Jun 15, 2011 – Flies Are On Spring Break

QUESTION:

I do a lot of commercial hotels that have flies around the beach area and food areas as well. I am using masterline bifenthrin 7.9 to spray ground areas and shrubbery. We use fly bait boxes with golden malrin in food areas, gold sticks inside, vector uv traps on walls. Other than zappers outside what else can you suggest? areas are cleaned as well and we spray two times a week all over. Any ideas please? There is no standing fresh water around either.

ANSWER:

Fly management is a huge challenge, particularly when the problem is outdoors. If all you are dealing with is interior problems you can rely heavily on exclusion, UV traps placed liberally inside, perhaps pyrethrum misting devices over doorways, as well as good sanitation indoors to eliminate all chances of fly breeding inside. But, outside you are facing flies that are attracted to the area because of all the wonderful food smells that come from these food courts and restaurants, and in your area in the Caribbean there likely is a lot of outdoor dining. The demand from your customer likely is to provide 100% elimination of adult flies, which of course is impossible, but nonetheless you need to try for that goal. To come anywhere close to it you need to throw every possible weapon at the flies.

The arsenal for fly management must include NON-chemical steps as well, so we'll investigate IPM in a moment. There are fly traps of various kinds, fly baits of several kinds, and chemical applications of several kinds. The traps definitely capture and kill thousands of flies, but by themselves will never eliminate the overall problem. However, along with the other steps traps are one more important part, so these can be placed liberally in all areas, but keeping in mind that they are visible and often not very aesthetic to look at , so you wouldn't necessarily want a hanging bag trap full of dead flies in the dining areas. These may be better in service entry areas or around waste cans outside. The Gold Sticks and other hanging sticky traps are the same - they help to reduce adult fly numbers and can be important tools, but placed where they are appropriate. One of the failures in fly management is the use of TOO FEW devices like these, so the customer needs to accept the difficulty in total fly control and understand that your service comes at a price that is profitable to you.

UV light traps are best used indoors where competition from sunlight is minimal. But, in outdoor dining areas they can be helpful when placed properly, which is best between 1 and 5 feet off the floor. This seems to be the best "fly flying zone", and most likely to get the fly's attention. However, the tendency is to put the UV traps WAAAAYYYYY up high on walls, and preferably behind some plants or partitions so people don't see them, but then the flies won't see them either. Use a trap that is attractive and looks more like mood lighting and the customer should have no problem with it. Also, use a LOT of UV traps to increase the chances that the flies will see them quickly and be captured before annoying too many patrons.

Fly baits are excellent, but also consider the paint-on / spray-on Maxforce baits that can be applied to surfaces where the flies are gathering. You could also use the Quikstrike fly bait strips in areas such as the service areas or waste areas where customers do not see them. Other granular fly baits in stations also are effective. Consider applying residual insecticides onto surfaces such as walls, fences, tree trunks, etc. where you see adult flies resting. These will work for a couple of weeks, and products such as wettable powders and microencapsulated formulations may work better than other kinds of concentrates.

Finally, IPM - have you done a thorough inspection (let's call it a Sanitation Inspection) of these properties, inside and outside, to identify all those circumstances that are present that may be encouraging the fly problems. This includes dirty waste containers and waste can areas, spilled foods in dining areas, piles of vegetation that is decomposing, unnecessary wet areas, etc. Anything you can do to remove attractions that are drawing the flies will be a huge help in your other steps. Are the employees doing a good job of keeping doors closed and windows screened? Everything you can do non-chemically will be a long lasting control technique that should help reduce your reliance on all those other chemicals and traps.

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