Voracious biting black flies hatched in rain-swollen creeks and rivers are on a feeding frenzy in some Twin Cities neighborhoods, sending some victims covered with itchy red welts out of their yards and others into doctors' offices in search of relief.
Meanwhile, recent rain combined with warm weather likely will be a boon to Minnesota ticks, which have been infecting more people with Lyme disease as they expand their territory throughout the state. About one in every three adult blacklegged ticks (also known as deer ticks) carry the bacteria that transmits Lyme disease, as do one in five nymphs, which are about the size of a pinhead, said Dave Neitzel, a vectorborne disease epidemiologist at the Minnesota Department of Health.
As the ticks peak in June, other bugs will follow: mosquitoes that buzz and bite, flies that circle and chomp and swarms of midges that you inhale on evening walks.
"It's the price we pay for nice weather," said Jeff Hahn, University of Minnesota extension entomologist.
In the Twin Cities, the Metropolitan Mosquito Control District is attempting to keep the mosquito and black fly populations at tolerable levels.
To keep biting gnats in check, the district adds a liquid bacterial product to kill the larvae in streams and rivers.
But because of high water in rivers and creeks this year, the district has treated just 80 percent of what it usually does to diminish the black fly population, said district spokesman Mike McLean.
"When streams overflow, it's useless to treat it because the [treatment] doesn't end up in the channel. It ends up in the backwaters, and then you're not really controlling anything," he said. "There are going to be some spots in the metro area where people are going to notice some intense black fly populations."