By Katie Nichols
If the recent cold snap had hopes of an insect-free season springing to mind, think again.
Even after a week of frigid temperatures—uncharacteristic even for Alabama winters—insects will likely survive.
Dr. Xing Ping Hu, an Alabama Extension entomologist said insects are not usually susceptible to cold temperatures.
“Some crops, fruit trees and even livestock animals may fall prey to cold weather, but insects can survive even record cold,” Hu said.
Insects Are Always Adapting
“Insects have been around for ages and have survived a wide range of weather conditions,” Hu said. “They have developed strategies for surviving even in the coldest temperatures by entering diapause—ceasing to feed, grow or reproduce—by hibernating in protected sites, by burrowing deep down into protective sites—such as leaf litter or the ground—or by sneaking in to human-built structures.”
Hu said some insects also find shelter in hollow logs. Over time, some species will develop a higher tolerance, and in some cases—a resistance–to colder weather.
Cold Weather No Match for Many Insects
Alaska and Minnesota are prime examples of the adaptive nature of the insect. These states, known for brutal winters, also have ruthless mosquito populations in the summer.
“Both states are also known for active mosquito populations during the summer,” Hu said. “In fact, mosquitoes are far more susceptible to the lack of spring rainfall than they are to prolonged and unusually cold weather.”
Furthermore, the recent cold snap was not cold or long enough to make a noticeable difference in insect populations.
“Fire ants need two weeks of temperatures below 10 degrees Fahrenheit to have any effect on the number of ant colonies,” she said.
Common Household Insects
Aside from mosquitoes and fire ants, other urban insects Alabamians are familiar with—termites, cockroaches, wasps, bedbugs, flies, fleas, and various ant species—are also resilient.
“Most insects have a breaking point, but cold weather typically is not one of them,” Hu said.
Termites avoid freezes by burrowing deep into the ground, underneath fallen logs and rocks. Their activity slows during winter but rarely completely ceases.
Cockroaches living inside homes or other structures have no problem at all with the winter. Roaches living outside survive freezing temperatures by hiding in safe and warm places such as organic litters, inside fallen-logs, or composters with basic necessities: food, warmth and a hiding place.
While most wasps die off in the fall, a few will move into sheltered spots to ride out the winter.
“They usually go dormant until the spring,” Hu said. “Bees stay inside their hive and keep themselves warm by fluttering their wings. The queen always remains at the center to increase her chances of survival.”
Bedbugs never leave the house. Inside homes with temperatures above 65 degrees, they are active through the winter. Bedbugs are dormant in temperatures below 65 degrees.
Houseflies rarely survive freezing temperatures outside, but they live well with adequate protection and food sources. Cluster flies also overwinter in protected locations, such as a wall void in the home, and emerge on warm days.
Most fleas survive cold temperatures by sticking with warm-bodied host animals.
Ants live in groups called colonies. They fend off freezing cold by clustering together, sealing the entrances to their nests and entering a dormant stage.