More travel!

I know, I haven’t even finished my stories about the Texas trip, and now I’ve gone to Colorado for more moth and caterpillar wrangling! All the pictures and stories will keep me busy for a while. Recently got home after a week of beautiful mountain views,  black lighting, caterpillar hunting, rainstorms, great people, visiting collections, and spending time with my aunt (who lives in Boulder) as an added bonus. My mom accompanied me for part of the trip, and was a great sport about helping me find collecting locations.

I started by flying into Denver late Thursday night (a trip fraught with nearly missing flights, booking the wrong hotel, and a long but interesting cab ride). I met up with my advisor in the morning and we hashed out our plans. Nearly everything had to be improvised due to the weather and who could meet with us. Before I had started grad school this approach would have sent me into a panic attack, but by now the fly-by-the-seat-of-your-pants-approach (championed by both my advisor and my boyfriend) is standard. We visited several collaborators, hunted for caterpillars, and set up sheets at night before parting ways – I stayed a few extra days to be with my family.

Here are some highlights from the trip. You will notice a severe lack of caterpillars – there were hardly any to be found! Not sure if it was the weather or the time of year?

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One-eyed sphinx (Smerinthus cerisyi), came to a blacklight in Golden Gate Canyon, CO

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Dueling hummingbirds, Golden Gate Canyon, CO.

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Acronicta exempta, Castle Rock Canyon, CO. I captured 15 males that night, but no females!

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Our set-up at Castle Rock Canyon. I went blacklighting with a colleague who works at the Denver Museum of Science and Nature, so we had lots of equipment to play with. It was the best night of blacklighting of the whole trip.

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Obligatory shot of the scenery. Just outside of Boulder, CO.

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Went up to Gold Hill with my family to see the town, the views, and have a delicious 6-course dinner.

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Click for a bigger view!! Somewhere on Rt. 70 west.

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Me and my mom ❤

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Last stop – curation at the Denver Museum of Science and Nature! I got to sort some drawers of Acronicta, mostly unidentified and with other moths mixed in. I only got partway through after a few hours though, so I need to go back and finish!

I had a wonderful time in Colorado, and really hope it’s not too long before I can visit again. Besides, next time I need to get some female Acronicta and some eggs!

Time for a change of clothes

This great video was shot by my friend Sam Jaffe, expert caterpillar wrangler. He is spending his summer bringing caterpillars to farmers’ markets and science museums as entomology outreach for children. He specializes in the big ones, like this Hyalophora cecropia caterpillar. He managed to catch it as it was molting into the next instar:

He’s also an indefatigable moth hunter and finder-of-caterpillars-on-the-undersides-of-leaves. If you are in the northeast and want to see one of his shows, check out his facebook page: The Caterpillar Lab.

Fuzzy babies

Lots of fuzzy baby caterpillars here in the lab. Right now these two species look pretty similar, but the differences will start accumulating in the next few instars. Currently they are less than a week old. The first two photos are the babies from this post!

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Acronicta hastulifera, second instar

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Acronicta hastulifera, second instars

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Acronicta americana, second instars (and molting into third)

Beauty

I love this caterpillar. I wish that more than one had survived from the eggs the mother laid, so I could preserve one as a voucher. I was considering preserving this one, but today I noticed it was beginning to pupate in the bottom of its container. I guess I will wait for it to emerge as an adult.

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Acronicta sp. (brumosa? afflicta?), mother collected in Big Bend, Texas

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Acronicta sp. (brumosa? afflicta?), mother collected in Big Bend, Texas

Babies everywhere

300. That is how many little Acronicta hastulifera caterpillars hatched this weekend (click here to see the mother). Actually, there were probably more than 300, but I stopped counting.

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Developing eggs, two days before hatching.

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Lots of little first instars.

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As you can see by the giant holes in some eggs, many of them ate their egg-shells before wandering off.

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Babies on their host plant, alder (Alnus). Exploring a bit before settling down to eat.

The big hatching event happened on Sunday. It’s a good thing I came into the lab, because by Monday they would have been dead without food. I then became incredibly nervous that I might not have given them the right host plant, but they have been producing a large amount of frass (poop). Hurray! I get so protective of my caterpillar babies. This is what they look like today:

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Frass machines.

They are going to become wonderfully fuzzy caterpillars as they grow. I can’t wait!

Green and orange and purple

Here are some more fun photos of Acronicta lepetita from Texas. Some of them turn orange during their final instar, some stay green, some even turn purple-ish. Luckily this species is quite sedentary, so it is relatively easy to photograph. This first shot is one of my favorites:

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Smile!

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Orange and green siblings.

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This one was not interested in being a model, it just wanted to continue nibbling the leaf edge.

Many caterpillars are known to turn purple-ish, red-ish, or pink-ish just before pupation. However this orange color change happens while the caterpillar is still feeding, sometimes up to a week before pupation. It happens in Acronicta vinnula as well. I wonder why a caterpillar would want to be orange while still feeding on green vegetation?

Happy egg dance

On Saturday night I joined a bunch of entomologists for the 5th Annual Moth Ball in Massachusetts. Lights, sheets, cameras, beer, hotdogs, snacks, and tents for staying overnight. What could be better?

I was also on a mission. One species my advisor has been telling me I need to get ahold of is Acronicta hastulifera. As an adult it is nearly indistinguishable from Acronicta dactylina, though their caterpillars are quite different. The best way to make an ID, then, would be to catch a caterpillar and rear it to adulthood, or to get eggs from a female and raise the caterpillars. This is not always easy to do.

I found a few Acronicta females at the moth ball, nothing terribly exciting. Though it wasn’t long before a friend of mine approached with the grand prize in his hands (from a nearby sheet): Acronicta hastulifera. A big fat female! Success! The rest of the night paled in comparison to that moment.

When I awoke in my tent the next morning (after only a few hours of sleep), the first thing I did was check her container for eggs. About a dozen big green eggs dotted the sides of the vial. Woohoo! Last night I set her up in a larger container, and she really let loose. I estimate 200+ eggs.

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Momma moth and some of her eggs.

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So many eggs! My favorite colors, too!

At first I was a little worried that all of the eggs were remaining green. With other species that is sometimes a sign they are infertile. But once they gain some spots and other coloration, you know the larva is developing inside. Like this:

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A close-up, taken with my little Canon Powershot through a dissecting scope eyepiece.

I hadn’t seen a spot pattern quite like that before (the things on top are the mother’s scales).

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Some of the freshly laid eggs, before gaining their spots.

Now I must be patient and wait for them to hatch. Most Acronicta eggs take five or six days. I’ll be ready with some Alder (their favorite food), and my camera to get pics of the little ones.

Texas Days 2/3 – Fort Davis

Oh right, Texas! It already feels like so long ago, we’ve been so busy here in the lab.

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Dedication.

Our second stop in Texas was Davis Mountains State Park, in Fort Davis. It was another long drive across flat, desert-like land. We saw several hundred (thousand?) wind mills, which created a very eerie landscape. Fort Davis provided an emotional refuge of mountains and trees. We arrived late afternoon, and promptly went for a hike to stretch our legs.

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The sky was very blue.

Everyone we had talked to said that west Texas was experiencing a several-year-long drought. When we arrived at the park, it became quite clear they were telling the truth. Trees were clinging to old, tough leaves. Grasses were brown and crunchy underfoot. Wildlife seemed scarce. Aside from a couple whiptail lizards, a ground snake, and some unruly javelinas, the landscape seemed eerily deserted.

By the time we set up camp and settled in it was getting dark, so we set up a blacklight. Not much came in other than micro-moths and midges. Disappointed, we hoped the next day would be more fruitful.

In the morning we got up early for some caterpillar hunting. Well, I went for a run and a workout first, but then we armed ourselves with beating sheets and sticks and began wandering around the campground. There were only a few other people in the park, so the park staff didn’t mind.

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One of the many geometrid caterpillars.

Abilene sure was lush in comparison! But we did not give up hope, and searched as many branches as we could reach. Each tap of a tree branch released plumes of dust, pollen, and dead leaves. Surprisingly, we found a bunch of geometrid caterpillars. I wonder why they were the most abundant?

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Acronicta sp. (afflicta? brumosa?)

After an hour of not-very-productive searching, Ben shouted “Brigette, I have a present for you!”. Sure enough it was a little Acronicta caterpillar on an Emory oak tree! Despite our renewed enthusiasm and re-doubled efforts, we did not find any more Acronicta in the park. This little caterpillar grew up to be quite interesting – it’s the one featured in this post.

After a quick lunch (which became our classic: gluten free wrap with sliced turkey and a dill pickle) we drove a few miles down the road to the Chihuahuan Desert Nature Center. A place so wonderful it deserves its own post, coming soon!

 

 

Green slugs

There are caterpillars called “slug caterpillars” due to their, well, slug-like appearance. They are the Limacodidae, and they are some of the most beautiful and bizarre caterpillars out there.

Not to be outdone, there are a few species in the genus I’m studying, Acronicta, which resemble the infamous slug caterpillars. Blobby green things that hide their heads while at rest.

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If slugs were green and had little spikes all over.

These caterpillars were raised from eggs laid by a few females I captured in Boerne, Texas. I am uncertain whether they are Acronicta vinnula (common throughout the eastern US) or Acronicta lepetita (native to southern Texas, and so closely resembles A. vinnula that I am unsure how to tell them apart). As far as I can tell, the caterpillars are identical to the A. vinnula I have raised in the past.

It appears that no-one has raised A. lepetita before. Someone please correct me if I am wrong.

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I like to imagine this is the caterpillar’s “lion roar”.

The most information I can find is that “the larvae feed on various plants”. Thanks Wikipedia, that’s quite helpful.

What might be more helpful is a look at the adult. Here is one of the mothers.

lepetita_motherI’ll throw this one out to you again. What do you think?

Waiting patiently

My caterpillar season is starting to gain momentum. Caterpillars are hatching, eating, growing, pooping. Getting eggs in the mail from collaborators. Running around campus to collect plants. And some of the caterpillars from my Texas trip are approaching pupation.

I was somewhat in denial of this fact until I saw the size of this guy.

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Acronicta sp. (afflicta?)

That is a FAT caterpillar! I’d never seen an Acronicta caterpillar look quite so much like it’s going to pop. It also wasn’t in a terribly good mood.

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This body language is fairly clear.

Today I found out why. I checked on Mr. Angry Sausage Caterpillar and it looked a bit… different.

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Have we met?

The bright reddish orange coloration and jet-black head were an impressive change. I have only seen this sort of change in one other species, Acronicta lobeliae, which also gains a black head and darker coloration before digging a pupal chamber.

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I’m waiting!

I realized this caterpillar had stopped feeding and was ready to pupate. Poor thing was waiting for the right substrate!

I put a piece of soft, spongy wood into the container, since most Acronicta pupate in wood. It found the wood within minutes, and within an hour had chewed a tunnel into the wood. It’s currently sealed up, where it will remain for a couple months until it is ready to emerge as an adult.

I’m still not entirely sure which species this is. It was collected in Fort Davis, Texas. My guesses are either A. afflicta or A. brumosa. What do you think?

Ryerson Lab

Functional Morphology, Sensory Biology, Behavior, Biomechanics

I spell it nature

Trying to make sense of the world through science and language.