take flight, it must pump fluid into its wings and let them dry. Once the wings are fully developed, most of these transformed insects begin an entirely new life stage as a flying adult. In some species of moths, the females do not fly.

The miraculous life cycle is something that butterflies and moths have in common, but the stages may happen at different seasons and take various lengths of time. Some species such as the non-native spongy moth (formerly called gypsy moth) spend most of their life in the egg form. During a few weeks in late spring through mid-summer the larvae munch on leaves, pupate and emerge as adults. From now through May their presence is known only by fuzzy tan egg masses attached to tree bark.

The most common stage for insect overwintering is the larva. Isabella moth larvae, commonly called wooly bear caterpillars, curl up under loose bark or in a protected spot. Larvae of the viceroy butterfly (a near look-a-like to the monarch) spend the winter in a rolled-up leaf. The great-spangled fritillary caterpillar buries in leaf litter or soil at the base of violets (their primary food source).

Many species spend the dormant season in a pupa stage. Local examples include the eastern (or Canadian) tiger swallowtail and black swallowtail butterflies and cecropia moths.

Monarch butterflies are known for their amazing migration, surviving the winter by escaping to Mexico. There are a few butterflies, such as mourning cloaks, that survive northern winters as adults, hidden in bark crevices, emerging in the first warm days of spring.

Thankfully, winter is still months away, so take time now to look for adults, larvae, pupae and even eggs of some of these moths and butterflies. Observations can help us learn more about these insects. This year, the NH Fish and Game Department launched The Butterfly Monitoring Network, a citizen science project that trained residents to gather data about local butterflies to help with their conservation. The study period is over for this year, but it’s never too late to learn about our wild neighbors. If you are interested in becoming involved in data collection, there may be another opportunity next year. To learn more visit: wildlife.state.nh.us/surveys/butterfly-monitoring-survey.html

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