Outdoors in the Green Hills Area: Insects And Winter

by Jeff Berti
Grundy County Conservation Agent
On the coldest days of winter, you can’t help but miss the butterflies and bumblebees. Just where do these insects spend the winter?
Except for a few that migrate; all of the insects you remember from the warm months are still around in the winter, even in your neighborhood. Some insects, such as honeybees, overwinter as adults. With others, only the pregnant females survive, spending the winter by hibernating under leaves, in tree bark or beneath shingles. Insects also overwinter as eggs or as immature young. In fact, it’s easy to see their feeding places and shelters in the winter season if you look at fallen twigs, trees, galls and egg sacs under the bark of trees.
If you see a willow or poplar tree, look for a tiny bit of curled-up leaf attached to a twig. Inside may be a future viceroy butterfly. A row of small holes on a twig houses cricket eggs. Another twig may hold cicada eggs. Some insect adults can be found buried underground in mud or leaf litter. But on a warm winter day, look around trees and on top of the snow for one of the few active winter insects, the snow flea.
Also on winter walks, you don’t expect to hear a chorus of frogs, or see snakes and turtles. Where have these animals gone?
Warm blooded animals have internal controls that maintain constant body temperatures despite outside conditions. Amphibians and reptiles lack such controls. To avoid extreme temperatures—summers that would bake them and winters that would freeze them—they must find sufficient shelter. Tolerable temperatures and adequate moisture are available underground, in springs and caves, and in the mud in ponds and stream bottoms. Toads, frogs, salamanders, turtles, snakes and lizards migrate to these spots at the onset of cold weather. As the weather grows colder and drier, they move deeper into their shelters.
Species vary in their preferred shelter and their periods of winter dormancy. Generally, amphibians tolerate lower temperatures better than reptiles, and so remain underground for shorter periods. Within a species, adults take shelter sooner than juveniles and stay in the shelter longer.
Because amphibians and reptiles are inactive in winter, they need little food, water and oxygen. Frogs and turtles buried in pond mud can breathe through their skin. Occasionally, turtles or frogs can be seen under the ice on ponds or streams.
So the next time you are outdoors enjoying the winter air, keep your eyes open for the subtle reminders that the insects, amphibians and reptiles leave while they are waiting for the warm days of spring to arrive.