After heavy rains, beware of rise of giant mosquitoes

Thursday, May 4, 2017

A wave of dangerous storms that recently rolled through the state brought large amounts rain and snow and now may also have sparked a rise in the population of giant pests known as floodwater mosquitoes.

Common in Oklahoma, floodwater mosquitoes, sometimes called gallinippers, can grow up to six times larger than common mosquitoes.

While the disease potential is low with this particular species of mosquito, the nuisance factor is high, said Justin Talley, Oklahoma State University Cooperative Extension livestock entomologist.

“Floodwater mosquitoes are associated with very painful bites. They are huge so people may begin to notice them if the weather warms up,” Talley said. “We’re not really concerned about the disease potential so much as having a lot of breeding material available to them, which in this case is water.”

Oklahoma often sees large populations of floodwater mosquitoes in May and June, especially after heavy rains.

Getting rid of as much standing water as possible around the property will help prevent mosquitoes from building up.

That means checking places that have the potential to hold water, such as bird baths, containers in gardens and even tree holes and making sure the water is draining.

If standing water is not draining from the property, then products are available that can be applied to the water. Known as insect growth regulators, they usually can be applied as a granular from a standard lawn fertilizer spreader.

“The main concern with standing water is the potential to serve as a breeding ground for mosquitoes,” Talley said. “For floodwater mosquitoes, it’s usually wooded habitats or roadside ditches where the water is not moving or slow-moving. If the water is moving, there’s really no mosquito development going on.”

Following some general precautions can reduce the chances of getting an unpleasant bite from a floodwater mosquito.

The pests are typically more active around sunset and in shady areas. They will bite humans, livestock and pets.

Especially while enjoying outdoor activities, wear long sleeves and long pants. Although floodwater mosquitoes are large enough to bite through clothing, some coverage can provide a first line of defense.

The most effective protection, however, comes from repellants containing at least 25 percent DEET.

Some natural products, such as lemon eucalyptus oil, also may work as repellants but have varying results.

Repellants with DEET should not be applied on children 3 years or younger and no repellent of any kind should be used on children 2 months or younger.