Frank Hale, an entomologist at the University of Tennessee at Knoxville for 15 years, said, "Insects have a way of producing their own kind of antifreeze. They get in their antifreeze-type mode and stay dormant all winter."
If the weather turns really cold once they become active, "They just don't have the same level of protection."
"You'll see it with fire ants," Hale said. "It gets warm. They come to the surface. If the weather turns cold again, it kills them."
Some people might consider fewer wasps a good thing, but it could be bad news for crops.
"Wasps are predators," Hale said. "In your garden, you'll find them preying on caterpillars and other insects that want to feed on your plants and vegetables. In a tobacco field, they'll feed on bud worms and horned worms that are feeding on the tobacco. These wasps probably do more good than harm."