As temperatures dip below freezing, an unusually difficult mosquito season comes to an end. The Moab Mosquito Abatement District board members are considering the district’s future needs as they pursue a possible tax increase and seek a new manager.

Meanwhile, some residents have expressed concerns about how the abatement district used a chemical spray over the past few months, including the lack of a reliable notification system to alert residents when spraying was to occur.


Moab Mosquito Abatement District board member Mike Binyon said the district will no longer be spraying with Biomist 4+4 to control local mosquito populations, including Aedes aegypti, a species of mosquito recently discovered in Moab that can spread serious diseases such as yellow fever and Zika virus—at least for now.

“Unless something untoward happens, we’re not going to be doing any more spraying this year,” Binyon said. “We are continuing with our fieldwork…checking mosquito populations and checking our ponds.”

Binyon said the abatement district continues to be short on field workers, which constrains the district’s capacity.

“It’s really difficult to hire people for this job,” Binyon said. “It’s nine months out of the year and people have to be trained to do it.”

In addition, the district is now seeking a new manager. The former manager, Libby Nance, was

removed from the position on Oct. 12 after a tenure that included at least one attempt to resign and Nance repeatedly apologizing in a July public meeting for failure to control the local mosquito population.

Binyon said that Shanon Amsberry, the head of the district’s field operation, is serving as the manager in the interim.

Binyon said that, as with the field worker position, finding a manager for the Moab district is difficult due to the need for specialized knowledge related to mosquitoes in addition to the ability to budget and manage personnel, tasks that in larger districts are divided between several people.

“It’s a pretty complicated job for a very small district,” he said.

On Oct. 15, the Grand County Council voted unanimously to approve the abatement district’s noticing of up to an $80,000 property tax increase for 2020, representing an approximate 33.46% increase above the current property tax revenue budget. The resolution notes that property taxes are the predominant revenue source for the district, and council approval is only one step in the tax increase process, which will include mailing parcel-specific notices and holding a public hearing, which is scheduled for Dec. 2.


The current halt on spraying is welcomed by some residents who have been concerned about the abatement district’s frequent use of Biomist 4+4. While the product is labeled as “highly toxic to bees exposed to direct treatment on blooming crops or weeds” and “extremely toxic to aquatic organisms, including fish and invertebrates,” it is considered safe for use in residential areas, though both the abatement district and the Southeast Utah Health Department have issued recommendations to homeowners on the path of the spraying to turn off their swamp coolers and close their windows while spraying is taking place.

Local resident Jon Olschewski said his family—including a newborn—endured dozens of “sweltering nights” this summer because they kept their swamp cooler turned off and windows closed per officials’ recommendations.

At first, Olschewski said, he was glad the spray was noticeably reducing the mosquito population. But as the spraying continued, Olschewski became increasingly concerned about impacts on non-target species like amphibians, birds, dragonflies and bats—as well as the health of his family and especially his newborn child.

Olschewski said that as an organic gardener he is familiar with the chemical, and while he realizes the amount sprayed each time was minute, he questioned the cumulative effects of repeated exposure.

“Organic or not, it’s poison…You can’t trade one public health hazard for another.”

He said that Nance told him this summer, contrary to recommendations, it was such a small amount being sprayed that he did not need to shut off the swamp cooler.

“But whatever is outside is getting sucked in,” Olschewski said, adding that he could smell and even taste the spray in the air outside his home after the spray truck had gone by.

Olschewski also cited lack of notification as a problem, as he had no way to know if the swamp cooler was off when it didn’t need to be, or if there were nights they should have turned it off but did not. He said he spoke to Nance about it, suggesting the district start a Facebook page. Shortly after that conversation, he said, an abatement district Facebook page was created, but the spraying schedule was not posted on it. Olschewski said he never heard about the alerts available through the Grand County website. He said the abatement district should notify residents on the spray path with a door hanger notification including information on how to receive alerts.

“No one really knows how much (Biomist) they used this year,” Olschewski said. “We have a right to know…They need to be a lot more together before they start administering aerial poison in this town.”


Ary Faraji is the Executive Director / Entomologist of the Salt Lake City Mosquito Abatement District and helped write the American Mosquito Control Association’s manual titled “Best Practices for Integrated Mosquito Management.” He came to Moab to assist the Moab abatement district in mosquito control efforts after the species Aedes aegypti were found. He had words of reassurance for Moab residents on the safety of Biomist 4+4.

“The adulticides that we utilize have all undergone a tremendously scrutinous process by the (Environmental Protection Agency),” he said. “They undergo rigorous biological monitoring and evaluations to ensure that they are safe and do not have adverse environmental or public health impacts. The rates and methods at which we apply the products ensure maximum safety for humans, pets, wildlife, and non-target organisms. We would not be utilizing these control options if we were not confident in any aspect of their use.”

Faraji said he is “an entomologist by passion, not just profession” and “an avid environmentalist.”

“These adulticides are a last resort for us, but they are well justified, particularly in this case,” he said, referring to using adulticide to control Aedes aegypti.

“If these mosquitoes become established, it is not unlikely for a human traveler to visit the area with an exotic arbovirus, and pass on that pathogen to a local mosquito, which can then start a transmission cycle,” he said. “Aedes aegypti is an efficient vector of many different arboviral diseases, including Dengue, Yellow Fever, Chikungunya, and Zika virus. Why take that chance?”

Grand County’s bee inspector, Jerry Shue, said that while he had no way to know the impact of the spraying on the local insect population in general, it did not appear to him to have impacted Moab’s beehives.

“I personally did not detect any problems,” he said, adding that he keeps hives “almost at ground zero” of where the spraying occurred.

Changes ahead for mosquito abatement district, residents concerned about last season

“It’s a pretty complicated job for a very small district.”

– Mike Binyon