Frequently Asked Questions

Q: Where is your schedule so I can determine when my house will be treated?
The District doesn’t have a schedule because treatment decisions are made daily. The Operations Department reviews surveillance data from throughout the District in the morning to determine if and where a treatment is needed. Residents can check our website for daily treatment map information or better yet, sign up to receive an advance notice when a treatment is planned that includes their address.

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Q: Where do you get the information for your surveillance data?
The District gathers data through mosquito traps, daily inspections by our Field Technicians, landing rate counts, and residents’ complaints. What is a landing rate count? A Field Technician stands in a specified location for 2-5 minutes and counts the number of mosquitoes that land on them.
Q: I sent in a mosquito report. When will I receive a mosquito treatment?
Citizens’ complaints are added to our surveillance data, but it doesn’t guarantee a treatment. If we see a pattern of increased mosquito populations in a large area, we will typically plan a treatment. Our Field Technicians are always happy to visit a homeowner’s property to investigate for mosquito habitat and apply a larval – or juvenile mosquito – control material to the affected area if needed.

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Q: Why are there so many mosquitoes here?
The combination of nearly year-round temperatures about 65°F and abundant water makes Southwest Florida desirable not only for residents, but for mosquitoes as well. Geographically, a large part of the Collier County is considered swamp land and provides the perfect habitat for mosquito breeding. In fact, more than 40 mosquito species have been identified in the area but only five of them are of great concern due to the diseases they can transmit to people. Those diseases include Dengue fever, West Nile virus, St. Louis Encephalitis, and Zika.

Learn more about our mosquitoes

Q: How does the District control mosquitoes?
The District follows integrated mosquito management (IMM) methods, which are endorsed by the Centers for Disease Control and the Environmental Protection Agency (EPA). These methods are scientifically based, comprehensive, and tailored to safely counter each stage of the mosquito life cycle. Controlling juvenile, or larval, mosquitoes through larvicide applications and reducing their breeding habitat is a prudent mosquito management alternative. When those measures are not clearly adequate, or if disease is present in mosquito populations, the application of materials to target adult, flying mosquitoes is used.
Q: What materials do you use to control mosquitoes?
The District uses three materials to control adult mosquitoes: Duet HD (a pyrethroid), Dibrom (naled), and Merus 3.0 (an organic pyrethroid). To control larval – or juvenile – mosquitoes found in water, the District uses a number of products containing either spinosad or Bti (Bacillus thuringiensis subspecies israelensis).

Find all the labels of the products used by the District

Q: How much material is applied during one of your treatments?
When the District applies control materials for adult, flying mosquitoes using airplanes or helicopters, the application systems on the ships use an Ultra-Low Volume (ULV) rate. Dispersed at an altitude of 300’ to treat the column of air above the ground, the ULV aerosol spray is almost invisible because of the extremely small droplet size. The droplets are measured at approximately 20-30 microns (e.g., one human hair is about 100 microns in width). Because of the tiny droplet size, rarely do any of the droplets make it to ground level. If any do land on the ground, the material quickly dissipates and leaves no residual effect.
Q: Does anyone oversee the use of the materials applied by the District?
Yes, all Florida mosquito control programs are established and operated according to the procedure given in the Mosquito Control Law, Chapter 388 Florida Statue (F.S) and the Mosquito Control Rules, Chapter 5E-1 3, Florida Administrative Code (F.A.C.) The Federal Insecticide, Fungicide and Rodenticide Act of 1972 (FIFRA) requires that the Environmental Protection Agency (EPA) be certain that all personnel handling hazardous or restricted chemicals be trained to do so correctly and safely and that they be certified as pesticide applicators.
Q: Do the District’s control materials cause cancer?
According to available research, residents are not in danger of contracting cancer from mosquito control materials applied infrequently and at low amounts. Most of the mosquito control materials are “non-restricted use” pesticides, which is the same category as the garden and household sprays you can purchase at the store.
Q: Will the materials affect people or pets? What if it is inhaled or if it lands on the skin?
Unless a person is very sensitive or allergic to chemicals, washing the skin with water is all that needs to be done. At the ultra-low amount of material applied by the District, no other symptoms should be experienced but individuals should consult a physician with their concerns.
Q: What should I do if I feel sick after one of your treatments in my area?
See a health care professional immediately! In Florida, if pesticide is found in a person’s blood, health care professionals are required to report the condition to the State Department of Health.
Q: What steps do I need to take to reduce exposure to the mosquito control treatments?
Generally, there is no need to relocate during mosquito control treatments. The control materials have been scientifically evaluated for this use and found to pose minimal risks to human health and the environment when used according to label directions. They have been registered by the EPA and reviewed by the State Department of Agricultural and Consumer Services for use around commercial, agricultural and residential areas. Although mosquito control pesticides pose low risks, we respect that some people may prefer to avoid or further minimize exposure. If this is the case, simply going indoors during the treatment will prevent exposure. Please be sure to sign up for advance notices of when your location will be treated; for example, when an evening treatment is planned, you will receive a notice earlier the same day.

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Q: How are mosquito larvae controlled in water?
Applying control materials to the water where juvenile, or larval, mosquitoes are present is an effective method of interrupting the mosquito life cycle. The District uses Bti (Bacillus thuringiensis subspecies israelensis) in either small granules about the size of kitty litter, in briquettes dropped in storm drains, or a mist application to those sources where mosquito eggs and larvae are found. Bti is harmless to people, animals, plants, fish and doesn’t affect water quality.

Learn more about Bti

Q: When you treat for mosquitoes, are other insects also killed?
The District strategically treats for adult mosquitoes after dark for a number of reasons, one of which is to avoid the control material coming into contact with other beneficial insects, such as bees and butterflies – they typically aren’t active at night. We use the materials strictly adhering to the labeling. These measures greatly reduce the chance of harming other insects.
Q: Mosquitoes love me, but not my partner. Why?
Mosquitoes let their sense of smell guide them to their meals, and some people just smell better to them than others. For example, if you walked into a house after someone had pulled freshly baked cookies out of the oven, you would be drawn to the smell and head toward the kitchen. A person’s aroma comes from many sources, including your genetics, breath, and the bacteria on your skin. Trying to mask it with perfumes or body lotions doesn’t generally help, and a tip: floral scents tend to draw in the pesky biters even more. Also, the notion of certain blood types being attractive has not been scientifically proven.
Q: What are the best mosquito repellents to use?
There are a number of EPA-registered alternatives available, including those containing DEET, oil of lemon eucalyptus, or picaridin. When EPA-approved repellents are applied properly and reapplied as needed, they are proven to be effective and will provide adequate protection.

Find the repellent best for you

Q: Does temperature affect mosquitoes?
Definitely! Mosquitoes thrive when it’s warm and when they have ample water where they can lay eggs. However, during cooler temperatures—below 65°F –they tend to stop reproducing and go into a hibernation-type of existence.
Q: What about bats? Should I put up a bat house to control mosquitoes at my house?
Scientific studies show that food items identified in a bat’s diet are primarily big, juicy beetles, wasps, and moths. Mosquitoes comprise less than 1% of a wild bat’s stomach contents in all studies to date. Bats tend to be opportunistic feeders –they do not appear to specialize on particular types of insects but will feed on whatever food source presents itself. A moth or June bug provides much more nutritional value per meal than a mosquito. There is no question that bats will eat mosquitoes, but to use them as the sole measure of control is not recommended. We wish bats (and dragonflies) alone could keep Collier County’s residents and visitors healthy and comfortable, but they simply can’t keep up with the sheer numbers of mosquito populations here.
Q: When does the District drop dragonflies?
This is a very popular local myth, and we cannot determine where it started. Each spring – when salt marsh mosquitoes emerge – we receive calls from residents requesting that we drop dragonflies. The District has never engaged in that activity, but it certainly makes us smile to think of the logistical challenges it would take to do so.

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