What elements cause elevated mosquito populations in Denver?

Heat, rainfall, and standing water can help mosquitoes breed faster than usual. That’s why mosquitoes tend to be worse in years with a lot of summer thunderstorms.

If this summer feels worse than last year when it comes to mosquitoes, it’s not your imagination. And it might not even be just you, either. If your yard suddenly has more mosquitoes than you remember, it probably ties back to how much rain Denver has gotten recently.

Mosquitoes need standing water in order to breed. Females lay their eggs in or near water, and the larvae develop entirely in water before they emerge as adults. It’s a quick lifecycle, too, as an egg can become a biting adult in as little as 10 days when temperatures are warm. That means every puddle, clogged gutter, birdbath, and overturned flower pot saucer that holds water for more than a week could become a mosquito nursery.

Denver's afternoon thunderstorms are often behind big mosquito surges. A heavy rainstorm will create, in the span of a few minutes, thousands of temporary water pools across neighborhoods, parks, and open spaces. Unlike a permanent pond that supports predators like fish and dragonfly larvae, these temporary pools have no predators. That means floodwater mosquito species Aedes vexans are freely able to hatch in massive numbers after storms, and Culex species breed in the irrigation ditches and drainage infrastructure that stays wet all summer.

Temperature is also a big factor. Mosquitoes tend to be at their most active between 50 and 95 degrees Fahrenheit, and they need at least moderate humidity. Denver’s semi-arid climate limits mosquitoes more than humid environments, but the summer heat and storm-driven moisture still give mosquitoes plenty of microclimates to call home.

You can’t control the weather, but there are some things you can do to alleviate the issue in your own yard. If you have a lot of dense vegetation, shade, and organic debris, that can give adult mosquitoes places to hide during the heat of the day. Properties with thick landscaping, woodpiles, or unmaintained areas adjacent to irrigated lawns tend to harbor higher populations.

If you’re a West Denver homeowner and you’re dealing with more mosquitoes than usual, Mosquito Squad of West Denver can help. With a professional barrier treatment, you can target the places where mosquitoes breed and hide. When you work with Mosquito Squad, a trained technician will check out your property to identify the conditions causing your mosquito problem. Then they’ll apply treatments that continue working for up to 21 days between visits.