Scare Flies Away With Water With This Chic Version of the Popular Latin American Bug Repellent

A plastic water bag hanging from the ceiling to repel flies.

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If you walk the streets of Latin America, especially rural or crowded places with food where flies love to hang out, you're going to see a lot of transparent bags and plastic bottles hanging from strings. This is a popular street invention to scare flies away, not chosen for its sustainable benefits (DIY, zero toxic) but for its cheapness.

Mexican designer based in The Netherlands Jose de la O took this idea and made a chic version of the thing: a glass lightbulb-shaped container that is filled with water and hanged from a neater string. How, you wonder, does this work scaring flies away? It's actually very simple.

Being an easy prey with poor defense skills, flies are not happy being around too much movement --a sign they can interpret as the proximity of a predator. So the water in bags and bottles acts as an amplifier of reflections, movements and colors to the flies' eyes, which scare them away.

Even if not widespread in the north, apparently the practice has been implemented in some areas, as highlighted by LifeHacker some time ago.

Another common local belief related to water in containers --in Argentina at least; is that placing a water bottle next to a tree will prevent a dog from doing its needs there, though that measure has not proven as effective as the fly antidote.

Whether the sleek version by Jose de la O, or the popular version that you can DIY at home, this repellent is far more sustainable than those filled with toxic chemicals, packed inside metal aerosol tubes or funny smelling creams. And useful tip to implement when camping if you're annoyed by the little fellas.