The Misconception of the Polar Vortex’s Impact on Mosquitoes

Author: Mosquito Squad of Greater Washington DC

When talking to our customers, it seems many of them think harsh winters mean fewer insects in the spring and summer.  We know the much talked about Polar Vortex that Maryland and other states endured this past winter must mean the mosquito population has to be less this year. Right? That’s not the case.

If you think about the number of millennia insects have faced warm and freezing winters, yet are still with us, you know they must have a way to adapt to severe climate changes.  Mosquitoes are extreme survivors.  Ask any Alaska resident if mosquito numbers are reduced in years with icy winters.  They will tell you the answer is ‘No.’  Our 49th state has 35 mosquito species, and they all survive the sub-zero winters very well each year.  Maryland has 59 mosquito species, and all have adapted equally as well to our winters too!

So how do they survive? 

Mosquitoes survive like most species by first timing their lifecycle to seasonal weather changes.  As eggs, mosquitoes can survive very harsh winters.  Harsh winters and the cold water eggs may slow down the development of the mosquito egg which means in long, cold winters, they will hatch later in the spring but they will still hatch.  This developmental slowdown is called diapause by scientists and is an adaptation used by many insects, not just mosquitoes.

Adult mosquitoes survive winter by hiding in any warm, moist place they can find.  Heavy, damp leaf litter, in tree bark, openings in trees or deadfalls are among their favorite hiding places.  If mosquitoes can find warmth in garages, attics, walls and other areas in your home, they will over-winter there also.  Even animal burrows underground will keep mosquitoes warm and moist during harsh winters.  Warmth and moisture are the necessary elements for larvae and adult stage mosquitoes to survive cold winters.

Adult mosquitoes have developed two adaptations to help them further survive cold winters.  The first is a process that turns their body’s fluid into glycerol as the weather cools.  Glycerol acts like an anti-freeze to keep them from freezing.  Like other insects, mosquitoes also use an adaptation called “supercooling.”  As cold weather approaches, they begin to lower their temperature so they can survive much more freezing temperatures.  A mosquito that can’t find a place warm enough to keep them above their lower supercooled temperature won’t survive winter, but most do.

Equally as important as warmth is to mosquitoes is moisture and dampness.  Mosquitoes in any lifecycle stage need moisture, or they will dry out.  Our wet spring, on top of plenty of water from snow-melt, has provided an ample amount of warm and damp hiding places for mosquitoes to get the moisture they need this year.  Increased rains this spring warmed our lakes, rivers, and streams.  This quickly restarted Marylands’s mosquito eggs developing toward adults. The increased rainfall we’ve had this spring gave these pests many more places for eggs to develop and hatch.

The cold truth is;  weather temperature influences the mosquito lifecycle, but it has little effect on their survival rate. Heat and rain mainly affect the time when mosquitoes hatch.  In areas like Rockville and all over Montgomery County, hatching and mosquitoes emerging from hibernation generally begin each year around mid-April or earlier.  For more information on The Four Seasons of Mosquitoes, you can visit the Department of Agriculture’s website.

The Only Good Mosquito Is a Dead One!

Since mosquitoes aren’t good fliers, most spend their lives within a few hundred yards of where they are born.  To reduce the number of mosquitoes on your property, it’s important to begin protecting your yard early with a barrier spray.  We want to serve all of our customers before mosquitoes are a problem and at a time that is most convenient for you.  The earlier you call, the more flexible we can be in scheduling the protection you want for your family and friends who will be enjoying your yard this summer.

Mosquito Squad of Greater Washington DC offers an intensive mosquito control program that controls and prevents mosquitoes all season. Our highly effective barrier sprays are sprayed on a regular schedule throughout the mosquito season to ensure no gaps in your mosquito and tick control. We also offer an organic mosquito control spray that is highly effective in controlling mosquitoes as well!

Our goal is to keep you, your family and your pets completely protect you from mosquitoes and the many diseases they carry for the entire season.