Why do earthworms go on the sidewalks when it rains?
Why do earthworms appear on the soil surface when it rains?
Even if this is still matter of study and so there is no ultimate answer, experts agree on what is not the explanation: drowing! Indeed earthworms do not come to the surface to escape drowning since they are perfectly able to survive several days submerged completely in water (provided there is enough oxygen in it)!
As disappointed you might be, you have to know that probably earthworms come to the surface in rainy days just to walk much bigger distances than they can do underground.
They breath through their skin that must be wet in order to properly work, because of that, rainy days represent a good opportunity to move safely on the soil surface whereas in dry conditions they would dehydrate and die.
In a few words, earthworms like to be faster and they can only when it rains! :)
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