The woolly bear caterpillar in Texas finds exceptionally favorable climates in East and Southeast Texas. Spring 2024 has followed climatic conditions that have resulted in a significant population increase in these black fuzzy caterpillars. 

They are also known as the banded woolly bear, black fuzzy caterpillar, fuzzy caterpillar, fuzzy bear, hedgehog caterpillar, salt marsh caterpillar, and woolly worm. The woolly bear caterpillar can survive freezing temperatures. 

It can freeze solid during winter and then thaw in the spring without internal injury, and it continues through its life cycle. These caterpillars have tissues that contain a cryoprotectant to protect their soft bodies from freezing damage. This protectant allows them to repeatedly freeze and thaw while growing. 

The most common two species of woolly bear caterpillars found in Texas are the saltmarsh caterpillar and the garden tiger moth caterpillar. We call several species of caterpillars “woolly bears” that are densely covered in setae, which are their woolly part. There are over 260 species of them in North America. 

Each species has various colors and becomes a different species of moth. The saltmarsh caterpillar ranges in color from black to brown/rusty brown to yellowish. The garden tiger moth caterpillar sports a fuzzy black back and a brown belly. They may have bands of colors wrapping around their bodies. They live in Texas year-round. 

What Do the Black Fuzzy Caterpillars in Texas Turn Into?

In late spring, the garden tiger moth caterpillar turns into an Isabella tiger moth. Saltmarsh caterpillars develop into tiger moths and prefer salt grass for food. Tiger caterpillars have a more diverse diet. Woolly bear caterpillars have four life stages, which typically lasts six months.

Woolly bears lay eggs in clusters on host plants in the fall. Adults can lay up to 1,200 eggs per season, and they come out twice a year. The eggs hatch in five to 12 days. The hatchling is the caterpillar and in its larva stage for about six weeks. They molt several times in their larval stage. In late spring, they cocoon for their pupa stage. 

Woolly Bear Caterpillar Folklore

Several old wives’ tales promote that woolly bears are winter weather predictors. The colors of bands on woolly bear bodies can predict a harsh or a mild winter dates back to the U.S. Colonial days. A narrow rusty brown band predicts a cold winter, and a wide rusty brown band predicts a mild winter. 

If a woolly bear has thick hair, it suggests a harsh winter. Thinner hair implies a mild winter. Also, if a woolly bear is traveling north, you can expect a mild winter, and if south, you can anticipate a harsh one. But is there a scientific explanation for woolly bear folklore?

This belief became even more widespread in North America after Dr. Howard C. Curran, an influential entomologist known for his work with insects and curator of entomology at the American Museum of Natural History, informally studied them. Dr. Curran attempted to correlate the colors on the bands of a caterpillar with winter weather.

Dr. Curran, his wife, and his colleagues with their wives traveled to Bear Mountain, just north of New York City, from the late 1940s to the early 1950s. They measured the width of woolly bear bands in the fall, trying to come up with a scientific explanation. 

Each fall, Curran’s group collected woolly bear caterpillars, measured their black and brown bands, and compared their findings to the next winter’s weather. Dr. Curran’s study did not follow modern rigorous scientific methods. 

Dr. Curran’s work with woolly bear caterpillars catapulted scientific inquiry into public interest and popularized the woolly bear as an icon. He took reporters on his woolly bear expeditions and published his findings in the New York Herald Tribune and the national press picked up the stories. Each year. Each year, Vermillion, Ohio, hosts two Woolly bear Festivals. 

The notion that woolly bear caterpillars can predict winter weather is a delightful bit of folklore, but only a whimsical seasonal tradition. Their band colors are not a scientifically accurate method of winter weather prediction. The variations in the caterpillar’s band colors are due to biological and environmental causes.

Black Fuzzy Caterpillar FAQ

Are the Black Fuzzy Caterpillars in Texas Poisonous?

Fuzzy caterpillars in Texas are not poisonous. The prevailing advice is that if you are not 100% sure what an insect is, do not to touch it with your bare hands. You can always wear gloves if you have an overwhelming desire to pick up an unknown bug. 

Is it Safe to Touch a Black Fuzzy Caterpillar?

Black caterpillars in Texas with fuzzy bodies are not stinging caterpillars. You can handle them, and they will not hurt you. A typical banded woolly bear has 13 segments and is covered in setae or woolly hairs.  

How Do Woolly Bears Spin Their Cocoons?

Woolly bears caterpillars cocoon after feeding and molting for the last time in late spring. Woolly bear search for a safe and secure place to spin their cocoon. This could be in leaf litter, on a leaf, under bark, or in other sheltered spots. It produces silk from glands on their lower lips called spinnerets. 

The caterpillar begins to secrete silk and moves its head in a figure-eight sequence and spin silk fibers that stick to their leaves, etc. First, it forms a loose cocoon of silk threads. The caterpillar works outside to inside and adds layers of silk to build a more protective outer layer.

After forming its outer structure, the caterpillar continues to spin silk that thickens the walls of the cocoon, which insulates and protects it. The caterpillar moves its body to distribute the silk evenly. The caterpillar physiologically changes, and develops into the pupal stage. 

It does not eat and remains dormant while it metamorphoses into a moth. The caterpillar can spin its cocoon in a few hours or a few days. This depends on the environment and the caterpillar. This pupal stage can take several weeks, and the time depends on temperature and other environmental factors. 

The silk of the cocoon is strong and flexible and provides protection from predators and harsh environmental conditions. The cocoon often camouflages itself to blend in with the surroundings, which also helps to protect the pupa from predators. 

Kendall Davis
Author: Kendall Davis

Author: Kendall Davis Company: Lumini Services Kendall currently lives on the shores of Lake Texoma in Texas. She traveled across two-thirds of the U.S. for many years camping at lakes, rivers, and three oceans before motels and hotels if at all possible, and she continuously saw God's presence in nature. Writing for Lakehub allows Kendall to share her experience with God's creations.

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