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11 July 2003

Like a Banana?

by Dianna Hrabovsky, Treasurer of MAST

"Time flies like an arrow, Fruit flies like a banana" is a humorous pun unless you are plagued with an infestations of fruit flies. Fruit flies or drain flies can be a real annoyance in many homes and bars. These little pests seem to pop up and multiply like crazy with little cause or provocation. Side note to my husband George - You should introduce them to Calculus so they fly away in fear. Our home has been recently overtaken by the swarm, so I set out on my quest to get some answers on how to get rid of them. Ah ha!! Science will rid me of these pests!! Or so I hoped...

Even though fruit flies are harmless and don't carry diseases, it did not take me long to find an abundance of articles on the annoying part of the fruit fly problems. There were many articles on ways to kill fruit flies and even some on the concerned catch/release program for the little guys. It seems that a fruit fly likes fermented food and will breed anywhere there is moisture. Some will even breed in the drains thus gaining the name "drain flies". Garbage cans, sink drains, open bread bags, leaky pipes and of course fruit and vegetables that have been left out are all wonderful hosts for a batch of fruit flies. Bars can also be a good place to find infestations since they like the bar trays and sinks to live in and the abundant amounts of sugar, fermented beverages, and moisture to be found.

Well, time to find ways of sending these unwanted guests packing. My husband's not so reassuring words that they will never go away because we live next to an Arboretum did not deter me from my next course of action which I will entitle "Operation Bye Bye Fruit Fly".

Operation BBFF Science Experiment 1 - Which method of fruit fly extermination works best?

There seemed to be many suggested methods for reducing the unwanted flies to reasonable levels. None actually mentioned getting rid of them completely, but I decided to set up some of these on the edge of the sink and see which the flies liked best. These were the methods I tried:

Method 1 Placing vinegar or spoiled fermenting items into a bottle and putting a paper or metal disposable funnel into the top of the bottle. This would allow the flies to enter but supposedly get confused and not be able to get out. This was the preferred method for the catch/release idealists.

Method 2 A bowl or two as needed filled with 1/2 quart water, 2 Tablespoons sugar, 2 Tablespoons vinegar and a couple drops of dish soap.

Method 3 A bowl with some vinegar covered with plastic wrap. Small holes are punched into the plastic wrap to allow the flies in but not out.

Experimental Idea 4 Fungus gnats and fruit flies are supposedly attracted to the color yellow so as an interesting side experiment I decided to place a small piece of yellow paper beside the experiments to see if the flies would land on it or show any interest at all. This could be used to attract the flies to the trap if the color attracted them. This interesting fact prompted me to immediately check my Mt. Dew for unwanted guests.

One method not employed was just to suck them up with the vacuum cleaner. Another was to use a glass of red wine as the attractant or get a Sundew plant and let it eat them. Or, as my husband seems to gain the most pleasure and supposed stress relief out of, you can just smack them in or out of the air with your hand.

My findings Using a bowl of stale dish water as a "control" to make sure my flies were not just randomly suicidal, I watched the containers off and on to see which ones the fruit flies were attracted to. Much to my dismay I realized my experiment was flawed. The flies of course went to the easily accessible open dish with the vinegar, sugar and dish soap (Method 2) and merely sat on the outside of the other containers. After 2 hours there were 11 dead bodies in the Method 2 experiment but no more since. I think that they have posted signs on the dish now. After having watched their buddies go in and not come out, this seems to have prompted many of them to fly away or just stand on the edge in possible memorial. They also avoided the yellow paper. I am understandably dismayed but not defeated. My quest for the proper method will continue.

Some suggested methods for getting rid of "drain flies". The use of bleach, ammonia, or very hot water was suggested as a way to kill off the flies in the drains. Another way was to use cooking oil to coat the inside of the drain to temporarily stop the flies from breeding. The oil is said to float on the water and supposedly stops them from getting to the moisture. Since I do not have flies in my drains, these methods are only suggested methods I have run across and I have not tried any of them personally.

Semi-unrelated follow-up research It seems fruit flies are used in research to study medical conditions. Hopefully the medical conditions aren't psychological trauma caused by annoying pests. Anyway, humor aside, this seemed really interesting and I hope to share more information and facts about it.