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New species of aggressive gnats bugging people in the Twin Cities

These black flies have emerged earlier and are different from the ones that the MMCD treats.
A black fly. 

A black fly. 

Are gnats bugging you? You're not alone. People around the Twin Cities metro have reported multiple welts on their necks this spring from these biting bugs.

This comes as the Metropolitan Mosquito Control District (MMCD) has reported a new species of gnats (also called black flies) in some areas of the Twin Cities. 

And this species is being called more aggressive than the gnats we're used to, Fox 9 reports.

"The new species of gnat (Simulium tuberosum) has been found in a few places around the Twin Cities," Alex Carlson of MMCD told Bring Me The News. "We are getting lots of calls about gnats (we call them black flies) and we are investigating whether these calls are about the new species or the species we know and already monitor and treat." 

The gnats were bad last spring, too. The MMCD said it was difficult to treat areas due to high water levels. But this year, the issue seems to be black flies emerging earlier and a different species that they don't normally treat, Carlson said. 

"We are in heavy data collection mode right now to learn more about what we're dealing with – what species, exactly, and where they come from," he said.

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This surge in this species of black flies could be because other gnats the MMCD has treated for has given these bugs an opportunity to expand their range, the MMCD's John Walz told MPR News

The MMCD has started conducting surveillance and treatment for mosquitos and black flies in the areas it covers, including along the Minnesota River. 

"So there will hopefully be some relief for people affected by those (black flies that we typically see)," Carlson said.

This new species of black flies, though, the MMCD may not be able to treat for until next year. But there's some good news: "From what we know it sounds like a one-generation species that will hopefully last only 2-3 weeks," Carlson said.

To protect yourselves from the biting flies, MMCD recommends people wear EPA-approved bug spray (DEET, picaridin, or oil of lemon eucalyptus are most effective), cover your head and neck, wear light colors, and avoid peak times. And the good news is gnats, mosquitos and ticks can't spread COVID-19, the MMCD says.

These black flies are different from the swarms of bugs that were reported near Lake Minnetonka and Prior Lake in late April. These weren't mosquitoes, they were chironomid midges, with Metropolitan Mosquito Control District noting they aren't harmful, but their swarms can be annoying.

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