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Woolly Bear Caterpillar

Summary: Banded woolly bears are the larvae of the Isabella tiger moth. It is fuzzy and harmless, unlike other hairy varieties.

The Isabella tiger moth's fuzzy looking caterpillars are known as banded woolly bears. Your kids have probably picked them up and played with them, but there is little to fear. They are harmless, unlike some other hairy species.

The woolly bear caterpillar has black bands on both ends of their body and red, orange, or brown centers. As superstition goes, if as woolly bear's black bands are long, the coming winter will have harsh weather. However, the length of their black coloration actually depends on the amount of moisture they receive.

Should you pick up the banded woolly bear it will curl up and play dead. The solitary banded woolly bear is usually seen scurrying about on its own, as it does not like to congregate with its fellow woolly bear cousins.

The banded woolly bear eats grass and different types of plants. It overwinters in stacks of firewood or underneath bark or logs. Like most other caterpillars, it forms a chrysalis to begin pupation and remains there for three or four weeks. Some woolly bears go through metamorphosis in the summer, while others overwinter and pupate in the spring.

The adult that emerges from the cocoon of the banded woolly bear is the Isabella tiger moth which as a wingspan of up to 2 ½ inches. Their wings are typically yellow or brown, with black spots. Female Isabella tiger moths lay their eggs on several different types of plants, including sunflowers and corn. Isabella tiger moths have a unique trait that other insects do not have. They can emit a sound to ward off their predators.


Woolly bears are a big deal in Vermilion, Ohio (a rural area west of Cleveland). The city dedicates an entire day of celebration to woolly bears at their annual Woolly Bear Festival. The small, one-stoplight town of Banner Elk, North Carolina also hosts a Woolly Worm Festival. They have a woolly worm race with over 1,400 racing caterpillars. The winner of the race is the banded woolly bear that will predict the severity of weather of the coming winter. Other woolly bear festivals include Beattyville, Kentucky every October and the Camargo, Illinois festival, complete with woolly worm races and reports from local meteorologists.

Many people enjoy raising banded woolly bears before they develop into moths. Here are some tips on how to do this. Before collecting the woolly bears, find an appropriate container to store them. A small plastic container with a lid should work just fine. Make sure to poke some holes into the lid for ventilation.

Add some soil into the container to allow the caterpillars to burrow. Feed the woolly bears crumbled pieces of leaves or other plants. They actually enjoy eating dandelions, so you will have a good use for your weeds. Make sure to add a small amount of water once every two weeks or so. Do not over-water the soil, though.

When fall comes around, the woolly bears will become slow moving. This is their cue for them to overwinter. If you want to raise them into moths, keep them in a cool environment, such as a garage or a basement.

To raise them as moths, you will need a place to store them. You can create an emergence cage for them to live in as they grow. Take some old window screens and cut them so that they are about 8 inches high. Find two used tuna cans (make sure that the edges are filed smooth so you do not cut your fingers. Make a cylinder with the screen and staple the ends together. Place one tuna can on the top and one on the bottom of the cylinder. Now you have your emergence cage.

Put about 2 inches of soil inside the cage, as well as plenty of leaf debris for the woolly bears to munch on. Put one or two woolly bears in the cage and watch them develop into Isabella tiger moths.

If you want to catch adult Isabella tiger moths, keep in mind that they are attracted to light in the nighttime. If you hang a white sheet or tablecloth over a clothesline outside and place a light source behind it, you may be able to attract the moths.


26 Mar 2012, 14:35
I'm thrilled that my wooly came out of hibernation the second day of spring! (I got it about 150 days ago) It then seemed to go back into hibernation. Will it suspend its cocoon like butterflies do? I have a couple of long sticks it will be able to use, if so.
01 Apr 2012, 13:50
I have a wooly bear and i've had him since Feb. he's making a cocoon i think but he's not moving very much and he's been making his cocoon for a few weeks is he okay?
07 Apr 2012, 16:30
So I have had a wooly bear since winter and today I woke up and he was in a cocoon so my sister came in my room and did know what it was so she ripped it open when I was in the shower. So when I went in my room I was really worried and I don't know what to do. Hes out of it and hes acting like a normal caterpillar but he has no hair. Will he make another cocoon?
26 Apr 2012, 20:03
my caterpillar has been in its cocoon for about two weeks and it hasnt hatched im wondering if its because its not in sunlight and im keeping it inside. Do Wooly Bear Caterpillars need sunlight to hatch from the cocoon?
27 Apr 2012, 09:32
Holly, I have a question for you. Did its cocoon suspend or did it lay on the bottom looking more like a clump of gray dog hair? I ask this because that is what mine has done and I'm worried that it may be decomposing. It's been two weeks.
Good luck with your moth!
30 Apr 2012, 09:01
Warmth helps as far as I know. but direct sunlight probably isn't the best. Two weeks is the norm I believe so it should be any time now!
Is your cocoon suspended? Mine is on the floor of a container looking like a clump of dog hair. It has been two weeks.
Not looking good. (insert sad face here)
05 Jul 2012, 17:10
ok mine has been in its lump of dog hair for 2 months im so sad hes dead huh?
21 Aug 2012, 15:34
I've heard that some tiger moths have mites that live in their "left" ear. Is this the Isabella tiger moth?
02 Sep 2012, 23:54
Ss there a certain tempature this catterpillar should be kept at?
03 Sep 2012, 11:13
Once it goes into hibernation (you may think it is dead) keep it in a cool to cold place. Wait till spring then it is like magic when it starts moving about. If it is not in hibernation yet make sure it has lots to eat, like clover. Good luck. I will be on the hunt for my wooly.
The same thing happened to mine. It's sad I know.
16 Oct 2012, 10:01
My son found a woolly bear yesterday so i took it in the house and made it a "cage" in a fishtank, this morning when i went to check on it and touched it it didnt "play dead" it didnt really move at all it dont seem to be moving but its not stiff or anything like thats...Is it dead?
20 Oct 2012, 16:57
My son and I found a woolly Bear today on the bike trail. It's October 20th. What do I need to keep him until he turns into a moth? Will he hibernate soon? Right now he's in a glass jar, with clover, grass, dandelion, leaves and a stick. He is munching away. Should I put soil in the jar with the leaves and grass and spray with water? I'm keeping him outside on a covered porch.
04 Nov 2012, 17:25
Who is ask the exterminator and btw,no such thiung as mother nature.
19 Nov 2012, 20:39
I have a question. I found a wolly catipillar and it was skinney so i took care of it now i don't know what to do with it? It's not even hatched yet?
Collin Blair
30 Nov 2012, 17:03
I'm trying to find a Wooly Caterpillar for a film shoot in Los Angeles. Does anyone have any leads? I know they're out of season here. Any help would be much appreciated. Thank!
susan compton
07 Jan 2013, 08:16
I just found a wooly caterpillar this morning. How much is it worth to you Collin :)
Collin Blair
07 Jan 2013, 12:49
Thanks for contacting, Susan. Where is the caterpillar now? Was it hibernating when you found it?
Jeff Sandoz
17 Mar 2013, 14:03
What are the natural enemies of the Wooly Caterpillar? How does it fend these off by sound?
Joanne Bedard
23 Mar 2013, 18:39
Just wanted to know, I live in Ottawa Canada, it's March 23, cold, and we have lots of snow, for the first time ever, I just found what I just found out is a Wooly Caterpillar. Now I've seen them in the fall before, and yes they do predict the winter, but never found one this early in the spring, and he was just walking across my path I brought him in and put him in a jar with celeri leaves and a few twigs...just wondering if this is a rare occurence or not...thanks!!
Jaime Leisure
02 Apr 2013, 20:06
@ Joanne
I live in Alaska and I also found a wolly caterpillar late March. found mine on the 30th, I brought him in and gave him some romaine lettuce and this morning woke to find him spinning his chrysalis!
22 May 2013, 01:47
I was googled to this page because I was looking for the recommended extermination process for these caterpillars, not how to love, house, raise, or where to find them. John if you found the expert let me know.
12 Sep 2013, 11:11
if the cocoons dont hatch after 3 to four weeks with spotted tussock (wooly caterpillar) then maybe try and freeze it for a few day to make it think its gone through winter, it wont die by freezing it has a antifreeze that will allow it to withstand -6c to -8c
24 Oct 2013, 21:11
My catapillar got lost in the house when I acsidently threw him..... his name was Leo.... never got to see the 3 day home with me. Do they eat fabric because mom is going to flip if they do...... Im sad.
24 Oct 2013, 21:18
How come their face looks like their butt? @Lucy good question I know they eat it when they grow up and stuff but not really catapillars just greens right?????????
29 Dec 2013, 14:19
I live in Michigan. I came across two Wolly Caterpillars today. They were located about 15 miles from each other. One in Holly and the other Flint. Yesterday the temp was 46 and today it's 36. We're just getting over a ice storm where the temps were well below freezing. Is it normal to see these caterpillars in December in michigan?
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