Things with Wings: Butterflies at Wayland Community Gardens

Saturday, September 27, 2014

Butterflies at Wayland Community Gardens

I stayed close to home and checked out what was flying at the Wayland Community Gardens. At first, I saw only Cabbage Whites and Clouded and Orange Sulphurs. As I walked deeper into the gardens, I ran into Marjorie from the Mass Butterfly Club and together we searched for the wooly aphids that had been seen near the pit toilet! We had no luck and had just said good-bye when I heard Marjorie shout that she had found them! I hurried to join her, and together we carefully pulled the branch down and examined the wooly aphids for caterpillars. We found none.

Soon, I found another branch with more wooly aphids and we repeated our careful examination and found one caterpillar on this branch! Victory! This is the only known butterfly caterpillar that is carnivorous, feeding on wooly aphids rather than plant material. It was pretty exciting to find as neither of us had ever seen one before! Eventually, it will turn into a beautiful Harvester butterfly.

You can see there are lots of ants around the wooly aphids. Ants are in a mutualistic relationship with the aphids, protecting them from predators and eating the honeydew they excrete. After reading that, though, I wondered why the ants didn't attack the Harvester caterpillar. I later learned that the exoskeleton of the Harvester caterpillar is similar to the cuticle of an aphid, so the ants may "smell" aphid when in reality it's a Harvester caterpillar. Chemical camouflage!

We were just leaving the wooly aphids when I saw a flash of orange fly by which I thought may have been a Pearl Crescent. I lost sight of it, but Marjorie found a Bronze Copper on a bloom of Goldenrod that must have been what I had seen in flight. It was fresh and beautiful! Within seconds, we spotted two more as well as an Eastern Tailed Blue. Suddenly things were picking up!