Raising Eastern Black Swallowtail Caterpillars

Every year for nearly thirty years now I enjoy the ritual of raising Monarch caterpillars and observing them throughout their astounding metamorphosis. This year as I eyed an Eastern Black Swallowtail (Papilio polyxenes Fabricius 1775) fasten an egg to a tiny Queen Anne’s Lace plant . . .  hidden within some horrid Bishop’s Weed . . . I thought I might like to get to know the offspring of this butterfly too.

It is a good year for Queen Anne’s Lace flowers in the fields. I know I should mow the flowers down, for the European introduced ‘Wild Carrot’ can be very invasive. I confess to letting them grow some years, as the plant and flowers are host to Eastern Black Swallowtail. They will gladly eat any plant in the carrot family. The tiny cream colored egg of the Swallowtail is like a jewel on a thread of leaf.

In the center of most of the lacy flowers there is a dark spot. When the caterpillar first emerges it reminds me of that little speck of black. There is a thin lace colored stripe on the larva. It certainly reminds one a bit of bird poop too. Nature is a wonder in creating camouflage garb.

I had my little Black Swallowtail ward in a separate container next to my Monarch caterpillar family. It is fun to observe the difference in how these two captives devour their hand-harvested food. The Monarch eats to grow FAST, where the Swallowtail takes its time . . . after all . . .  it has no reason to hurry . . . no long journey ahead . . . a long winter sleep within its chrysalis, while the Monarchs take a perilous flight to Mexico. I collected the eggs of both butterflies at about the same time. The Monarch instars morphed many times while the Swallowtail remains content to stay smaller in its early instar suits much longer. The Swallowtail first instar is only about an eighth of an inch long in the photo above. It stayed on one flower for several days munching on the teeny petals . . . one by one.

The Eastern Black Swallowtail morphs into a differently designed instar. Its new third instar coat is like armor complete with many spikes of bright orange. Perhaps more frightening to predators than the smaller brown barbs on its former dress.

By the fourth instar the Eastern Black Swallowtail becomes more fond of green and has less prongs. It is at about this stage that the caterpillar truly begins to acquire a taste for food and even devours the stem of its host plant.

The fifth instar in all its splendor.

I never disturb this little one enough for it to bark at me with its vibrant orange organ known as an osmetrium. You can almost see the bit of orange on its head. If alarmed . . .  a long forked-like antennae emerges and is warningly wiggled towards the intruder.

This photo reminds me of the very full caterpillar in ‘Alice In Wonderland.’ Over three inches about this time, and when I came home from a concert, a large poop . . . I mean LARGE . . .  was on the floor below the pedestal it grew up on. I found the caterpillar half its former size spinning a silk line on a sedum stem. It seems they empty out their entire digestive system before resting and forming the pupa. Our liaison has come to an end. Truthfully it takes very little effort to raise the Eastern Black Swallowtail . . . and . . .  well, I do not mean to complain, but unlike the very demanding Monarch caterpillars, I did not have to run out into the field or garden paths daily to fetch fresh lace, as I do milkweed for my Monarch wards. I do dote on them and cannot imagine my life without the sprightly Monarch critters . . . but that is another story.

Letting Go!

The next day a beautiful green and yellow chrysalis hangs . . . no roaming for this larva . . . the lodging right next door seems safe enough. Note below that the Eastern Black Swallowtail was going into its chrysalis stage, as the Monarchs were already becoming butterflies and some had already taken their first flight. A Monarch caterpillar from an egg brought in much later than that of the Swallowtail is about to make its silk node and hang towards its becoming a chrysalis. It was quite delightful observing this process of life and I look forward to sharing the winter nest with the sleeping slowly forming butterfly. I will be sharing other butterfly tales later on. The metaphor of their metamorphosis to our human lives always moves and inspires me. I am very respectful of my wards and have them all growing next to open windows. I even hold them out under the rain so they can sense the changes in nature. I share this magic with all my guests and enjoy seeing the joy and awe in those seeing these life forms and their transformations for the first time.

I want to end this piece by saying that I do not support the commercial selling of eggs, caterpillars or butterflies. I believe we should only raise larva in the area they were found in. I think that buying and releasing butterflies at weddings should be a crime. It is cruel and potentially can affect the butterflies living naturally in any one region. Enjoying wildlife in its habitat and thoughtfully raising and releasing them back is a safer saner way to enjoy and learn more about wildlife. I often feel guilty even bringing in the milkweed plants that are in harms way growing in the garden paths. Perhaps I am wrong about this way of thinking . . . in regards to city classrooms all over the country who raise and study Monarchs and Silk caterpillars . . . I suppose the jury is still out. It is a precious thing for every child to be able to see a butterfly fly for the first time. Milkweed does even grow in city cracks. I would love to hear what you think. I do not mean to be unfair in my judgement. I am lucky to have twenty-one acres to explore.


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  1. says

    Carol I am unsure about the raising of caterpillars not naturally found although if a habitat can sustain them and they need our help then I think it would be OK. I have never had the time to watch this wonderful metamorphosis. One goal I have made for myself next year it to target monarchs and Easter Black Swallowtails and see if I can spot them in the meadow and garden. I have plenty of Queen Anne’s lace to support them and have cultivated the milkweed. This post certainly will help me so thx loads. As always I am amazed at the photos…wonderful!!
    Donna@ Gardens Eye View recently posted..Success

  2. says

    We had one living and feasting on a 2nd-year parsley plant earlier this summer. I put some chicken wire around the plant to try to protect it from predators. After a couple of weeks it was gone. I prefer to leave them in their natural habitat, yet I was thinking twice about that when this one disappeared. I hope it crawled off somewhere to make its chrysalis instead of getting eaten by something.

    Wonderful photos – must be such a joy observing them as they grow and change, and as they emerge from their transformative sleep.
    Linda recently posted..Veggie Gardens Video Tour

    • says

      It is a joy Linda. I hope your caterpillar did become a chrysalis too. You are so dear to protect it that way, unfortunately the wire would not keep out spiders or many other little critters that like to munch on caterpillars. Wrens might get right through too. I often check on the Monarch caterpillars out in the garden . . . there are many that are not in the paths and so I let them be. I often find spider webs on the underparts of the milkweed leaves and see wrens going to and from all the plants. I have even seen wasp carrying off the tiny instars. Mostly I can never find the caterpillars. Such is nature and the food chain. ;>( Still millions make it each year to fly to Mexico. I have read that Monarchs are down this year. Five flew out of my window today. ;>) Hopefully they will survive the birds! Thanks so for visiting and sharing. Carol
      Carol Duke recently posted..Silent Verdurous Studies Fluid Hummers Asclepias Leafy Landscape Inhabitants

  3. says

    I’d like to correct your spelling of the word, “osmeterium.” These fleshy orange organs protrude and emit an unpleasant odor when the caterpillar feels threatened. I have raised many E. Black Swallowtails during the past 9 years, which is the time I have also been selling the adults to people who release them at special occasions. Since butterfly farmers can only sell and ship USDA-approved species, there is no harm in releasing a butterfly in a place where it did not originate. It is not a cruel practice; in fact, it is uplifting and joyful for the participants, in addition to help repopulate the species. Butterfly farmers are regulated as to which species can be released. All need to be indigenous to the place where they are released. Many people make their living by carefully raising and selling butterflies for release. You are entitled to your opinion, but as a long-time butterfly farmer, I have studied butterflies for many years and would never do anything to harm these beautiful creatures.

    • says

      Thank you Linda!
      I am not sure of your practices in raising caterpillars and then shipping butterflies, but I have read and heard first hand accounts of butterflies being injured during the shipping process, not to mention the trauma they must suffer. Frankly, putting a butterfly into an envelope and packing it however one does, when it is truly ready to fly seem cruel to me. When a butterfly emerges from its chrysalis and hangs for the needed time to dry its wings and adjust to all its new parts, it is ready to fly. Fly . . . not be stuffed into a sleeve and packed for shipping somewhere. I think this is morally wrong. I find it joyful to release a butterfly and cannot understand how others would want to put a butterfly through such manipulation and often death just so they can release them at their wedding or any occasion. Butterflies are alive and feel . . . they are not balloons or rice or flower petals. I am sure you mean well but this is not a process that is kind to wildlife. It is exploitive and yes I suppose that my bringing them in at all is also. The difference is that as soon as my wards are ready to fly they can and into the sky. I think it is great to talk about this no matter we may disagree. I would imagine your butterfly farm offers many great opportunities to your local community . . . such as learning more about these precious insects. Thank you for sharing.
      Carol Duke recently posted..Silent Verdurous Studies Fluid Hummers Asclepias Leafy Landscape Inhabitants

  4. says

    Carol, what a wonderful experience to be able to compare the life cycle of both the Monarch and the Black Swallowtail! Your photos, as always, are simply stunning :). I agree with you about the sale of butterflies around the country. There is some evidence that this practice is causing the spread of viruses and diseases from one population to another.
    Carole Sevilla Brown recently posted..Lets Just Eat the Invasive Plants

  5. says

    How lovely! I know there are lots of black swallowtails around, but none of the caterpillars made their way into the garden this year…and a mantis got my spicebush swallowtails. Still, circle of life and all that. (One of these days I want to have a caterpillar make it all the way in the garden! Just one where I can see it! That’s all I ask!)

    I don’t see any real problem with taking local caterpillars and raising them to butterflies, as you’ve done there, but definitely importing them is rather questionable–you might bring in diseases or affect local gene pools negatively. But I think it’s useful for kids to watch a caterpillar in action in the classroom, too, and if it helps them get invested in nature, that’s potentially very useful. So it’s definitely a mixed bag.
    UrsulaV recently posted..Io Moth Caterpillar

    • says

      Thank you Ursula! Yes, I know what you mean about caterpillars surviving all the many predators out there. Perhaps that is why butterflies usually lay up to 500 eggs. So many do not survive. I hope you get to see a caterpillar become a chrysalis too! I agree about the kids and how their seeing this magical process can so inspire them towards caring for nature and wildlife. I would imagine there are better ways to carefully pack the eggs and ship those instead of the caterpillars. It seems odd a bit . . . I guess . . . to be thinking a long these lines when there are so many larger issues of suffering and injustice the world over. Maybe if we showed more compassion towards all life forms we might be kinder towards each other. One can dream. Thanks so much for sharing!
      Carol Duke recently posted..Silent Verdurous Studies Fluid Hummers Asclepias Leafy Landscape Inhabitants

  6. Pauline Horn says

    I’ve never actually raised them, but I have enjoyed watching them eat my parsley and my dill for many years. I finally found two native plants that they will eat Zizia aptera ( heart-leaved meadow parsnip or alexander) and zizia aurea (golden alexander), and am waiting for the butterflies to find them. Unfortunately I have had very few butterflies this year, so I may have to wait until next year. I’ve also done the same with milkweeds for the Monarchs. Initially I tried Common milkweed (Asclepias Syriaca), but found it much too invasive. Since then I’ve planted swamp milkweed (Asclepias incarnata), purple milkweed (asclepias purpurascens), butterflyweed (asclepias tuberosa), and whorled milkweed, all with much happier results.

  7. Pat Schubert says

    This year I had the joy of raising 10 monarchs and 2 black swallowtail caterpillars that surely would have been food for the many predators bugs and birds we have in the garden. Most neighbors here don’t plant gardens for butterflies or caterpillars to live in. We have an oasis of plants for food and nectar for some of them.My goal is to make a home for the every day common butterflies that once lived here. It’s interesting to find out what different butterflies need for a habitat in which to thrive. Thank you for the beautiful photos. They are awesome!!!!!!!

  8. says

    Thank you Pat! Maybe you will be an inspiration for your neighbors. Hopefully a new corridor for wildlife will develop in your part of the world. I like to imagine front yards across the world becoming life giving corridors for all kinds of wildlife. No more lawns. ;>) Thanks so for all you do for our wildlife, for sharing and for your generous supportive words.
    Carol Duke recently posted..Silent Verdurous Studies Fluid Hummers Asclepias Leafy Landscape Inhabitants

  9. says

    Great article Carol. Thanks for sharing this experience, I felt like I was there.

    As to commercially raising butterflies for release at the whim of humans, I’m against it. We wouldn’t raise puppies or polar bears and randomly release them, so why is it different with our winged friends? However, I do think that limited captive raising of locally caught butterflies in the interest of education is important as it molds the nature lovers of the next generation (and even some of the current generation).

    My black swallowtails use Florida Native WATER COWBANE (Oxypolis filiformis) as their larval host and I’ve been blessed with being able to follow along on their journey in the wild setting.
    Loret recently posted..Tribute to a Great Friend

  10. says

    I just posted a comment on Benjamin Vogt’s article about monarchs and Liatris…lamenting that my managed population of common milkweed does not bring many monarchs. The comments on your article make me think maybe I do have monarch eggs and larvae, but also many spiders, wasps, and small songbirds of all kinds foraging in my meadow. Predators (bless them, too) had not really occurred to me…

  11. says

    Ruth, there are many predators of the Monarch caterpillars and their eggs . . . it is true. Even the red Milkweed beetles will eat the leaves eggs and all. The ivory colored casings are very tiny and hard to find. You might find a magnifying glass helpful . . . I often find eggs on younger leaves. Good Luck finding some in your Milkweed. Thanks so for sharing.
    Carol Duke recently posted..Deeper Into Green A Monarchy Morphs

  12. says

    I am glad I found this site Carol. Thank you so much for the information & lovely photos. My mother-in-law was given a monarch cat in a clear plastic container to feed and watch its metamorphosis. She obtained milkweed from our property (66 acres wetland & 34 forests & meadows) as she wanted pesticide free milkweed. She could have released it in the city, but released it at our place so it would have food in its purest form. I have a butterfly friendly garden and have grown fennel (bronze) in hopes of attracting Black Swallowtails. This year I saw one briefly, but then on the weekend there were 4 Black Swallowtail cats of different sizes munching away on the fennel. My mother-in-law took one home to nurture. My in-laws are in their 70’s and have been introduced to nature since we bought our ‘swamp’, and are amazed at the biodiversity of the area. We bought the property 5 years ago and most people including our family & realestate agent did their best to dissuade us. Having read your info about an overwintering chrysalis, I’m wondering if we did the right thing …… your advice would be greatly appreciated. Thank you, Cheryl

  13. Ben says

    Hi Carol! I found your article via a google search for information on the eastern swallowtail caterpillar. And what a wonderful find it was! Your piece was simply fantastic. Very well written, gorgeous photos, informational, modern, inspiring…I could go on. Thank you for putting together such a great publication for our enjoyment. Keep up the great work! All the best!

  14. beth lehman says

    As a teacher, I have LOVED watching the interest children take in nature – it’s wonder – when having Monarchs in the classroom – I have mixed feelings myself but feel like it’s such an amazing thing to observe. My own children adore watching the process unfold and I was led to your blog after a google search – as we ended up with an Eastern Swallowtail this year after a hike on the AT. We also had tags from KSU that we tagged a monarch with. Thanks for your great photos – it helped ID our little guy! What should we do after chrysalis stage? Will they stay this way throughout winter? Then I’d imagine we shouldn’t keep it inside.

  15. says

    Beth, I too think it is wonderful to share this wonder of metamorphosis and the whole amazing story of the Monarch butterfly with children of all ages. I am sure it must be so heart-warming to see their awe in your classroom. I do really have mixed feelings about all the tagging that goes on though. As for the Black Swallowtail . . . it is hard to say. I thought my little guy was going to be a winter studio mate but it seems he decided to come out just recently. My next post here will be about just that. I would say look for any changes in the chrysalis and if you begin to see the butterfly inside you will be close to seeing it emerge. The ones that go into a chrysalis later like now, I guess, will winter over. Mine became a chrysalis in August. Good luck with it. Thank you so for sharing and for your kind words.
    Carol Duke recently posted..Wild Skies, Plants and Butterflies Inside and Out

  16. beth lehman says

    Carol – thanks for writing again! I can’t wait to see more pictures. Ours was “captured” last Sunday here in Virginia (by my own kids and husband, and father-in-law). It is still lazily eating queen anne’s lace, having eaten about three complete flower heads. It seems lathargic next to a monarch! It is probably in it’s last instar stage b/c it seems pretty big to me. I guess if it cacoons before September is over, we might be able to release it, but if not, I think we’ll put it outside somewhere? (Maybe we should have left it…!!) I have to say with my work experience – even many families who spent time outdoors really don’t have an appreciation for nature. So, when I have been able to see kids being absolutely amazed by nature – I hope that the experience is one they will carry into adulthood – I’m hoping seeing the metamorphasis translates into their living more simply – with nature and the environment seen as something they influence… (wishful, but powerful!).

    • says

      Beth, It is so important that children have an adult who shares the magic found in nature. You are right that these early experiences may stay with them all their lives and help them to see how necessary it is for us all to explore and protect the natural world. Thank you for your comments.
      Carol Duke recently posted..Beauties of the Night ~ Luna Moth

  17. Anna Galea says

    I sort of agree with Linda’s view on raising butterflies naturally. I have to admit that raising them online is so much easier, and you don’t have to wait so long to find them (for impatient people like me…), so I can’t really say if it’s BAD or GOOD, but I just can say that finding them in nature is much more exciting! I still remember the first caterpillars I had. I was a young girl then, about 11-13, I don’t remember exactly, and I had bought them online. They were monarchs and I waited so long and when I finally got them, I was so happy. I remember waking up at 6am to see if they hatched. So one day they did. They were like my tiny little children. I was really happy but after two whole weeks, I noticed that they weren’t growing. They were STILL my tiny babies… hardly bigger than 1 millimeter, when they should have already been over 2 inches long. So after this struggle they were having, they finally died, all of them. I was so heartbroken, and I cried for weeks afterwards. It seems they had some strange disease. I finally got back around to raising caterpillars, and the next summer, I successfully raised a hole brood of monarch caterpillars (with the expense of only one- NEVER use duck tape around caterpillars!!!), and these cats were brought in as eggs from the milkweed in my backyard. I don’t really trust online stores. Even if they have pictures up, you never know what the condition of the actual farm is. That doesn’t mean you shouldn’t buy them online, but try to be VERY careful, and only buy species native to your area, to prevent deaths.

    • says

      Thank you for sharing your story Anna. It is not a good idea to buy butterflies or caterpillars from online stores. We might be introducing a disease to our native area by doing so. It is always best to try to find them within our own habitats. I only bring in caterpillars that are on milkweed along our walking paths. I enjoy watching others outside too.
      Carol Duke recently posted..Beauties of the Night ~ Luna Moth

  18. mel says

    This is a great description of the swallowtail. We have had the caterpillars for years munching on our parsley, dill, and fennel. We have noticed that the caterpillars take off when they are ready to pupate and wonder why and where they are going. We have found them walking across our patio, inside our back porch, and in other parts of the garden. Yesterday one was walking up the wall of my house before deciding that was not a good location. Any idea what their preferred chrysalis plant is?

    • says

      Hi Mel, Thanks so for sharing your experience with us. I do not believe cats have a preferred plant to make their chrysalis on. They roam until they find some place that feels safe. (It is rare that they would make a chrysalis on their host plant.) I have found that some just seem to be harder to please. Perhaps they are just uncertain or uneasy and keep searching for that perfect place . . . I hope you were able to see where yours finally settled on so you can keep an eye on it.
      Carol Duke recently posted..Question Marks and Commas ~ Pausing to Ponder

  19. Michelle M. says

    I was wondering if you knew what would happen to the chrysalis if the caterpillar some how managed to detatch itself from the silk nodes while forming the chrysalis. We have one right now that did just that. Thanks!

    • says

      Michelle, If you are speaking of a black swallowtail . . . they do not make silk nodes but do use a silk thread to attach themselves as you can see above. I would try to copy that as much as possible and tie them to a twig or something safe. Monarchs do make a silk node and if they do not attach with their cremaster (the tiny black stem on top of the chrysalis) then I have tied a thread around the cremaster (double knot) and tied the chrysalis to a stem . . . being sure to give enough room below for the butterfly to fall out. It is important to do this as quickly as possible so the chrysalis will fully form. I hope this helps.
      Carol Duke recently posted..Monarch Butterfly Life Cycle: A Metamorphosis ~ Part Two ~ Jeweled Chrysalis

  20. Christi says

    This is my first time raising a caterpillar. We found this little guy and fed him parsley and dill. He ate just fine and was doing great. Then it came time to go to pupate. He climbed the side of the cage and went all over the top of the cage and fell 4 times while I was up that night. He was fine each time and went back up to the top. Then the next morning I found him attached to the roof of the cage.

    Okay so here is the part I’m worried about. While he was alive and moving for a few days. (as I accidentally kept hitting my hand against the cage when I’d go check on him) He started to turn black. (now not black and in black death as he is not shiny black just like grayish black) Now the roof of our cage is black. So could it be camouflage?

    Next as the comment title says, it has now been a week since he got up there. However the temperature has been flexing up here from warm to cold to warm. Is it dead? Does it really sometimes last more than a week or just up to a week.


    • says

      Christi, I am sorry I did not see this sooner. By now you can tell us if the pupa was alive or not. There are some that do turn a dark color, while others Black Swallowtails turn green. The pupa or chrysalis stage may last up to twelve days or so but there can be variations depending on the temperature. I once had a monarch chrysalis that lasted for a month. The butterfly came out in November. So you never be sure. Patience and observation is necessary when raising butterflies. Thanks for your comment.
      Carol Duke recently posted..Beauties of the Night ~ Luna Moth

  21. Lisa says

    great site! this is my first time finding “good” caterpillars in my garden – usually i just get cabbage and tobacco cats. i was planning on squashing these guys when i saw them today, but decided to look them up first. so glad i did! unfortunately, i feed the birds here, so predators abound, but after a few hours research on these critters, i decided to take half of them and build bucket houses for them to over-winter. hopefully all goes well – thank you for you insight!

  22. carol says

    I enjoyed your photos and story of your eastern black swallow tails. I put in a butterfly garden years ago. we have routinely enjoyed watching the monarch, black eastern swallow tail, gulf fritallary and the yellow sulfer butterflys lay eggs, hatch, and grow through all their stages. we would watch every stage in every detail that went with it. somewhere during year two the predators caught on. the wasps have ravaged my sweet garden terribly. I routinely move monarchs and black eastern swallowtail caterpillars on to their host plant in my screened patio so that some will survive. we lose so many to wasps each year I would give it up completely but I always have one boy, who enjoy the ones we save so much that I continue.

  23. says

    I’m a young mother and artist who loves exploring our little bit of backyard nature with my children. I’ve brought an american swallowtail caterpillar inside to try to raise it to adulthood. Right now it is very happy with parsley in a salsa sized glass jar covered with cheese cloth and a piece of paper towel to prevent mold but will it eventually need a larger container? Are there any resources you suggest for learning how to raise butterflies?
    Rebecca recently posted..Drawing is Seeing

  24. Heather says

    HI Carol,

    My daughter found our very first Eastern Black Swallowtail just over a week ago in our back yard. He was already in his 5th instar as I am learning. He went into his chrysilas a couple of days later. I was reading in my daughter’s butterfly book that they stay in all winter. Should I find a safe place outside for him to feel the cold? Or can he stay inside the house without disrupting his process?
    We have raised several monarachs and I was used to them emerging after about 2 weeks, this is all new to me.
    Thank you for any insight you can give me.

  25. Susan Wagoner says

    I have my first black swallowtail caterpillar since childhood… he has formed his chrysalis but it appears to be incomplete as the posterior end shows the pattern of the caterpillar…that is one concern. The other is overwintering… since it just formed its chrysalis now in August will it be overwintering? (Do the ones earlier in the year emerge?) I live in Illinois and if I keep it inside it may be too warm? A friend said she had one emerge in October or November when it was obviously too cold for the butterfly. What if I keep the jar out during winter?
    I hope to be better prepared the next time with a larger box and fancier “digs”… any suggestions for what to do when they get “hyper” looking for a place to pupate? I do have wrens so do not want to keep the caterpillars out for them to eat!! Yes, it is nature’s way but we have altered nature so much negatively that I feel helping the butterflies out is not “cheating”. Your photos are stunning-

  26. Kerry See says

    Hi Carol. I discovered two caterpillars on my parsley today (October 12, 2013). Will they be ok to winter over if I leave them outside? I was about to harvest my herbs today but chose to let them be as these two will need food and shelter. Will they form their chrysali on the parsley plant? I have an anise growing not far away. I guess I should leave that in ground as well? Should I wait til they form their chrysali before I harvest my surrounding herbs? Should I net them? The only predator I am aware of in my gardens are skunks.

  27. Mihoko says

    Hi. We have found black swallowtail caterpillar about a couple of weeks ago on our indoor parsley plant. We have been watching how he grow, but he eaten up all the host plant and got out of the pot, started wondering around our kitchen wall, I decided to put him in the big glass jar with store bought parsley, only thing available for us at that point, then he started looking not so good.

    I have 2 girls who are very excited about watching him grow up to be butterfly, and surprisingly enough I found myself very attached to this very cute creature, I am very worry.

    He had some store bought parsley, and started climbing up the stick that I placed in and tucked his head in. Just like the picture above. I was very excited thinking he was going to be chrysalis.
    But when I woke up this morning, I found him still on the stick, but completely upside down and not moving very much. His color is sort of dull.
    I placed parsley near him hoping he will munch again, but so far, he is not moving very much.

    I am concerned that the store bought parsley had pesticides on although I washed thoroughly.
    I also found big poop right before he looked like he was going to be chrysalis, but it was very watery.

    I came across your very inspiring blog while I was searching to learn about our caterpillar.
    I know this article was written while ago, but I do not have any other place to ask questions like this.

    I am very worried. I hope he is ok.

    • says

      Oh, Mihoko,

      I am sorry I did not see this post before now. Your caterpillar sounded like it was doing exactly what it is suppose to be doing. They will pass a hugh poop right before they reveal their chrysalis. They will get in a head down position too temporarily as they need to make a silk attachment to help secure them to the branch or whatever they choose to pupate on. I hope your little guy made it and that you were able to experience the emergence of the butterfly.
      Carol Duke recently posted..Beauties of the Night ~ Luna Moth

  28. says

    I’ve been following the progress of two Eastern Black Swallowtail caterpillars on our parsley plant. Two days ago they disappeared. At first I thought of predators, but I read on another website that the adult caterpillar might leave the host plant and go into the garden and attach itself to other foliage, or even to a fence, foundation, etc. It was disappointing for I thought I could follow the progress right through chrysalis into new butterflies!

    • says

      John, A caterpillar will almost always leave its host plant to find a safe place to pupate. Some will crawl a good distance. Hopefully yours made it without a birds catching sight of it first. In order to see the metamorphosis you would have to bring the caterpillar in or cover the area with a mesh netting. Maybe next time. Good luck and thank you for sharing your experience.
      Carol Duke recently posted..Beauties of the Night ~ Luna Moth

  29. Yvonne Jack says

    I have a dill plant in a container on my front porch that now has nine black swallowtail catipillars on it. They are all about 1.5″ long. The plant is close to being stripped and I am concerned for them. Is there anything I can do to help them without disturbing their life cycle. Should I see if I can purchase already mature plants or just leave them alone?

  30. Judy says

    LOVE this site! Found it when googling info about black swallowtail caterpillars. I get them every year on my parsley, however, this year I have dozens of them on scrappy volunteer dill plants. I’ve relocated some of them to other dill plants cause it seems the bigger ones are picking on the littler ones as they compete for food. As the dill is becoming less available, can I relocate some to the parsley?

    • says

      Hi Judy. Thank you. Yes, you can relocate them to parsley or queen anne’s lace or fennel. If you have the misfortune to have Aegopodium podagraria or Bishop’s Weed, they will eat that too. They will eat anything in the carrot family or Apiaceae. They may become snacks for birds. Good luck!
      Carol Duke recently posted..Beauties of the Night ~ Luna Moth

  31. Kay Jantzi says

    I have loved your site and your beautiful photography! I’ve just become interested in this amazing metamorphosis and transformation from egg to Monarch. I’ve had a couple of successes but it’s not as easy as it looks to raise them. I’d love to find a Black Swallowtail and even though they are in our area I haven’t seen many in my back garden. I do have lots of Wild Carrot though, and have kept it because of it’s lacy design and photogenic properties for my photography. I had no idea that Black Swallowtails would use these gorgeous plants as a host plant for laying eggs, but it makes sense, since I know they like the carrot family! I will be checking out my Queen Anne’s Lace very carefully!

    Thank you for your amazing web site of information.

  32. Lisa Dace says

    Thank you for your post about the instals of the Black Swallowtail. My 4 and 5 year old found these in our carrots and parsley this year and your site and pictures were a great and lovely resource for us. They are taking pictures to school tomorrow and using this experience for their weekly presentation. Thank you!

  33. Mary Holzer says

    Hi . . . My granddaughters and I have just found 5 black swallowtail caterpillars on my fennel plants. Three are big and green, two are little and black with a white spot. What should I do? Looking back through your earlier responses, it looks like they might be snacks for birds if I don’t get them undercover somehow.

    If I put them in something they will have to be fed – what do they eat? Looking at your site, it seems the green ones might be close to forming the chrysalis, but the little ones are clearly not.


    Thanks! Mary

  34. Mary Holzer says

    We figured out a solution – built a cage of wire fencing and net around three fennel plants in a pot and moved the caterpillars into the cage. Took photos and will keep you posted on how it goes. Keep your fingers crossed.


    • Katey says

      Hi, I found some black swallowtail cats on our herbs outside. The first group I believe was eaten by something so the second group I gathered to raise in a container. They’ve done well (I’ve released each butterfly), but one just emerged that I’m concerned about. The weather has been in the 70’s but we just got a cold snap today (figures, the day he emerges). It’s now a high of low 50’s with a low in mid 30’s at night today and for the next week. I haven’t released him yet because I’m unsure if he will be ok. Next week will be better weather…and now I’m concerned about what the remaining two will do. Since they are outside, will they choose to hibernate, you think? Any feedback is appreciated!


      • says

        Katey, I am not sure where you live? Here in the Northeast, the Black Swallowtails are sleeping in chrysalis form for the winter months. We do have butterflies that overwinter as butterflies — Mourning Cloaks for one. Since butterflies are emerging in November I am assuming your are somewhere warmer. In my experience it is always better to release a butterfly as soon as possible once they are able to fly. They will most likely fine a place to be warm. And if not, at least they were able to fly like a butterfly.
        Carol Duke recently posted..Beauties of the Night ~ Cecropia Moth

      • says

        Hi Carol – yes we have eight chrysalises. They attached themselves to the wire frame, so I was able to clean out the center of the cage. We live in Palo Alto, CA, where we do get some cold winter weather, but nothing like the east coast. How long do the swallowtails stay in the chrysalis state? I wonder if the time is shorter if the winters are warmer.


  35. Rita says

    This morning, I found two black speckled larva feeding on my young dill plants I have in a container in my backyard. One large one and one small one. I had never seen these larva before so I went online to identify them and found your website. So glad I did! I live in So California and am so happy when I see the Swallowtail butterflies as I did in my youth. Like I said, I had never seen the larva before, so I put them in a jar to take to the nursery – if I could not identify them online. Needless to say, after finding your wonderful website and Identifying these little guys, I quickly marched back outside and put them back on the dill plants! I just checked on them and they are munching away, like they didn’t miss a beat! I do hope the mocking birds – or other birds – do not get them! Thank you for such a wonderful site!


  1. […] Raising Eastern Black Swallowtail Caterpillars “This year as I eyed an Eastern Black Swallowtail fasten an egg to a tiny Queen Anne’s Lace plant  hidden within some horrid Bishop’s Weed I thought I might like to get to know the offspring of this butterfly too.” by Carol Duke […]

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