Changes to county mosquito control program in the works

County may help fund study

The Gunnison County Board of Commissioners received some recommendations for its mosquito control program this week specifically designed to mitigate the effects of spraying for mosquitoes on area water bodies and Stonefly populations. And while the measures have already been added to the county’s contract with Colorado Mosquito Control (CMC), which conducts the spraying, some of the board seemed reluctant to take input from citizens who would like to see the practice stopped altogether.

Stoneflies are considered an indicator species, providing a measurement of overall ecosystem health. Last summer a large die-off of the stonefly Classenia sabulosa coincided with annual spraying of a Permethrin-based “adulticide”, and prompted a packed house to raise concerns at the county courthouse last December during the program’s annual review.
At the time, CMC manager Chris Kruthaupt said, “I suspect the fact that we sprayed in the evening and had a new operator may have exacerbated the problem.” The new operator flew a different plane and at a different altitude than past operators.
Kruthaupt joined county wildlife coordinator Jim Cochran and representatives from Colorado Parks and Wildlife, the Colorado State University extension office, and Western State Colorado University (WSCU) to provide recommendations to mitigate the effects of spraying.
The group recommended three practices, the first of which was to ensure that mosquito control chemicals be applied strictly according to the product label. “That sounds relatively simple until you read the label, and there’s lots of requirements. Some are recommendations and some are requirements,” Cochran said.
He explained that the label addresses temperature, wind, spray droplet size and other factors that can affect the reach of the chemical. Ideally, he said, applied correctly it should kill the insects in the air and never reach the ground.
The group also recommended that aerial spray equipment calibration data and GPS flight logs be provided to the county, and that the county consider supporting studies proposed for this summer to understand the impacts of spraying on water bodies.
Dr. Kevin Alexander, a professor of biology at WSCU who served on the review committee, has proposed a study of macro-invertebrates in the Gunnison River, Tomichi Creek and Ohio Creek before, during and after spraying. Colorado Parks and Wildlife is also considering additional studies that would look at the longer-term impacts of Permethrin on invertebrates and fish.
“We’re definitely supportive of what Western is doing in their research,” said wildlife manager J Wenum. “We looked into assisting on some of that, including analysis of water samples but the equipment we have right now won’t meet the tolerances and specifics needed for what Kevin wants to pursue.”
Instead, the agency could conduct those supplemental studies. Current estimates suggest that the WSCU study would cost about $7,600 and the Parks and Wildlife Study would come in at around $11,000. Parks and Wildlife officials think they’ve found funding sources for about half of their portion, and it’s possible that when both studies are considered as a whole further savings could be found.
“If we put these studies together, it would be a really good assessment,” Cochran said.
But that didn’t sit well with some members of the audience, who asked to give input when commissioner Paula Swenson started to close the work session without seeking public input.
Chris Madison, president of the local chapter of Trout Unlimited, asked if the committee had considered not spraying at all. “I heard that the discussion group was told to not even consider not aerial spraying,” he said.
County manager Matthew Birnie explained that, according to direction from the board, the “charge to the group was to find ways to mitigate the impacts of the spraying program.”
“So why wasn’t the study group allowed to at least consider not spraying all together?” Madison asked.
“They could consider whatever they wanted… but we weren’t designating county policy to this group,” Birnie said.
When Madison continued to ask for answers, both Birnie and commissioner Paula Swenson cut him off, saying that concerns about West Nile virus and previous conversations with the public had already addressed the need to control mosquito populations.
Ben Furimsky, a local fly fishing guide, said he had been unable to attend earlier meetings and wanted the commissioners to know that he had felt mist from spraying three times while fishing in local rivers. He also questioned the cost of the program.
“Right now we spend over $68,000 to kill 11 hours of adult insects so what about the next morning when they hatch? And the next?”
Commissioner Swenson tried to end the meeting, saying “This is going to be the end of this conversation because we’ve had this conversation numerous times at this table and in our community.” She pointed out that concerns about spraying would be addressed through the review committee’s recommendation and by conducting further studies.
But Furimsky wanted to know why the commissioners felt the need to wait for further studies on Permethrin. He cited several, including one from the Environmental Protection Agency (EPA), that show Permethrin is toxic. According to documentation from the EPA, the chemical a “restricted use” pesticide because of its high toxicity to aquatic organisms, except for wide-area mosquito adulticides.
“Why can’t we learn from other studies?” he asked. “They’re done. Are we so simple minded that we can’t learn from someone else?”
He went on to question why the proposed studies intend to focus on moving water, like rivers and irrigation water, when mosquitoes breed in stagnant manmade water. He started to list other facts about mosquitoes and the West Nile, but Birnie cut him off.
“We know all this, so what’s your point?” he said, adding that public health officials had addressed West Nile at earlier meetings. He said, “As for feeling spray that’s why we’re doing the study and getting data.”
“I am closing this meeting because there is no new information,” Swenson said. One week later the commissioners approved a renewed contract with CMC that allocates approximately $82,550 per year for the program. There is an exit clause should a Permetrhrin study lead to further changes in mosquito control practices.