Butterflies in Winter
As I gazed out at the site for the Butterfly Ridge Butterfly Conservation Center gift shop and classroom (coming summer of 2016) the other day, I was looking out across a hillside with a fresh five inches of snow. And this thought crossed my mind, "How in the world does a butterfly survive this kind of weather?"
As unbelievable as it may seem, many of the butterflies that call Ohio home spend the winter here in Ohio, in one form or another. Not many of our butterflies immigrate in during the warmer weather. So how do they do it?
The swallowtails in our area overwinter as a chrysalis, hanging from the side of a tree or perennial flower stem, exposed to the brutal sub-freezing temperatures of winter. A week ago Butterfly Ridge experienced an overnight low of 3 degrees. The chrysalis survives because it is in a suspended state called diapause, sort of like hibernation but more extreme.
Our local fritillaries spend the winter as a caterpillar. The early instar caterpillar wedges himself into a deep crack in a tree's bark and holes-up there for the winter. Some of our local skippers do the same, curling up in a grass stem or leaf. They use their spinneret to create a silken thread to sew their leaf closed as if zipping up a sleeping bag for the winter.
Last year my dad and I raised buck moths. The adult moths fly during the day, contrary to most moths, and very late in the season (November). The buck moth spends the winter as an egg mass attached to a branch or tree trunk. How the eggs do not turn crispy from freeze drying is beyond me.
Still another way that butterflies and moths survive the winter is as adults, hunkered down in piles of branches or rocks. There is no better example for this than was found when I burned our burn pile (an old piano, some old boxes, and some large branches) the other day. Not long after the fire started two moths flew out of it. Made me feel badly that I had disturbed their home, but I am confident they were able to find new ones.
As you look out upon the winter landscape, consider who is alive and well under the snow or on the branches in that woodlot. And look forward to the warmth of spring when those hardy souls will again bless us with their vibrant colors and spirited flitting about!