Warm winter’s impact on Delaware mosquito population

The state has already started spraying woodland pools to kill mosquitoes at the larval stage about a week earlier than usual.

So does the warm winter and early start to spraying mean Delawareans will be swatting the pesky insects more than ever this year?  Not necessarily, says the state’s Mosquito Control Administrator Dr. William Meredith.  “The only thing we can say is it’s going to be dependent on temperatures and rainfall patterns.  And we’re not good enough, and neither is the weather man, to tell what’s going to happen from now until late October.”   So if the summer continues this year’s warmer-than-usual trend, and Delaware gets a lot of rain, that could mean a much larger mosquito population.  “The worst would be a very warm and a very wet summer.” 

He says the early development of mosquito larvae has been sped up thanks to the early arrival of spring.  “We’re concerned about how fast the immature aquatic stages of the larvae are developing due to these warm temperatures.”  The spraying process had to start early to attack the bugs at that early stage.  “There’s only a certain stage in that immature life-cycle when you want to apply the insecticides.”  There’s also an urgency to spray early because the early warm weather will cause trees to grow their leaf cover sooner, which blocks the application of insecticide.

Insecticide supply

While the state didn’t have to worry about breaking DelDOT’s salt budget to combat icy roads, the Department of Natural Resources and Environmental Control may break the insecticide budget this year.  Meredith says if DNREC doesn’t use contingency funds to replenish their supplies, they’ll run out of money to buy and apply insecticides.

Supplies are dwindling thanks in part to the affects of Hurricane Irene last August and into September.  “We were literally getting- over about a three to four week period- several thousand phone calls for relief,” Meredith says of the state’s response to all the standing water dumped on Delaware by the tropical system.  “We were pretty aggressive, we did what we had to do, and it depleted our spray budget a fair amount.”  He says the state is trying to get some of that money back from FEMA because it was a state of emergency.

Complaints about mosquitoes

Meredith encourages residents to call his office if the mosquito population in their area start to get out of control.  “Any time the discomfort level is more than they can tolerate,” he says.  “We’re one state agency that likes to get yelled at, because when we hear from the public, that help us focus our limited control resources for where to work.”  

If you need get relief from unbearable mosquitoes, you can call the Glasgow field office, which covers New Castle County and the northern half of Kent County including Dover at 302-836-2555.  If you live in the southern half of Kent County or Sussex County, you can call the Milford field office at 302-422-1512.