On my road trip to Michigan, I visited Library Park in Elk
Rapids. The Park is on the shores of Lake Michigan, with a
beach, a harbor and a Jetty. At the end of the jetty were a few
clumps of beach grass, bushes and a short willow. Such a harsh
habitat does not teem with insect diversity, but an entomologist
can intensively search the few available resources. On the
willow, I found a single gypsy moth caterpillar. How did it
arrive? The willow was hundreds of meters from the nearest tree.
Gypsy moth females are flightless and lay eggs in clusters. It
is unlikely that a female gypsy moth laid a single egg on the
bush. The egg could have been part of a mass laid on a piece of
wood that drifted to the jetty.Possibly the caterpillar traveled
by air. Gypsy moth larvae can spin down from trees on silken
thread and catch a ride on the wind. If this happened, this
single larva was lucky enough to land on the only possible plant
that could support it before it was blown into the miles of the
watery death of nearby Lak