The Eastern Tiger Swallowtail butterfly (Papilio glaucus) offers a captivating sight for nature lovers. Found predominantly east of the Mississippi river and extending a bit farther west into the Great Plains states, these large insects also make their home in several Mexican states. Their vibrant appearance and widespread presence make them one of the most common and beautiful butterflies of the eastern region.
Sporting a wingspan between 3.12 and 5.5 inches, the Eastern Tiger Swallowtail butterflies are known for their distinct yellow color and striking black stripes. Males embody the iconic yellow-and-black appearance, while females come in two variations – yellow with black stripes (similar to males) or black with darker black stripes. The stunning blue scales on the dorsal side of the hindwings are particularly characteristic of this species and offer a breathtaking visual experience for those lucky enough to encounter them.
Eastern Tiger Swallowtail: Identification
Color and Pattern
The Eastern Tiger Swallowtail is known for its distinctive combination of colors and patterns. Here are some of its visual features:
- Predominantly yellow color
- Four black bands on front wings
- Black border on both wings with a row of yellow spots
- Some individuals have small blue and orange spots near the edge of the hind wings
Click here to view the comparison table
|Eastern Tiger Swallowtail
|Black bands on wings
|Black border with yellow spots
|Blue and orange spots
Size and Wingspan
The Eastern Tiger Swallowtail is a large butterfly species. Its key measurements include:
- Wingspan range of 7.9 to 14.0 cm (approx. 3.12 to 5.5 inches)
This makes the Eastern Tiger Swallowtail one of the most recognizable and admired swallowtail butterflies in the eastern United States, often found in butterfly gardens and treasured by young collectors.
Distribution and Habitat
The Eastern Tiger Swallowtail (Papilio glaucus) is a beautiful and common butterfly, typically found in various regions of North America. They are concentrated mostly in the East, particularly along the Mississippi River and the Appalachian Forests 1.
- Eastern US: Populated areas extend from the Mississippi River eastward
- Appalachian Forests: Dense presence in these mountainous woodlands
Additionally, Eastern Tiger Swallowtails have populations that stretch a bit farther west, into the Great Plains states 2.
- Great Plains States: Spreading westward from the Mississippi River
Overall, the Eastern Tiger Swallowtail’s habitat includes forests and wooded areas, where they have access to nectar-rich flowers and host plants for larvae 3.
Comparison Table: Eastern Tiger Swallowtail Distribution
|North America – East
|Forests, near the Mississippi River
|Mississippi River states, Appalachian Forests
|Great Plains states
Life Cycle and Development
The life cycle of the Eastern Tiger Swallowtail butterfly begins with eggs. Female butterflies lay tiny, spherical eggs that are greenish-white in color. These eggs are laid singly on the leaves of host plants, such as wild cherry and tulip trees.
Upon hatching, the caterpillars of the Eastern Tiger Swallowtail start feeding on the host plant leaves. As they grow, they pass through five instars or developmental stages. Early instars are bird dropping mimics, helping them avoid predators:
- First instar: black with a white saddle
- Later instars: green with two large, false eyespots
Caterpillars undergo considerable growth during these stages and ultimately reach a length of up to 2 inches (5 cm) before entering the chrysalis phase.
In the chrysalis phase, Eastern Tiger Swallowtail caterpillars undergo metamorphosis. They attach themselves to a twig or stem, forming a protective shell called chrysalis. During this time, the caterpillar transforms into an adult butterfly. Some Eastern Tiger Swallowtails overwinter as chrysalises, while others complete this process within a few weeks.
Once the metamorphosis is complete, the adult Eastern Tiger Swallowtail butterfly emerges from the chrysalis. The adult butterfly has a wingspan range of 7.9 to 14.0 cm (approx. 3.12 to 5.5 inches). They are easily recognizable by their vibrant yellow color and black bands on the front wings.
Comparison of Life Cycle Stages:
|Tiny, greenish-white, laid singly on host plant leaves
|Mimics bird droppings, goes through five instars
|Protective shell, metamorphosis occurs, some overwinter
|Vibrant yellow color, black bands, wingspan of 3.12-5.5 inches
Diet and Host Plants
Plants for Caterpillars
Eastern Tiger Swallowtail caterpillars primarily feed on host plants such as:
- Tulip tree (Liriodendron tulipifera)
- Wild cherry (Prunus serotina)
- Cottonwood (Populus deltoides)
- Willow (Salix species)
These host plants serve as essential food sources for the caterpillars to develop into adult butterflies. Some caterpillars may also feed on species like black cherry, birch, and ash trees source.
Nectar Sources for Adults
Adult Eastern Tiger Swallowtail butterflies seek nectar from various flowers as their primary food source. Some popular nectar sources include:
- Milkweed (Asclepias species)
- Lilac (Syringa species)
- Joe Pye weed (Eutrochium species)
- Phlox (Phlox species)
These nectar flowers not only provide nourishment for the adult butterflies but also attract them to gardens and natural landscapes source.
|Tulip tree (tulipifera)
|Wild cherry (Prunus serotina)
|Cottonwood (Populus deltoides)
|Joe Pye weed (Eutrochium)
|Willow (Salix sp.)
By planting a mix of host plants and nectar flowers, you can support both the caterpillars and adult Eastern Tiger Swallowtails, promoting a healthy butterfly population in your area source.
Predators and Defense Mechanisms
Eastern tiger swallowtail butterflies face several predators in their natural habitat, including but not limited to:
- Praying mantises
These predators often target the caterpillar stage of eastern tiger swallowtails, looking for an easy meal.
Mimicry is a common defense mechanism used by eastern tiger swallowtails and other butterfly species. For instance, the eastern tiger swallowtail mimics the pipevine swallowtail, a butterfly species with a toxic defense. By resembling this toxic species, eastern tiger swallowtails deceive predators into avoiding them.
Another example of mimicry is the black swallowtail, which resembles the poisonous monarch caterpillar. This resemblance helps deter predators from consuming them as they mistake them for the toxic species.
Eastern tiger swallowtails rely on the presence of false eyes to deter potential predators. These false eyes are often found on their hindwing, providing the appearance of a larger, more intimidating creature.
|Eastern Tiger Swallowtail
|Mimics Pipevine Swallowtail, False Eyes
|Mimics Monarch Caterpillar
Conservation and Pollination
Importance of Eastern Tiger Swallowtails
The Eastern Tiger Swallowtail (Papilio glaucus) plays a vital role in pollination due to its wide range of host plants. These butterflies serve as excellent pollinators for numerous flowers and trees.
- Pollination: Helps in plant reproduction and food production for humans and wildlife.
- Ecosystem: Positively impacts biodiversity and supports a healthy ecosystem.
For instance, Eastern Tiger Swallowtails can be observed visiting plants like milkweed, dogbane, and various fruit trees.
However, the butterfly faces challenges due to habitat loss and pesticide exposure.
- Create butterfly-friendly gardens, providing nectar-rich flowers and host plants.
- Limit or avoid using pesticides in gardens and landscapes.
- Participate in citizen science projects to monitor butterfly populations.
|Eastern Tiger Swallowtail
|3.1 – 5.5 inches
|Eastern North America
|Pesticides, habitat loss
By supporting the conservation of the Eastern Tiger Swallowtail, we ensure their continued contribution to pollination and a balanced ecosystem.
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Eastern Tiger Swallowtail: Bilateral Gynandromorph
Subject: Butterfly question
Location: Morganton, NC
September 14, 2013 12:37 pm
I took a picture of a butterfly over the labor day weekend in Morganton, NC. The butterfly has 2 different wings, one is black, the other is yellow. I posted the picture on a Facebook photography page. Someone replied that it was a tiger swallowtail hermaphrodite, bilateral gynandromorph.
I would love to learn more information about the butterfly. If you have any information, I would greatly appreciate it. I can email you a picture of the butterfly or you can view it on my Facebook page.
Waiting to hear from you. Thanks, Sandy Sisk
Signature: Sandy Sisk
Thank you for sending us your wonderful photo of a very asymmetrical Eastern Tiger Swallowtail, Papilio glaucus, but we are not fully convinced it is a true gynandromorph like this example of a Tiger Swallowtail gynandromorph we have in our archives. Male and female Tiger Swallowtails can be distinguished from one another by the blue markings on the lower wings of the females. Your individual appears to us to be a dark female on the left and a light female on the right since there are blue markings on both hindwings. See BugGuide for an explanation of the sexual dimorphism of Eastern Tiger Swallowtails. Some female Tiger Swallowtails are transitional morphs, that are not light nor dark, but your individual is an unusual bilateral morph. We are going to seek the opinion of lepidopterist Julian Donahue to see if he believes this is a gynandromorph. More information on gynandromorphs can be found on the Dalton State website.
Julian Donahue’s Assessment: Bilateral Gynandromorph
It’s almost a perfect bilateral gynandromorph. But because of the unusual markings on the UPH on the right side, it may perhaps more properly be called an intersex, or a color mosaic. While bilateral gynandromorphs are most striking, all sorts of confused mosaic patterns have been documented.
I’m attaching a PDF of an article on this very subject, with color photographs of many examples, by Mr. Tiger Swallowtail himself, Dr. J. Mark Scriber. You can also link to the PDF at:
Letter 2 – Eastern Tiger Swallowtail
Close up image of a Tiger Swallowtail
Hello, I’ve seen mentioned more than once in this site that your local Swallowtails are camera shy. This one certainly wasn’t. The image was taken in (northern)Illinois on a plant called Tithonia, aka "Mexican Sunflower" (though it is not a helianthus), an excellent beacon for butterflies, hummingbirds and the like. This image has been cropped, but the full-size image makes a wonderful background for a computer screen. Thank you for providing an informative site.
Thank you for the wonderful photo of an Eastern Tiger Swallowtail, Papilio glaucus.
Letter 3 – Eastern Tiger Swallowtail
Eastern Tiger Swallowtail
Hello Mr. Bugman.
Just going through my portfolio of butterfly pictures and thought this was a pretty good profile picture of an Eastern Tiger Swallowtail. Didn’t know if this would make the grade for displaying on you web site. If you think your viewers might enjoy this beauty then feel free to use it. You probably get hundreds of this very common butterfly. Saw my first butterfly here in Charlotte, NC on March 23. It was in my yard and I startled it when I walked by and watched it fly away but could not tell what kind it was. I am anxious to start photographing some of these early flyers. Loyal observer of your web site,
It is nice to find out about loyal observers to the site. Often when people go through their archives, they send photos that were taken years before and in different seasons. We like posting images that people are likely to encounter when the image is posted. The Eastern Tiger Swallowtail should be making appearances in the southernmost reaches of its range right now. Our own Western Tiger Swallowtails have been soaring in our own Mt Washington, Los Angeles garden. We have seen at least three individuals as well as numerour Anise Swallowtails. Our other swallowtail visitor, the Giant Swallowtail, has recently expanded its range to our vicinity, but it appears in the warmer months. We watched two Red Admirals frolicking about yesterday in the late afternoon sun. We haven’t seen any Mourning Cloaks this year, which is unusual. Thanks for your contribution.
Letter 4 – Eastern Tiger Swallowtail
Subject: Western Tiger Swallowtail…I think
Location: Kent City, MI
September 17, 2012 10:20 pm
You can add this to the picts you were asking for…
Pretty sure she is a Western Tiger Swallowtail.
Thank you for submitting your lovely photos of a Tiger Swallowtail. North America has at least five identified species of Tiger Swallowtails, but two can definitely be eliminated, including the Western Tiger Swallowtail, which according to BugGuide, ranges in: “Western North America east to the edge of the Rocky Mountains.” Michigan is an area where the ranges of two species, the Canadian Tiger Swallowtail and the Eastern Tiger Swallowtail, overlap, and the two species are closely related enough to interbreed, creating hybrids. Since there is no blue on the hind wings, we believe this is a male Eastern Tiger Swallowtail, Papilio glaucus, and you can read more about it on BugGuide.
Letter 5 – Eastern Tiger Swallowtail: What's In a Name???
Subject: Tiger Swallowtail – Papilio glaucus or Pterourus glaucus?
Location: Naperville, IL
July 10, 2012 10:15 pm
These photos are of a female Eastern Tiger Swallowtail, but do you know which genus name is correct? We’ve had some intense heat in Illinois over the past two weeks, which finally broke a few days ago, and I am thinking this might be why I’ve seen so few butterflies about. Is there any basis to this? All the best to you.
Signature: -Dori Eldridge
You have proposed a very interesting theoretical question. The reason we have scientific names for insects as well as all other known life forms on this planet is so that there is a universal name for the creature regardless of the language spoken by the person who is referring to the creature. The common names are less widely used and often the same common name might be used for a number of creatures just as the same creature, especially if it has an extensive range, might have numerous common names. There are also officially recognized common names as well as casually used common names that are not officially registered. Since your question is regarding the scientific binomial name, we will confine the remainder of our response to that nomenclature. How is a scientific name determined? BioDiversity Explorer has a very extensive explanation on the process. So, how can a species have more than one scientific name? The first person who describes a species has naming rights, but in the days prior to the instantaneous mass communication we have at our fingertips today, it was possible to have more than one person simultaneously discover a species, or especially in the case of wide ranging species, to have a subsequent person believe that person has discovered a new species when it was previously described. In that case, even if the second name came into wide use, the first naming trumped. It is also possible that a species was originally placed in one genus and further scientific investigation caused the genus to be either split or lumped, necessitating a change in the genus name which is the first and capitalized part of the binomial. Until your letter, we were unaware of any scientific name for the Eastern Tiger Swallowtail except Papilio glaucus. Your question caused us to do some research. BugGuide still has the Tiger Swallowtail listed as Papilio glaucus, however, however it is indicated: “Synonyms and other taxonomic changes
Papilio glaucus Linnaeus, 1758. Synonyms and taxonomic notes:
Pterourus glaucus–sometimes this and related species are split out from Papilio.
Large, spring-flying populations in the Appalachians have recently been recognized as a separate species, Papilio appalachiensis (Pterourus appalachiensis).”
The North American Butterfly Association (NABA) still recognizes Papilio glaucus. The modern use of DNA analysis can have a significant bearing on the naming and renaming of new and known species. Finally we turned up this online version of The Taxonomic Report of the International Lepidoptera Survey from 15 June 2002 that recognizes Pterourus appalachiensis as “a new swallowtail butterfly from the Appalachian region of the United States.” Perhaps the discovery of that species is responsible for splitting out the Tiger Swallowtails from the genus Papilio. We must confess Dori, that we are not scientists and you should probably check with a noted expert in the field before trusting anything we have discovered.
Letter 6 – Eastern Tiger Swallowtails
Geographic location of the bug: Campbell, Ohio
Time: 5:58 PM EDT
The Swallowtails visiting Daniel’s Ohio garden have been spectacular this year, but they were pretty spectacular last year as well.
Within a half an hour of one another one evening, Daniel spotted this male Eastern Tiger Swallowtail nectaring on the butterfly bush Daniel planted last summer, and then a female Eastern Tiger Swallowtail (she has blue scales on her underwings and he does not) nectaring from the large thistles Daniel is allowing to grow. The Eastern Goldfinches are having a field day eating their seeds.
A week later, Daniel dug from his friend Hector’s wild garden, some Joe Pye Weed, Ironweed and Teasel, all attractive to pollinating insects, and the very next day, on August 12, this very tattered female black Eastern Tiger Swallowtail enjoyed the Joe Pye Weed for about a half an hour. As though she knew she was safe, she allowed Daniel to get quite close and as he got a really good look at the state of her wings, he couldn’t help but to wonder “How ever can she fly?”
Letter 7 – Eastern Tiger Swallowtails Puddling
Subject: Papilio glaucus
Location: Nathaniel Boone Forest State Park
March 19, 2014 11:01 am
These pics of Eastern Tiger Swallowtails were taken along a trail in the Nathaniel Boone Forest State Park outside of Camden TN. It was late June I believe when I took the pic. They were feeding on dung or rotting fruit.
Hi again Swampyy82,
Thanks for sending us this gorgeous image of Eastern Tiger Swallowtails congregating at a moisture spot, an activity that is commonly called mud-puddling or just puddling. More information can be found in an Ecological Entomology article written in 1991 by Carol L. Boggs and Lee Ann Jackson called Mud puddling by butterflies is not a simple matter. They wrote: “Adult Lepidoptera of many families feed from puddles, carrion and excreta (Norris, 1936; Downes, 1973; Adler, 1982). Such behavior is termed ‘puddling’, and may involve aggregations of individuals feeding at a location which is used repeatedly. the participants are usually male and often young (e.g. Collenette, 1934; Adler, 1982; Adler & Pearson, 1982). … Sodium, which may be an otherwise scarce nutrient in the adult diet, triggers puddling behavior, at least in “Papilio (Arms et al., 1974).”
Letter 8 – Female Eastern Tiger Swallowtail
Location: Middle Tennessee
September 2, 2013 12:04 pm
This swallowtail was lazily flying around in the back yard in Middle Tennessee(Murfreesboro) today so I had time to run for the camera, I just wanted to share this awesome butterfly with you.
Is it a male or female?
Signature: Rae Nichols
Though Tennessee is a state where the range of the Eastern Tiger Swallowtail and the Appalachian Tiger Swallowtail overlap, we believe you have a photo of an Eastern Tiger Swallowtail, Papilio glaucus. Your individual is a female as evidenced by the blue pattern on the lower wings. According to BugGuide: “Light phase females show blue on hindwing above.” This photo of a female Eastern Tiger Swallowtail from BugGuide illustrates the blue markings.
Letter 9 – Female Eastern Tiger Swallowtail
Subject: Bug identification
Location: Munhall PA 15120
November 10, 2016 6:07 pm
This bug appeared on my watering vase when watering my yellow mums.
The small colorful moth is an Ailanthus Webworm, and your other image appears to be a dead female Eastern Tiger Swallowtail, based on the blue coloration on the hind wings, as depicted in this BugGuide image.
Letter 10 – Female Eastern Tiger Swallowtail: Dark Form
spicebush pipevine pipebush spicevine I need help
I have tried to find a way to identify the difference between a pipevine and a spicebush swallowtail but I’m kinda stupid at it. I’m worried that some folks online don’t have it right, as there seem to be conflicting reports. This picture was taken in Central Kentucky. Help me Obi-Wan Kenobugman, you’re my only hope.
Drew in Scotland (where there are no swallowtails)
Neither is correct. This is an Eastern Tiger Swallowtail, Papilio glaucus. Some females, especially in the southern part of the range, are dark. The tiger pattern can still be distinguished as the lighting on your photograph nicely illustrates.
Letter 11 – Female Eastern Tiger Swallowtail: Not quite light form and not quite dark form
really really need to identify, i think it may be unknown
I have looked everywhere, all on your website, every website with swallow tails, I CANT FIND IT ANYWHERE! please help! I live in Vermont so there is only a few species of swallowtails around here in concord VT.
We believe this is a female Eastern Tiger Swallowtail, Papilio glaucus. The female Eastern Tiger Swallowtail has both a light form and a dark form. BugGuide has one photo of an intermediate, but the dark areas are close to the center of the body. We believe that you have one of these intermediate forms, but we relish a true expert confirming our suspicions. If we are correct, you have a truly unique find.
im confused, intermediate? So its a little bit between the two, the dark form and light form? It is very unique, and thank you so much for helping, is there any other source you could give me to verify your findings? Thanks
Somehow, additional searching on BugGuide revealed a near exact match, also listed as an intermediate between the light and dark forms.
Letter 12 – Eastern Tiger Swallowtail
Subject: Eastern Tiger Swallowtail
Location: Perinton, NY
August 15, 2016 6:42 pm
Hi! Here are some pics of an Eastern Tiger Swallowtail on the right-of-way behind our home. I believe it’s a male, as I didn’t see any blue on the hind wings. We’ve had an amazing variety of butterflies here this year, more than in years past. Enjoy!
You surely are providing us with some wonderful eastern butterfly images. Because of your location, we cannot say for certain that this is an Eastern Tiger Swallowtail, Papilio glaucus glaucus, since the range of the Canadian Tiger Swallowtail, Papilio canadensis, can be as far south as Pennsylvania. The two species look very similar and this BugGuide differentiation and description of the Canadian Tiger Swallowtail “adult: inner margin of hindwing has wide black stripe (whereas the otherwise similar – though larger – Eastern Tiger Swallowtail has a thin black stripe in that area)” seems vague, as does the comparison of images on the Canadian Biodiversity Information Facility site. We do agree it is a male. Perhaps one of our readers will write in with a more concrete species call than we are able to provide.
Thanks to a comment from Cesar Crash, we will concur that this is an Eastern Tiger Swallowtail.