Editor's note: This article originally appeared in the July 2018 issue of PCT magazine.
A thorough inspection is key to solving any pest problem, and this is especially true when it comes to mosquitoes. With all due respect to Sir Arthur Conan Doyle, are you a ‘sure lock’ at investigating mosquito problems and providing reliable solutions to your customers? Read on for some valuable information and tips for battling these thirsty bloodsuckers.
NECESSARY TOOLS. All mosquitoes require water to complete their life cycle so most of your inspection will involve looking for and sampling water sources. At a minimum, have a mosquito dipper (available from most biological supply companies); a plastic turkey baster for getting into small areas; plastic, resealable bags for samples; a small metal or plastic pan for examining samples; and a good flashlight. The tools will not take up much room on your truck and they are very inexpensive.
INTERVIEW THE CUSTOMER. On your initial visit, interview the customer if possible. Ask about standing water sources on the property. Are people bitten mostly during the day, in the evening or both? Are there certain areas of the yard where mosquito biting is more intense? Are they bitten inside the house? Do they have an irrigation/sprinkler system? This interview will provide valuable information to help guide your inspection and subsequent treatments. Also, look around the yard for evidence of mosquito repellents, candles, torches and other things a customer may be using to ward off mosquitoes.
top breeding spots. Mosquitoes will breed in almost anything that can hold water, from a large, neglected swimming pool to something as small as a bottle cap, so take your time and examine the premises thoroughly. A partial list of common mosquito breeding sites includes tires, outdoor sinks, buckets, pet dishes, bird baths, bottles and cans, children’s toys, flower pots and drain saucers, tarps, leaky faucets, wheelbarrows, low spots holding water, decorative fountains that aren’t maintained and kiddie pools.
Not all mosquito breeding sites are obvious. Be sure to look for water-holding plants such as bromeliads. Although these may only hold a small amount of water, they can produce enormous numbers of mosquitoes! Open and examine any in-ground drains for sprinkler and irrigation systems. Check corrugated plastic tubes used to draw water away from downspouts — frequently the ends of these tip up or curl and hold water. And don’t forget to look up during your inspection! Clogged gutters and tree holes are often the culprits. Also, while you are inspecting the premises, take note of any mosquitoes that may be attempting to bite you!
TAKE SAMPLES. Sometimes, mosquito larvae and pupae (the immature stages) can be easily seen where they are breeding, such as in a bucket or plastic bottle. Other times they may not be so obvious. For larger bodies of water, use the plastic dipper for sampling, focusing on the surface of the water. For smaller spaces such as tree holes or plants, use the turkey baster to suck the water out. Dump the water into your plastic or metal pan (a light background works best) and look for the wigglers and tumblers. Tapping the side of the pan with your baster or finger will cause the mosquitoes to move around, making them easier to see. If you choose to preserve any samples, simply dump the water and mosquitoes into one of the resealable bags.
Be advised that mosquito larvae and pupae are very sensitive to shadows and vibrations. If you cast a shadow over the breeding site or disturb it prior to sampling, the mosquitoes will dive below the surface of the water, where they can remain for a minute or so. Therefore, you may have to wait a short time before taking your sample.
SHOW THE CUSTOMER. One of the most effective tools in your arsenal can be to show the customer the mosquitoes that you found as well as the breeding sites. Explain why the site is producing mosquitoes, what the different mosquito life stages are, and what, if anything, the customer can do about it. If you plan to treat any sites with larvicide or an insect growth regulator (IGR), explain that as well. Frequently, the customer may say something like ‘so, THAT’S what they look like. I always wondered what those were’ and they may then lead you to other breeding sites on the property that you didn’t find.
DON’T FORGET EXCLUSiON. Examine the structure(s) for mosquito entry points, especially if people are being bitten indoors. Look for torn or missing screens, broken windows, and doors that may be left open, propped open or don’t fit tightly. Mosquitoes will find their way inside buildings through the smallest of spaces! Also, some kinds of mosquitoes are highly attracted to light, so a change in lighting scheme may help.
INSPECT ON EVERY VISIT. Under ideal conditions, mosquitoes can complete their life cycle in as little as 5-7 days. Therefore, if you only visit the property every 30 days or so, you may encounter several new or previously undetected breeding sites and there may be adult mosquitoes on the loose. Hopefully, if you have properly educated your customer, some of these sites will be emptied before you arrive. Regardless, take the time on every visit to do another thorough inspection of the property.
IN SUMMARY. Now that you have successfully found the breeding sites on your customer’s property, you can make decisions on which sources to dump or drain and which ones may need to be treated. However, do not dump or drain any water without first asking the customer, and always read and follow the label on any product you choose to use. It can also be useful to make a quick map of the property, showing where the breeding sites and any conducive conditions were for future reference.
What if you can’t find any mosquito breeding on the customer’s property, yet they are still having a mosquito problem? This is common due to the fact that some kinds of mosquitoes will fly significant distances, up to perhaps 40 miles, from their breeding sites before they feed. So, you may not be able to do anything about the breeding sites but you can offer a service to control the adult mosquitoes. And, it is always a good idea to explain situations like this to the customer.
Finally, remember that without a thorough inspection for mosquito breeding sites on each visit, your mosquito control service is likely to fail, resulting in callbacks, unhappy customers and cancellations. So, look hard and look often!
The author is vice president of technical products and services at AP&G (Catchmaster), and can be contacted at firstname.lastname@example.org.