New bug kill program awaits refuge

By Steve Estes

Plans to deploy ATVs for mosquito-fighting efforts in human/wildlife interface areas on Big Pine Key await a determination from officials at the National Key Deer Refuge on the environmental impacts of the proposal.

Florida Keys Mosquito Control District Executive Director Michael Doyle broached the plan last year as a means to better protect homes in the heavily wooded areas of Big Pine Key, as well as other similar areas, from the effects of the mosquito population.

The plan called for the use of all-terrain vehicles with mounted sprayers lining the foliage around heavily wooded properties with a surface insecticide.

The thought was that the bugs wouldn’t cross the line of foliage, or die trying, and better protect the homes in heavily wooded areas from the biting insects.

Doyle said the premise has been tried out in Key Largo using some private properties where only owner permission is required.

“The plan seemed to work well, but we did meet with some resistance from groups concerned about endangered butterflies. We have the same issue on Big Pine, which is why we’re coordinating with the refuge,” said Doyle.

He had hoped to have the program in place by the start of rainy season this year, but that probably won’t happen.

“We want to find three locations that suit the criteria we need and use those as a test for Big Pine to determine the actual effects of the procedure,” said Doyle.

What the district has been doing, he said, is concentrating efforts on the offshore islands that surround Big Pine and other areas with similar characteristics.

“Probably 70 percent or more of the adult mosquitoes that would make their way to Big Pine Key come from the wet areas on the offshore islands,” said Doyle. “By killing them there before they hatch we are better able to control the eventual population that makes its way to the more densely populated areas.”

The district is using large-scale larvacide drops from helicopters to unload the granular insecticide that gets in the standing water that breeds mosquitoes and kills the bugs before they can hatch and become airborne adults.

“Based on the data we have, there are about 80 percent fewer mosquitoes making their way to Big Pine now than 10 years ago,” he said.

And with the rainy months of May, June and July on the horizon, local residents should notice the difference in the numbers of bites they receive while outdoors.

Large-scale larvaciding has made it possible for the district to cut back on the more expensive and less effective aerial spraying for adult mosquitoes, said Doyle.

The ATV program may possibly make aerial spraying, which is a bone of contention between mosquito control and the refuge, which is charged with the protection of endangered species on federal lands, even less necessary.

“It’s the choice between placing a larger amount of insecticide in a smaller, more targeted area, or a larger amount, greatly diluted, of aerial insecticide in a much larger area,” said Doyle.

The district has all but grounded the truck-mounted spraying operation for Big Pine and similar areas.

“If we get bite counts three times normal in an area we are required by state law to spray,” said Doyle. “But we are barred by federal regulation from spraying in certain areas where endangered species that could be susceptible to the insecticide are found.”

Because more than 65 percent of Big Pine Key is in public ownership, with much of that refuge lands, “We can’t even open the spray valve on some streets because we don’t have a 50-foot swath to use.”

At a recent symposium of district employees and members of the public, Doyle unveiled some other, more radical ideas that might help with the control of mosquitoes in the future.

One of those ideas, broached by some employees, was to use insecticide launched from paintball-type guns into areas where standing pools exist but crews can’t easily reach them.

“Right now there is no product that can be launched in that fashion. We have opened a dialogue with some of our suppliers about developing such a system, but the $3 million or so in research it will take must be backed up by enough market to make it economically viable,” said Doyle.

“It’s a unique idea and maybe down the road someone will invest the time and effort into the research, but it’s not something we can deploy anytime in the near future,” he added.

As it stands, for those hard-to-reach areas where mosquitoes may breed, field inspectors have to get as close as they can and throw the granules by hand.

“Depending on wind conditions, that may add six or eight feet, but it’s not the most effective way to do things,” he added.

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