Better buy more bug spray: The mosquitoes have taken over.

This summer could be one of the 10 worst for mosquito production, and it's not over yet. The wet August, on top of an already wet summer, has hatched a new crop of bloodsuckers.

"Each of these big rainfalls is going to produce a crop of mosquitoes," said Stephen Manweiler, executive director at the Metropolitan Mosquito Control District, which tracks the number of mosquitoes across the metro area.

"There are hundreds of billions of mosquitoes out there. They'll be around for awhile."

The Twin Cities had nearly 8 inches of rain in August, nearly twice as much as a year ago, making it the sixth-wettest August on record, according to the National Weather Service.

And with more rain in the forecast, residents may not see a reprieve any time soon. Wet soil, often pooled with water, is the ideal surface for mosquitoes to lay eggs — lots and lots of them.

More than 50 mosquito species occupy the state, but the one that people are most likely to swat is called the Aedes vexans. It's overwhelmingly to blame for all that slapping. "They're very aggressive biters," Manweiler said.

The pest can spawn several generations throughout the summer.

In general, the northern parts of Anoka, Hennepin, Washington and Ramsey counties tend to have more mosquitoes than the rest of the metro area, according to the mosquito district, which maintains data-collecting sites.

The control district typically crunches numbers in September to see how much and how often to treat infested areas.

"We can't really catch a break when it comes to the frequency of the rain events," said Mike McLean, the district's communications director. "The data may not show that this is the worst year yet, but the lateness of the arrival of mosquitoes and the intensity have added up to people saying, 'Wow, this is horrible.' "

They may linger in numbers until the first decent frost. "That'll shut everything down," Manweiler said.

Athena Priest, owner of the Tin Fish restaurant on Lake Calhoun, said mosquitoes haven't affected business. On the other hand, customers certainly aren't lingering at the outdoor tables.

"I wouldn't say that it scares people away, but people finish eating quickly and get themselves out of here," she said.

At Sea Salt Eatery on Minnehaha Falls, where wide doors open onto the patios, workers say they've experienced one of the worst mosquito seasons in years.

"It doesn't matter what type of day, it seems like," said manager Martine Lizama. "Inside, standing at the register all day, you get bitten up."

Liz Sawyer • 612-673-4648