Field Notes

Dive into the world of butterflies found in Vermont

15 min read / August 6, 2025 / By Sarah Wolfe

Look a little closer at butterflies

Butterflies are a welcome sight all summer long. So if you’d like to take a closer look at these winged wonders, read on. We’ve partnered with the Vermont Center for Ecostudies (VCE) and their Second Vermont Butterfly Atlas to share some tricks for identifying species you can find right here in Vermont. Thanks to their expertise, you can start to recognize species in your backyard, and learn about how to help them thrive.

Butterflies you might see in Vermont

How to talk about butterflies

The lookalikes: monarch vs. viceroy

The cosmopolitan: painted lady

The show-off: tiger swallowtail

The grammar crew: commas and question marks

The bad rap: cabbage white

The carnivore: Harvester

The butterfly food chain starts with native plants

Help uncover the mysteries of Vermont’s butterfly population

All photography was shot in Vermont by Patrick LaClair, except where noted.

Butterflies you might see in Vermont

Around 120 species of butterflies can be found in Vermont during the summer months. That might seem like a lot, but it’s a fraction of the estimated 20,000 butterfly species known worldwide.

Scientists group butterflies into six families, five of which exist in Vermont.

Brush-footed butterflies

There are 39 species found in Vermont.
Typically medium to large butterflies with bright, often orange, coloring.
Named for their smaller front feet that in some species are covered in brush-like hairs.

Photo: A red admiral butterfly on ninebark.

Swallowtails

There are seven species found in Vermont.
Large, typically yellow and black with some blue markings.
Some species have a forked appearance in their hind wings, similar to swallows, giving rise to their name.

Photo: A spicebush swallowtail.

Whites & Sulphurs

There are eight species of whites and sulphur found in Vermont.
They display white or yellow coloring.

Photo: A clouded sulphur butterfly resting on the ground.

Gossamer-winged butterflies

There are around 26 species found in Vermont.
They tend to be small, grey or blue, and delicate-looking.

Photo: Gray hairstreak butterfly, taken by Amber Jones. CC BY 4.0. Cropped from original.

Skippers

There are 37 species found in Vermont.
They tend to be small and fast-flying.
They have orange, black, brown, and gray coloring.

Photo: A silver-spotted skipper on bee balm. Note the hooked antennae, a trait shared by many skippers.

Metalmarks

The only family of butterflies not found naturally in Vermont.
Found primarily in Central and South America, though this Rounded Metalmark was spotted in Austin, Texas.

Photo taken by Al Johnson. CC BY 4.0. Cropped from original.

How to talk about butterflies

Here’s a guide to a few useful terms we use to identify butterflies.

Caterpillar: Caterpillars are the larval, or immature, form of butterflies. Most caterpillars hatch within 4-14 days. After hatching, caterpillars eat voraciously for two to four weeks. Some species grow up to 100 times their size between hatching and pupation!

Photo: A red admiral caterpillar resting on a leaf.

Chrysalis: A chrysalis is the pupal, or transitional stage, between caterpillar and butterfly. Caterpillars develop a hardened skin, which forms the exterior of the chrysalis. Inside the chrysalis, the caterpillar transforms into a butterfly. Chrysalises hang by a spun silk thread from a twig or leaf for ten days to several weeks.

Photo: The chrysalis of a question mark butterfly. Taken by Kate Taylor. CC BY 4.0. Cropped from original.

Cocoon: A cocoon is a spun silk enclosure used by moths during the pupa stage. Butterfly larva only spins silk to hang from in its chrysalis. Moth larva spins a full protective covering, and often incorporate plant material like leaves. Moths remain inside the cocoon until they emerge as an adult moth.

Photo: A broken-banded leafroller moth in its cocoon. Taken by joannerusso. CC BY 4.0. Cropped from original.

Migration or overwintering: Vermont’s butterflies have several strategies for surviving the cold. Some, like monarchs, painted ladies, and red admirals, migrate south for the winter. Some hibernate as adults, finding shelter in tree hollows, leaves, or buildings. Some species overwinter as eggs, which are generally too small to freeze. Some caterpillars burrow into a warm, protected spot for the winter months. Finally, some butterfly species overwinter as chrysalises. These butterflies stay dormant until spring comes, when they emerge as adults.

Photo: A monarch butterfly.

Terms used for visually identifying butterflies

Upper side (Dorsal): The top of the butterflies wings, looking from above when open.

Underside (Ventral): The bottom of the butterflies wings, looking from below when open or from the side when closed.

Fore wing: Butterflies have two sets of wings on each side. The fore wing is closer to the head.

Hind wing: The hind wing is closer to the tail.

Photo: A comma butterfly showing off its ventral side.

Monarch vs. Viceroy: The Lookalikes

Some butterfly species evolve to look alike. There are many reasons they may do this. In the case of the monarch and the viceroy, it’s mutually beneficial. Both are foul-tasting to their predators. After an initial attempt to eat one, a potential predator might steer clear of both species.

Photo: A close-up view of a monarch’s wing.

The adult butterflies’ appearance might fool you, too. But there are a few key differences between these mimics:

Size: Monarch butterflies are one of the largest species in Vermont. Their wingspan can be up to five inches. Viceroy butterflies’ wingspan gets up to a little over three inches.

Black stripe: Look at the smaller hind wing. Viceroy butterflies have a black stripe going acrossthe vertical veins. The monarch’s veins are uninterrupted.

Photo: Top, a monarch butterfly. Bottom, a viceroy butterfly, taken by Jack Forrester. CC BY 4.0. Cropped from original.

Caterpillar: The mimicry only begins in the adult phase. The caterpillars are quite distinct. Monarch caterpillars have yellow, white, and black stripes. They exclusively eat milkweed. Viceroy caterpillars are a mottled brown and white that resembles bird droppings. They eat willow and poplar leaves.

Photo: Top, a monarch caterpillar, taken by saylorj. Bottom, a viceroy caterpillar, taken by shcrifield. Both CC BY 4.0. Cropped from originals.

Migration: Monarchs are famous for their annual migration. They travel en masse from the Northeast to Mexico for the winter. Usually, a single generation makes the entire flight south in the fall – they generally do not breed during the journey. Coming back north, it takes multiple generations to reach the northern United States and Canada each summer. Viceroys overwinter in Vermont in their larval or caterpillar form. They roll up in the leaves of their host plant (willow or poplar) and go dormant. When the air warms in the spring, they form a chrysalis.

Photo: A Monarch butterfly resting on an orange flower.

Painted Lady: The Cosmopolitan

Painted lady butterflies, like monarchs and viceroys, come from the Brush-footed butterfly family. They have similar orange and black coloring, but they have eyespots and more brown on their wings. They’re also smaller, with a wingspan of about two inches. Like monarchs, they migrate, but their migrations are less predictable and they tend to fly higher. That makes their migration harder to observe.

Photo: An upper side, or dorsal, view of a painted lady, taken by jme314. CC BY 4.0. Cropped from original.

Painted ladies are uniquely adaptable and widespread. They will lay eggs (and feed, as caterpillars) on a wide variety of host plants. They also breed throughout their migration. That means new caterpillars hatch along the migration routes. That’s helped them thrive on every continent except Antarctica and Australia. (Did you ever have caterpillars in your classroom in school? They were probably painted ladies. Their adaptability makes them easy to raise and study.)

Photo: A painted lady caterpillar resting on a leaf. Taken by emilyk04. CC BY 4.0. Cropped and rotated from original.

Tiger Swallowtail: The Show-Off

The tiger swallowtail’s bright yellow and black stripes make it one of Vermont’s most recognizable butterflies. (There are three species of tiger swallowtail in Vermont, but they’re hard to distinguish.) Look closer and you’ll see the tiger’s iridescent blue spots decorating the tail of its hind wing, contrasting with the yellow and black. With a wingspan of up to 5 ½ inches, it’s also one of the largest butterflies in Vermont.

Photo: The Canadian tiger swallowtail shows off its surprising blue color. There are three species of tiger swallowtail found in Vermont: the Canadian tiger swallowtail, the Eastern tiger swallowtail, and the Midsummer tiger swallowtail. The three are difficult, but not impossible, to distinguish.

The soft green caterpillars are easy to pick out. Look for yellow and black eyespots along their backs, designed to scare predators.

Photo: A Canadian tiger swallowtail caterpillar. Taken by amandammvt. CC BY 4.0. Cropped and rotated from original.

Commas and Question Marks: The Grammar Crew

Viewed from above, the comma and the question mark butterflies look almost identical. Black spots decorate the upper (or dorsal) side of the orange-brown fore wings. Orange fades to darker brown with light spots at the edges.

Photo: A question mark butterfly shows off its upper (or dorsal) side.

The dark, mottled underside (or ventral side) gives these butterflies the appearance of dried leaves when their wings are folded. They use this disguise to hide from potential predators.

Tell them apart by looking for a small silvery mark on the underside of their wings. For the comma, it’s a small arc, and for the question mark, there’s an added dot.

Photo: On the left, a question mark butterfly, and on the right, a comma butterfly. Some say the question mark symbol looks more like a semicolon or fermata.

You’ll rarely see either at a flower, as they choose to feed on rotting fruit, tree sap, or dung. Their multi-colored caterpillars stand out with branching spines. They aren’t too picky either, feeding on plants including nettles, elms, willows, and more.

Photo: A question mark caterpillar. Taken by Bruce Cook. CC BY 4.0. Cropped from original.

Cabbage White: The Bad Rap

The innocuous-looking cabbage white butterfly caterpillar is the foe of vegetable gardeners all summer long. The bright green caterpillar blends in with leaves. That makes it hard to find as it munches hungrily on the leaves of cruciferous plants (kale, cabbage, brussels sprouts, and their relatives). They can decimate a garden crop, even boring into the center of the plant to feed on new sprouts.

Photo: A cabbage white caterpillar on a leaf, with evidence of its appetite. Taken by Darien Harris. CC BY 4.0. Cropped from original.

The adult butterflies appear yellow on the underside of their wings. Black-brown spots and shading adorn the upper side of their wings. The wingspan ranges from one to two inches. Though a highly competitive introduced species, the adult butterfly is still an important pollinator. If possible, encourage the adults to lay eggs outside of your garden using one of these strategies:

Netting around cruciferous plants
Planting nasturtiums alongside or nearby as ‘companions.’ Nasturtiums are also host plants for the cabbage white.

Photo: A cabbage white butterfly just above a cabbage plant.

Harvester: The Carnivore

If you have sharp eyes, you may be lucky enough to spot a unique butterfly this summer. The harvester is North America’s only carnivorous butterfly species. The caterpillar feeds exclusively on aphids. Even the adults will forgo flowers to drink honeydew (the substance secreted by aphids after feeding on plant sap).

Photo: A harvester caterpillar in Maine. Taken by Elise Smorsczewski. CC BY 4.0. Cropped from original.

The harvester’s wings grow to just over an inch, with an orange-brown background and black spots on the upper side. The underside has small, faint white circles. The carnivorous caterpillar is fuzzy with white and orange-brown stripes and small black spots.

Photo: The underside of a harvester butterfly. Taken by Bernie Paquette. CC BY 4.0. Cropped from original.

The butterfly food chain starts with native plants

For butterflies to reach adulthood, they first have to survive being a caterpillar. Most butterfly species will only lay eggs on a specific plant, called a host plant. The hatching caterpillar eats this plant’s leaves. Caterpillars have to eat almost constantly until they form their chrysalises. Many caterpillar species can only eat their specific host plant. Butterfly species have often co-evolved with a plant species. Eating other plants can be toxic to caterpillars. When these native host plants aren’t available, caterpillars may not survive to adulthood.

Declining native plants and fewer caterpillars have impacts beyond butterflies. If you have a yard or access to a garden plot, consider planting native plants to help butterfly populations (and other native pollinators) thrive. You can also try to control the spread of introduced species.

link

5 plants to watch for this fall (and why we aren’t calling them invasives)

Help uncover the mysteries of Vermont’s butterfly population

For years, butterflies were a mystery in Vermont. Beautiful, and appreciated, but largely unstudied. In 2002, the Vermont Center for Ecostudies (VCE) launched the first Vermont Butterfly Atlas. Volunteer scientists documented the number and locations of butterflies across Vermont.

Twenty years later, VCE is updating that landmark effort. The second Vermont Butterfly Atlas will capture how Vermont’s butterfly populations have changed. VCE hopes to understand whether conservation efforts can help protect vulnerable species. We are teaming up with VCE to encourage participation in the second Vermont Butterfly Atlas.

Photo: A close-up of the Canadian tiger swallowtail’s hind wings.

Ready to help Vermont understand its butterfly population better?

We recently hosted a webinar with VCE to help participants get started. Watch the recording or find another upcoming event to join the crew of butterfly identifiers working across the state.

Join the Atlas