Aberdeen Mosquito Control’s war on mosquitoes.
Every summer, Aberdeen wages a never-ending war against droves and droves of the world’s smallest (and most annoying) hostile threat: mosquitoes. They invade our backyards, our gardens, and our parks, and quickly ruin many outdoor activities that take place past 7:00 PM. No matter how much we swat at them or spray ourselves down with DEET until our clothes become soggy, they always seem to come back with a vengeance. Thankfully, we can always count on Aberdeen Parks and Recreation’s Mosquito Control division to serve as our front line of defense to help keep our summer months relatively itch-free.
Aberdeen Mosquito Control has two primary functions: protecting the citizens and controlling nuisance mosquitoes. Their top priority is controlling vector mosquitoes, which are the mosquitoes capable of transmitting diseases. Right now, these are primarily Culex mosquitoes, the genus of the species that carry the West Nile disease. The second is to control the population of floodwater mosquitoes, which are the ones most prevalent in numbers, so that people can enjoy being outside without having to worry about pests. Although it’s impossible to eliminate them entirely, Mosquito Control’s goal is to keep these numbers at a manageable level so people don’t have to go ducking for cover every time they go outside.
In order to keep our streets safe, Mosquito Control operates under the Integrated Pest Management (IPM) program, which puts an emphasis on solving pest problems while minimizing risk factors to people and the environment. The foundation of this program starts with surveillance. Mosquito Control places traps throughout the community, which are then brought into labs where the trapped mosquitoes are counted and tested to see whether or not they are carrying West Nile.
Next, they do larviciding, which involves dipping pools of water to find larvae, counting how many are found, and observing what stage they are in before taking action. According to Park Superintendent and head of the Mosquito Control division Mark Hoven, this is one of the most effective methods they employ, because it gives them a good gauge of what’s coming and how they can treat it. “The best way to control them is to get them in the water,” he explained. “We have natural products that we put in the water that either control the growth hormone of the mosquitoes or take them out immediately depending on what stage they’re at.”
The traps are primarily used to determine when Mosquito Control has to go out and spray. When the trap numbers begin to rise or West Nile is spotted, they know it’s time to target adult mosquitoes with pesticide, called adulticide. However, Mosquito Control doesn’t spend as much time spraying as many people might think. “Those little white trucks and yellow lights are probably what people see the most, but that only makes up about 10% of our time,” Mark said. “Most of our time is spent in surveillance and larviciding in and out of the community to keep mosquitoes from harvesting.”
When spraying, Mosquito Control uses a pesticide called Permethrin that sprays only .007 ounces per acre. When people see the trucks coming down the sreet emitting fog, that’s actually just the carrier oil being produced that lifts the Permethrin up into the air. “We could put a thousand droplets on a pin; they are so small that the naked eye can’t see them,” Mark explained. “But there’s enough product in there that it will take mosquitoes out.” When targeting mosquitoes, Mosquito Control has to be careful not to take out any off targets such as beneficial insects. “That’s why we spray at night, because the beneficial insects aren’t flying actively.”
Mosquito Control employs seven part-time employees from mid-April to mid-October, most of which are college students with a background in biology or natural sciences. Everyone that applies has to obtain a Public Health Pesticide Applicator license, and is responsible for nearly every aspect of mosquito control, from conducting tests to identifying mosquitoes to using pesticides. Mark is responsible for everything else, including overseeing all operations, making executive decisions, and deciding which products to use. Although it can be hard work, Mark finds it to be very rewarding. “It was pretty interesting when I first got into it. It’s amazing when you’re battling an insect that outnumbers you a million to one.”
The biggest challenge Mosquito Control faces each year is without a doubt West Nile. The disease has been in Aberdeen for 13 years, meaning its return is inevitable, but it can be difficult to predict how much it’s going to rear its head. Depending on the weather conditions, the amount of cases each year varies drastically. Typically, the hot and dry years yield more cases of West Nile. “The Culex mosquitoes enjoy that really dirty, mucky water,” Mark explained. “That’s where they breed.”
The first cases of West Nile usually start showing up in the second week of June and slow down by the second to third week of August. Once a pool containing West Nile is detected, Mosquito Control picks up their efforts with spraying and works even harder to raise public awareness. They advise the public to do three things: dress, drain, and defend. People should start by dressing properly in the evenings and mornings when mosquitoes are active by wearing pants and long-sleeve shirts. It’s also advised that people go through their properties and look for any standing water that may be around, whether in gutters, on a boat tarp, or even in tiny bottle caps, and drain it. “That will breed thousands of mosquitoes,” Mark said. “If a mosquito can find its meal right there, it isn’t going to travel 5-10 miles to look for a blood meal, it’s going to find it in you.” Lastly, people can defend by using insect repellent whenever they go outside.
By taking these small steps to control mosquitoes on our private property, we keep the city as a whole safer as well. “A female mosquito lays 150 eggs every time. 75 are male and 75 are female. Those 75 go out looking for bloods meals, and they all lay 150 more eggs,” Mark said. “Every 3-4 days it turns around at thousands more mosquitoes. That’s why we tell people to take care of their property. If you have a lot of mosquitoes around you, you might be breeding the very problem.” // – Becca Simon