TBO.com - TBO is Tampa Bay Online

County Bites Back

Tribune photo by ROBERT BURKE

Ram Maistri, with Mosquito & Aquatic Weed Control, fills a helicopter pod with AquaBac 200G bio-degradable granulars to kill mosquito larvae in saltwater ponds at Wolf Creek preserve in South County.

ADVERTISEMENT

By SUSAN M. GREEN

The Tampa Tribune

Published: July 3, 2008

Updated: 07/03/2008 06:11 pm

RUSKIN - The rains sweep through like a pail of water splashing a sleeping giant, and Wolf Branch Creek preserve springs to life.
Wading birds stalk the ponds and inspect lingering puddles for signs of prey. Butterflies and dragonflies flit through the high grass. Ducks dive and shimmy in a mid-morning pond bath.

The ducks aren't the only ones wriggling in delight. Below the water surface is the next generation of mosquitoes, hundreds of them, squirming to push themselves to and fro for food and oxygen.

But not for long. Overhead, a lime green helicopter whirs into view and lands, its blades beating the air and parting the reedy meadow vegetation like Moses at the Red Sea.

The bug busters are here.

"This is the perfect habitat," says Donnie Hayes, general manager of Hillsborough County's Mosquito and Aquatic Weed Control section.

"This all holds water," he explains, waving his arms around a grassy area dotted with palm trees and pine saplings. "There are low areas all through here. ... When it rains, the land catches 2 to 3 inches of water that will be there a week."

That's enough time for mosquito eggs to become larvae and mature into the flying, biting pests that have plagued people since time began. Natural predators can't keep up with the sheer numbers. Mosquito Control can't either, but officials think a change in tactical maneuvers in recent years is giving humans the edge.

"Larvae are easier to target because we know where they're at," Hayes says. "It's got to be in water. Once they get on the wing, they can go anywhere they want to go."

Likely they will make a beeline for the tree line. On the other side are the homes of MiraBay and Braemar subdivisions and the promise of human prey at backyard barbecue grills, pools and playgrounds.

The officially recognized mosquito season in Tampa Bay runs from May to October, but typically the complaints start pouring in with the summer rains, officials say. Often the Fourth of July weekend kicks off the busiest period for Mosquito Control.

That's important because mosquitoes can carry debilitating or even deadly diseases.

It's Mosquito Control's job to knock down the tiny predators. In the last three years, the department has modified its tactical maneuvers to put more emphasis on dumping corn meal laced with bacteria lethal to mosquito larvae into likely breeding grounds.

Crews still conduct nighttime air raids and attacks by truck on the parent insects, spraying insecticide mists where needed, Hayes says.

But targeting larvae is better for the environment and less likely to result in collateral damage, such as honeybees or butterflies or fish farm casualties, Hayes says.

"When we spray at night with the mist," he says, "whatever insect is flying is going to get hit."

The prevalence of cell towers in recent years makes night flight more challenging, he adds, because towers with malfunctioning lights can be hard to see in the darkness. Larvae missions are flown by day.

Wolf On The Wing

The Tampa Bay coastline in southern Hillsborough has long been one of the county's biggest mosquito havens because of its large patches of saltmarsh. In Apollo Beach, Ruskin and Gulf City, the county gets mosquito complaints through the winter, Hayes says.

"It really doesn't go away."

At Wolf Branch, the primary target is a fingernail-size critter with a big name: Ochlerotatus taeniorhynchus.

It's a species that flies by day and night. Long thought to be more of a pest than a killer, the insect has recently been the focus of studies to determine whether it carries West Nile virus because of cases that turned up in South Florida where the critter is prevalent, Hayes says.

He watches as inspector Ram Maistri accompanies helicopter pilot Mike Muench on a reconnaissance mission. Maistri returns with a plastic soda bottle bearing brown water taken from a makeshift marsh created by rain.

At the bottom of the bottle squirm dozens of tiny prisoners of war that unknowingly betrayed the position of their comrades.

Hayes and Maistri heave 40-pound bags of AquaBac 200G, one by one, to fill hoppers mounted on each side of the helicopter. Loaded with 400 pounds of ammo, Muench lifts off to sweep the hot spots, trailing a granular stream of bacteria-laden mosquito bait in a 60-foot swath behind him.

"The larvae feed on it," Hayes explains. "It eats their insides and their little belly explodes, and when it explodes, the bacteria goes back into the water" to kill more larvae.
Mosquito Control routinely samples areas prone to standing water and checks 70 traps a week across Hillsborough's 1,100 square miles to make sure employees know what species lurks where and to scout for new species. The county is home to at least 46 kinds of mosquitoes, Hayes says.

Nearly all of the department's 12 inspectors can identify a species from squashed remains on their arms, he says. Some department veterans can do fly-by identifications.

Employees use the information to develop treatment plans.

Last year, the helicopter logged about 300 hours on spray missions, and fogger trucks made about 500 trips, said department director Carlos Fernandes.

Department records show far more acreage - 194,000 last year - is treated for adults than for larvae, which accounted for about 11,000 acres during the same period.

But that's because larvae treatments target smaller pockets of wetland, Fernandes says.

Over time, he expects the emphasis on killing mosquitoes before they fly to pay off, along with an aggressive inspection program.

The $3 million-a-year mosquito program provided 25,000 inspections of ditches and other water-harboring spots last year, plus about 4,000 responses to residents' requests for home inspection or neighborhood treatment.

The department also treats hydrilla and water hyacinth that harbor mosquitoes.

Hayes doesn't expect to win the war on the prehistoric pests.

"Mosquitoes have been mosquitoes since the dinosaurs," he says. "We have job security."

PERSONAL MOSQUITO PREVENTION TIPS

• Don't allow standing water to create mosquito breeding grounds. Inspect your yard for stagnant water in tin cans, old tires and unused plastic wading pools, flower pots and pet dishes. Regularly rinse birdbaths and bromeliad plants, which can harbor larvae.

• If you're not using your swimming pool, cover it, but make sure the cover does not sag and hold pools of rain water. Residents may wish to introduce gambusia, or mosquito fish, in pools not being treated with chlorine. The fish are available from Mosquito Control by calling (813) 554-5029.

• Clean rain gutters, which can become clogged with leaves and hold enough water to support mosquito larvae.

• Mosquitoes are not strong fliers. If you must be outside at dusk, when mosquitoes are most prevalent, use a portable fan to keep them at bay. Also wear long sleeves and use a repellent containing DEET, but be sure to follow the application instructions on the label.

• Check your door and window screens periodically to make sure there are no holes where mosquitoes can get in.

Source: Hillsborough County Mosquito and Aquatic Weed Control Department MORE ONLINE

Go online to see more photos of how the county battles mosquitoes, keyword: Mosquito Chopper. Go online to see more photos of how the county battles mosquitoes, keyword: Mosquito Chopper. Reporter Susan M. Green can be reached at (813) 865-1566 or sgreen@

Share this:

Loading Comments...

Email Print

ADVERTISEMENT