Cecropia Moths


When I visited the Ned Smith Center for Nature and Art, near Millersburg, PA, during the book tour, I got an opportunity to meet my very first Cecropia Moth (I’m posing with it, above). It was a captive-reared individual that one of the guys involved in the event had raised himself from a caterpillar; it had eclosed (emerged from its cocoon) that day or the day before, so he’d brought it to share with the attendees. Another person brought a female they’d reared to the event in Athol, MA, hoping she’d lure in some males (she didn’t, but she was still beautiful). (A third person brought a captive-reared female Luna to the event in Detroit, MI, and there was also a captive Luna at the Ned Smith Center; and someone else brought a reared Polyphemus to the Ithaca, NY, event – I was grateful to all these folks, it was so great to have these flashy silkmoths there to show off!)

They’re indeed impressive moths. They’re also not that uncommon, so it’s a bit of a surprise that I’ve not encountered one before at my lights; I’ve got the other silkmoths, the Luna and Polyphemus, Imperial and Io, but never the Callosamia or Hyalophora species that share this sort of pattern. I’m supposing they’re not as attracted to lights as the other species are; some species of moth aren’t.


Then last night I came around the corner to check my moth sheet and there this guy was, waiting for me! Looking a little natty, with that big tear up his left forewing, and some nicks out of the edges, but it didn’t matter; it was a Cecropia, the first wild individual I’d ever seen, and also my first for Ontario. I went searching for a container I could put it in, to hold it in the fridge till the morning for a photo.

I had a bunch of larger containers stacked at the side of the house, and as I bent over to grab them I suddenly realized…


…the silkmoth cocoon I’d collected last week had hatched, and there was a fresh Cecropia Moth hanging inside of the wire cage I’d put it in.

And suddenly it all made sense, why there was a Cecropia at my light this evening. The differences between the sexes of Cecropia are somewhat subtle, involving the size of the antennae (larger in males, for detecting the female’s pheromones) and abdomen (larger in females, as it’s full of unfertilized eggs), and I’m not really experienced enough to tell the difference; but I’m guessing this one was a female, and after she emerged she started releasing pheromones (“calling”) that drew the male in.


This is the cocoon (now empty). Last winter (’10-’11) I discovered two Promethea Moth cocoons that I collected and hoped to see hatch out (they’re also moths I’ve never seen adults of) but they turned out to both have been parasitized. This winter I found two cocoons that I was pretty sure were Cecropia, though I thought might perhaps be Polyphemus, which are very common around here and build similar-looking cocoons. I didn’t want to collect them up and have them hatch in captivity while I was on the tour, so I waited till I got home. By that time one was already empty, but the other still had something in it; I hoped it was a moth, not a parasite.

I cut off the small branch it was attached to and brought it home, making a wire cage to protect it and also to contain the moth once it emerged. I’d been checking on it regularly, but I guess I hadn’t looked yesterday. Cecropias apparently typically emerge around mid-morning, which I guess gives their wings time to expand, dry and strengthen prior to the night’s flight.


By the time I shut the light off and went to bed, three male Cecropias had come in to my sheet. I collected them up and set them together for this photo, before carefully moving them out into dense vegetation, just in case they didn’t fly off once the light was turned out (some moths, once they’ve arrived at the sheet, don’t leave again; and silkmoths would be pretty obvious to predators).

I find it interesting how much variation there is in the pattern of their wings. The one on the top, for instance, has very bright, well-marked spots, while the middle one has very little white in the spots. Of course, this is pretty well true for most species of moths, that there can be quite a lot of variation, but it’s more noticeable in some than others.


One of the males, showing off his feathery antennae. The receptors on these are so sensitive to the female’s pheromones that he can (supposedly) detect her from up to a mile (1.6 km) away. Which is pretty astounding, when you think about it, even considering that these moths are North America’s largest, at up to a 6 inch (15 cm) wingspan. On one of my checks one of the males was just arriving, and as he fluttered about the area, circling around the light  and along the house wall, between his size and the way he flew you could almost have sworn he was a bat if you didn’t get a good look.


This is the moth that hatched out of my cocoon. I saved her for a photo today, and she’s back in the fridge again to wait for this evening; I didn’t want to release her mid-day when her giant size would make her pretty eye-catching to predators as she flew away. I’ve been toying with the idea of catching one of the males she calls in and putting them together in a captive space, to hold her until she lays her eggs in order to raise them. I think that would a lot of fun, to watch the caterpillars develop and end up with a large brood of adult moths that could be released next year. But I think it would also probably be a lot of work… So I’m yet undecided. I’ll keep you posted.

Book tour schedule


I head off on the book tour for the Peterson Field Guide to Moths in a week and a half! I’m busy finalizing details and getting myself organized to go; lots of little things to take care of before then.

Here’s the final tour schedule. If you have a question about any of these events, please contact the person listed (if it’s regarding the facilities) or myself (if it’s regarding the event details, or if no person is listed).

*Event attendees may leave early if you need to go – we won’t trap you!

April 29
Dearborn (Detroit), Michigan

8pm – midnight*
University of Michigan-Dearborn Environmental Interpretive Center
Presented by UMD with Rouge River Bird Observatory
More information (with link to map).
Please RSVP with this form.

April 30
East Liberty (Columbus), Ohio
8pm – midnight*
Big Darby Headwaters Nature Preserve
Presented by The Nature Conservancy Ohio
More information.
Please RSVP with this link or email sross at TNC.org by April 25.

May 1
Wheeling, West Virginia
7:30 – midnight*
Oglebay’s Good Zoo
Please RSVP to Penny Miller by email (pmiller at oglebay-resort.com) or phone 304-243-4027.

May 2-5
New River Gorge National River, West Virginia

New River Birding and Nature Festival
This is a registration-only event. If you’re interested in participating, visit the festival’s website here.

May 6 – day off for sanity

May 7
Davis, West Virginia
7pm – midnight*
Canaan Valley National Wildlife Refuge Visitor Center
More information.

May 8
Millersburg, Pennsylvania
8pm – midnight*
Ned Smith Center for Nature and Art
More information.
Registration suggested but not necessary. Members free, non-members $3.

May 9
Hockessin, Delaware
7pm – 9pm* (or later)
Ashland Nature Center
Presented by Delaware Nature Society
More information.
This appears to be listed as members-only, which I hadn’t realized. If you are interested in coming to this event but are not a member of the DNS, contact me and I’ll see about sneaking you in. :)

May 10
East Brunswick, New Jersey
8pm – 11pm*
East Brunswick Cultural Arts Center, Playhouse 22
Presented by Friends of the East Brunswick Environmental Commission
More information.

May 11 – day off to visit friends

May 12
Athol, Massachusetts
8pm – midnight*
1542 Pleasant Street, Athol
Hosted by Dave Small of the Athol Bird and Nature Club
For more information contact Dave by email (dave at dhsmall.net) or phone (978-413-1772) (event posting here)

May 13
Danby, New York
8pm – 10:30pm* (or later)
Danby Town Hall
Presented by Danby Conservation Advisory Council
More information.

Early tent cat nests


A week ago when I was out with Raven a glint of white in one of the black cherry trees in our back fields caught my eye. Wondering if it could possibly be a tent caterpillar nest so early in the season, I checked it out. Sure enough, it was. This feels very early to me, but I admit I’ve never caught the nest at such an early stage before, barely started. Normally I check in when it’s already the size of my fist or thereabouts. I start noticing them (without having to consciously search) in early May usually. Was it just that I was paying attention this year?

Part of the reason I was watching was because of the warm spell we had in March, of course. I worried that it would not only accelerate the budding-out of the trees and shrubs, but also the growth and emergence of early-spring species. I did, in fact, have an Arched Hooktip (a moth) show up at my light one night at the end of that week; ordinarily the species first shows up in mid-May, so it was nearly two months early. It didn’t seem a stretch to think it might have prompted the tent cats out prematurely, too.


When I investigated more closely I discovered all the little caterpillars in this particular nest were dead; blackened and unmoving. We’d had several nights in a row of freezing or just-below temperatures, including one hard night of several degrees below. I wondered if that had killed them. Tent cats use their tents to help thermoregulate, and I would assume that, since we still get frosts potentially as late as mid- to late May most years, it also serves as protection against frost. But the little nest of these cats was still so small, perhaps the size of a plum. Maybe it didn’t provide enough protection.

When I did my usual late-winter walkabout searching for tent caterpillar eggs I only found a few clusters, all on the same tree. The other trees that have had them in most past years didn’t have any, so I was already starting to wonder if it’d be a year of low abundance for the species. This freeze won’t have helped, if it’s killed all the caterpillars from this egg cluster. I couldn’t really tell if all the eggs had hatched or only some of them. I’ll hope some hadn’t hatched yet and might go on to build a new nest.


In another field I found a second nest. This one was larger and the caterpillars on it obviously older – and, happily, still alive. They were clustered together sunning themselves on the surface of the nest, which they’ll do on cooler days. This nest was closer in size to an orange, so I wondered if the extra layers of silk had helped protect the caterpillars against the cold.


They’d already started making their silken trails up the branch from the nest to their feeding location. This is one of the reasons tent caterpillars appeal to me so; there’s so many neat aspects to their biology that are fascinating to look for. They leave this trail as they walk so they know where the nest is when it’s time to return. The nest is their protection from both the elements and predators, so you can understand the desire for a lifeline like this.


These were the buds the line was leading up to, though. The whole tree was like this. There can’t honestly be enough plant material there to sustain them yet, can there? I guess they’ve got little mouths and wouldn’t eat very much, so maybe there would be. The nest was full of frass (see the little brown dots in the photo with the sunning cats), so they were obviously eating something, and it was orangey-brown like the bud sheathes here.

I’ll be keeping an eye on these guys over the next little bit to see how they do – not that there’s much I can (or would) do if the weather goes cold again. But I like to keep tabs on my local families of wildlife, and tent cats are such easy ones to monitor…

A quick note re: the moth guide

Currently Amazon lists a Kindle edition of the PFG to Moths as being available for pre-order with release on April 17. I inquired with our editor about this, and there will be no Kindle/ebook edition released anytime soon. The field guide format is trickier and more involved to convert to ebook than a standard narrative/text, and the tools to do a good job of it are fairly new. The way the information is stored in the computers is apparently a little confusing and results in Amazon putting this sales link up (I gather this has been a problem for a while and the publisher has been looking at changing the computer system to try to address it).

There may well be an ebook version in the future, but it won’t be available on April 17. So if you’ve pre-ordered a copy, you’ll need to cancel and order the print copy instead. Sorry about that, everyone!

March Moths (and a few PFG to Moths plates)

Goat Sallow - Morrison's Sallow - Three-spotted Sallow

With the gorgeous weather yesterday, I knew there’d be moths flying come evening. I put my mercury vapour light out, even going to the trouble to dig out and pin up my white sheet in front of it. And I wasn’t disappointed! I got a great diversity, 15 macromoths of 11 species, and another dozen or so micros of the agonopterix and acleris variety.

I collected up one individual of every species except the Straight-toothed Sallow, which was the First Moth of 2012. The top shelf of the fridge was satisfyingly crowded. Since I’ve already got dozens of photos of these species on the plain background I usually use for species portraits, I thought I’d do a collage, in groups.

The above group is all the sallows (again, minus the Straight-toothed, which I sort of wish I’d brought in just for completeness). Top left: Goat Sallow, Homoglaea hircina; top right: Morrison’s Sallow, Eupsilia morrisoni; bottom: Three-spotted Sallow, Eupsilia tristigmata.

Small Phigalia - Half-wing - Spring Cankerworm

There are three early-spring geometers that you can pretty much count on on any given night in March and early April. I was pleased that all of them turned up last night – just singles of each. Top to bottom: Small Phigalia, Phigalia strigataria; The Half-Wing, Phigalia titea; and Spring Cankerworm, Paleacrita vernata. Having this photo with them all in the same shot helps emphasize the size difference between Small Phigalia and The Half-Wing.

Dowdy - Dimorphic - Hemina - Grote's Pinions

And finally, the pinions. The third group of overwinterers who’re likely to come to lights early in the season. I was surprised there were so many species last night, ordinarily I just get the bottom one here. Top: Dowdy Pinion, Lithophane unimoda; middle left: Dimorphic Pinion, Lithophane patefacta; middle right: Hemina Pinion, Lithophane hemina; bottom: Triple-spotted Pinion, Lithophane laticinerea.

These guys have distinctive shapes and so are easy to pick out, usually. There are two shape types: the long, narrow gray ones, and the bow-winged (look at the outer edge), shoulder-padded ones. Within each of the shape groups there are a number of look-alike species. For instance, Hemina and Wanton Pinions look very similar, but Heminas tend to be orangier with more diffuse markings than the grayer Wantons. Likewise, Grote’s and Triple-spotted can be hard to tell apart, but Triple-spotted typically are a smoother gray with the ST line often sparser/dotted or nearly absent compared to the rougher-gray Grote’s.

Since we’re still a month out from the release of the moth guide (but only a month! April 17!) but the pinions are flying now, I thought I’d scan in and post the identification plates for the group. Enjoy!

For all of these, click on the image to see a larger version.