Image of mama wasp with mudball

The Surprising Life of a Gentle Mud Dauber Wasp

The mother asks for nothing but a little clay and a few spiders. The father protects the kids and helps sculpt the nest. Neither has any interest in stinging people. What could be more fun than watching these dedicated parents and natural architects?
mama carrying mudball
A mama organ pipe mud dauber wasp lifts off from her quarry, a muddy patch near our pond, to carry a clay ball back to her nesting site.

Where are all the butterflies? What happened to the summer rains? As drought looms over us like a wilted cloud and the butterfly season feels vaguely doomed, it’s probably natural that we tend to notice only what’s missing. But look a little closer and listen carefully, and life makes itself known in the cracks and crevices, under the logs and leaves, and—most recently in our habitat—even in the mud.

Last week, instead of packing masks and hand sanitizer for our annual trip to the beach, my husband and I chose a safer vacation spot: a bench by our new pond. Though I craved the sand between my toes and the salty air in my nose, the tiny oasis offered something else: unprecedented frog-watching opportunities, dragonfly sightings, a face-to-face encounter with a scarlet tanager, and conversations with my favorite chipmunk as he wove in and out of the stones.

And while I longed to hear the sea cradling the shoreline, if I’d been away from home, I would have missed out on a new sound: an intense drilling at the pond’s edge. At first it reminded me of buzz pollination, which occurs when native bees contract their flight muscles and vibrate them at a high frequency to dislodge pollen from flowers. But a closer look revealed that these sounds of industry were coming from a different kind of animal, one of nature’s most diminutive architects:

She was an organ pipe mud dauber wasp, and when I hit the books to learn more about her, I realized my mental comparison to buzz pollination was no coincidence. The wasp was using a similar mechanism to mine the soil: “Mud daubers become musical masons as they work the mud from which they build their nests,” writes author and biologist Justin Schmidt in The Sting of the Wild. “The ‘musical noise’ … is generated by contracting the wasp’s thoracic flight muscles, thereby vibrating the head and mandibles while emitting a high-pitched sound.”

After forming a mudball, the subject of my fascination zoomed off with her building materials, returning a few minutes later for more. When Will came to join me on the bench, he was just as mesmerized by the invertebrate excavator and began taking pictures too. “Do you think she’s building a nest under the deck?” he wondered aloud. “I’ll go take a look!”

Only a few moments passed before Will’s triumphant return to the pond. Sure enough, he reported, our little friend was making a nest right in full view. It was an activity we’d end up watching off and on for days:

For as long as I can remember, organ pipe mud dauber wasp nests have graced the deck beams above the entrance to our basement. But though I’ve taken plenty of pictures in the hopes of changing people’s minds about these unassuming creatures, I’d never witnessed the nest-building process. As the mother creates cells for eggs within the tube, she also catches and paralyzes spiders, stuffing them into each cell so her wasp babies will have something to eat when they hatch.

Watching her stretch the mud balls out, elongating her organ pipe nest a little more with each trip back from the pond, I admired the hard-working mama’s artistry. I also started to notice something else: the head of another wasp peeking out of the tube, sometimes quickly retreating and sometimes chasing away other wasps. Mud dauber wasps are solitary—one of the reasons they’re gentle around people, since they don’t have colonies to defend. So who, I wondered, was the second wasp hanging around the nest?

Through further reading, I Iearned that male organ pipe mud dauber wasps are dedicated dads. They stay in the nest to guard the larvae while the mom collects building materials. Sometimes males even help with construction, but their main role is protection from numerous threats: Without their vigilance, other mud dauber wasps might try to claim the nest as their own. Predators and parasites, including flies and other wasp species, are also among the dangers.

It wasn’t always possible for me to tell who was coming and going, and sometimes it seemed there might be a second female or male trying to commandeer the hard work of the original parents. But one kind of interloper was unmistakable: cuckoo wasps looking to parasitize the organ pipe nests by laying their own eggs in them.

They weren’t succeeding, at least not while I watched. But if they do eventually manage to sneak in, their cuckoo wasp babies will hatch and devour at least some of the contents of the nest. Depending on the species of cuckoo wasp, they might eat the spidery snacks, thus starving the mud dauber larvae, or they might eat the mud dauber wasp larvae directly, or both.

This may not seem like a neighborly way to raise a family, but I couldn’t help feeling sorry for the cuckoo wasps anyway; it must be difficult to have to engage in such covert operations just to find a home for your young. I couldn’t ponder the odd behaviors wrought by evolution for long, though. Soon enough, another kind of wasp came into view, and this one was carrying a heavy load, a hapless spider destined to become a meal:

My heart went out to the little spider even as I reasoned that wasps need to eat too. Once again, the insects had no time for such sentiments. During the brief moment when I’d turned away to record the spider’s sad demise, one of his behemoth cousins came to level the playing field, parking herself right underneath the mud dauber wasp nest. image of Spider near mud dauber wasp nest

She stayed still for a long time, and if she eventually caught her quarry, I wasn’t around to see it. I suspect our wasp family survived her presence, though. Just a few days later, the wasps have laid down a second pipe, indicating they are still hard at work on providing for the next generation:

Image of Organ pipe mud dauber wasp nests under deck
A few inches to the right of the third crossbeam, on the wood right next to the house, the new parents made a second organ pipe over the past few days. We’ve coexisted peacefully with these nests under the deck for 20 years.

Though we won’t experience the splendor of the high seas or low tides this year, there is high drama in low places right here at home, as we watch many kinds of animals feeding, teaching and fighting to protect their young. I’m happy to see the butterflies slowly trickling in above us on their way to the wildflowers now, and I was delighted to welcome the monarch who landed on my shoulder today. But I’ll also continue to appreciate what’s happening at our feet, keeping the soil by the pond moistened not just for puddling butterflies but for all the mother wasps who need little more than mud and water to craft a safe home.

Image of the ghost of organ pipes past
Ghosts of mud daubers past decorate some of the beams under the deck. We did not remove the nests, but perhaps a bird or other animal did.
Links to Further Info:

“Pipe Organ Mud Dauber, Trypoxylon politum, Found in Colorado,” Bug Eric by Eric Eaton

“Organ Pipe Mud Dauber (Family Crabonidae),” The BugLady, University of Wisconsin

Organ Pipe Mud Daubers, Hilton Pond

Cuckoo Wasps, taxonomy and life history, Discover Life

“Who’s Cuckoo – Cuckoo Wasps, Chrysididae,” Bug of the Week by Mike Raupp

“The Cuckoo Wasp, A Gorgeous Parasite,” Bay Nature Journal

27 thoughts on “The Surprising Life of a Gentle Mud Dauber Wasp”

  1. Thanks for this information. I’ve seen a similar looking wasp dragging a large spider and was wondering what was going on. I haven’t seen any nests yet maybe they have a good hiding spot.

    1. Hi Katrina! It could be that you saw a wasp that has a nest in the ground. The one in this post who was dragging the spider wasn’t one of the mud daubers — she had some orange in her — and she seemed to be going somewhere on the ground, so maybe a burrow there. I haven’t actually seen one of the mud daubers carrying a spider into the organ pipes yet. Probably I should just sit there for a few hours and wait, and I might see one.

  2. You capture the most interesting videos! Thanks. And I’m glad to know mud dauber wasps are not dangerous.

  3. Fantastic post❤️ Last August I found “organ pipes” on my garage wall. A few minutes on line, I learned about who made these magnificent structures. What an honor to be chosen by these delightful wasps! We never even observed their construction despite my car just a few feet away. I also had to laugh when you described feeling sorry for the cuckoo wasp and the little spider. I do the same thing. Thanks for showing what really matters in these dark times.

    1. Hi Joann, thanks so much! Isn’t it amazing how these nests just sort of seem to show up? I don’t know why I had never seen the process in years past — maybe I just walked by too quickly, or maybe I wasn’t around during the day and weeks they were building them. I’m glad to know you have the same tendencies toward empathizing with the all the creatures caught up in the drama, too. It’s hard not to admire their persistence and work ethics!

  4. Nancy,
    I just love all your posts and garden adventures, but this post was one of the best! It was so interesting and dramatic ( nest defending!). I’ve lived with mud daubers all my life and have always been afraid of them, but now I know they don’t sting and lead a very interesting life. I will never scrape down their nests again.
    I have a wild and wonderful garden too, and love being out in it; but your blog is a real resource. I always learn something interesting that helps me appreciate my yard even more.
    And the pictures are stunning!
    Thank you,
    Stephanie

    1. Hi Stephanie, thank you so much! Hearing that you won’t scrape down a nest again is the best type of feedback I could get, since my hope in writing these things is that people will be able to see these little creatures differently. I really appreciate your reading this and my other posts as well. Thanks for taking the time to let me know and for all that you’re doing in your habitat too! <3

  5. It’s an interesting coincidence you mentioned this. Only a day or two before this post came out, I accidentally crushed a mud dauber nest. It isn’t the same kind of wasp, but similar. My trailer door is open a lot of the time to let my kitties go in and out, but wasps are coming in. I gave up on trying to chase them away. They never tried to sting me, and they were alone, so it wasn’t like I had 200 yellowjackets making a nest inside my house.

    It made a nest up in a terrible place, the metal thing that a sliding door hangs on, which is sort of like a tunnel above the door. The door got bumped and was knocked partway off the hinges, and it crushed the nest. All these fat little things with legs fell out, and I was like, “Eww… are those *spiders*?” I didn’t understand what it was, and I thought, “Maybe the baby wasp larvae look like spiders.” There was also a white wormlike thing in there, too. Maybw that was the larva. Ill have to look for a photo of a wasp larva now. But this post answered my question, yes, those are spiders!

    1. Hi Nicole, that’s so interesting that you were able to see inside! What good timing. I think the Hilton Pond link at the end of this article shows pics of the larvae. They took apart a nest to see what was inside.

  6. Nancy, I read this entry this morning and while watering my garden, saw a wasp do exactly what you described and fly up into a tree with her little ball of mud! Thanks for the description of what I understood immediately! Question…yesterday I found a fascinating, beautiful, black-and-white insect in my garden that turns out to be a bald-faced hornet. I only saw the one, and it was back in my “wild” area corner. I will alert the neighbors (four yards meet there) and be on the lookout for the nest, hopefully just monitor it and stay a safe distance away. But my dog often chases chipmunks back into that area, and neighbor children often visit my garden and I’d hate for anyone to be stung. Any advice? Thanks (in Wilmette, IL).

    1. Follow-up…after posting my question, I did a search on baldfaced hornets on your web site thinking “maybe she’s written about them before” and found your 2015 article on exactly that subject! https://www.humanegardener.com/happy-as-a-hornet/ I am curious whether you’ve had additional experiences with them since then? I was wondering how close one could get to the nest without disturbing them…you suggest 6 ft. I can put up a temporary fence to remind us all not to go back in that corner.

      1. Hi Martha! I think your temporary fence reminder should help a lot. My experience with baldfaced hornets has been that you have to get pretty darn close for them to start worrying about you. I really got within like a couple of feet when they got upset with me. If you know where the nest is or at least the general area where it is, it’s so easy to avoid. The trouble comes for people when they are completely surprised by it — like if they reach their hand in a shrub or something. Hope that helps. 🙂

  7. Amazing. I love learning about Nature’s littlest engineers, from.bees and spiders to termites and ants. There’s a whole world of construction and creativity that goes on almost right under our noses, if we simply take the time to notice and appreciate it.
    Thanks for sharing this fascinating aspect of it!

    1. Hi Dave! Yes, it’s so amazing! What really strikes me every time is that often I’m just sitting there in my own obliviousness, thinking about something completely different, not really realizing that all these things are going on right in front of me. And then something just happens to catch my eye or reach my ear that looks slightly different. It’s never when I’m actually looking to find something …

    1. Hi Jason! Haha, it’s actually very quiet, though – you have to get super-close to hear it, or it has to just happen to be a really quiet day. I had read they make this sound while building nests, too, and I didn’t realize it until recently I was standing near them at the potting bench. If I hadn’t already known about them, I may have found it a bit disconcerting/worriesome!

  8. Hi Nancy,
    I’ve been fascinated by mud dauber wasps for as long as I can remember. Their solitary ways, unique shape, crazy movements, and those organ pipe mud nests seemed almost magical when I was young. And, we didn’t need to be scared of them!
    I think your article is wonderful, not just for adding to our knowledge about these insects, but also for reminding us that there are amazing creatures all around us that deserve our interest and respect, if we just take a moment to stop and observe.

    1. Hi Mike, thanks so much! I’m so happy you read it and it resonated with you and your experiences. It sounds like you’ve been a wasp watcher for a very long time. That is awesome. 🙂

  9. thanks for these videos. I see mud daubers on one of my shallow bird baths almost every time I pass by. I look for their nest but have yet to find one. – ps. I am reading your book ( from library) and about half way through. I am so impressed with it I just ordered my own copy. – Barb in Ontario Canada

    1. Hi Barb – I’m sorry I missed your comment before! It’s so fun that you have a regular watering station for them. Thank you for reading my book and for your kind comments! 🙂

  10. Thank you for sharing this! My family has been fascinated by beautiful blue mud daubers that live near our house for years. Sadly, this is the first time in 6 years that they haven’t returned. We sure miss them!

  11. I found a mud nest on a rock that is decorated on the outside with tiny black and white pebbles.
    They create a mosaic pattern. The pebbles are not present throughout the mud used for the nest that measures about 1 and 1/2 ” X 1″. There exit hole is about 1/4 “. The tiny pebbles were added to the mud nest to create what looks like art to me!

  12. Hi Nancy!

    I have had the tremendous joy of watching a mud dauber family build their nest right up against my sliding glass door! Now I’m not usually a bug person, but after seeing this interesting bug flying around, I got to researching and found out about mud daubers. My boyfriend and I watch the little wasp family everyday and it’s truly incredible watching the females build the nest and the males protecting it! Plus the nest is right up against our sliding glass door, so we get front row seats to watch every detail. We even named the family! Thank you so much for your article! It definitely feels better knowing that I’m not the only one who finds the beauty in watching these bugs exist!

    1. Hi Sydney! My website crashed around the time that you posted this comment, and I had to have a backup reinstalled — which erased comments that had been sent in the interim. But they come to my in box as well, so I was able to repost it here. Anyway, I was delighted to read about your observations and the window you are getting into the mud daubers’ lives! How cool is that? I bet you are becoming more and more of a bug person by the minute. 🙂 It’s amazing to see how hard they work to survive and ensure the next generation has what it needs, isn’t it?

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