Hot Topics: Apartment Overrun by Flies

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Original Post: Apartment being overrun by small flies Please help!

Gary Ambrose Member

Hi everyone, long time member but possibly my first time posting. I was wondering if anyone can identify the fly I have posted a picture of. They are small. At first, I assumed they were fruit flies because of how small they were, but now I'm not sure. I don't think they are drain flies because I have never seen any come out of any of our drains. To me, they almost look like regular houseflies, only a lot smaller. The problem started a while back but it was not many so we weren't too concerned about it. We just killed them when we could. The numbers have grown greatly so it appears they are breeding, and it seems when the weather recently got warmer the population really exploded quickly. When it first started they were hanging out mostly in the kitchen and bathroom but now they are in every room throughout the house. I have taken to vacuuming them up several times a day but no matter how many I vacuum, there are always more. We are trying to avoid calling in a pest control expert because it is an expense we don't need right now. I have no idea where they could possibly be breeding. I figured the first step was to identify what type of fly they really are and then if anyone has any suggestions on how to deal with the problem, I would be eternally grateful! Thanks in advance.

Just wanted to post some additional information on their behavior, which doesn't match what I have learned about fruit flies in the research I have done. First, we almost NEVER have fruit in the house, and if we do it's in the refrigerator. The thing is they seem to hang out in areas where there is no food at all. They are just chilling on the bedroom wall. I know they are eating something, but I never see them eating, and we make every effort not to leave stuff out for them to eat.

A small fly in an apartment

PAbugman Forum Topic Moderator

Identifying flies from photos is difficult as close-up with details is required. I can see enough to know that I probably can't ID it anyway, as it's not one that I've commonly dealt with. You are very correct that proper ID of flies is paramount in order to control. Any reputable pest control company that you might call would have to ID them first. There often is not a pesticide solution to fly problems as when we find out what they are, that will lead us to where they are breeding and why.

Can you catch several specimens and take them, dead but not squashed, to your local county agricultural extension agent? Don't know what state you are in, but here in PA it would be the Penn State county extension office. They are usually run by a university. They are a good source of objective info — no sales job.

Keep us posted with what you find. I'm curious.

Gary Ambrose Member

Thanks for your reply. It looks like the local agricultural extension here in New York state is run by Cornell. I'll give them a call and ask if they have an insect expert that I can bring some dead flies to for them to identify. Hopefully they can. Thanks, I appreciate the suggestion. I hope I can figure out what these buggers are and get rid of them soon.

Gary Ambrose Member

So I finally got around to bringing a sample of several live flies down to the local agricultural extension office. They determined that it is a common fruit fly. I'm surprised because they don't seem to look like the photos I found of fruit flies. What would be the most likely breeding areas for fruit flies? I appreciate your time in answering my questions.

PAbugman Forum Topic Moderator

Sometimes species can vary in size, shape, and appearance from one geographical area to another. Maybe that's what happened here. The good news is now we know what they are.

I can recall several unusual incidents in which small flies, including fruit flies in one case, showed up inexplicably.

One time the man of the house opened the chest freezer and set a bag of frozen meat beside the freezer while he found what he wanted. He forgot it was there and it was out of sight. Eventually small flies showed up randomly inside this rather pristine and organized household. He eventually found the bag.

Another case was in another immaculate house with an unexplainable fruit fly problem. Long story short, it turned out that one of the small children, when they didn't like their dinner, would scrape it off into a tall vase/urn type thing in the living room.

A big culprit of fruit flies issues is, in fact, a vegetable: the common potato. It is not unusual for people to forget that they have potatoes in a bag hidden on the bottom shelf of the pantry, in the back.

Are you still seeing them mostly in the bedroom? Is it possible that there are canned goods in or near the bedroom? Sometimes an old can will leak, such as canned fruit or tomato sauce.

You've checked the obvious and common causes which is the way to begin. Now it may be time to get unconventional with your inspection. Keep us posted.

Gary Ambrose Member

PAbugman, thanks for your replies. Funny you should mention potatoes — recently we had a foul smell coming from the kitchen and after some time finally found a bag of potatoes that had been sitting there far too long and had rotted to the point they were starting to turn into a liquid. The thing is that the fly problem started long before we had those potatoes and they were sealed in a gallon size Ziploc bag. Plus, flies didn't really seem to hang out in the area where the bag was located.

The flies are not mostly located in the bedroom. They are mostly in the kitchen and bathroom. We are seeing some now traveling to other areas of the house, but the majority stay in the kitchen and bathroom (which happen to be located very close to each other).

I certainly wouldn't say the house is immaculate, but we do our best for having three kids and a dog and cat. I suppose it may be time for a top to bottom side to side cleaning of the house. As you say, they must be coming from somewhere. It's just surprising to me that they seem content to hang out on perfectly clean surfaces. That's why I was surprised when the agricultural extension office told me they were fruit flies. I would expect them to be constantly seeking out nourishment.

In any event, thank you for your help. I hope to get this figured out soon.

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