You have to crawl before you learn to fly if you are a tussock moth.

Don’t have a hairy fit if you find one of these creepy, crawly, furry caterpillars. In the Island world of caterpillars, finding a tussock moth caterpillar should not ruin your day. At least, it isn’t a winter moth caterpillar and won’t be raining insect debris on your head during a jaunt in the woods or in your yard.

But tussock moth caterpillars can also be a pest as they, too, are considered defoliators or more accurately, defilers. The family name of tussock moths, Lymantriidae, means defiler.

Etymologically they are a good fit for the word caterpillar. The word, caterpillar, comes from the North French catapelose, a compound word meaning cat (from catta) and pelose (hairy), thus a hairy cat. Perhaps pelose changed into pillar from pillage describing the damage that caterpillars wreak on gardens and woodlands.

Tussock moth caterpillars are those alien-looking caterpillars wandering around this time of year. These cannot be missed or misidentified. This moth is reminiscent of an insect toothbrush, although the idea of putting one of these things in your mouth is somewhat repulsive.

The most common tussock we see is the white-marked tussock moth caterpillar. Look for a white-haired little beast with four yellowish backpacks, tufts or tussocks of hair on the top of their bodies and four long black pencil hairs from the front and back of the insect. The head is red and there are two additional reddish, orange dots on the aft section of the body.

Its bright colors warn of danger. This caterpillar would be tough to swallow for any bird and even humans should beware. Many folks have an allergic reaction to the hairs, especially, to those susceptible, around the eyes or on the skin. Handle with care, or not at all. This is a good case to look with your eyes and not with your hands.

In the literature, these caterpillars were referred to as catholic eaters, referring not to their religious affiliations or church-going status, but to their general food choices. They can eat almost any type of leaves of trees or shrubs. Tussock moth caterpillars are not picky at all.

Nor are they particular in the company that they keep. Their family, Lymantriidae, has a few bad seeds since members include the reviled gypsy moth caterpillars whose damage is as well-known as the aforementioned winter moths.

Tussock moths overwinter in woven cocoons that also contain those irritating hairs.

These can cause problems as well, when the cocoons are touched or the hairs blown about by wind. The moths that emerge are not very distinctive. They are small to medium, gray, nondescript furry moths. As most moths do, they fly at night. Tussock moths are short-lived and have undeveloped mouths, so do not eat.

The caterpillars will return as they have two generations per year. I say let them be. While tussock moth caterpillars may be considered a defiler, unlike the gypsy and winter moth caterpillars, they will only make your skin crawl if you touch them.

Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown.