Like Mother, Like Daughter

No, I'm not trying to steal someone else's blog title (although I do enjoy visiting). It's just that Rebecca seems to be having loads of fun with caterpillars lately. :-)

Check out this grin:A close up. This hairy customer has been chowing on our spearmint. We're planning to set it up in a jar. If it's a moth, it will spin a cocoon--something most of my children haven't seen yet.Can you stand another Eastern Black Swallowtail photo? I've been capturing them younger and younger. It's hard to imagine I'll ever find one smaller than this, though.Once again, that's my pinky!

Crazy for Caterpillars

Okay, perhaps I am obsessed! We didn't have caterpillars last year, so I am enjoying and nurturing this "crop" all the more.

Check out these little guys: Another picture trying to show perspective. That is my pinky fingernail.

You know how birders keep a "life list" of all the species they have seen? There are only a few moments of the Eastern Black Swallowtail's life cycle that I have been waiting to catch. This week I found one--an egg!It fits the description--round and creamy white. I thought it was supposed to be under the leaf, but this spot where the leaflets join must be almost as good.Under the stereoscope we could see the flatter area where the egg was glued to the leaf.

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I brought it inside, hoping to find a baby caterpillar later to prove this egg is what I think it is. So far, nothing has hatched. I do have confirmation from another quarter, though:Yes, that's a larva next to a mostly eaten leaflet with a lighter egg on it. When we looked at this egg at 40x, we could see the hole made when the caterpillar emerged. The egg is a lighter color because it is empty.The final moment I've been hoping to catch is the butterfly actually emerging from its chrysalis. We've come very close, but not close enough. Maybe this spring . . .

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And now I've thought of one more thing (isn't there always one more thing?) to add to my wish list. It would be amazing to watch a butterfly lay her egg. I have no illusions of accomplishing that, however.

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Have a great weekend. Go outside!

Sufficient Indeed

I've been worried that my parsley crop was not lush enough this year to entice a female Eastern Black Swallowtail to lay her eggs here. On Monday I found one small caterpillar in the back garden. Hurrah! I set up a jar with the traditional climbing stick, food, and stocking cover.

I checked again on Tuesday (yesterday) and found another specimen. Next I inspected the parsley by the front door and discovered the four tweensiest caterpillars I've ever seen!

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I took some close-up photos, but the perspective was off--the creatures didn't look all that small. Here's a picture from this morning showing small and weensy (See it on the stem to the left?) caterpillars together.

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The tinies were hard to find (Yesterday when they were on leaves I needed my glasses just to be sure they weren't actually dirt!) partly because they're short, but mostly due to their incredible skinniness, which will not last long. These guys are eating (and waste producing) machines.For detailed stories of our favorite caterpillars, see my previous posts here. (They're in reverse chronological order.)

Too Little, Too Late?

Parsley is one of our doorstep herbs. I grow it for eating, of course, but also as part of our caterpillar tradition.

This year's seeds did not thrive, to put it mildly. (Two separate plantings of basil also flopped. Seedlings from my sister are saving the summer.)

Hoping it's not too late (our caterpillars usually appear in late August or early September), I bought some parsley for replanting.It doesn't look like much yet, but hope springs eternal, right?While working, I noticed that some of our current crop had been . . . cropped.I'm not sure what's been nibbling, so I decided to plant one set of seedlings in the fenced backyard garden. We'll see if those stems are more prosperous.Updated: I just watered both plots, and the backyard group looks healthier today. It may be because I separated those into fewer sections, or maybe the scrawny stems in front didn't get planted deeply enough. Time will tell. Wish me luck!

Caterpillar Planting

Butterflies are beautiful, but caterpillars are amazing! Here's an Eastern black swallowtail: Its range covers most of the U. S. and parts of Canada. The caterpillars primarily eat parsley or the leafy tops of dill and carrots. In our area (northern VA) the eggs hatch in late August or early September, but now is planting time for their food.

In the spring we spread parsley seeds in a patch near the front door. We enjoy several months of herbal harvest until the caterpillars appear. Then we share the greenery, feeding our baby insects in their big jar.With parsley to eat and a stick to climb, they're happy campers.

Eventually they assume "the position", molt the final skin, and appear as chrysalises.We usually overwinter them in the fridge; mature butterflies emerge in the spring.

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If you'd like to grow your own butterflies, try planting some parsley this spring. With some luck, a mama will lay her eggs in the summer and you'll have caterpillars to watch.

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For more details, you can read my butterfly posts here (they're in reverse order, with the oldest at the bottom). Anna Comstock's Handbook of Nature Study has a lesson on Eastern black swallowtails, and Rick Mikula's The Family Butterfly Book is also a useful resource (I borrow it from the library).

Metamorphosis: the Final Chapter

You may remember that we nurtured some Eastern Black Swallowtail caterpillars last fall (click on the "butterflies" label to see those posts). A few weeks after they formed chrysalises, two of the four butterflies emerged. The remaining two entered our indoor winter (the basement fridge) to wait for spring--most EBS's do overwinter in nature.

When warm weather arrived, we took the jar out of the fridge and set it in the kitchen. It usually takes 2-4 weeks for an EBS to emerge. The chrysalises start out bright green , although some turn brown (probably in response to attaching to rough vs. smooth wood). One of ours was still green, while the other had darkened to almost black, usually signifying a dead butterfly.

Well, on Easter Sunday morning, I noticed that the green chrysalis was now semi-transparent! I've seen pictures of Monarch chrysalises going from opaque to see-through, but have never noticed this change in our years of hosting EBS's.

The first two photos below show green chrysalises in the fall. Third is a picture of Easter's chrysalis. Can you see the spots inside?
What an exciting image for Easter! That body, encased as though in a tomb, transformed and reentering the world.

Every now and then the chrysalis would move, jerking from side to side. Len managed to catch some of the action on camera. The frame wiggles a bit (he was holding the stick in one hand and the camera in the other), but it's still very cool:

We didn't want to miss the butterfly's entrance and so took the jar in the car on our way to the bluebells. As we drove home it emerged, although even Marianna (who had the jar on her lap) missed the actual moment!

The butterfly's wings were wrinkled. It took a while to pump them up with fluid and get ready to fly; at one point it fell to the bottom of the jar. I "rescued" it using a trick learned from a book: I offered it the bristles of a soft paintbrush as a way back to the branch.

Here's a picture of the butterfly readying its wings. Notice the spots on its body and then look again (below) at the transparent chrysalis. Wow! Updated to add: Yes, the blackened chrysalis held a dead butterfly (we opened it). It had darkened in the fall (at about the same time the other two completed their cycles), so we weren't surprised to see a dried out body this week.

Caterpillar Diaries: Day 29

I'm confused, and I think our Eastern Black Swallowtails are, too.

We've never had butterflies emerge so late in the season. After the four chrysalises formed, I kept the jar on the school table for a few days. Then Marianna noticed that one was getting darker. Not the change from green to brown that they sometimes make, but the darkening that in the past has foretold the rotting of a "dud".

That was my signal to put the jar in the fridge to prevent any others from going bad. A few days later I had to take the jar out again to make room for groceries, but I left it in the basement, which is at least cooler than the main level.

After a few more days--eek!--I saw a butterfly in there as I passed by! It had emerged from the first (darkened) chrysalis, I think 14-15 days after forming.

I put the jar outside in the shade to let nature decide what to do with these guys. We've had some cool nights, but also some really warm days, so there may be some confusion about overwintering vs. emerging NOW.

Another butterfly has emerged since then, and a third chrysalis is darkening. The jar is staying outside for now. If we have any chrysalises left when winter truly arrives, I'll need to decide about leaving them out vs. putting them in the fridge. Butterfly #2 waiting to be released. Can you see the empty chrysalises on the stick and the wall?

It was still subdued and crawled from hand to hand rather than flying away immediately, so we must have found it not long after its emergence.

Joe coaxed it onto a flower in Marianna's cutting garden. We also have a butterfly bush nearby.

This second EBS was released on October 13 (caterpillar day 33). I'm not too optimistic about its survival and reproductive chances, but I suppose this is what would have happened if it had always lived outside, too.

Chrysalises

On days 14-17, our caterpillars crawled up their sticks (with one going up the side of the jar instead) and assumed the "ready position", as I think of it. Each one makes a little silk pad to rest its back end on and also spins two silk strings to hang its top end from. Then it scrunches up (it really does look smaller than before) in the shape of a comma or apostrophe. It hangs there for about 36 hours, occasionally wiggling. See the one farther down the stick? It's in a more classic semi-upright position than the top guy, but I didn't get a good enough picture of that one.

After the allotted time has elapsed, the final molting occurs. The [looks like a caterpillar] wiggles and shakes off the last skin.And from inside that skin appears the chrysalis!It is so much more dramatic than watching the spinning of a cocoon. One moment it's a caterpillar, and the next a chrysalis. Several years ago we actually caught that moment on video, but it's not digital so I can't show you.You can still see the silk strings holding it in place.If you get an early "batch" of caterpillars (say, July), they'll emerge as butterflies in the same season. That happened to some at my sister's house this year. Ours almost always appear later (the final chrysalis formed September 17th), and the chrysalises in real life would overwinter outside with the butterflies emerging in the spring. The Family Butterfly Book states that overwintering species can be kept in the refrigerator and removed about 30 days before it's time for them to emerge. We've had some success with this (and some failure, too).

Caterpillar Anatomy

Swallowtail caterpillars have an organ just behind the head called an osmeterium. When it is bothered, the caterpillar turns a sort of pocket inside out, and these orange "horns" are pushed out and then withdrawn again.

The horns emit a real stink (reminding me of marigolds). Apparently this lets birds know that the caterpillars taste bad. One of our books (Anna Comstock's Handbook of Nature Study has a unit on the Black Swallowtail) states that this protection is why they don't hide under leaves.

I've been trying to get a good photo of this phenomenon, but had no luck until today. Becca found a caterpillar outside in the parsley patch (the one that escaped during cleaning?) and we poked it a bit...for educational purposes, of course.

There was some discussion of bringing this guy into the habitat, but we've got several making chrysalises already (posting tomorrow I hope), so I decided not to be greedy. Besides, it will be fun to see if we can find this one's chrysalis outside in a few days--a real nature hunt.

AKA The Four Little Pigs

Day 11, 10:00 a.m.

Day 12, 10:00 a.m.

Caterpillar Diaries: Days 8-11

On day 8 the smallest caterpillar took a turn for the worse. When I cleaned the habitat I may have disturbed it too much (it really didn't want to leave the side of the jar--maybe it was molting), or maybe it was just not doing well anyway. Part of the time it wandered aimlessly around the jar, but mostly it just lay there. It seemed to be shrinking (these guys normally eat A LOT) and was dead by the next day. I hope it's not my fault.Above is a caterpillar on day 8. Notice how it's not spiky anymore. It's black with yellow spots and thin bands of green. Here's one the next day. Yes, it's grown, but it's not a giant--that's Becca's hand. Notice the three pointy legs near the head; it has 6 real legs. There are 4 sets of puffy prolegs farther back, which it uses for holding on to sticks or parsley stems (or fingers!).This is a day 11 picture. Now the green stripes are becoming more prominent. Soon it will look like a green caterpillar with black stripes. Look at its size next to the parsley leaves and compare to one of the first photos (below). Wow!

Below is a photo of "the guys" in their refreshed habitat this morning. I'll try to get a picture tomorrow to show just how much these four little piggies can eat. I'd really like a movie showing them eating--it reminds me of vertical corn-on-the-cob munching--but it's hard to focus through the jar. (BTW, if you look closely you can see 3 of the 4 in their "jungle". Try clicking on the picture to enlarge it.)

This year we are studying flying creatures in science, so we've jumped ahead several chapters to follow our up close and personal insects. We keep these guys on the school table or island and so observe them throughout the day. Marianna and Joe are also doing some narrating and drawing.

Caterpillar Diaries: Day 5

Here are the caterpillars just before removal for a cleaning (the sticks are already out). All those little black specks are frass. Check out the growth already! Not only is this guy bigger than the other day, notice how its coloring has changed. It's still mostly black, but has yellow dots and is less spiky looking. You may be able to see the thin white stripes around its middle, all that's left of the white band from before. The different growth phases are called instars.

The contrast is even easier to see below, as one caterpillar hasn't changed as much yet.

After we change their parsley, the caterpillars usually have an active time, moving around and eating. On this day there appeared to be some jostling for position, including pushing and shoving ("Hey! You! Get off of my stem!"), although there were plenty of leaves for all.

Caterpillars are insects, so they have an exoskeleton that doesn't grow. As it gets tighter, a new exoskeleton forms and the caterpillar splits open the old one and crawls out of it. This is called molting.

Anyway, today Marianna saw a crumbled black blob just a few times bigger that a dropping. We suspected it was a discarded "skin" and looked at it under 40X magnification. I wish we could have taken a picture for you--it was so cool! You could see that it was opened (there was an inside and outside, although it was crumpled up), and could see lots of the little black spikes that the smallest caterpillars have.

Caterpillar Diaries: Day 3

These are the caterpillars on Day 3 (Saturday, September 13). They've grown a bit compared to the first picture, but still have the same coloring. Here's some wilting parsley. We remove the sticks, parsley, and caterpillars from the habitat for cleaning, usually every day. Cleaning consists of tapping out the droppings (called "frass"), then putting the sticks back in with fresh parsley and our charges.