Adam Fry is a bug guy. A 20-year veteran of the Metropolitan Mosquito Control Division, he’s used to facing creatures that make other Minnesotans run indoors. But the buggy situation in his own yard this summer was enough to give Fry pause.
A mosquito trap Fry set up in the trees outside his Jordan home was filled to the brim with gnats — over 100,000 of them.
Fry’s trap confirms what residents of Scott and Carver counties have suspected for weeks now: The gnats are truly bad this year.
“I’ve worked with the district for over 20 years, and I haven’t seen them this bad ever,” Fry said. “Usually for flies and gnats, they go away after the Fourth of July, when the mosquitoes kind of take over. But gnat populations are definitely elevated at this time of year right now.”
Mike McLean, public affairs coordinator for the control division, called the problem “off the scale.”
Gnat populations have boomed this summer because of an unusually wet fall, winter and spring, McLean and other officials have said. The bugs thrive in environments with nutrient-rich running water, a description the Minnesota River has matched to a T this spring.
McLean called it a perfect storm.
Since 1990, the division has been the metropolitan area’s first line of defense against mosquitoes, gnats (also known as black flies) and ticks. It uses pesticides against Minnesota’s summer bugs to try to leave enough to keep the natural balance of the ecosystem while killing enough for residents outside.
“Ordinarily, our black fly treatments are very effective,” McLean said. “If you take a look at the number of black flies that you see in the metro area compared to places where we don’t treat, historically we get about an 11-to-1 reduction.”
While those numbers are something to be proud of, they’ve created high expectations, McLean said. This year’s flooding along the Minnesota River delayed the division’s early spring treatments, allowing a generation of gnats to grow and emerge from the river unencumbered.
“People have gotten used to not seeing a lot of gnats. So when you get a year like this, this is kind of like a window into how it could be if we didn’t do our treatments.”
The gnat problem has attracted, like a moth to a flame, the attention of social media and news crews, including the Wall Street Journal, which sent a reporter and photographer to Belle Plaine, Jordan and Shakopee to document the gnarly problem last week.
Earlier this month, a resident’s post about gnats on the Concerned Citizens of Shakopee Facebook page attracted over 100 comments.
“Gnats can travel considerable distances up to about 30 miles, and winds can affect where they move to,” Fry said. “I think they are way worse if you live within 10 miles of the Minnesota River and Scott and Carver counties.”
Carey LeMere, a division black fly specialist, said the species Simulium meridionale, known as the turkey gnat, is the main one driving area residents nuts. The turkey gnat and 10 other species of gnats call the Minnesota River home.
Gnats don’t carry diseases in North America. In extreme cases, numerous gnat bites can cause fevers in children and elderly people. Birds such as loons, pets and livestock are most at risk for disease and stress when gnat populations get bad.
On May 12, Minnesota River levels dropped enough for division crews to do their first treatment. A crew treated three sites in Shakopee, Jordan and Belle Plaine and planned to treat four more this week.
The treatment consisted of pouring 264 gallons of Bti — a soil bacteria that attacks gnat larvaes’ guts and eventually kills them — into the river. According to John Walz, the control division’s black fly control coordinator and president of the North American Black Fly Association, each treatment reached about 2 miles of river, creating almost total coverage between sites.
“We’re going to get a good start today,” Walz said during the treatment. “We’ll see, hopefully, pretty fast — within two weeks— really a reduced number of gnats.”
Until then, Walz advises residents to forget fashion and wear light-colored, long-sleeved clothing, maybe even a head net if the situation is truly miserable.
“I mean don’t laugh about a head net. And I’m sorry to say that because I feel bad that we haven’t gotten out here to help,” Walz said. “Repellents also help. Deep Woods OFF and that kind of thing works pretty good.”
There is perhaps one silver lining in all of this. More gnats are a natural indicator of a river system in balance.
“It is an indicator of water quality,” McLean said. “You know it doesn’t mean clear water. But a more balanced ecosystem is going to produce huge amounts of black flies. They have a job to do like anything else.”
Fifty years ago, ecosystems like the Minnesota, Mississippi, Rum and Crow rivers were just drainage ditches, McLean said, not healthy ecosystems. But the emphasis on water quality over the last 30 to 40 years has made a difference, he said,
“One of the differences it’s made is that it’s suddenly a wonderful habitat for black flies.”