The Buzz on Mosquitoes

June 19, 2006 - The Houston Chronicle

By Kathy Huber
Copyright 2006 Houston Chronicle

What's good about mosquitoes? They whine in our ears, ruin a night on the deck, chase us from the garden ... oh, got it. They're frog food. Fish, dragonflies, birds and bats like them, too.

Mosquitoes are not only irritating but they also carry malaria, West Nile virus and St. Louis encephalitis, among other diseases. And they trigger heartworms in dogs.

Most mosquitoes do their nasty work in the dark. Females do all the biting; some stick close to home while others will fly up to 6 miles to get a blood meal necessary for egg development, says Mike Baum of San Jacinto Environmental Supplies.

Think you make a better meal than others? Could be. Scientists have been working for years to nail mosquito attractions. They know carbon dioxide in exhaled breath is a big draw. But it could be other odors on our skin.

Control

Mosquitoes need water to breed. Most prefer stagnant water. The larvae, or wigglers, molt and become pupae, or tumblers, which become adults. First order of business for the grownups is finding a mate.

We can help discourage emerging populations by emptying standing water around our homes and gardens. Dump those saucers beneath pots and kids' pools; tilt the tire swing. Clean your gutters. Add a fan on the porch or deck — mosquitoes prefer still air. Add mosquito fish to your pond.

These simple steps are effective, since this metamorphosis can occur in only nine days.

Mosquito dunks with BTi do an excellent job in preventing larva development in permanent water features and bodies of nondraining water. These dunks contain a bacterial strain that does not harm birds, fish and people.

To control adult mosquitoes, plan an orange oil attack during their daylight rest, Baum recommends. Garlic oil with soybean oil as a sticking agent also can be effective an repellent for several weeks, he says. Spray the solution on all exposed surfaces in the desired area — lawn, fence and ornamental beds.

"The garlic interferes with the mosquitos' sensing systems, so they go elsewhere to look for a meal," he notes.

Treating a 5,000-square-foot area costs $8.70 — about $2.18 per week, he says. Orange oil for the same area is $7.80. Mosquito dunks are about $1 each for a 100-square-foot area.

Fogging/misting systems introduced in recent years use pyrethrums derived from a type of mum. Natural pyrethrums have low toxity for mammals and break down quickly, but they are nonselective, meaning they can kill/harm other insects (butterflies, fireflies) upon contact. Some companies mix another agent with the pyrethrum for longer lasting control.

"Personal repellents containing DEET or Picaridin, although not organic, have been proved to be effective with minimal to no adverse effects when used properly," Baum says..