Bzzzzz! The lake flies are back -- and to many, they're obnoxious!

SHERWOOD, Wis. (WITI) -- It's a sure sign of spring. Thick clouds of buzzing buggers known as lake flies are bothering fishermen and homeowners near Lake Winnebago -- and also folks near Lake Michigan. The DNR is reminding people that the insects aren't all bad.

The telltale hum is in the air.

Lake flies are causing headaches in High Cliff State Park.

"It's extremely bad.  It's very obnoxious," John Engelhardt said.

"They seem to be pretty nasty today.  They weren't that bad a few days ago, but today really brought them out," Brian VanCamp said.

Park naturalist Cynthia Mueller says the lake flies are particularly bad this year.

She says the recent storms -- and then heat and sunlight created perfect conditions for the hatch.

"We're seeing probably the biggest hatch we've seen in a decade or more," Mueller said.

Mueller says the flies are about two weeks late, because the ice took longer to melt than usual.

But the bugs are making up for lost time.

"I cut my lawn today and it was plugging my lawnmower up.  They were just really thick on the grass.  So I had to stop a couple times and clean the mower out," Engelhardt said.

"Right on the lake is pretty bad.  You need a power washer to get them off," VanCamp said.

While the lake flies are are annoying, they don't pose any dangers to humans and they even provide some benefits to other animals.

"When people see them they think they're a giant, big mosquito on steroids, but they're not.  They don't have any biting mouth parts or stingers," Mueller said.

"Sturgeon and other fish are actually consuming the lake flies in the larvae and pupae stages, when they're in the water," Ryan Koenigs said.

Birds are feasting on the adult flies.

And humans are making do, hoping for a short season.

"I grew up in High Cliff, so I know what they're like.  I just deal with them," Engelhardt said.

The lake flies live as adults only a couple of weeks. They reproduce, lay their eggs in the water, die and the cycle starts over again.