As well as recording and photographing butterflies and moths, I’ve also reared caterpillars. My first attempt was years ago – I tried to keep some Large White caterpillars in a wormery but after they turned out to be miniature Houdinis I was advised to put them back on the nasturtiums!
Caterpillars would not enter mein haus again until October 2009 (a month after butterflies migrated into my life in a big way) – this time I took eight ‘Brown Furry Caterpillars’ under my wing. I identified them as Ruby Tigers (my first caterpillar of this year, incidentally) and kept them at home, in a large modified plastic bottle outside, with the intention of rearing them and releasing them back in Murlough where I found them. They fed on ragwort and dandelion for a few weeks before settling down as the colder weather blew in.
That December, I brought four of them indoors for a night, and one immediately set about spinning a cocoon to pupate in. I hadn’t intended to make them do that and since the caterpillar had moulted his hair to make the cocoon I was loth to put them back outside. So I kept those four indoors, and the caterpillar went ahead and pupated inside his cocoon.
Ruby 1, or Ruby-wan-kanobe as I called her, emerged from her chrysalis on the 4th of January, and ran around with her wings every shape, before settling overnight to let them dry flat. She was less than an inch long, with red-brown forewings and vivid pink and black hindwings. It was too cold to release her so I kept her inside for her month-long life. She didn’t have a mate, so after a while she just began laying unfertilised eggs willy-nilly!
The other indoor caterpillars showed no intention of spinning cocoons for a while, and when two of them did, it turned out that they had been parasitised by ichneumon wasps, which spun their own little white cocoons on the dead caterpillars. The other indoor caterpillar died but no parasites emerged. (Sorry for being morbid!)
The outside caterpillars didn’t fare much better: the first to spin a cocoon (Ruby 5) had one parasitic fly, but Ruby 6 pupated successfully. Sadly, the last two had ichneumons.
Ruby 6 (Ricky) was the only one out of eight that survived to see Murlough again. She emerged on May 21st and I released her back where I had found her in Murlough, two days later. It’s a wonderful feeling to care for something and let it grow and release it back where it belongs!
With the project complete, I can draw a few conclusions about the Ruby Tiger moth Phragmatobia fuliginosa.
- The species overwinters as a fully grown larva, spins a cocoon in March, pupates in April and emerges in late May.
- Caterpillars parasitised by ichneumon wasps seem to attempt pupation later than healthy larvae, similarly to the Marsh Fritillary (ref. Jesmond Harding).
- Caterpillars are also parasitised by a large (5-10mm) Tachinid (?) fly, which also parasitises the Drinker and Garden Tiger caterpillars (more about them in a later post).
- Parasites kill the caterpillars after they have spun cocoons and prevent them from pupating.
- There were high rates of parasitisation in the Ruby Tiger caterpillars in Murlough at the end of 2009.
- The Ruby Tiger pupates for 20 days indoors, and at least 35 days outdoors.
Hopefully someone reading this might find it interesting or even important!
Species Study 2, project A: Ruby Tiger (Phragmatobia fuliginosa)
I’ve just found a Ruby Tiger Moth larva, so very helpful. Was wondering what it ate (I tried apple slices and dried leaves), but you mentioned Dandylion, and there is plenty outside so this must be the stuff….
Thank you
Steve
Hi Steve,
Best of luck with the Ruby! It’ll love dandelion – and a whole lot of other plants too so you could experiment if you like.
However, it’s quite late in the year, so if it doesn’t go for dandelion then you can be pretty sure it has finished eating and is ready to hibernate. If you give it dandelion and it just wanders around for a few days, put it outside in a container. I don’t know what the very best ‘furniture’ to put in the container is, but my caters just huddled together on a stick. From what I gather it’s best to give them something natural to cling to. And best put the container in a shady place, put airholes in the side but make sure it isn’t going to fill up with water when it rains… just common sense stuff I guess.
Samuel
Hi 🙂 thanks for the helpful website! i just found what seems to be a Ruby Tiger caterpillar outside in the street, its a freezing cold day and it was all curled up, but i brought it back and kept him inside a little plastic tray with some leaves and finally after about 2 hours he has uncurled but hes just sat there, not doing much at all, is that normal behavior? or in your opinion should he be a little more active? thanks if you get to reply 🙂 i just want to help the little guy out!
Hi Beth 🙂
He could be just resting – it might take a while for him to adjust to the new conditions. I would put him in an unheated room, leave him alone and don’t move him about too much. You’d better keep him contained though – like in a jar, margarine tub etc. – because if he does wake up he’ll not stay in the tray!!
What kind of leaves have you given him?
Sam
Thanks for the reply! well i have had him for a few days now, i am keeping him in a plastic bottle with air holes, given him plenty of twigs and dandylion leaves and he has moved around a bit and started eating one of the leaves 🙂 hes still not as active as i thought he would be compared to caterpillars i have seen before… but he seems to be on the mend! im keeping him in my bedroom on the windowsill and i rarely have the heater on in there, i will keep you updated on any progress! realy appreciate the reply thanks for that and have a nice day 🙂 x
hi I found a ruby tiger caterpillar so brought it home, put it in a jar and it started it cocoon straight away…but then I seen 2 eggs sort of thing appear inside cocoon and was so confused, this morning I noticed there was a fly inside jar kind of silver stripped looking fly with bright red eyes and then another fly came out 2nd egg thing lighter colour than 1st bright red eyes what are these?? 1 looks like it has a sting my daughter is devastated there is not going to be a moth/butterfly as ruby tiger caterpillar is all curled up and dead. one more thing are these flies harmless? and what shall I do with them x
Hi Nichola. I’m sorry for not replying sooner as I have been busy with exams. Your caterpillar has fallen prey to parasitic flies! They’re probably harmless to humans so don’t worry. The flies lay their eggs in a caterpillar and the larvae hatch out, feed and develop and eventually kill the caterpillar as it is pupating. The maggots come out and pupate themselves (the “eggs” you saw), then eventually emerge as adult flies. It’s sounds a bit gruesome but that’s just nature! The maggots are just as important in nature as the caterpillars – they gotta eat too!
I hope this hasn’t put you off rearing caterpillars! Most caterpillars manage to avoid parasites so chances are you’ll find plenty more for your daughter to watch turn into beautiful butterflies and moths! It’s such a rewarding hobby.
Best wishes
Sam
Hi Sam, Susan, Ivan,Athena and Robin Bruce out here in Bellaghy have just found a Ruby Tiger caterpillar. He looks pretty fully grown and is currently in with their Garden Tiger caterpillars. We are hopeful we have rescued the Garden Tigers before anyone could get to them, but the Ruby Tiger was found already pretty big so we shall see! I shall let them know to keep him cool and give him some sticks and dandelions. Really helpful page, thanks for the advice! 🙂
Good stuff Catherine, glad to be of service! 😀
It looks exactly like a Ruby tiger but It has not pupated yet and its September
Hey There
I Have A Ruby Tiger Moth In A Cocoon
And I Didnt Know How Long He Would Be In It For (Or She) And I Was Wondering How Long It Would Take.
The Lil Guys Been In It For About Two Days Now, So I Didnt Know If It Takes A Long Time Or A Short Amount Of Time To Become A Moth.
Thank You!
-Kayla
Hi Kayla 🙂
It’ll probably emerge within a few weeks, if it is a Ruby Tiger. If it’s something else (like a Buff Ermine) it could be in there until spring comes round. Keep it in a container in an unheated room / shed / outide shelter and check on it now and then.
Ruby Tigers normally hibernate over the winter as full-grown caterpillars and only spin cocoons (to pupate in) in spring. If the moth emerges this side of winter, don’t release it as it will be cold and in any case unable to find a mate at this time of year. You can keep it indoors in a fairly large container (to give it room to fly) and provide a bit of sponge soaked in sugary water to keep it going.
I hope you do get a moth – it’s touch-and-go because sometimes caterpillars have parasites which kill them in the cocoon before they pupate. Best of luck!
Sam
Hello I have found a Ruby Tiger and it is November here in Alabama but we have had high seventy degree weather. I put it in a container and it has started to make a cocoon immediately on a dead leaf my son put in there. I was concerned it did not use the stick. Is that normal and what do I need to place the container I hope I can avoid parasites my 5yr old daughter would be crushed? This is my first attempt at this and feel so lost. Should I take all the leaves out put in some dirt any help would be appreciated. Also how long does it normally takes for them to make the cocoon it started hours ago and still has not finished. Thanks glad you had this posting.
Hi Sherida,
Everything sounds fine – no need to worry! It’ll finish the cocoon in a day or so – just leave it on the leaf, soil isn’t really needed. You just need to keep it out of the sun in a closed container (indoors or outdoors) and check on it now and again. When the moth emerges it’ll find somewhere to sit and dry its wings – a stick is ideal but it might feel like using the side of the container.
The caterpillar should pupate in a week or so – through the cocoon you might be able to see the shiny skin or smooth outline of the chrysalis. As for parasites – well, it might already have them in which case you’ll get flies or wasps instead, but again, don’t worry – it’s all natural! 🙂 If it does get to the chrysalis stage it should be OK.
Best of luck! Hope you get a moth!
Sam
I’ve found a Ruby Tiger and I have no idea how old he/she is, or when he/she is going to start working on his/her cocoon, but I am feeding him/her dandelion. I keep him/her indoors in a room in an aquarium tank, with leaves to provide shade, and I clean out his/her cage every day. Is there any way to lower the chances of parasitic flies or is it just luck? This is my first attempt and the only thing I know is that my caterpillar is a Ruby Tiger.
Hi,
It really is just luck as to whether or not the caterpillar had avoided parasitoids before you picked it up – but now that it’s inside it’ll be safe from them. Sounds like you’ve got it all under control, good luck! Do post back and let me know how you get on 🙂
All the best
Sam
I think my caterpillar may be pupating. She is in a brown cocoon, I have given her new foliage and will leave her for a little while. Hopefully it will all go well!
Is it normal for her to be pupating in August?
Yep, they have two generations each year, so if all goes well your moth will be one of the “second brood”. According to UKMoths, second brood moths fly August-September time, so looks like it’s on schedule!
http://ukmoths.org.uk/show.php?bf=2064
Are you in the UK, just out of curiosity?
Yes, but unfortunately my moth seems to have been parasitised. The parasite is dead, but I’m not sure what it was. I have disposed of it.
I’m determined not to give up on raising a butterfly/moth and am looking for another caterpillar, hopefully another Ruby Tiger!
Pity about the parasitoid, but that’s the spirit, you’ll find a healthy one sooner or later! 🙂
Hi Sam,
I’m so pleased to have found your post, and to see that you’re still monitoring comments!
We brought what I think is a Ruby Tiger caterpillar in from my garden (munching on my chard!), and have set it up in a nice big mesh laundry container in our dining room with more chard and some black cherry tree leaves (I’ll go home and find some dandelion next). I’m worried about your note above, though, that Ruby will stay in a cocoon for the entire winter? I was picturing a moth in a couple of weeks… should I send my larva back out to the garden?
Thanks!
oops — I’m in Massachusetts, Northeastern US.
Hi 🙂
Good to hear from you! Since you’re across the ‘pond’, I don’t know whether your caterpillar will wait until spring to turn into a moth, or complete development and fly this autumn. I’d say at this stage it’ll proabably wait. You can still keep it, it would just require more patience! 🙂
In the short-term, if you are keeping it, keep it outside under cover. It will decide based on the temperature (as well as other factors, possibly) whether to pupate and emerge, or hibernate.
Let me know what happens! 😀
All the best
Sam
Hi there,
This post has been an amazing help, thank you for sharing.
I found one if these fluffy friends and last Friday found that he had spun into a cocoon. Thing is that today I’ve noticed two more little egg shaped things inside the cocoon – after reading this I’m fearing parasites? If it is parasites, what should I do? Any help would be appreciated, will check back later.
Rachel xx
Hi Rachel, thanks – glad you found it useful 🙂
You’re right, the egg-shaped things are the cocoons of parasitic wasps. The best thing is always to release wild things where you found them. Though I’d wait for the wasps to hatch and then release them, they’re pretty cool things to see themselves. Just watch you don’t get stung! 😉
Best wishes and a very happy Christmas.
Sam
Hi Sam,
Thank you so much for your reply. Well, the caterpillar actually arrived here in our Christmas tree. The container i housed him in is covered with some netting that I sneakily cut out of my window, all held together with hair pins – so it should contain the wasps safely. Will try and find out where the tree was from and see what can be done about releasing them back there. Felt quite sad that our furry friend didn’t make it, had no idea that caterpillars could have this sort of challenge! Bless them!
Thanks again, Rachel xx PS. Merry Christmas 🙂
How long on average do they live for? And what do the adults eat, if they eat anything at all? I found one a few days ago with a damaged wing, its fine other than that, so I took it in and want to try and give it a good rest of its life…
It’s always best to let the adults go – they need to be out there in the wild finding mates and making babies! They can fly pretty well with damaged wings. And they feed on nectar so if you have any good plants like dandelion or buddleia maybe put it there.
Hi thanks so much for the info, my little boy found a ruby moth caterpillar a few weeks ago in our garden we popped it into a insect pot and feed it, but we got some heavy rain so brought it inside, a few tissue and plant changes later we found it had spun a a cocoon, that was two week ago so am I right in assuming that in about a week we will have a moth and if so, what do I do how long do you keep them to dry off and do I put anything in there to feed it while it dries, also I checked and there doesn’t appear to be any egg shaped things in with him so fingers crossed, would parasites have shown themselves by now. We are in Devon and I read that the south moths are supposed to be prettier so we are very excited x
Hi Elizabeth,
Sorry for the delay! Glad to hear you’ve all enjoyed rearing the caterpillar. Fingers crossed it does ok! If it hasn’t emerged by the time you read this, put a twig upright in its container to give it something to climb up. Let it be for half a day when it does so (when its wings ae dry it’ll lay them tent-like over its back). Then enjoy its company for a while, get a few photos and let it go where you found it! 🙂
You do get some beauties “down there” 😀 look up Jersey Tiger!
Good luck!
Sam