Monday, May 2, 2011

silver-spotted tiger moth ~ 05/02/11 ~ at home

silver-spotted tiger moth caterpillar (or nameless arctiid moth) feeding on Monterey pine
Lophocampa argentata (or L. sobrina) feeding on Pinus radiata

I laughed at how this caterpillar chomps the pine needle like it's eating a giant, long green bean. To see how beautiful this caterpillar is see my 03/15/11 post. As a recap, the pictures of the silver-spotted tiger moth caterpillars (Lophocampa argentata) on BugGuide were browner than what I found in the Carmel Highlands. Hmm? I consulted Chris Grinter of The Skeptical Moth who suggested, based on my location, this caterpillar is L. sobrina; he has since made a comment on BugGuide. Unfortunately, I have not found any other L. sobrina caterpillar images correctly identified on the internet to compare with mine. Actually, there is some question among the experts whether L. sobrina (sorry, there's no common name) is indeed a distinct species from the silver-spotted tiger moth. I also queried Jerry Powell and Paul Opler, co-authors of Moths of Western North America, a hefty book which was released last year. All three moth experts had differing opinions, but Paul had the best advice: raise the caterpillar to an adult to obtain a positive ID. Adult Lepidoptera are better documented and easier to identify. So, that's what I'm doing.

I collected my first caterpillar in the Carmel Highlands on 03/31/11. I found a second caterpillar on 04/20/11 at home and within feet of our local subspecies of the Douglas-fir, L. argentata's favored food. Then on Easter 04/24/11 in the Highlands, I gathered a much larger caterpillar on top of California hedge nettle (Stachys bullata). Finally, I found a fourth caterpillar climbing up the wall nearest the coast Douglas-fir at home. I'm guessing I collected it 04/30/11 while sitting outside to get fresh air, because I returned home from the hospital the previous night. As soon as I found it, I asked Andy to go cut more caterpillar food for me. Gotta love the man! After days of sitting by my hospital bed watching the Food Network (we don't get it at home) in between doctors and nurses visits, while tubes and wires connected to fancy machines beeped and hummed, he then obliged me by tromping through the park to get clippings from various trees. Well, you can guess where my priorities are... must feed my caterpillars first!
silver-spotted tiger moth caterpillar (or nameless arctiid moth) on coast Douglas-fir
Lophocampa argentata (or L. sobrina) on Pseudotsuga menziesii var. menziesii

I want to show off the cute lemon yellow prolegs of this caterpillar. I have to say, that while these caterpillars did eat some coast live oak (Quercus agrifolia var. agrifolia), they seem to prefer the Monterey pine and coast Douglas-fir. I even tried to feed them various other plants, but they were totally not interested. They also like to feed during the day and get very still at night. Do caterpillars sleep like us humans?

Lophocampa argentata (or L. sobrina) cocoon

This was the largest caterpillar collected from the Highlands on Easter and it started making a cocoon the day before this picture on 05/01/11. Notice the loose hairs mixed in with its silk to make the cocoon? Unfortunately, I disturbed it to move the remaining caterpillars into their roomier home with fresher food.

Lophocampa argentata (or L. sobrina) cocoon lit from behind

I had to see how far along this caterpillar was to pupating, so I held the cocoon up to the light. It wasn't very far along. I've since looked at it again against the light and it looks like it's shed its larval exoskeleton and has the distinctive pupal shape that looks like a turd. I'll try to get a picture of that later.

Lophocampa argentata (or L. sobrina) cast exoskeleton
This may look like a dead caterpillar, but it's not. This is what is left behind when a caterpillar molts in order to grow into a larger caterpillar. I try not to repeat better information that can be found on the web, so if you really want to know, go look it up yourself.

Apologies for this atypically lengthy Nature ID entry. All these pictures were taken on the same day as this post's date of 05/02/11. I've missed doing my blog while I've been sick. I'm now 13 days behind with my posts and I want to catch up. Watch out for multiple posts in any given day...

ps 05/27/11 - Another caterpillar molted this morning and it's very white compared to my other remaining caterpillar of this sp. I was nervous, because it didn't move much for a couple days - I had one die last weekend. I took a close look at the dead one and it looks like some parasite had attacked it. There were numerous tiny cream-colored spots on the underside of its body. I never did get around to pulling out my dissecting scope to take a magnified look.

pss 10/16/11 - Greg Monson, Founder and Head of Production at Lost Nomad Media, requested permission to use the first photo above. With his permission, here's what he said, "I found your post on caterpillars while I surfing the internet. I'm currently editing a research documentary for a professor at the University of Arizona, and your first picture of the caterpillar eating the needle is perfect for a segment in the film where I mention how pine needles are a form of sustenance for insects." He goes on to say, "I'm wondering if I could have your permission to use the photo in my video. The film is a 12-minute short documentary on a research experiment being conducted in Colorado, where they are looking into the role that terpene molecules from pine forests play in generating clouds. It will be published on youtube, and the University of Arizona website, and I will be happy to give you credit for your photo. This is the first of a series of videos my company is producing to promote outreach from the scientific community to the public." I'll add a link to the video when it becomes available.

pss 01/11/12 - Here's the link to the video:


Anonymous said...

I've been too busy to follow blogs much so just found out you've been sick. :-( I'm so sorry - but GLAD you are on the mend and how sweet is it that your caterpillars got tended to meanwhile?!

Nature ID (Katie) said...

Thank you, Janet. I've missed your comments. I have over 1000 new blog posts that I haven't followed since all this happened.

Actually the poor caterpillars were starving by the time I got home. Two of them still don't look so good.

I have a feeling I'm going to be sick once I get the hospital bill. Can you believe my insurance has already sent a letter saying they may not pay, because of some fine print stuff?

Anonymous said...

I saw one of those little critters in the Santa Cruz Mountains! :) Cute, aren't they?
- Julian

Cindy said...

Watching these caterpillars up close with you is very interesting. Finding a diet for them must be hard. I wish your insurance co tried as hard to take care of you as you are trying with the caterpillars.

Anonymous said...

You may need somebody to help advocate for you with insurance co. if you are not feeling fully well when the s*** hits the fan. It's a disgrace how they weasel out of paying claims.

Guest said...

Can you help me? I started taking care of Silver Spotted Tiger Moth caterpillars a couple years ago (we are in Western WA and our apartment complex has them all over the place) as a little summer project to do with my toddler (now preschooler). Our first year we just had one caterpillar and made it a shelter, fed it pine, etc. and he made a cocoon, hatched into a beautiful silver spotted tiger moth and we let him go and watched him fly away. So last summer we did it again, found two caterpillars this time and put then in the shelter we had built for the first one we cared for, fed them pine just like the last time and they made cocoons but then they both died. One of them never hatched at all, the other one did hatch but the wings were small and the body was deformed. I've been trying to figure out what I did wrong this time. Today we found another caterpillar and I decided to do the project with her again, but I don't want the same thing to happen as the last two that died. I don't want to hurt the little guy and if I was in any way responsible for the deaths of the two last year I don't want to make the same mistake again, whatever it was. Anyway so my question: do you have any idea as to why these two died? They were in a tupperware with a mesh top (same shelter I've been using that seemed to work with the first one) so I don't think any predator or bug got to them. I fed them pine but maybe they didn't get enough? Also, their cocoons were fused together. Maybe that had something to do with it and I should have kept them separate? I have no clue. Anyway, any advice and help would be appreciated. Thank you :)

Katie (Nature ID) said...

Guest, sorry, just found this comment. Please send me an e-mail so we can continue this conversation (top of page, on right is "View my complete profile", click that, and then click Email or click jokyungee in (c) notice below). Thanks.

Guest said...

Thank you for your reply. I've sent an email to you.