SEPTEMBER
1999

 

 

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

 

 

 

 

9-23-99

Is Fuzzy Wuzzy a Bear or a Worm?

Remember the kid's rhyme about Fuzzy Wuzzy? Fuzzy Wuzzy, it seems, was a bear. According to the ditty, Fuzzy Wuzzy had no hair! The obvious question then, and the appropriate concluding line, is “Fuzzy Wuzzy wasn't fuzzy, was he?"

To most of us, fuzzy wuzzy is very descriptive of some caterpillars. These hirsute-a fancy word for hairy-immatures of moths probably are responsible for the name caterpillar.

Ancient Romans noticed the fuzzy creatures slinking along the ground. They used the descriptive Latin term catta pilosa , or hairy cat, for these animals. The English word, based on that Latin name, is caterpillar.

Hairy caterpillars are common insects. So common, in fact, that most people have noticed them at one time or another-especially during the fall. By this time, most have completed their feeding. The fuzzy caterpillars are searching for a place to spend the winter. Some survive winter as caterpillars. Others change into the pupal form for the long winter nap.

Many of fuzzy caterpillars turn into moths called tiger moths. The name is based on the fact that many of the moths have conspicuous strips or spots. Many of them have black and orange color patterns. One of the common moths of this group is called the great leopard moth. It is a white moth with brown spots. Another white moth with spots has larvae known as salt marsh caterpillars.

Probably the best known of these hairy caterpillars is the one known as the banded woolly worm. This woolly worm is the one with a reddish-brown band around the middle. Both ends of the caterpillar are black. The adult of this caterpillar is known as the isabella moth.

These caterpillars are widely held to be predictors of the severity of the upcoming winter. For instance, the width of the brown band on the banded woolly worm is used as a winter indicator. Wider brown bands are said to indicate milder winters. This means that the blacker the woolly worm has the harsher the winter will be. Of course, all black woolly worms indicate severe winters.

Like all good folklore, there is more than one version of each bit of lore. This is true of woolly worms and winter. Some say that the density of the woolly worm's coat will indicate winter severity. So, if the woolly worms are very woolly, it will be a cold winter. The worms are just wearing a heavy coat in anticipation of the winter cold. 

The direction of travel of the worms also is said to foretell impending winter conditions. Worms crawling in a southerly direction are trying to escape the cold winter conditions of the north. On the other hand, worms crawling on a northward path would indicate a mild winter.

Of course, these insects cannot predict the winter. The differences in the width of the band on the banded woolly worm are a result of genetics. In other instances, the density of the hair covering or the color of different worms might reflect that different species are involved. There are some 200 species of tiger moths in North America, and each species has slightly different color patterns and hair coverings.

In fact, the density of the hair covering might be important for the woolly worms' winter survival. It is a protective coat, and it might offer some protection from the winter cold in a hibernating worm. The hair is also used to help cover the pupal case in those worms that pupate before the beginning of winter. A heavy coat on woolly worms very well might represent survival of countless ancestors in past winters.

The coats must have protected woolly worms well in central Indiana last winter, since this past summer brought high populations of the fuzzy creatures-probably a result of successful overwintering and a good survival rate this summer. Population ecologists classify woolly bear caterpillars as insects that exhibit “sporadic outbreaks of high population density." In other words, in many years we don't see many of the fuzzy worms and then they are everywhere.

While this year might be a good one for people who bank on the woolly worms to predict the winter, it wasn't so good for gardeners. Few people who found the fuzzy caterpillars on their plants probably noted “how fuzzy was he" before smashing the offending caterpillar to bits!

 

Writer: Tom Turpin
Editor: Olivia Maddox