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Species Page - Pyrrharctia isabella
Pyrrharctia isabella ->species page

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scientific name    Pyrrharctia isabella    

common name     Isabella Tiger

This species inhabits open parkland and prairie habitats.

Mid June to mid July.

The amount of black on the forewing is somewhat variable, but this species is fairly distinct with its yellow ground colour and black markings. Females have a pink tinge to the hindwing, whereas males have a yellow hindwing.

life history
No information available.

Although widespread, this species is usually not common.

diet info
Known to feed on a wide variety of plants, primarily herbs and forbs.

Widespread across the U.S. and southern Canada. It is likely at its northern range limit in the southern boreal forest of Alberta.

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Comments (10)Add New Comment

Linda M. Champagbe (2011-12-04)
Woolly Bear:
Saw one today in sun-warmth near 50 F. on driveway in December. In town of Greenfield,New York on wooded farm area, along rural road. Placed it off entry road and near tree base. In moving these from old farm porches, and open land, often put them in more vegetated area. What is best place to put them when moving from busy area. Have a great photo of one illuminated by rising sun rays as it walks along an old plank. Do I see a tiny tongue on its face, or is it just the sun hitting some 'hair' at the front of the lower face.
I have yet to see and photograph the moth. Is it a day flyer?
Was pleased to have this information you have provided.
Linda Champagne, writer/photographer
Niskayuna, New York

Gary Anweiler (2011-12-08)
Hello Linda. I appreciate your method for relocating the caterpillars that you encounter on your deck; much superior to the more common "stomp and remove? method!
These roaming "cats" are likely done feeding and are seeking a place to build their cocoon, so what you are doing sound fine. The caterpillars do not have tongues as such, rather a set of hard mandibles for processing vegetation, so perhaps it was these or a tuft of hairs that you saw, as you suggested. The moths are mainly nocturnal, and are sometimes encountered at or near lights that were on overnight.

Gary Anweiler

Solomon Zweig (2012-02-24)
Hi! I'm 7 years old, and I found 3 wooly bear caterpillars that I am keeping in a special cage from the pet store. I live in upstate New York. I keep a wet sponge in the cage, and give it fresh grass and leaves. One seems to have turned into a cocoon, one looks dead, and the third appeared on our doorstop the day the other one died. Am I doing the right thing? My Mommy is a Psychologist, but would like to be an entomologist in her next life! Thank You, Solomon

Felix Sperling (2012-02-25)
Hi Solomon (and Solomon's Mom),
I'll answer your question two ways. If you mean "doing the right thing?" as whether this is the best way to keep a cocoon so it will emerge to become a moth, then I suggest you should put the dead-looking one in the garden. If it really is dead, then that way if it goes moldy then it won't be a problem for the still-living cocoon. Also, you should put the cocoon in the cage outdoors or into your fridge so that it gets something closer to natural conditions. Like seeds, some insects need some cold in winter so they will develop properly. But the still-living caterpillar has probably finished eating and doesn't need more food, so you don't need to give it more, especially since it doesn't eat grass much, rather than a variety of herbs and shrubs.
But if you are asking whether it is ethically the right thing to put something in a cage (after all your Mommy is a psychologist!), I think it is a great idea to raise caterpillars so that you can see the mystery of "metamorphosis" up close yourself. You can release the moth that comes out, if you would like, or you can keep it to show other people how wonderfully cool insects really are.

Solomon Zweig (2012-03-01)
Thank You Felix!

Maddie (2014-02-01)
I am 8 years old. I found one of these caterpillars on my porch in North Alabama. I named him "Fuzzy." I would like to keep him in a clear container on my porch so that I can watch his metamorphosis. Would lettuce be a good food to put in his habitat? And what temperature would be too cold- so that I should bring him inside?

Gary Anweiler (2014-02-03)
Hi Maddie

Your caterpillar should be able to eat a wide variety of plants, including grass, almost any legume and leaves of various other plants, even lettuce (wash it and dry it first!). You can try several kinds of leaves and see what it likes. When it is ready to turn into a moth it will stop eating and wander around a bit and then spin a cocoon in which it will turn into a moth. Make sure what you feed it has not been sprayed with pesticides! Good luck with your caterrpillar !

Matilda (2014-10-20)
Hi, I found one of these on my back porch, named it Little Bear, and put it in a bug keeper. Are certain leaves poisonous to these caterpillars? Do you know if they'll eat them? Are clovers, salad leaves, dandelion leaves, or grass best for these caterpillars? Thanks for your time!

Jim (2016-10-05)
I live in the Seattle area on a wooded property and find these in the late summer and fall. I always pick them up and move them if they are in harms way or exposed to birds and spiders. The problem is I don't know where to put them; what kind of place do they need to either winter over or make their cocoon? I used to think they would be happy in my covered wood pile but they appear to not like that and will crawl back out, perhaps too dry? Is there any kind of artificial habitat I could build for them that they would like? Either they had a good year or my efforts to help them are working as I picked up 20 of them in close proximity and moved them this morning because they were on an area to be trimmed.

Sue Smith (2016-12-20)
About woolly bear caterpillars: Found a live woolly bear inside near a wreath made of dried hydrangeas from outside. It's been wintry here for quite awhile so I don't know how long it's been inside. Didn't want to throw it outside with the sub-zero temps we've been having, so asked around and was told to put it in a tallish (5-6") container with gardening coir so it could burrow and put it in the fridge until spring. Is that true?

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References (1)
Specimen Info
There are 62 specimens of this species in the online database
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Specimen List (62)
Related Links
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