Gadgets and sprays kill or repel mosquitoes, but the most effective way to keep skeeters away is to eliminate their habitat, says Steve Divine, director of environmental services for the Northern Kentucky Health Department.

Public health officials urge property owners to get rid of standing water and containers, tires and other objects that hold water so mosquitoes don't have a place to breed.

"Any shallow pools of water that are there for longer than three days are potential breeding grounds for mosquitoes," Divine says.

Decorative ponds, wading pools and retention ponds are obvious sources. But the little puddle where the downspout drains is also a breeding spot. So is anything that holds water, including gutters, swimming pool covers, flower pots and planters and old tires.

The larvae of one recent arrival in the region - the Asian Tiger mosquito - can grow in as little as a tablespoon of water, says David Fankhauser, a professor of biology and chemistry at University of Cincinnati Clermont College.

"It lays its eggs on the insides of dry containers, and those eggs are dormant until it rains. When it rains, the water comes up and touches the eggs, and that triggers the eggs to hatch," Fankhauser says.

Divine says mosquito dunks, available in hardware and garden supply stores and nurseries, are effective at killing mosquito larvae in ponds, culverts and pools.

Ornamental ponds can be stocked with fish that eat mosquitoes. Adding a fountain also works: Mosquitoes like stagnant - not rippling - water.

Peggy O'Farrell