Spraying to target Mosquito Flats pests

The area of Columbia Falls named Mosquito Flats came by its name naturally and in this near-record mosquito population year, it’s definitely living up to its name.

The multitude of mosquitoes in Columbia Falls this summer is making it unpleasant for people to spend much time outside, City Manager Susan Nicosia said. So, after much discussion, City Council members asked the county Mosquito Control Board to spray to kill adult mosquitoes.

Nicosia emphasized it won’t be aerial spraying and it won’t be blanket spraying in Columbia Falls. Rather, a sprayer mounted on a truck will spray in the River’s Edge Park neighborhood.

Initially, just one spraying is planned, county mosquito program Manager Bruce Gunderson said. The tentative plan had been to spray earlier this week, he said, but only if there were optimal weather conditions. Those conditions include a light wind (between 5 and 7 mph), and no rain in the forecast. Because those conditions haven’t existed, spraying hasn’t yet occurred.

Gunderson has talked with many people who live around the park, telling them about the spraying. “I didn’t hear any objections,” he said.

He plans to spray permethrin, which has been deemed the least toxic of the adulticides (chemicals targeting adult insects).

“It’s far safer than malathion,” Gunderson said.

While the Mosquito Board has adopted an integrated mosquito management system that includes using adulticides, the typical approach in Flathead County has been to use larvacides to kill immature mosquitoes. Employees place larvacide along river banks and on the shores of ponds.

But this year, some of that work couldn’t occur because river levels have stayed so high, Gunderson said. Employees can’t walk along river banks that are sloughing off and place larvacide, he said. And constantly changing river levels can result in too much of the larvacide placed at a high-running river simply washing away.

“So along the rivers this year our efforts didn’t bear much fruit,” he said.

“This is a particularly bad year,” Nicosia said. Council members came to realize that in this instance, the only way to reduce and control the number of mosquitoes was to spray, she said.

“Spraying is basically our last resort,” she said. She and council members realized that due to the unusually wet spring, county employees weren’t able to place as much larvacide as they do in other years.

That has resulted in the mosquito problem becoming “unbearable and preventing even regular outdoor activities,” she said. “They are a nuisance and it makes it difficult to even go outside.”

Gunderson said the Mosquito Board gave careful consideration to the Columbia Falls request. “It was a very thoughtful request and a very hard decision for the board,” he said. “But when other efforts fail, you still have to do something.”

Thirteen species of mosquitoes live in Flathead County, Gunderson said. Two of them, which constitute 2 percent of the county’s mosquito population, are capable of carrying the West Nile virus.

Reporter Shelley Ridenour may be reached at 758-4439 or sridenour@dailyinterlake.com.