Fruit flies

You can hardly escape it in the summer, those small irritating flies that fly all around your fruit bowl. These small red-eyed insects are also called Drosophlidae with a Latin name. The fruit flies are a family of flies with great diversity that occur worldwide. There are dozens of subspecies for this fly. The best known species is the Drosophila melanogaster, or in Dutch the banana fly.

Species

There are a lot of species Drosphilidae, in total about 3000. The best known are, among others, the:

Banana Fly, the ‘common’ fruit fly

There are many types of fruit flies, but the banana fly is by far the most famous. This is because they are common in the Netherlands, but also because the banana fly has been used a lot in laboratory experiments.

Drosophila funebris

Another common species in the Benelux is the vinegar fly, the Drosophila funebris.

Suzuki’s fruit fly

This Asian species, the Drosophila suzukii was much in the news about 5 years ago because of the damage it caused to crops.

Drosophila hydei and virilis

Finally, you might also encounter the D. hydei and virilis. Just like the ‘regular’ fruit fly, these are often used as a source of food for animals such as lizards and prayer grasshoppers. These two species are slightly larger than the common fruit fly.

Habitat

The fruit fly originates from the tropical parts of western Africa. From Africa the fly has spread to just about every part of the world, except for the polar regions, where it cannot survive. Since about six to ten thousand years ago, the banana fly has been found in Asia and Europe. The fruit fly was taken by man on ships from Africa. This fly is excellent for propagation in isolated areas and could easily travel all over the world, as long as fruit or other fermenting organic substances are present.

Fruit flies in the UK

Because the fruit fly is such a good survivor, you will find this fly in abundance in the Netherlands. Especially in summer when it is nice and warm and when there is enough humidity, the fruit fly can propagate and spread all over the country.

Literary characteristics of fruit flies

What distinguishes a fruit fly from a normal fly is its size. Fruit flies are very small, the body length is about 2 to 3 millimeters. On average, the females are slightly larger than the males. Because of the long wings the little animal sometimes seems a little longer than it actually is.

Eye

Eye
The most striking thing about the fruit fly are the large, red eyes and the convex, curved thorax. The deep red eyes are relatively large for his body and consist of dozens of small subeyes. Between the eyes you will find microscopically small hairs. With his eyes the fruit fly can only see movements and changing shadows.

Thorax

The chestpiece of the fruit fly stands out because it is relatively large and spherical. At the top of the back there is a small scaly shield, the so-called scutellum. The chestpiece also wears thick black hairs. In between are again smaller hairs.

Comparable insects

The D. suzukii is a related species that is mainly known as a pest insect on fruit trees, different plants such as the tomato and different ornamental plants. There are about 3,000 species of fruit flies that all resemble each other, but can be very different in color.

Lifestyle

The fruit fly can survive in almost all circumstances, they do not occur only in the polar regions. They are also doing badly in a very severe drought. They can reproduce quickly, as long as there is enough food available. This makes the fruit fly also ideal for growing as food for insectivores such as scorpions or small lizards.

What do fruit flies eat?

As the name says, fruit flies mainly eat fruit. Their diet consists mainly of fermenting fluids and decaying fruit. The larvae of the fruit fly feed on bacteria and fungi. Under certain circumstances the fruit fly may also exhibit cannibalistic behaviour and eat its own species.

Fruit fly enemies

Because the fruit fly is so small, it suffers from many natural enemies. A wide range of insectivores has the fruit fly on its menu. Think of spiders, carnivorous beetles and larger, rotting flies. But even a cat, for example, can easily catch fruit flies. Because the fruit fly is so small, it is almost everywhere at the bottom of the food pyramid.

There are also specialized enemies, such as the parasitic wasp. This wasp species deposits an egg in the larva of the fruit fly. The wasp larva then eats the fruit fly larva from the inside out. A young wasp then emerges from the skin of the fruit fly. In this case, the fruit fly larva is dead.

Propagation & lifespan

At the fruit fly the males look for the females. Fruit flies can mate almost anywhere, even in confined spaces. The fruit fly starts as an egg, then goes through 3 larval stages, then becomes a pupa where eventually the adult fly hatch. This process takes about 2 weeks. Within a week this young fly can reproduce again.

In captivity a fruit fly can be up to 4 months old, in the wild this age is never reached. If there are a lot of flies in one place, the flies are constantly disturbed during mating and laying the eggs. The females become restless and lay fewer eggs. The flies also get less rest in between, so that the flies only have a life expectancy of 2 weeks.

Affection and diseases

It is certainly not hygienic to see all those fruit flies in your kitchen. Fortunately, the fruit fly is harmless to humans. They are mainly irritating, but not dangerous. Fruit flies are also vegetarian, so they cannot accidentally carry bacteria from man to man or from (raw) meat to man.
The fruit fly is also a nuisance for companies. It shall be present on premises processing or storing products containing fruit or yeast. The fruit fly will therefore be very popular around compost heaps, catering establishments, breweries and the retail trade, such as greengrocers and supermarkets. It goes without saying that you would rather not have fruit flies in the supermarket, then nobody buys the fruit any more.

Fruit flies control

Fighting can sometimes be difficult, especially in warm weather they can multiply at lightning speed. In the case of fruit flies, prevention is better than cure. In other words, throw away decaying fruit as soon as possible, keep your waste containers tightly closed, do not leave the dishes on the table for too long and do not allow fruit and vegetables to ripen in the kitchen. Do you want this anyway, and then make sure that you have covered it well with foil.

Do you already have them in your house? Then you can make a trap where you can lure them into. Take a bowl or bowl in which you do something they like, such as an overripe banana. Over the tray, stretch a foil with a small hole. They go into the bowl through the hole, but once in the bowl they can’t go back.

What also works is to place a receptacle with vinegar. Place vinegar in a receptacle together with a pump of soapy water/dew detergent. The flies want to drink vinegar, but die from the detergent.