Light pollution could be why mosquitoes are active for longer periods during the year than they used to be, according to a study by the Ohio State University. The research appears to show more evidence that development and brighter lights might result in a longer bloodsucking season for the insect.
“They’re maintaining really high levels of activity throughout the night, when ordinarily, they would kind of be pulling back, they’d be slowing down, not as behaviorally active,” said one of the researchers, Matthew Wolkoff, a doctoral candidate at OSU.
Wolkoff said the study involved raising Northern house mosquitoes in summerlike conditions with more light and winterlike conditions, during which the duration of light in a day is reduced. What the results showed is that increased exposure to light prevents the bugs from moving into a dormancy period known as diapause.
Northern house mosquitoes are common in North America and are known to carry West Nile virus, which can be fatal, according to the Centers for Disease Control and Prevention.
Wolkoff said while this small-scale study does not provide definitive proof, it appears to show that the light could prevent female mosquitoes from taking cues from the sun and the amount of daylight during a day to figure out when to slow down on the hunt for blood and turn to feeding on nectar and sugar sources. Female mosquitoes feed on blood when producing eggs.
“They’re not accumulating certain reserves of like body fat, and a couple of other metabolic nutrients, like glycogen and stuff that they should be accumulating in preparation for winter,” Wolkoff said.
Other studies have also shown the impact light pollution might have on not just mosquitoes but other insects as well, according to Wolkoff. He suspects an increased use of brighter lights as opposed to softer lights outdoors could also play a role. Wolkoff said studies on that topic are underway.
As a scientist, Wolkoff said further studies are needed before there is a call to action, which could include encouraging communities to lengthen the time mosquito control activities take place in urban areas.
“I think it’s something that the public should keep in mind that a lot of the effects of humans on the climate or on the world around them can be very broad and kind of come from unexpected places,” Wolkoff said.
He also said it could eventually help us learn how to protect other beneficial insects, which may be affected in the same way.
“We don’t want beneficial insects, or benign insect species, to also experience these negative effects of artificial light at night,” he said.
The study was presented in the journal Insects.
