Do fruit flies lay eggs?

Where fruit flies lay eggs in a house

Anywhere the larvae will have something to eat. Cornell puts it plainly: females lay eggs on the surface of food their larvae will later eat. The University of Kentucky says all that is needed is a moist film of fermenting material, which is why the list goes well past the fruit bowl.

Kentucky names drains, waste disposal units, empty bottles and cans, bins, mops and cleaning rags. Ohio State adds a few you would not think to check: an empty ketchup bottle, a sour mop or dishcloth, and the drain water inside a fridge. It also says a single rotten potato or onion can produce a heavy population on its own.

If you have binned the fruit and they are still coming, one of those is the reason. Finding where they are breeding in the house goes through the places to look, in the order worth checking them.

Do fruit flies lay eggs in fruit?

On it, and mostly on fruit that is already going over. The University of Kentucky's extension service says ordinary fruit flies are associated with damaged, overripe or rotting fruit and vegetables. A split banana skin or a bruised plum is the invitation.

There is one exception, and it lives in the garden rather than the kitchen. Spotted wing drosophila has a saw-like egg-laying organ, and the RHS says that, unlike native vinegar flies, it can damage ripe, unblemished fruit. It was first reported in Britain in 2012, and it goes for soft fruit still on the plant.

The eggs can also come home with the shopping. Cornell says fruit flies often come into your kitchen as eggs or larvae on store-bought and homegrown produce, which is why fruit flies seem to appear from nowhere.

Do fruit flies lay eggs on you?

No. A fruit fly lays where her larvae can feed, and Ohio State says they feed mainly on the yeast in fermenting liquid. Your skin is not that. I could not find a single official source that says fruit flies lay eggs on people, their hair or their clothes.

Ohio State also says they do not bite humans, so if something is biting you, it is something else. What is actually biting you covers the likely culprits.

Ohio State does note that some fruit fly species have caused intestinal myiasis, which means larvae in the gut, among vineyard workers. A 2023 case paper calls the gut an exceptional place to find them. Neither is a fly laying eggs on someone's skin. Whether to eat fruit the flies have been on is a separate question, answered in are fruit flies harmful.

Why cider vinegar pulls in the ones about to lay

Vinegar is diluted acetic acid, made by fermentation. A 2009 study in PNAS found that female fruit flies are attracted to food containing acetic acid as a place to lay their eggs. The odd part is that the same flies avoid sitting on it the rest of the time. They go onto it to lay.

So a cider vinegar trap smells like the best nursery in the room to exactly the flies you most want to catch. Why cider vinegar beats the other vinegars goes into the detail.

What the eggs mean for getting rid of them

Two jobs, and you need both. Ohio State says to concentrate on getting rid of the places they breed, and to put fruit and veg in the fridge before it starts to ferment. That deals with the eggs already laid. A trap deals with the adults, which stops the next batch. The full order of work is in how to get rid of fruit flies.

Eggs hatch in about a day, so flies keep turning up for a while after you have binned the source. How long fruit flies live has the timing, and why a few days of trapping is not the end of it.

One catch if you bait a trap with fruit. Cornell says the bait in a trap should be replaced every few days, to stop new larvae developing in it. A piece of ripe banana is exactly what a female wants to lay on, so swap it before it becomes the next source.