Invasive browntail moth caterpillars in Maine are getting killed off by fungi and viruses

BANGOR DAILY NEWS • June 7, 2026

Browntail moth caterpillars, the invasive insects carrying rash-causing hairs, are continuing to die off across Maine. A state monitoring program with sites in Bangor, Bridgton, Newport and Turner has found visible differences in development among caterpillars at the same sites within the last month, a trend similar to last year. That can be a sign of parasitism or infection by pathogens. The caterpillars affected more than 150,000 recorded acres across Maine at their 2022 peak.