Latin: Drosophila
The banana fly is probably one of the most well-known pests in Denmark. It has a special ability to appear in spoiled fruit and vegetables with fermented odor in our homes. There are about 600 different species of the banana fly, all belonging to the group with the Latin name Drosophila. But fortunately, not all 600 species move into our homes. In fact, only a handful are found indoors.
The banana fly goes by many different names, which includes vinegar flies, fruit flies and wine flies. These names are not gripped out of thin air, but clearly indicate what type of food the banana flies prefer and are attracted to.
Appearance
The banana fly has a recognizable appearance. The fully grown banana fly is between 2 to 4 millimeters long and has a yellow-brown color. Its eyes are red or brown. It is first and foremost the flying style of the banana flies that makes them easily recognizable as they have an almost airy and hovering way of flying. The banana fly larvae are between 4 and 5 millimeters long and are small maggots that have a whitish-yellow color.
Biology and behavior
As described, banana flies are incredibly fond of fermented fruits and vegetables. They can travel far if they catch a deliciously fermented scent. This is also the reason why the banana flies are frequent guests in our kitchens, which can be a true paradise to them. Trash cans, bottles of wine and beer jars, open ketchup bottles and half-empty glasses of jam are just some of the many temptations that attract the banana fly.
The banana fly does not just eat these goods. The female also lays her small whitish eggs in these surroundings. The female can lay 25 eggs in one day, just as she can lay 200 eggs in total in her lifetime.
The female’s eggs take about a day to hatch. And out of the eggs come the small larvae that search down into their edible surroundings. The larvae then undergo their development from larva to adult banana fly. A process that lasts 4-5 days, after which they pupate. Inside the pupa – which roughly resembles a small brown seed – the process continues and the transformation into an adult fly is completed. This takes another 3-4 days.
The banana flies do not consider idleness as soon as they are fully grown. Already when they are 24 hours old, they start laying eggs themselves. If a banana fly has all the circumstances in its favor, it can go through its entire development – from being an egg itself to laying an egg – in just 10 days. Sheltered indoor areas provides the banana fly the best conditions.
Damage
As such, the banana flies do not harm us. But that does not mean they are pleasant to have indoors. Not least because their eggs are difficult to see with the naked eye, which is why they can easily breed in our foods without us noticing it.
Prevention and pest control
Prevention is without a doubt a great tool when it comes to banana flies. The banana fly is likely to be attracted from far away, and it is important to minimize all areas that can have an attractive effect on the banana flies.
You can advantageously store your food in a way, that minimize the banana fly’s opportunity to lay eggs in them. This is done, among other things, by ensuring that ketchup bottles, jams and other pickled foods are thoroughly sealed. Empty bottles with remains and the like should not be left for too long, just as you can be extra careful to empty the trash and the bag with organic material.
It is not only indoors that you can work a little proactively. Be sure to remove fallen fruit from the lawn as it can constitute a true breeding paradise for the banana flies. In addition, you should make sure that garbage cans and compost piles with waste are securely closed.
You can use a regular insect spray to fight the banana flies indoors. However, you should be aware that the effect can be short-termed, as there may be eggs around that you do not get rid of at the same time. Use the insect spray frequently when you are severely affected by infestation and combine it with preventative measures and general sanitation in the kitchen.
"Pests in House and Home"
"Bed Bugs - Bites, Stings and Itches"
"Food Pests"
"Husets dyreliv" (Insects Around the House - Only danish)
"Skadedyr i træ" (Timber Pests - Only danish)
"Stuefluen" (Common Housefly - Only danish)