Is it fair to forsake a whole category of creature?

The National Capital Poison Center insists that “avoiding caterpillars is best” but it is simply not in my nature to demonize such fascinating fauna so I cannot abide by this advice. Caterpillars are amazing, colorful, dull, hairy, furry, smooth, long, short, slow, fast... they are all things but clearly not for all people. 

Perhaps I shouldn’t be so cavalier. There are places and species that do warrant warnings. There is a caterpillar in South America, lonomia obligua, that can be deadly. In fact, encounters with these caterpillars kill more people than comparable run-ins with snakes. Between 1989 and 2001, there were 21 deaths in Brazil attributed to this insect whose venom is an anti-coagulant, causing human blood not to clot. Victims can hemorrhage to death in the most extreme cases.  

With a little caution, and depending on where you live and with which caterpillars you share habitat, most can of us can enjoy these species even if only with your eyes. It is the spines, spikes and hairs of some caterpillars that can be a problem, filled with venom, stinging cells, or other irritants, so look but do not touch and you will be safe.  

If you inadvertently come into contact with one of the irritating types, take this advice for relief: remove the spines or hairs from your skin (tape is suggested) then apply ice and baking soda to reduce the itching and burning that can occur in some folks with sensitive skin. Hydrocortisone can also help.  

A local venomous species has my attention this week though the animal that I saw was the adult and not a more irksome larval form. The spiny oak slug, euclea delphinii, is a colorful, spiky and uniquely slug-shaped caterpillar that I would love to see. Alas, it was the moth version that was observed and photographed in Chilmark last week.    

The moth version is also adorable. It appears as a brown and green furry beast that has been described as “chocolate colored and minty green.” That green color brings to mind Breyer’s mint chocolate chip ice cream, avocados, or key limes. A funny choice of color for a moth that doesn’t want to get tasted! The green sections of the wings are more prominent in males, with the male moths being smaller than the females. 

Spiny oak slug moths are nocturnal and are often found in wooded areas. Like most moths, they are attracted to lights. As caterpillars, they are omnivores and opportunists, eating a variety of plants — including apple, ash, chestnut, basswood, cherry, beech, maple, oaks, blueberry, hackberry, hickory and others — and rarely doing much damage to the trees. Their other interesting food source is their own shed. Caterpillars will consume their skin after sloughing it off after a molt. Reuse, recycle and repeat. 

It is not advisable to eat either the caterpillar or moth. That cryptic color warns off predators – human or otherwise – with its pronounced pigments and poisons. If you do come into contact, note that the American Association of Poison Centers reports no fatalities in the United States caused by this or other caterpillars. 

That fact is good news if you get into an inadvertent slugfest with this species of appealing hues but unappetizing flavor. 

Suzan Bellincampi is islands director for Felix Neck Wildlife Sanctuary in Edgartown and the Nantucket Wildlife Sanctuaries. She is also the author of Martha’s Vineyard: A Field Guide to Island Nature and The Nature of Martha’s Vineyard.