When it rains, most people immediately think of the ducks and birds who will inevitably come out looking for food, drier ground, and shelter. But what about those pesky flies? Where do they go when it rains?
The truth is that flies aren’t necessarily fleeing the rain. While the sound of rain may act as a stimuli telling them it’s time to hide in the shelter of a home, the rain itself probably won’t hurt them. In fact, many species of flies seem to thrive in wetter conditions.
What they’re actually running away from (besides us!) during the rain are the newly created puddles. Rain can cause the standing water already present in the environment to mix with each other, forming new pools that invite mosquito larvae to lay their eggs. This welcomes those pesky mosquitoes, which can introduce a host of health issues for humans. Flies, in an effort to protect themselves from their new predatory competition, may try to seek shelter in our homes.
That’s not all though. Flies are subject to many of the same pressures that humans experience from weather conditions, including changes in humidity, pressure and temperature. While we may seek shelter indoors from the cold, a fly does the same in order to protect itself from the heat. In fact, a fly’s body temperature can vary by as much as 8°F between summer and winter, in an effort to keep itself protected from temperature changes.
In addition to the temperature changes they experience, flies may also be driven indoors by changing wind patterns. When it rains, the wind can still blow, affecting the environment in ways that may force flies to seek protection and shelter inside our homes. This is especially true before, during and after thunderstorms, when wind speeds can be higher.
So, while the rain may not bother them, flies may seek out the warmth of our homes and other sheltered areas during periods of rain. They may also use this time to reproduce and feed, taking advantage of our distraction with the weather outside and the humidity inside, which are both conducive for fly mating and feeding. Hopefully, this answers the question “Where do flies go when it rains?” However, if you find the answer less than satisfactory, you can always try chasing them outside.