Woolly bear caterpillars, the larvae form of the tiger moth, are a well-known sign of fall in North America. These charmingly fluffy caterpillars are easy to care for at home, whether you’re raising them into adults as an educational project for children or you simply love these insects. We spoke with entomologist Dr. Samuel Ramsey to learn how to give your woolly bear a proper habitat, what to feed them, and how to care for them as they transform into a moth. Read on to find out more!
Raising Woolly Bear Caterpillars
Place the woolly bear caterpillar in a container with air holes and add some leaves and twigs. Woolly bears like to eat low-growing herbaceous plants, so feed them dandelions, plantain weeds, dock, or clover. Feed them fresh food every day and keep their container outside until they build a cocoon.
Steps
Setting Up a Habitat for Your Caterpillar
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Get out a container with a lid and add air holes. Woolly bear caterpillars are safe to keep in a clear glass or plastic container , like a mason jar, or a cardboard box. Just make sure the container has a jar lid to prevent the caterpillar from escaping. Then, punch holes in the lid so the caterpillar can breathe. [1] X Research source
- Alternatively, use a mesh lid. It's just important that the lid allows for some air circulation.
- Only keep 1 to 2 woolly bear caterpillars in the same container at a time. Dr. Ramsey says “it's important that you don't end up with a cage so full of woolly bears that everybody is not getting enough food because…they don't like to have to compete for resources.” [2]
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Expert Source
Samuel Ramsey, PhD
Entomologist Expert Interview. 20 January 2021.
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Place twigs and leaves inside the container. Your caterpillar needs places where they feel safe to hide, sleep, and eventually hibernate and build a cocoon. Cover the bottom of the container with leaves and plant debris. Then, find a few small twigs or branches outside and place them in the jar. [3] X Research source
- Angle the branches diagonally, as this allows the caterpillar to climb onto it when it's ready to build its cocoon.
- Adding twigs and leaves helps mimic the woolly bear caterpillar’s natural habitat. They live in moist fields, meadows, and forests.
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Remove droppings in the container every day. Each day, look for droppings (called frass) in the container. Simply scoop up the caterpillar with a twig or leaf and place it in a different jar as you clean. Then, use a tissue or paper towel to wipe up the droppings. Just add the caterpillar back to the container when you’re done. [4] X Research source
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Keep the container outside in a sheltered spot. Woolly bear caterpillars need to feel the outside temperatures to know when to hibernate and build a cocoon. Set the container in a secure location outdoors, like on your patio, screened-in porch, garage, or a shed near your house. [5] X Research source
Feeding Your Caterpillar
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Provide plants from where you found your caterpillar. The easiest way to feed your woolly bear caterpillar is to give it leaves from the host plant you found it munching on. Simply remove some of the leaves and plants from where you found your caterpillar . Then, place them in the caterpillar's container.
- For example, if you found your caterpillar on a maple tree in your yard, remove some leaves and put them in your caterpillar's home.
- Tiger moths (the adult form of the woolly bear caterpillar) lay their eggs on leaves, weeds, and grasses, which are called host plants. When the eggs hatch, the larvae start eating. [6] X Research source
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Feed the caterpillar dandelions, clover, or grass if it wasn’t near plants. If you didn’t find the caterpillar on its host plant or near other plants, that’s okay—woolly bears are herbivores that like to eat a wide variety of plants. They tend to prefer low-growing, seed-bearing plants like dandelions, plantain weeds, dock, burdock, aster, nettle, goldenrod, clover, and sunflowers. They also munch on grasses, herbs, and leafy greens like spinach and cabbage. [7] X Research source
- Woolly bear caterpillars also eat some tree leaves. Dr. Ramsey says they usually like to eat “maple leaves and birch leaves
.” [8]
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Expert Source
Samuel Ramsey, PhD
Entomologist Expert Interview. 20 January 2021.
- Woolly bear caterpillars also eat some tree leaves. Dr. Ramsey says they usually like to eat “maple leaves and birch leaves
.” [8]
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Expert Source
Samuel Ramsey, PhD
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Give your woolly bear fresh food every day. Woolly bear caterpillars need a constant supply of food until they hibernate and build their cocoon. Ensure your caterpillar has a fresh supply of leaves, weeds, and grasses each day. If you already fed your woolly bear for the day but they’re out of food, give them another helping. [9] X Research source
- Dr. Ramsey says to “make sure to replace the leaves when they start to become crunchy” because “woolly bears will only eat them while they are still soft.” [10]
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Expert Source
Samuel Ramsey, PhD
Entomologist Expert Interview. 20 January 2021.
- Dr. Ramsey says to “make sure to replace the leaves when they start to become crunchy” because “woolly bears will only eat them while they are still soft.” [10]
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Expert Source
Samuel Ramsey, PhD
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Mist the jar or container with water regularly. Woolly bear caterpillars get most of their water from plants. However, small droplets of water can help your caterpillar stay hydrated. Each day, use a spray bottle to mist the bottom of the container. [11] X Research source
- Woolly bear caterpillars do not need a water container to stay hydrated. Plus, they can actually be a drowning hazard
Caring for Your Caterpillar as it Transforms
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Give your caterpillar food when it hibernates and after it wakes up. In the winter, woolly caterpillars go into hibernation to protect themselves from the cold temperatures. However, they may wake up from time to time and need to eat. Once they’re done hibernating in the spring, they’ll also need food to prepare for their transformation. [12] X Research source
- Check on your caterpillar regularly to see if it’s awake. Then, give it fresh leaves, weeds, or grass.
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Move the container indoors when your caterpillar builds its cocoon. In the spring, your caterpillar will rest on some leaves or a branch and stop moving. Then, it will start to spin a cocoon around itself. Once the caterpillar is fully inside the cocoon, it is safe to bring it inside. [13] X Research source
- This can also help you better observe the cocoon and watch for signs that the moth is emerging.
- When the woolly bear caterpillar spins its cocoon around itself, it’s called a pupa. During the pupa stage, it goes through metamorphosis and turns into a moth. [14] X Research source
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Feed the moth nectar when it emerges from the cocoon. After 1 to 3 weeks, a tiger moth will start to break out of the woolly bear’s cocoon. When you notice signs that it’s emerging, add a few fresh flowers to the container. Unlike the caterpillars, tiger moths only drink nectar. [15] X Research source
- Add a few extra twigs to the container to give the newly emerged moth something to perch on and dry its wings.
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Release the moth after a few hours to 1 day. Once the woolly bear caterpillar transforms into a tiger moth, Dr. Ramsey says “it's best to simply let them go.” You can keep your moth in the container for a few hours after it emerges to observe its new form and watch it eat. Then, release the moth outdoors near where you found it as a caterpillar. [16] X Expert Source Samuel Ramsey, PhD
Entomologist Expert Interview. 20 January 2021.- Dr. Ramsey says “it is very difficult for you to raise an adult moth,” as they can’t comfortably live in a container like a caterpillar can. [17]
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Expert Source
Samuel Ramsey, PhD
Entomologist Expert Interview. 20 January 2021. - Plus, your moth belongs in the wild. It needs to reproduce and lay eggs that hatch into new woolly bear caterpillars.
- Dr. Ramsey says “it is very difficult for you to raise an adult moth,” as they can’t comfortably live in a container like a caterpillar can. [17]
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Expert Source
Samuel Ramsey, PhD
Expert Q&A
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QuestionWhat do woolly bear caterpillars like to eat?Dr. Samuel Ramsey is an Entomologist and a researcher with the United States Department of Agriculture. Dr. Ramsey has extensive knowledge of symbiosis and specializes in insect disease spread, parasite behavior, mutualism development, biological control, invasive species ecology, pollinator health, and insect pest control. He holds a Bachelor’s degree in Entomology from Cornell University and a Ph.D. in Entomology from the University of Maryland. Dr. Ramsey’s research on bees has enabled researchers to develop targeted control techniques to restore honey bee populations worldwide. He also hosts a YouTube series called “Dr. Buggs.”Caterpillars have taste buds, and a lot of different kinds of caterpillars will only eat certain kinds of leaves. If you don't have the right kinds of leaves, the woolly bears will not eat them. They prefer dandelion leaves. If you see the dandelions growing out of the ground, if you take some of the leaves off of them and put them into the woolly bear enclosures, they will consume those. They do like maple leaves and birch leaves. Those are good for them but there are more leaves that they will not eat than they will. So, it's important to find the right ones because they are picky eaters.
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QuestionCan I keep multiple woolly bear caterpillars in the same enclosure?Dr. Samuel Ramsey is an Entomologist and a researcher with the United States Department of Agriculture. Dr. Ramsey has extensive knowledge of symbiosis and specializes in insect disease spread, parasite behavior, mutualism development, biological control, invasive species ecology, pollinator health, and insect pest control. He holds a Bachelor’s degree in Entomology from Cornell University and a Ph.D. in Entomology from the University of Maryland. Dr. Ramsey’s research on bees has enabled researchers to develop targeted control techniques to restore honey bee populations worldwide. He also hosts a YouTube series called “Dr. Buggs.”As woolly bears begin to grow, they can be a bit gregarious. Having friends around can be fun for the woolly bears. You can raise a bunch of them together but it's important that you don't end up with a cage so full of woolly bears that everybody is not getting enough food because they do like to crowd each other out. They don't like to have to compete for resources.
Reader Videos
Share a quick video tip and help bring articles to life with your friendly advice. Your insights could make a real difference and help millions of people!
Tips
- According to folklore, woolly bear caterpillars can predict how severe the winter is going to be. The longer their front and rear black bands are, the more severe the weather is going to be. However, there’s no scientific evidence that woolly bears actually predict the weather. [20] X Research sourceThanks
- The woolly bear caterpillar’s bands do grow longer and shorter, though. Older and better-fed caterpillars tend to have a shorter red-orange band in the middle. [21] X Research source Wetter weather also tends to result in caterpillars with longer black bands. [22] X Research sourceThanks
- Woolly bear caterpillars are named after the fuzzy-looking hairs that grow along their body and the fact that they hibernate.Thanks
Tips from our Readers
- If you have siblings, make sure to put your woolly bear caterpillar in a safe spot that's not easily accessible to them.
- You can also use a small aquarium tank or a fish bowl to take care of woolly bear caterpillars.
- If possible, change their food everyday so they don't eat any rotting food.
- You can also add moss to the bottom of the cage instead of grass.
Warnings
- Woolly bear caterpillars are not dangerous and are generally safe to handle—they do not sting or inject venom. However, to some people, their hair may be irritating and cause dermatitis. [23] X Research source This is typically easily treated with an anti-itch cream or moisturizer. If your symptoms get worse or you’re in pain, contact your doctor for treatment. [24] X Trustworthy Source Mayo Clinic Educational website from one of the world's leading hospitals Go to sourceThanks
- Don't touch the newly hatched moths, as their wings could be damaged. If they are damaged, they could easily die or become crippled.Thanks
References
- ↑ https://content.ces.ncsu.edu/banded-woollybear
- ↑ Samuel Ramsey, PhD. Entomologist. Expert Interview. 20 January 2021.
- ↑ https://www.cambridgebutterfly.com/going-bear-hunting/
- ↑ https://www.cambridgebutterfly.com/going-bear-hunting/
- ↑ https://content.ces.ncsu.edu/banded-woollybear
- ↑ https://content.ces.ncsu.edu/banded-woollybear
- ↑ https://content.ces.ncsu.edu/banded-woollybear
- ↑ Samuel Ramsey, PhD. Entomologist. Expert Interview. 20 January 2021.
- ↑ https://content.ces.ncsu.edu/banded-woollybear
- ↑ Samuel Ramsey, PhD. Entomologist. Expert Interview. 20 January 2021.
- ↑ https://www.cambridgebutterfly.com/going-bear-hunting/
- ↑ https://yardandgarden.extension.iastate.edu/encyclopedia/woollybear-caterpillar
- ↑ https://www.cambridgebutterfly.com/wp-content/uploads/2019/09/Care-for-Bears-Brochure-2019-web.pdf
- ↑ ​​ https://www.dnr.state.mn.us/mcvmagazine/issues/2024/sep-oct/profile.html
- ↑ https://www.dnr.state.mn.us/mcvmagazine/issues/2024/sep-oct/profile.html
- ↑ Samuel Ramsey, PhD. Entomologist. Expert Interview. 20 January 2021.
- ↑ Samuel Ramsey, PhD. Entomologist. Expert Interview. 20 January 2021.
- ↑ https://mdc.mo.gov/discover-nature/field-guide/isabella-tiger-moth-woolly-bear-woolly-worm
- ↑ https://yardandgarden.extension.iastate.edu/encyclopedia/woollybear-caterpillar
- ↑ https://www.weather.gov/arx/woollybear
- ↑ https://www.weather.gov/arx/woollybear
- ↑ https://mdc.mo.gov/discover-nature/field-guide/isabella-tiger-moth-woolly-bear-woolly-worm
- ↑ https://mdc.mo.gov/discover-nature/field-guide/isabella-tiger-moth-woolly-bear-woolly-worm
- ↑ https://www.mayoclinic.org/diseases-conditions/dermatitis-eczema/symptoms-causes/syc-20352380
About This Article
To care for a woolly bear caterpillar, keep it in a sealable container that has holes in the lid for air circulation. You should also put an upright twig in the container so your caterpillar has something to make a cocoon on. Since woolly bear caterpillars need to be in the cold to survive, keep the container somewhere outdoors. To feed your caterpillar, put plants, leaves, flowers, and grasses from the area where you found it into the container. Also, mist the inside of the container with water every day so your caterpillar stays hydrated. To learn how to release a woolly bear caterpillar after it emerges as a moth, scroll down!
Reader Success Stories
- "I found a frozen woolly bear on our deck near the sliding door and we are having freezing temps out now so I brought it in and put it in a medium size fish bowl with twigs and several dried leaves. A few hours after I did this I found it clinging to a branch! The lid is a container cover that stretches to a tight fit, I poked several holes in it and mist it daily. Seems pretty happy!" ..." more