A mature male Common Whitetail displays namesake white waxy coating on his wingsand abdomen.Submitted photos

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Green darner dragonflies are easy to love, particularly since this summer they have been keeping the mosquito populations under strict control by feasting on them. Swarms of these insects have been noticed by many residents along Evanston’s lakefront and other favorite summer spots.

A dragonfly has excellent vision, with two huge compound eyes that give it nearly 360-degree vision.

Each compound eye contains as many as 30,000 lenses. Dragonflies have four wings, are expert fliers and can fly straight up and down and hover like a helicopter. They catch their insect prey by grabbing it with their feet. According to Smithsonian.com, a single adult dragonfly can eat as few as 30 or up to hundreds of mosquitoes per day.

Green darners are the most common of the dragonflies. Doug Taron, Ph.D., of the Peggy Notebaert Nature Museum says the growth of the dragonfly population is mostly caused by the increase in the mosquito population.

Because of rainy weather early in the summer, there have been more mosquitoes than usual. As a result, dragonflies have shown up a month earlier than usual.

June helped boost the mosquito population, creating more morsels for dragonflies. And because dragonflies also eat mosquito larvae, their numbers are growing.

Green darners are not really fussy about water quality. They can cope with a degree of pollution, so their species has remained more common in the modern environment than other dragonflies.

Like mosquitoes, green darner dragonflies start out their life in water. As larvae, dragonflies eat the larvae of mosquitoes. As adults, dragonflies feed on adult
mosquitoes.