We spotted this moth on a tree in Concord, New Hampshire. What species is it? What is it doing? And what’s with the dead caterpillars nearby?
Answer
This is a female spongy moth depositing eggs on the tree trunk. The dead caterpillars indicate the spread of disease and virus infection within the spongy moth population. “When these populations reach extreme levels, disease spreads easily, and spongy moth essentially experiences its own pandemic at the end of every outbreak cycle that ultimately returns it to endemic (normal background) population levels,” said Mike Parisio, a forest entomologist with the Maine Forest Service. “The dead vertical caterpillars were most likely killed by a fungal pathogen, Entomophaga maimaiga (‘Entomophaga’ translates along the lines of ‘insect eater’). The upside down ‘V for virus’ caterpillars were most likely killed by a viral pathogen.”
This week’s contest winner was Maddie Ryan