I’m out to enjoy a glorious July evening, baked in the glow of the sinking sun, with background music by Indigo Buntings, Northern Parulas, Song Sparrows, and Red-eyed Vireos. A Monarch butterfly flitters through a low shaft of light, its wings a translucent flaming orange; its flight a moment of aerial dance. A moment that evokes delicate beauty, fragile life, and the rhythms of Earth’s only biosphere.
They don’t sting you. They don’t bite you. They don’t buzz around your sweating head. They don’t damage your trees. They don’t eat your precious woolens, your garden vegetables, or the timbers in your house. They don’t breed or fester in your ponds and puddles. They present themselves with elegant beauty and ephemeral dignity. Butterflies are the finest ambassadors among all arthropods. They fly about in the warm days of spring, summer, and autumn, flashing their vibrant colors then moving along.
A visit to the Fairbanks Museum’s Butterfly House invites you to a close-up encounter with butterflies, the plants their caterpillars prefer to munch on, and the flowers that feed them sweet nectar. Established by the Museum’s Leila Nordmann, the Butterfly House has become a highly popular site for live nature adventures for all ages. Bright, sunny, screened, warm, and breezy, the Butterfly House invites close observation of these fascinating insects. In mid-summer, Leila and her assistants will introduce you to common Painted Ladies and the famous Monarch butterflies. On warm spring or early summer days, you may meet Tiger Swallowtails or Black Swallowtails and the occasional stunningly large Cecropia Moth.
Butterflies and moths belong to a huge order of 180,000 species around the planet, the Lepidoptera (“scaly wings”). From a shared ancestor hundreds of millions of years ago, butterflies and moths have evolved along different paths. Most butterflies are active in daylight, most moths are nocturnal. This affects their appearance and behavior; diurnal butterflies display bright colors in their wings and bodies to attract mates and warn off predators; nocturnal moths may display less flashy yet complex and cryptic patterns that camouflage them during the resting day and may deceive potential predators.
The butterfly’s life passes through the stages of “complete metamorphosis,” beginning as a tiny egg deposited by a female on a leaf of a food plant preferred by that species, for example, Monarch butterflies and Milkweed leaves. Soon emerging from the egg, a ravenous caterpillar will feed on that host plant and will grow rapidly, molting several times. In this feeding stage, the caterpillar accumulates the vital proteins and other nutrients necessary to sustain the rest of its life. When preparing for adulthood, the caterpillar becomes a dormant pupa encased in a delicate chitinous shell (chrysalis) for a few weeks or, in some species, for the winter months. Finally, the chrysalis splits and a new adult slowly emerges with wings, antennae, six limbs, and three body sections: head, thorax, and abdomen. These adults lack chewing parts in their mouths, but they uncoil a proboscis that works like a drinking straw, sucking up flower nectar, sap, water, and essential dissolved minerals. In the brief adult stage averaging only about two weeks, the task of all butterflies is reproduction. Some are known to pollinate flowering plants as they suck up the sweet nectar that sustains them.
When on duty in the Butterfly House, Leila shares stories of many of the distinctive features of butterflies. Like other insects, butterflies sport compound eyes, comprised of many hexagonal lenses. Their visual capacity spans a much broader spectrum than ours, and their capacity to see polarized light enables them to navigate their mobility, on breeding grounds and, for Monarchs, in seasonal migration. Their two antennae help them to sense scents and to feel the movement of the air.
Among their most vital senses butterflies have for exploring their world, one is my favorite. As described by Leila, butterfly feet, or tarsi, are highly sensitive to the chemicals they touch. This helps them to identify food plants for their eggs and larvae. But as Leila puts it, “If your feet were like a butterfly’s, they’d be smelling stinky sneakers or tasting muddy boots.”
The fragility of butterflies is part of their charm. The life span of most butterfly adults is brief, long enough only to spawn the next brood in time for the annual life cycle for the next year. Migratory eastern Monarchs, wintering in Mexico, are unusual in that it takes several generations to make the northbound spring journey each year. Several other northern species will take short journeys a few hundred miles southward in the fall to avoid the most severe temperatures of our northern climate.
Observing wild butterflies is intensely relaxing! A brief aerial dance will challenge you to follow one butterfly’s behavior and journey. Good luck. In summer, you are likely to notice a scrum of butterflies on a patch of damp sand or the edge of a puddle. Gathering minerals, swallowtails display this behavior in June, but the big show is the hundreds, or thousands, of tiny orange European Skippers you may encounter in a gravel driveway on a sunny day in July or August. As quickly as they convene, they disperse within a few days. This “Puddling”, as well as “Hilltopping” on a steep, sunny, open hill, is comprised mostly of males obtaining the nutrients they’ll need to breed. Females are less conspicuous, breeding in locations near their host plants where they deposit their eggs. Compared to birds, butterfly territoriality is brief and modest.
Some 115 butterfly species are found in New England, each with its own distinctive size and color, its preferred food and nectaring plants, its flight behaviors and resting postures, and its rhythms and cycles within the seasonal schedule of the region. But pay attention to butterflies; these ambassadors could teach much to our own species!
With special thanks to Leila Nordmann and the handbook Butterflies of New England by Larry Weber.
Charlie Browne is a naturalist, educator and the director emeritus of the Fairbanks Museum & Planetarium. He has been a popular lecturer on birds and bird behavior and served for several years as guest naturalist on WCAX-TV News. He and his wife, Wynne, live on East Hill in Peacham.