Have a mosquito problem? Look for them close to home, says expert

You’re settling down in your patio chair, ready to enjoy a book, a pitcher of lemonade, and the sun-warmed breeze, when a mosquito settles down on your arm. And another lands on your leg, while another buzzes right by your ear.

Virginia Tech entomologist Eric Day says that when it comes to controlling mosquitoes, there aren’t easy short cuts. “You’re going to have to be doing your due diligence, check in your outdoor containers, put the ladder up the side of the house to check the gutters. Find the water where these mosquitoes are breeding, tip over that water, dump the larvae on the ground, and that should help alleviate the problem.”

Q: What’s the most important thing a homeowner should know about mosquitoes?

“The big thing to know about mosquitoes is that they're container breeders. They need some kind of container to hold water. It could be an old tire, the gutter, a sheet of plastic. Any kind of thing that will keep and hold rainwater, that makes for a small container, is the perfect place for mosquitoes. That’s where they breed. The larval mosquitoes, the immature stages, breed in water, and then the adults emerge and fly around and look for a tasty blood meal and unfortunately, they find us.”

Q: What about streams or ponds?

“What a lot of people do is they want to blame a nearby pond or stream, but both ponds and streams have way too many other kinds of things, like fish and predatory insects, that are feeding on mosquitoes. Often, there's some kind of container, gutter, etc. very close by the house where they’re breeding, so when you find them, you kind of need to look local, look right near the house.”

Q: What are ways to repel mosquitoes?

“One thing you can do to protect yourself is to wear long sleeves or long pants to give mosquitoes less surface area to feed on. You can use DEET or products that contain DEET, that will help, too. Repellents work because they block some of the senses that mosquitoes are using to find you. If they’re getting in the house and you haven't seen him in the house before, check the screens on your windows. It may be that you have a broken screen or a missing screen.”

Q: Do bug zappers do anything to deter mosquitoes?

“As an entomologist, when I look in a bug zapper tray, there’s very few mosquitoes in there. It's kind of a lot of general insects that you’d find out in the yard. Actually, some beneficial predatory insects end up in there, too. It might give some folks satisfaction when they hear the zapping going on, but I don't think they’re getting real mosquito control.”

Q: Could climate change have any effect on mosquito populations?

“With the warmer winters, warmer summers that we're having, with seasons are starting earlier, there's more time for the mosquitoes to complete more life cycles — often mosquitoes have multiple generations through the year. You have to couple this with an adequate amount of rainfall that's going to fill those containers. If the effect is that you’re having dry weather and lack of rainfall, that would kind of tend to cause a decline in mosquito numbers. But in an area that is having more rainfall due to climate change, I would expect that, yes, you would see more mosquitoes.”

Q: Any other tips to share?

“Just to let everybody know, entomologists’ houses have mosquitoes, too. One source we had for a while was a water garden. Then we put goldfish in, so now we have goldfish eating the mosquitoes — and they do a good job — and we have the entertainment of watching these goldfish grow.”

Read more about these pesky blood-sucking insects in this fact sheet from the Virginia Cooperative Extension.

About Day
Eric Day is the manager of the Insect ID Lab in the Department of Entomology at Virginia Tech. His areas of expertise include insect identification and pest surveys.

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