Rob Malcolm Reporting

YOLO COUNTY (CBS13) — An annoying gnat explosion in the valley was caused by the wet winter.

Like columns of smoke floating over the trees in the Yolo Causeway, there’s only one way to describe them: “You know like birds when they swarm its the same thing swarms of insects,” said Gary Domeny from Sacramento.

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At this time of year, the little bugs seem to be everywhere.

“There can be literally millions of these little flies in these swarms and sometimes you can hear them,” said Dr. Lynn Kimsey, Bohard Museum Entomologist.

Kimsey says its mating season for the adult midge. Up close they’re not so pretty, but they’re out looking for partners.

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“They form these swarms so they can find each other,” Kimsey said.

As students prepared for Picnic Day at UC Davis, even the pesky bugs could not ruin a picture-perfect day.

You can thank the long, wet winter for this great year of midges.

“It’s big this year because I think we had so much water that you had a huge amount of survivorship from the larvae to the adults,” Kimsey said.

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The bugs are a bit of a pain and when you’re driving you’ll notice your windshield gets dirty more quickly, but they’re harmless, so we can still enjoy the great outdoors.