Each year, as the weather changes and temperatures get colder in Western North Carolina, the bug population seems to dwindle and disappear. So where do they all go? Are they leaving or hibernating? They seem to come right back once the winter thaws, so what’s the deal?
Insects have a variety of methods for surviving the coldness of winter.
In some instances bugs do migrate to warmer climates. While most people don’t consider this species as a pest, a primary example of this is the Month butterfly. Monarchs in the eastern United States and Canada fly up to 2,000 miles to spend their winter vacationing in Mexico. Many other butterflies and moths also migrate seasonally, including the gulf fritillary, the painted lady, the black cutworm, and fall armyworm. Common green darners, dragonflies that inhabit ponds and lakes as far north as Canada, migrate as well. Many crop bugs also migrate.
Just like many animals, many insect species hibernate as adults. Often, the bugs congregate at higher elevation levels to try to stay warm. For example, large wasps often seek shelter in the eaves and attics of homes and barns.
Tree holes, leaf litter, and under logs and rocks are also common shelters for overwintering adult insects.
In general, insects are able to survive cold temperatures easiest when the temperatures are stable, not fluctuating through alternate thaws and freezes. Many insects can gain shelter and nourishment through the winter in a variety of micro-habitats.
Among these niches are under the soil, inside the wood of logs and trees, and even in plant galls.
Blankets of snow benefit insects by insulating the ground and keeping the temperature surprisingly constant. Honeybees have been studied during the winter and are found to remain semi-active in hollow trees through the generation of body heat.
Insects that are inactive during the winter months undergo a state in which their growth, development, and activities are suspended temporarily, with a metabolic rate that is high enough to keep them alive. This dormant condition is termed diapause. In comparison, vertebrates undergo hibernation, during which they have minor activity and add tissues to their bodies.
Because of hibernation, it is important to continue treating your home throughout the winter months so prevent future infestations when the weather warms up. Next week, we'll write more on blog hibernation patterns during the winter! For more information contact Gibson Pest Control at 888-483-6507 or 828-684-1353.