Shy Cosmet

Back in the fall I spent many nights at Tommy Thompson Park in Toronto with a sheet and blacklight, looking for moths. I caught many, all, of course, new for me, since I was just getting into moths and wasn’t familiar with anything yet. But I also caught a few less common species, and some notable things. The above moth is a Small Mocis, Mocis latipes, a very rare vagrant up from the States into Ontario. I gather there’s just a handful of records for the species in the province. And I got two that season!

So why do I mention this now, in August?

Shy Cosmet, photo taken by Susannah at Wanderin’ Weeta

A couple days ago I got a note from Susannah over at Wanderin’ Weeta (With Waterfowl And Weeds) that she’s finally got some results from an experiment she’d begun back in the winter. She had read my post back in the winter about the cattail caterpillar, the lavae of a moth that makes cattail heads go all fluffy during the winter. She had also noticed fluffy cattail heads where she lives in the Lower Fraser Valley of BC, and decided to investigate. All online resources indicated that the Shy Cosmet, the moth whose larvae I found in my cattail heads, did not occur as far west as BC, so when she found caterpillars in her cattail heads, she contained them so she could see what they turned into. The answer? Shy Cosmets. The species was not listed on the recently-revised 2008 version of the checklist of lepidoptera (moths and butterflies) of BC, and folks at E-Fauna BC are checking in with the experts to see if there are any other known records for the species there. It’s quite possible that Susannah has the first documented record for the province!

Undescribed wasp sp., photo taken by Julie at Bootstrap Analysis

Then today, Julie at Bootstrap Analysis made a post about some wasps she found in her yard. Back in the fall she started a personal project to document all the wasps, bees and flies that she found in her yard – not all that different from someone who keeps a list of the birds or the butterflies that visit their garden (and I’m sure Julie does that, too). Aside from discovering some wild-looking species using her yard, she also found a new state record that fall in the grass-carrying wasp Isodontia elegans. Also last fall she found the above wasp which, when she couldn’t identify it, she posted to BugGuide.net for help. It turned out it was a relatively new species to science – it hadn’t even been described yet (all species have a formal “description” that is published wherein they’re given a scientific name and the details of the species that differentiate it from others are laid out, as well as other known characteristics and behaviour). The species was identified on BugGuide.net by a professor at the University of Guelph (my alma mater!) as a new one he was collecting data on, and will be formally described by him in the near future.

September 7 has been designated as International Rock-flipping Day. The event was inaugurated last year by Dave at Via Negativa, and went so well they’re doing it again. Dave and co-coordinator Bev of Burning Silo encourage everyone to go out on Sept 7 and flip a rock or two (or three or four if you’re having fun. Record and/or photograph what you find and send the results to Dave and Bev, whereupon they’ll gather everyone’s responses into a single spot and send it out to participants. You can post the results to your blog, put them up on your Flickr or other photo account, or, if you don’t have an online presence, simply send them off to Bev who’ll put them up on her site. Beyond just being a lot of fun, the project also has the potential to contribute to science by documenting species in places they haven’t been seen before, or behaviours that haven’t been observed, or other valuable information. More details at the official IRFD page.

So what’s the point of this whole post? That no matter what your expertise, no matter where you are, where you live, whether you have acres of land, a little backyard, or a balcony, you can still make valuable observations. It’s likely that all the big vertebrates have been recorded for your area, but there are thousands of invertebrates that are often overlooked because of their size and habits, plants that blend in to the rest of the foliage, and behaviours of animals large and small that are always interesting to observe and important to document. The one key ingredient to having success and finding things, though? You have to get out there and look! Isaac Newton was probably the only person to have science come to him…

Edit: This post was recently included in the 182nd edition of the Friday Ark, a blog carnival focusing on animals of all sorts.

I’m sure we’ve all seen these in our local wetlands, cattail heads that have become all poofed out as winter progresses, like so much cotton-candy on sticks. I’d never given it much thought before, and if I had I suppose I’ve just assumed that the fluff has something to do with the cattail releasing its seeds to the wind, much like milkweed does.

A few weeks ago, my mom bought the book Insects: Their Natural History and Diversity (with a photographic guide to insects of eastern North America) by Stephen A. Marshall. Steve Marshall is a prof at the University of Guelph, where I did my undergrad, and was one of the instructors leading the Ecuador field course that I took. I didn’t spend much time with him (I knew the other prof better), but he was a really nice guy. So I thought it was cool that Mom had got this book, and I sat down to leaf through it. I was primarily interested in the 40-someodd pages of moth plates, and while flipping through those I spotted an image of fluffy cattail heads. Intrigued, I read the plate caption associated with the figure.

Turns out, those fluffy cattail heads you see in the middle of winter aren’t just the cattail doing its thing. Sure, it will naturally begin to loosen the fluff and lose some to the wind. But the cotton-candy formations? They’re the work of a tiny, drab little moth called the Shy Cosmet (Limnaecia phragmitella). Its caterpillars are appropriately known as Cattail Caterpillars. They feed on the seeds of the cattail in the fall and spring, overwintering inside the head as a larva. In late spring they pupate and emerge as an adult moth in early summer.

In order to ensure that they have a secure home for the entire duration of their stay, they spin tiny silken threads that act as a web holding all the fluff inside. The cattail will still loosen its seeds from the stalk to try to spread them on the wind, but the caterpillar’s netting holds them in place. The result is a rather lumpy cotton-candy appearance.

I thought this was all pretty cool, so I did a bit of searching on the web and discovered a post about the Shy Cosmet, made recently, by Gerry Wykes at Naturespeak (he calls Detroit home, so is within my rather broad neck of the woods). In it he brought in a cattail head and gently dissected it to expose the caterpillars hiding within. Now, I suppose I could have just taken him at his word, but I really wanted to go out and have a look for myself. Insatiable curiosity. In the name of science, of course. I brought in two heads for good measure, and opened them up in a tub to contain any wandering worms.

Gerry indicated that it would take a moment or two for the caterpillars to poke their heads out of the fluff, that they wouldn’t be immediately visible. So I sat there and patiently waited. And waited. Nothing happened. No heads, no tails even, not a hint of movement. I’ll admit that they should all be dormant at this time of year, but since he’d had such luck with his coming out as soon as they were warm, I was beginning to wonder if I’d picked a dud cattail head, one that really was simply just loosening up its fluff.

So I started gently teasing apart the clumps. I found lots of what looked to be frass in with all the seed heads. The seeds are tiny, flat and boxy at the end, and brownish in colour. The frass, on the other hand, was gray and round, spherical. There was lots of it, but no caterpillars associated with any of it.

Finally, after standing with my head bent over this dish for many minutes, I discovered one. Only one, just a single, lone, under-developed caterpillar. Perhaps the cattail head had already been picked over by foraging birds and this was the only guy to have survived. Perhaps there never were many to begin with, maybe I missed one or two. But I went through the entire two cattail heads and only found one. By the time I was done, they looked like this:

Here’s the caterpillar. I found him tucked in a clump of relatively undisturbed fluff, nearly comatose. He wiggled a bit when I first picked him out, but didn’t go anywhere. Gerry was describing his caterpillars crawling all over the place, making getting a good photo difficult. Mine was very photogenic.

This is the caterpillar posed with my mom’s finger for scale. He was tiny. Tiny tiny. This is why I wouldn’t be surprised if I missed a couple others, although I was paying close attention. Below is the caterpillar beside a measuring tape. You’re looking at the inches side of the tape. Each one of those black dashes is 1/16″. See? Tiny tiny, it’s not that my mom has big fingers…

I actually found the dried husk of an older caterpillar in the fluff as I was starting to clean up. This gives you an idea of what it should grow to before pupating. He’s got a ways to go.

These little caterpillars form one of the primary food sources for Red-winged Blackbirds upon their arrival here in the spring. It seems like they’d need to eat a lot of them to get much nutrition, but evidently it works for them. A couple springs ago I got a photo of a female Red-wing poking at cattail heads. I thought at the time she was looking for nesting material, but having learned this, it seems apparent that she was actually searching for caterpillars. Who knew? Cotton candy indeed.

As for the book, I highly recommend it. It’s got great photos for an identification reference, and excellent information to complement them. The notable entomologist E.O. Wilson is quoted on the cover: “I wish I’d had Stephen Marshall’s book when I started out in entomology. Its countless photographs and notes bring alive the vast diversity of the insect world.” That’s like Roger Tory Peterson endorsing a bird reference book. There’s so much cool stuff in the book, lots to look at. The only downside: it weighs a tonne. Probably almost literally. At 730 pages and nearly two inches thick, a field guide it’s not. Still, it has the best collection of printed moth photos I’ve seen, plus so much other stuff, I ended up getting a copy myself (should be in the mail). It retails in store for $95, though generally cheaper online, but I found a copy on eBay for $33 plus shipping, so if you look around you should be able to get a good deal on it. Amazon has it on sale for $60. It’s also got a couple images of inside the book so you can take a peek before you buy.

Tag: Shy Cosmet

Get out and look!

Cotton candy for blackbirds