Day 34: They Grow Up So Fast

Remember that large collection of butterfly eggs that I found almost 2 weeks ago? They’ve been eating, pooping, and growing non-stop ever since.

For some reason it seems that some grow faster than others. I generally keep the very little ones in a small plastic container with their food, as it helps to keep them from wandering off. But once they get big enough (third instar if we’re being technical), I transfer them to a larger mesh enclosure where I can provide more food, and where they can eventually pupate.

About half of the growing caterpillars outpaced their siblings, and so I transferred them to the larger enclosure first. The rest went into a second enclosure a few days later. Now that first group has grown to the point where they are ready to pupate.

When they’re ready, they stop eating, purge any undigested food from their stomachs, and search for a place to attach themselves to transition to a chrysalis. In the wild they can travel pretty far – when I used to let them grow outdoors, I’ve found their chrysalises attached to plants over 25 feet away. To get to those plants they would have had to crawl down the pot they were in, up a two-foot tall stone wall, and then across the garden to the plant.

Being in an enclosure limits their ability to find an attachment site. Sometimes they climb the enclosure itself and attach to either the sides or the top (as Lazarus did), but that’s not ideal, as it makes it hard for me to attend to the others without disturbing them. So I create what I call a Pupation Station.

The new Pupation Station

They are pretty simple: I find a branch with a Y-shape to provide a stable base, cut sections of branch at a slight angle, and then glue them to the base. Most of the time the wandering caterpillars find it, and choose to transition there. Here is a photo from last year’s crop of caterpillars, where 5 of them attached themselves to the branches:

5 Swallowtail chrysalises

So as I mentioned, the first group has already begun the pupation process. Two of them have purged, and have attached themselves to the ceiling of the enclosure. The rest are looking pretty pudgy, and I suspect that they will soon join them.

2- week-old big fat caterpillars

I took the above photo during a feeding/cleaning session. I remove the bundle of parsley and/or rue from the container of water, and separate the stalks with caterpillars from the rest, which is discarded. I take a bunch of fresh parsley, add the stalks with the caterpillars to it, and tie the base with a rubber band. Meanwhile I empty the glass that holds the water, as it is pretty gross from all the caterpillar poop that drops into it. I’ve started adding some round glass pieces to help prevent the caterpillars from drowning, so those have to be washed too. Then everything is carefully re-assembled and placed back into the enclosure.

Speaking of not drowning, I noticed this morning in the enclosure for the slower-growing caterpillars that one of them was partly submerged.

Saved by the glass pieces!

It looks like it had fallen down from the parsley leaves into the water, but since the glass pieces are there, it was able to crawl back up the stems to continue feeding. It made me very happy to know that I had learned from the bad experience of the past, and that adding those pieces saved a caterpillar from drowning.

Day 32: Caterpillar Update

Last week I wrote about the experience of finding over 30 caterpillar eggs at once, when typically I only find a few. So I thought I’d post an update on how they are doing.

A few days old

As far as I can tell, all of the eggs hatched. It’s hard to say for sure because in the two days after the initial finding, I found 5 more eggs, and then shortly after that, two baby caterpillars, like the ones in the photo above. So honestly I’ve lost count. Suffice to say that there are many, many caterpillars crawling around and eating like crazy!

Second Instar caterpillar among its smaller siblings.

When they’re this small, they are mostly black with a band of white around their middle. This is actually a form of camouflage, as it makes them look a bit like bird poop. Yes, bird poop mimicry is actually a thing! They keep eating and growing until they need to shed their skin to get larger. They look a little different in this next phase, or instar, besides the obvious part of being bigger.

I keep them in a plastic container until they reach the third instar, at which point I move them to a bigger enclosure where I can provide more food for them. It’s important to keep them contained, because they do like to wander!

Last night I moved a lot of them to the larger container, but there were a few that had wandered away from the food, and were just hanging out motionless. Usually if you place a bit of food in front of them, they crawl on top and start eating, but not these caterpillars – they weren’t interested.

In the morning, though, I checked in on these stragglers, and saw this:

Leaving the old skin behind

The dark, crumpled-up bit on the left is the old skin from its previous instar. The new, much bigger third instar caterpillar emerged by attaching the back section of its body to the surface with some silk, splitting the skin at the head, and then crawling forward, leaving the old skin behind. A short while later it definitely was interested in the sprig of parsley I placed in front of it, so once it was aboard, I transferred that sprig and its passenger to the larger enclosure. There they’ll continue to eat and poop for a few days, until an internal trigger tells them it’s time to move on…

Day 28: The Impossible Butterfly

I wrote this last Saturday evening right after it happened, and posted it to Twitter. I had plans for writing something different today, but our cat had other plans, and became ill. So I’ve just spent most of the day in the “waiting room” (sitting in the car until called), and then having the cat treated. It’s odd how doing almost nothing all day long can exhaust you!

So rather than write something brand-new, I thought I’d re-post my incredible experience. If you’ve followed this blog, you’d know that I raise caterpillars of the Easter Black Swallowtail butterfly, from here, here, here, and here.

I’m at a complete loss for words. I just experienced something I didn’t think was possible.

Earlier today a butterfly emerged from one of the pupas in my nursery. He had a wing deformity (yes, it was a male), and when he attempted to fly, he couldn’t get more than a few feet before returning to the ground

Resigned that he wasn’t going to survive, I placed him on a flowering plant in the yard, and assumed that nature would take its course, and the butterfly would soon die.

I kept returning every hour or so throughout the evening to check on him, and he hadn’t moved very far on the plant. As the evening grew late, I wanted to say my goodbyes. I know it seems silly, but raising these marvelous creatures from egg to adult creates an attachment. I placed my fingers in front of him, and he instinctively climbed up onto my hand. I spoke to him, telling him how sorry I was that his wing was deformed, so he wasn’t going to be able to fly and live his life.

After a minute or so, he started flapping his wings, and flew for a few feet, as he had done before, but quickly landed on the ground. I again placed my hand in front of him, and again he climbed aboard. I talked to him a little bit more, and again he started to flap his wings. This time, though, he flew!

I watched him fly across the yard, up over the garage, and then over the back fence. He quickly disappeared into the distance, and I couldn’t see him any longer.

I don’t know what kind of life he will have, but to be able to fly away on his own is something I truly never thought he would be capable of. I am still feeling that warm giddiness at witnessing what I had thought was impossible.

Day 22: The New Brood

If you’ve been reading this blog, you know that I raise caterpillars. How do you find caterpillars to raise, though? The best way to grow the types of plants that the species of butterfly you are interested in likes to lay her eggs.

For the Eastern Black Swallowtail, which is what I primarily like to raise, the plants include parsley, rue, dill, carrot, fennel, and a few others.

Part of my daily routine during the summer is to check these plants for eggs. They’re tiny and hard to see, but when you know what to look for it makes it easier. I found the group of 3 eggs that Lazarus came from a few weeks ago, which was a bit early in the season. Since then, nothing.

Until last Friday.

29 (count ’em) swallowtail eggs

I began inspecting one of the rue plants, and immediately saw an egg. So I grabbed a scissors and a small container. This way I could trim the part of the leaf with the egg, and save it in the container. I collected that egg, and began checking out the rest of the plant. There’s another one! And another! It seemed that everywhere I looked I found another egg!

After I was sure I got all the eggs from the rue, I moved on to the parsley plants. Sure enough, there were several more on those plants, too. It took some time, but I was finally sure that I had found them all. Back indoors I very carefully arranged the various plant clippings so that the eggs were visible, and took the photo above. Prior to this, the most eggs I had ever found was 6, so finding 29 at once was incredible! Over the next 2 days I found 5 more, bringing the grand total to 34. I’m going to need a bigger housing for them!

Someone asked me why I bring them indoors, where the temperature is much cooler than they would be exposed to outside. There are several reasons, but the primary reason is that it shields them from predators. I did some research online first to make sure that it wouldn’t be harmful to be indoors, and there does not seem to be any problems with it. The results I’ve gotten have borne that out.

Freshly-hatched caterpillars!

This morning the eggs began hatching. As soon as they hatch they start eating the leaf they are on, which is pretty wilted by now, so I add fresh host plant material for them to munch on. Can you find all the caterpillars in the photo above? I can see at least part of 14 caterpillars. There are also 2 unhatched eggs visible, and if you look at them closely, you can see that they are no longer the smooth yellow color of the newly-laid eggs.

Those stripes are the segments of the soon-to-be-hatched caterpillar. I imagine that these are from the 5 eggs that I found after the first batch, as they seem to be a day or two behind in development.

This will certainly be a good test of my caterpillar-raising skills in trying to help 34 different creatures grow to adulthood. I’ll be sure to post about any significant events in that process in the weeks to come.

Day 20: Lazarus Update

A couple of days ago I wrote about our miracle caterpillar, which we named Lazarus, due to its ability to come back from the dead. I don’t have much on my mind that I want to write about today, so I thought I’d give you an update.


Lazarus continued eating and pooping, as caterpillars do. Yesterday, though, it reached the transition point in its lifecycle, where it stops being a caterpillar and becomes an adult butterfly. What the caterpillar will do at that point is stop eating, and because it will no longer be able to digest, it “purges” – it vomits up the contents of its digestive system. In the photo above you can see the circular stain with a dark center mass. Well, you can sort of see it; I keep the caterpillars in a collapsible laundry hamper with nylon mesh sides that allow you to see through somewhat, and that makes the image a little unclear.

Once they’ve purged, they begin to wander in search of a place to attach themselves. I created something for them to use, and most of the caterpillars end up pupating on it.

Caterpillar housing

You can see it in the center – it’s just a few sticks glued together. Again, due to the nylon mesh it’s difficult to see clearly, so here’s a photo I took last summer at the peak of pupa season:

Five pupas

So yeah, the caterpillars seem to like this arrangement. But not Lazarus! If you look closely at the top left of the photo of the caterpillar housing, you’ll notice something:

Lazarus wandered all over the enclosure, and then decided to attach to the top panel! It still hasn’t pupated, but I expect that to happen later today. I’ll update this post with an image of that when it happens.


Two hours later, and Lazarus has shed his caterpillar skin, and become a bona-fide pupa! Now the long wait until the beautiful butterfly emerges.