A helicopter from the Metro Mosquito Control District dropped anti-mosquito pellets over a wetland area near I-494 and Dodd Road in Egan. (Stan Schmidt — Star Tribune/The Minnesota Star Tribune)

Ice was still on the larger metro lakes Tuesday, but there was no better time to get after the mosquitoes. In its first such foray of the year, the Metropolitan Mosquito Control District deployed three helicopters across the region, aiming for 1,500 acres where three varieties of mosquitoes might be developing in snowmelt from eggs laid last summer.

"They're available to hatch as soon as the snow starts to melt," MMCD spokesman Mike McLean said. "A lot of them are found from here all the way into the tundra. They're well-adapted to winter."

Tuesday's spring offensive was about a week later than normal, due to lingering cold and snow, but a week earlier than last year's.

McLean added that despite the 16th-snowiest Twin Cities winter on record (so far), standing water after the melt and even some stream flows are about average or even below. State climatologist Greg Spoden said that's likely because much of the winter's snow fell during very cold weather and thus had a relatively low water content.

"Of course that could all change if we get a good soaking rain in the next couple of days," McLean said.

The helicopters dropped pellets of methoprene, which prevents mosquito larvae from becoming flying, biting, breeding adults while leaving them available as a food source to other aquatic creatures, McLean said.

The targeted species — which carry the incriminating names Aedes excrucians, Aedes abserratus and Aedes stimulans — can grow into large, aggressive adults that can live one long generation, into late June or early July, McLean said. That's when they're usually succeeded by the daintier but more numerous and annoying Aedes vexans, a warmer-season floodwater-breeder.

MMCD workers actually attack mosquitoes through the winter, placing anti-mosquito materials by hand on top of ice in cattail areas. That stymies a species that lays its eggs on the water and develops while attached to the roots of cattails through the winter.

MMCD spends about $1.8 million of its $17 million annual budget on helicopter operations that cover 200,000 acres in the seven-county metro area. It works to control 16 of the 51 mosquito species that have been identified in Minnesota — the ones that bite, that is — as well as ticks and blackflies, some of which are known to carry diseases.

McLean said deer ticks, which carry Lyme disease, are already out and "on the move" in thick underbrush and wooded areas. People should check for the ticks, which are smaller than the better-known wood ticks, on their clothing, themselves and their dogs after any outing, he said.

The MMCD will examine bugs people send them in vials or attached to tape and determine their identity, free of charge, he said. The address is 2099 University Av. W., St. Paul, 55114; people can also call 651-645-9149 for mailing instructions.

More information is available at www.mmcd.org.

Bill McAuliffe • 612-673-7646

A helicopter dropped anti-mosquito pellets over a wetland near Interstate 494 and Dodd Road in Eagan. The pellets prevent larvae from becoming biting adults, while leaving them as a food source for other creatures. (The Minnesota Star Tribune)

Stock image of a mosquito (The Minnesota Star Tribune)