Category: Caterpillars

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.

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:

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.

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.

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.

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.

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!

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:

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…

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.

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:

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.

UPDATE:

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.