Our Executive Director found this critter on an apple tree near his home in northern Vermont on July 25. What is it?
Answer
A tiger swallowtail caterpillar (we accepted both eastern and Canadian).
The enlarged front and the smallish eyespots were a giveaway on this, though the brown color may have thrown some of you off. Yes, swallowtail caterpillars are typically green, and so was this one just hours before this picture was taken. The brown indicates that it has become pre-pupal and is searching for a place to build its chrysalis. Favored pupation sites are rock ledges and other out of the way places - in most cases, the earth tones provide the caterpillar some measure of camouflage.
To learn more about caterpillars and the butterflies and moths they become, check out our photo feature in the Summer 2010 issue: http://northernwoodlands.org/articles/article/transformations-which-caterpillar-becomes-which-butterfly/