Welcome back to Ask a Naturalist: your own personal “Google” for information on all things natural on PEI. Judging by the more than 50 questions I’ve gotten over the past two weeks, this is the most famous insect on PEI right now. Meet the Hickory Tussock Moth Caterpillar (Lophocampa caryae).
There’s been some information floating around that’s only partially true and has some people needlessly concerned about this caterpillar. First, it isn’t new. Hickory Tussock Moths are common and native to Canada and have been known from the mainland for well over a decade (and have likely been there far longer). The first confirmed PEI records were just last year, though it was almost certainly here well before this – the fact that it’s being found in all three counties supports that. Our invertebrates are just not very well documented.
Next, it’s not venomous, poisonous, or particularly dangerous for most people. For years, there have been annual click-bait headlines throughout Hickory Tussock Moth territory with warnings ranging from slightly exaggerated to over-the-top. Hickory Tussock Moth caterpillars do have hairs that can irritate the skin but – while reactions will vary from person to person – for most of us they are very mild.
I looked for documented cases of severe reactions to encounters with Hickory Tussock Moth caterpillars. The most extreme was a 14-month-old child who ingested a Hickory Tussock Moth cocoon and required hospitalization, but ‘recovered uneventfully’ according to the report. A review of hundreds of reports of Hickory Tussock Moth caterpillar exposures called in to regional poison control centres found that the vast majority were treated at home and resolved within 24 hours. A small number of cases where the caterpillar had contacted the inside of a child’s mouth or eyes required medical treatment, but there were no serious complications.
PEI has several species of caterpillars with hairs that can cause irritation, and it’s a good practice to avoid touching any fuzzy caterpillar. Like the situation above, there is a documented case of an 18-month-old child that ingested a Spotted Tussock Moth caterpillar (Lophocampa maculata, a common native species here) and required hospitalization to resolve the issue. The literature is full of reports of reactions to caterpillars other than Hickory Tussock moth; there is no need to single it out.
While the information currently circulating on social media is mostly false, it does have some useful advice. If you’ve had contact with a fuzzy caterpillar resulting in irritation, use tape and/or tweezers to remove the hairs, wash the area, apply ice, and take an antihistamine and/or apply a topical steroid cream if needed. Contact with eyes or the inside of the mouth may merit a visit to a health care provider.
The bottom line is that seriously adverse reactions to Hickory Tussock Moth (and other) caterpillars are extremely rare, ranking well below bee stings, spider bites, pet dander, shellfish, peanuts, and a host of other things. There is no need to fear or persecute them. It’s been a great growing season, and many local species of caterpillars are feeding up and preparing to overwinter. They’ll soon be gone – until this time next year!
If you have a question about PEI’s wild side, it’s likely others do too. Follow me here or on Facebook, join the conversation, and Ask a Naturalist about PEI untamed!
Comments