Types of Butterflies in Alaska
Alaska has around 80 butterfly species, a small but remarkable fauna of sulphurs, lesser fritillaries, alpines, arctics and blues built to survive nine months of winter and fly through a summer of near-continuous daylight. The showpieces are the Canadian Tiger Swallowtail and the Alaskan race of the Old World Swallowtail, the Phoebus and Eversmann's Parnassians of the mountain slopes and a dozen Colias sulphurs, more than anywhere else in North America. Alaska has no state butterfly; its state insect is the Four-spot Skimmer dragonfly.
On this page
- Butterflies found in Alaska
- Butterflies of Alaska at a glance
- Signature Alaskan butterflies
- The Alaska butterfly calendar
- Where to see butterflies in Alaska
- Host plants and butterfly gardening in Alaska
- Rare and threatened butterflies in Alaska
- How to identify butterflies in Alaska
- Frequently asked questions
Butterflies of Alaska at a glance
Alaska is the largest state and has one of the shortest butterfly lists, around 80 species, because almost everything here must survive a winter of minus 40 degrees and complete its life in a summer of ten or twelve weeks. What the fauna lacks in numbers it makes up in character: most Alaskan butterflies are Holarctic species shared with Siberia and Scandinavia, and several, such as Eversmann's Parnassian, the Arctic White and the Hecla and Booth's Sulphurs, are found nowhere else in the United States.
Five families are present. The brush-footed butterflies supply the lesser fritillaries of the genus Boloria, the hibernating tortoiseshells and commas, and the alpines and arctics, sombre brown satyrs of the tundra that the identification chart barely touches. The whites and sulphurs are the second family and the state's speciality, with a dozen Colias sulphurs. Four blues, four swallowtails and parnassians, and four skippers complete the list; there are no metalmarks and no hairstreaks.
Butterflies fly from the coastal rainforest of Southeast to the Brooks Range and the Arctic coast, but the richest ground is the dry Interior around Fairbanks and the alpine ridges of the Alaska Range and the Chugach, where sun-warmed tundra and south-facing bluffs concentrate everything that flies.
Signature Alaskan butterflies
The Canadian Tiger Swallowtail is the biggest and most conspicuous butterfly in the state. In June the yellow-and-black males gather by the dozen on damp gravel along Interior roads, and the caterpillars feed on aspen, birch and willow. The Old World Swallowtail in Alaska is the subspecies aliaska, a hilltopping butterfly of tundra ridges whose caterpillars feed on arctic wormwood rather than the carrot family used by its relatives farther south.
The two parnassians are the mountaineers of the swallowtail family. The Phoebus Parnassian, white with red spots, flies on alpine slopes where its caterpillars eat roseroot stonecrop, and Eversmann's Parnassian, the only yellow parnassian in the world, is a Siberian species that reaches North America only in Alaska, the Yukon and northern British Columbia, breeding on corydalis in the mountains of the Interior.
The sulphurs give Alaska its colour. The Clouded Sulphur and Christina's Sulphur are the common yellow butterflies of roadsides and meadows, the Palaeno, Pelidne and Giant Sulphurs fly over bog and muskeg, and the Hecla, Labrador, Canadian and Booth's Sulphurs are true tundra insects, greenish or orange, that fly low and fast over the ridges. The Mourning Cloak, Milbert's Tortoiseshell and Green Comma are the first butterflies of spring, the Silvery Blue and Northern Blue fly over lupine and blueberry, and the Arctic, Silver-bordered, Mountain and Mormon Fritillaries are the small orange butterflies of every wet meadow.
The Alaska butterfly calendar
Nothing flies before the snow goes. The first butterflies, usually in late April or early May around Fairbanks and Anchorage, are the Mourning Cloak, Milbert's Tortoiseshell and Green Comma, adults that spent the winter frozen under bark and leaf litter. Late May brings the Spring Azure, the Western White and Creamy Marblewing, and the first Old World Swallowtails on the hilltops.
June is the month for swallowtails, parnassians, blues and the Arctic Skipper, and from mid-June to late July everything else joins them: the sulphurs and lesser fritillaries in the lowlands, then the tundra species as the alpine slopes clear of snow. With the sun barely setting, butterflies feed late into the evening, and a warm July day on a Steese Highway summit can produce twenty species. Numbers fall away in August, when the last Clouded Sulphurs and Grizzled Skippers disappear.
Alaska has almost no migration. The Painted Lady arrives from the south in a few summers and breeds briefly, but nothing leaves in autumn. Instead the whole fauna winters in place, as our guide to where butterflies go in winter explains: eggs, caterpillars and pupae freeze solid, protected by glycerol and other antifreezes, and many tundra species need two summers to grow, so adults appear in numbers only every other year.
Where to see butterflies in Alaska
Roads that climb above the treeline are the best butterfly sites in Alaska, and most are within a day of Fairbanks or Anchorage.
- Eagle Summit and Twelvemile Summit, Steese Highway — the classic tundra sites north of Fairbanks for Hecla, Booth's and Labrador Sulphurs, Eversmann's Parnassian, alpines and arctics in late June and July.
- The Denali Highway — 217 km of gravel road through tundra and taiga between Paxson and Cantwell, with lesser fritillaries, sulphurs and puddling swallowtails.
- Hatcher Pass and Chugach State Park, near Anchorage — Phoebus Parnassians, Mormon Fritillaries and Northern Blues on the alpine trails.
- Thompson Pass, above Valdez — snow-fed meadows with Mountain and Arctic Fritillaries.
- The Dalton Highway and Atigun Pass — the Brooks Range and the North Slope for the hardiest arctic species.
- The University of Alaska Museum of the North, Fairbanks — the state's reference insect collection.
The same fauna continues east into the Yukon, covered on our page for butterflies in Canada, and the coastal rainforest species of Southeast Alaska are shared with Washington and British Columbia.
Host plants and butterfly gardening in Alaska
Alaskan butterflies are tied to native host plants of the boreal forest and tundra, and a garden in Anchorage or Fairbanks attracts them best by keeping those plants rather than importing southern ones.
- Aspen, birch and willow — Canadian Tiger Swallowtail, Mourning Cloak, Green Comma and Persius Duskywing.
- Stinging nettle — Milbert's Tortoiseshell.
- Lupine, vetch and other legumes — Silvery Blue, Northern Blue, Western Tailed-Blue, Clouded and Christina's Sulphurs.
- Blueberry, bog bilberry and crowberry — Palaeno, Pelidne and Northern Blue.
- Violets, willow and bistort — the lesser fritillaries.
- Roseroot stonecrop and corydalis — the Phoebus and Eversmann's Parnassians.
- Cloudberry — Grizzled Skipper.
- Wild mustards and rockcress — Arctic White, Western White and Creamy Marblewing.
For nectar, fireweed, wild geranium, yarrow, Jacob's ladder and cinquefoil draw sulphurs and fritillaries through July, and damp gravel or a wet sand patch in the sun will bring swallowtails and blues down to drink.
Rare and threatened butterflies in Alaska
No Alaskan butterfly is listed under the Endangered Species Act, and none is close to it; the state's butterflies live mostly on public land where habitat is intact. The worry is climate. Alaska is warming faster than any other state, shrubs are spreading across tundra that arctics, alpines and tundra sulphurs need open, and warmer, wetter winters can be fatal to species whose overwintering stages are adapted to a dry, deep freeze. Species at the southern edge of their range here, such as the Hecla and Booth's Sulphurs and Ross's Alpine, are the ones to watch, and the state wildlife action plan lists several tundra butterflies as species of concern for that reason.
Field surveys are thin across most of the state, so the list is still growing, and the two-year life cycle described in our guide to how long butterflies live makes Arctic species hard to count.
Butterflies found in Alaska
34 species listed for Alaska, grouped by family. Linked names have a full profile on this site with pictures of every life stage.
Brush-Footed (Nymphalidae)
Aglais milbertiMilbert’s Tortoiseshell (Aglais milberti)Milbert’s tortoiseshell (Aglais milberti) is a medium-sized brush-footed butterfly of northern North America, from Alaska and Canada south through the
Nymphalis antiopaMourning Cloak (Nymphalis antiopa)The mourning cloak (Nymphalis antiopa) is a large dark butterfly of woodland, riverbank and suburb across North America and temperate Eurasia, and not
Vanessa carduiPainted Lady (Vanessa cardui)No other butterfly lives on so much of the planet.Show all 7 other brush-footed species names
- Green Comma (Polygonia faunus)
- Arctic Fritillary (Boloria chariclea)
- Mountain Fritillary (Boloria napaea)
- Silver-Bordered Fritillary (Boloria selene)
- Mormon Fritillary (Speyeria mormonia)
- Ross's Alpine (Erebia rossii)
- Field Crescent (Phyciodes pratensis)
Gossamer-Winged (Lycaenidae)
Celastrina ladonSpring Azure (Celastrina ladon)The spring azure is often the first butterfly of the year, a small violet-blue flake that appears along a woodland edge while the trees are still bare
Glaucopsyche lygdamusSilvery Blue (Glaucopsyche lygdamus)One of the first blues on the wing each spring, the silvery blue flashes metallic silver-blue in flight and then settles to show a plain grey undersid- Northern Blue (Lycaeides idas)
- Western Tailed Blue (Cupido (Everes) amyntula)
Whites and Sulphurs (Pieridae)
Show all 11 other whites and sulphurs species names
- Arctic White (Pieris angelika)
- Western White (Pontia occidentalis)
- Creamy Marblewing (Euchloe ausonides)
- Palaeno Sulphur (Colias palaeno)
- Christina's Sulphur (Colias christina)
- Giant Sulphur (Colias gigantea)
- Pelidne Sulphur (Colias pelidne)
- Labrador Sulphur (Colias nastes)
- Canadian Sulphur (Colias canadensis)
- Hecla Sulphur (Colias hecla)
- Booth's Sulphur (Colias tyche thula)
Swallotail (Papilionidae)
Papilio canadensisCanadian Tiger Swallowtail (Papilio canadensis)The tiger swallowtail of the north woods, built for a short summer: one brood a year, a winter spent frozen inside a bark-colored chrysalis, and cater
Papilio machaonOld World Swallowtail (Papilio machaon)The Old World swallowtail is a large yellow-and-black butterfly with a tail on each hindwing and a red eyespot above it, found right across Europe, No- Phoebus Parnassian (Parnassius phoebus)
- Eversmann's Parnassian (Parnassius eversmanni)
Skipper (Hesperiidae)
- Perius Duskywing (Erynnis persius)
- Arctic Skipper (Carterocephalus palaemon)
- Common Branded Skipper (Hesperia comma)
How to identify butterflies in Alaska
With only 80 species the job is easier than in most states, but two groups are hard. The Colias sulphurs overlap in colour and size, and the clues are the shape of the dark border, the colour of the hindwing spot beneath and, above all, habitat: Clouded and Christina's in the lowlands, Palaeno and Pelidne on bogs, Hecla, Labrador and Booth's on tundra. The lesser fritillaries are told by the pattern of the hindwing underside, silver spots for the Silver-bordered, a purplish wash for the Arctic Fritillary, and a plain yellowish ground for the Mountain Fritillary.
The rest is straightforward. A large yellow swallowtail is the Canadian Tiger; a smaller one with a red hindwing eyespot on a hilltop is the Old World Swallowtail; a white butterfly with red spots on an alpine slope is a Phoebus Parnassian, and a yellow one is Eversmann's. Dark butterflies with a cream border are Mourning Cloaks, orange ones with a black-edged band are Milbert's Tortoiseshells, and the butterflies of the United States pages for the northern states show which of these species you may already know from the Rockies or the Great Lakes.
Frequently asked questions about Alaska butterflies
How many species of butterflies are found in Alaska?
Around 80 butterfly species have been recorded in Alaska, the smallest list of any state but Hawaii. Roughly half of them occur around Anchorage and the Chugach Mountains. Most are Holarctic species shared with Siberia and northern Canada, and several, such as Eversmann's Parnassian and the Hecla Sulphur, are found in no other US state.
Does Alaska have a state butterfly?
No. Alaska has never designated a state butterfly. Its official state insect, chosen by schoolchildren and adopted in 1995, is the Four-spot Skimmer dragonfly. If a butterfly were chosen, the Canadian Tiger Swallowtail, the largest and most familiar butterfly in the state, or the Alaskan Old World Swallowtail would be the obvious candidates.
When is the best time to see butterflies in Alaska?
Mid-June to late July is the best time. Swallowtails, parnassians and blues fly in June, the sulphurs and lesser fritillaries peak from late June, and the tundra species on high ridges appear once the snow clears in July. The first hibernating Mourning Cloaks and Milbert's Tortoiseshells can be seen in late April, and almost nothing flies after mid-August.
How do butterflies survive the winter in Alaska?
They freeze. Alaskan butterflies spend the winter as eggs, caterpillars, pupae or, in the case of the Mourning Cloak, Milbert's Tortoiseshell and Green Comma, as adults, all protected by glycerol and other antifreeze compounds that let their tissues freeze without damage. Many tundra species need two summers to grow, so the caterpillar survives two winters before it becomes a butterfly.
How long do butterflies live in Alaska?
An adult Alaskan butterfly lives for two to four weeks, like adults elsewhere; the hibernating Mourning Cloak is the exception and can live about ten months. What is long is the whole life cycle. Because the summer is so short, many arctic and alpine species take two years from egg to adult, spending two winters as a frozen caterpillar.
What is the largest butterfly in Alaska?
The Canadian Tiger Swallowtail is the largest butterfly in Alaska, with a wingspan of about 65 to 85 mm. It is common across the Interior and south-central Alaska in June, when males gather on damp gravel. The Alaskan Old World Swallowtail is slightly smaller, and the two parnassians are the largest white butterflies in the state.
What is the Phoebus Parnassian?
The Phoebus Parnassian (Parnassius phoebus) is a white, red-spotted member of the swallowtail family that flies on alpine slopes in Alaska in June and July. Its caterpillars feed on roseroot stonecrop, and mated females carry a waxy plug that prevents further mating. Its relative Eversmann's Parnassian, with yellow males, occurs in North America only in Alaska, the Yukon and northern British Columbia.
Are there Monarch butterflies in Alaska?
No. The Monarch does not occur in Alaska; there is no milkweed for its caterpillars and the state lies far north of its migration routes. The only regular migrant to reach Alaska is the Painted Lady, which arrives from the south in some summers and breeds briefly on thistles before the cold ends the generation.
Which sulphur butterflies live in Alaska?
Alaska has a dozen Colias sulphurs, more than any other state: the Clouded, Christina's, Palaeno, Pelidne, Giant, Labrador, Canadian, Hecla and Booth's Sulphurs among them. The Clouded and Christina's Sulphurs are the common yellow butterflies of roadsides, the Palaeno and Pelidne fly over bogs, and the Hecla, Labrador and Booth's are greenish tundra species of the high ridges and the Arctic.
Where are the best places to see butterflies in Alaska?
Eagle Summit and Twelvemile Summit on the Steese Highway north of Fairbanks are the classic sites for tundra sulphurs, parnassians and alpines in late June and July. The Denali Highway, Hatcher Pass, the alpine trails of Chugach State Park near Anchorage, Thompson Pass above Valdez and Atigun Pass on the Dalton Highway are the other well-known spots.
Published December 30, 2019 · Last updated September 21, 2026