Instar

As a caterpillar develops, it outgrows its skin.  Each stage between moltings of its skin is called an instar.  This is “Junior” entering his second instar.  Well, actually I’m not exactly sure in which instar he is.  This just happens to be the first time I’ve seen the shed skin which he subsequently ate after I took this photo.  It is quite possible that he has already done this once before.  After doing some reading, I learned that caterpillars eat their skin to hide evidence of themselves from predators.  

This isn’t the greatest quality photo, but I had to share it.  Hard to believe that he fit in that tiny discarded skin!

After he had rested for a few hours, I held his wilting leaf next to the edge of a fresh leaf, allowing him to move to the new leaf on his own.  Caterpillars are quite fragile after molting, so I did not want to cause injury by handling him.

Eastern Tiger Swallowtail (Papilio glaucus)

This caterpillar is still quite small, but it has been fun watching him grow a little each day.