We know that during the winter months, bears hibernate, but did you know insects overwinter. Larvae for example burrow into their shelters, like leaves or mulch to keep warm during winter months. Nymphs may live under the ice surface of a pond during the winter. Pupae on the other hand will come out in the spring as a adult.
For insects, the purpose of overwintering is to find some warmth, in order to make it through the winter. The insect goes into what is called diapause, which halts its growth. During this time the insect goes through either physiological or biochemical changes, in for it to survive. The insect can tell when the days begin to grow longer, as in when its spring time.
There are even insects that migrate, like the Monarch butterfly. This insect can only survive in warm temps.
You also have insects that make their winter homes in our homes. They may choose our homes eaves, our siding, or cracks or crevices they can find.
The cluster fly, which some think is a house fly can cause much consternation for residents. These flies survive the winter months and can be a pest.
To control indoor emergence of overwintering pest, prevention can be done. Go over your home any seal any cracks or crevices. Caulk your doors and windows and any pipes. Any siding that has cracks needs to be caulked. The same with your foundation. Check your eaves and roofs, and also repair any torn screens.
Doing this will help in the spring, when insects are ready to come out in full bloom.