Numbers Increase
Insects and their eggs tend to weather winter either aboveground or belowground: Belowground bugs aren't usually bothered by the cold, but aboveground insects don't deal well with the cold. When the temperature drops – especially below zero – these insects can die off. But a mild winter leaves more aboveground insects alive, which means more wake and hatch when the weather warms, leading to more insects in spring and summer.
Bugs Have More Food
Here's another important consideration – a mild winter often means a lot of moisture and early plant growth. That means that many insects will have early access to plenty of food, allowing them to survive and form new colonies more quickly. Warmer temperatures can encourage insects to push on into homes, attack vulnerable wood or soil, and infest the spring trees and plants that are starting to bud early.
Also keep in mind that mild winters make it easier for fungi and other destructive growths to form, so your trees and garden may be endangered by more than just some eager bugs.
Water-Loving Bugs Get an Early Start
All right, how does a mild winter for bugs affect those unpopular mosquitoes? Well, it's all about breeding: Mosquito eggs tend to last the winter unless temperatures plummet unexpectedly, but the real activity begins when they hatch in spring. A mild winter means that mosquitoes hatch earlier with more sources of moisture, so they can go through more generations beginning in spring and become an even worse problem in late summer.
This cycle is closely related to how much rain we receive in spring and how much you water your lawn as well. But in general, expect mosquitoes earlier and that their numbers will multiply more quickly than in years with colder winters unless professional mosquito control options help out.
Natural Enemies Also Get an Advantage
Not everything is bad news when a calm winter leads into a warm spring. This also means that many animals that eat bugs will have survived and will be more active. That includes birds, lizards, rodents and a variety of other species (including other insects) that will also grow easily to keep the insect populations in check. This is important to remember if you prefer more natural or green methods of pest control.
Ticks
A warmer winter won't necessarily result in more ticks, but it can mean an increase in tick activity sooner in the season, increasing the likelihood of tick bites. Tick-borne illnesses like Lyme disease are on the rise across the U.S., so limiting exposure to tick bites should be a priority as the weather warms. Use caution in areas with brush and tall grass, as well as the transition between grass and wooded areas in your yard, at the park, in the forest or on the trails. Consider adding flea and tick control to your pest services. And no matter where you are outdoors, limit exposed skin, use bug spray and check for ticks to be safe.