We’ve had occasional problems in the past with fruit flies in our house. This year, so far so good until a couple of days ago when we suddenly seemed to be overrun with fruit flies everywhere. My wife has been canning some fruits and the flies keep getting into the jars – it’s a mess. Where do these nasty little gnats come from? J. B., Exeter, NH

You provided a big clue in your question. I believe your answer is the ripe fruit that your wife acquired for her canning project. My guess is she bought a bunch of ripe fruit at a farmer’s market, or maybe it came from your own yard. Whatever the source, it no doubt came with fruit fly maggots already present. It doesn’t take long for adult flies to emerge.

TINY MAGGOTS IN YOUR PEACHES!

The female fruit fly (Drosophila spp.) lays her eggs in semiliquid, fermenting or vinegary foods, and is especially fond of overripe fruits and vegetables. In fact, once the produce really starts to rot, the flies are less interested since it becomes less desirable as a food source for the larvae (maggots). Larvae feed in the food material for a few days, then crawl away to pupate, and adult flies emerge shortly after. In warm weather, fruit flies can complete an entire life cycle in only 8-10 days!

The good news is that once the infested fruit or other material is found and removed, the flies should disappear as long as there is no other food source for egg laying or for larval development.

FRUIT FLIES AREN’T JUST IN FRUIT

The bad news is that fruit fly larvae can feed and develop in many other sites (see “Where Are These Fruit Flies Coming From?”) All they need is semi-moist, scummy, organic material for the larvae to feed on. A dirty garbage can, a slimy drip pan, or even a dirty drain can be a breeding source for fruit flies. When we have a chronic, ongoing fruit fly problem, we know we are going to have to look beyond ripe produce.

In heavy infestations, we can spray to kill the adult flies and can leave fruit fly traps, but unless the food source, or sources, are found, new flies will continue to develop. Give Colonial a call and have our experts inspect your home for fruit fly breeding sites.

Photo Credit : By André Karwath aka Aka – Own work, CC BY-SA 2.5, Link