Many times, when there is rain after a long time, snails come out afterwards, and you can see snails and slugs everywhere! I have two questions:

  1. Why do they come out after the rain?

  2. Where are they usually found, not after a rain?

Note that I do emphasize when there is a rain "after a long time"

  • 3
    $\begingroup$ They probably need oxygen. If they are living in the dirt, then the water will force them to the surface. $\endgroup$
    – AMR
    Nov 2 '15 at 0:19
  • 1
    $\begingroup$ A yahoo answer post suggest that they come out to flee drowning as @AMR suggested. $\endgroup$
    – Remi.b
    Nov 2 '15 at 0:52
  • 2
    $\begingroup$ Snail Behavior Rain... 20,400 results; Snail Locomotion Rain 4,520 results; Snail Movement Rain... 22,500 results. $\endgroup$
    – AMR
    Nov 2 '15 at 4:23
  • $\begingroup$ chat.stackexchange.com/transcript/message/25100934#25100934 $\endgroup$
    – AMR
    Nov 2 '15 at 7:08

Snails are similar to amphibians in that they breathe through their skin (though they also have gills or lungs). Under dry conditions, they seek cover to combat dessication. But when it rains, they "come out," just like many amphibians.

I should qualify the first sentence to say SOME snails. There are aquatic snails and terrestrial snails (which I'm sure you're referring to). Aquatic snails generally have gills, while most terrestrial snails have a single lung (I think).

Slugs, like snails, are generally found in moist areas and can often be seen after a rain.

I don't know of a single reference that pulls it all together, but this is a good place to start...

The Living World of Molluscs

  • 1
    $\begingroup$ It sounds like a plausible answer +1 It looks like the same behavior as 'rain worms' (that's how they're called in Dutch anyway :-) - you never see them, but when it rains they emerge in masses from the soil and roam freely. $\endgroup$
    – AliceD
    Nov 2 '15 at 4:52
  • $\begingroup$ @AliceD chat.stackexchange.com/transcript/message/25100934#25100934 $\endgroup$
    – AMR
    Nov 2 '15 at 7:09
  • 1
    $\begingroup$ Please could you add some supporting scientific material that reinforces your answer and allows further reading. $\endgroup$
    – rg255
    Mar 8 '16 at 7:36
  • 1
    $\begingroup$ @alice to be fair the worms emerge becasue they start suffocating in the saturated soil. $\endgroup$
    – John
    Apr 11 '18 at 4:09
  • $\begingroup$ @John - mmm and what about toads and frogs then? They also show this terrestrial dwelling when it's wet $\endgroup$
    – AliceD
    Apr 11 '18 at 6:47

In most species, slugs and snails survive droughts (which would otherwise kill them by dehydration) by creating "slime tombs" (initially-viscous bubbles of slime) around themselves. these tombs or pellets will quickly dry out, on the surface, while resisting total dehydration. When it rains, these capsules will re-hydrate or "melt," beginning on the surface, and the creatures will crawl free. Because they've gone without food, they're ravenous, and go everywhere, "rasping" softened nutrients from the surfaces of plants and even objects where "blossoming" single-cell organisms (also recently re-hydrated) can be found.

  • 2
    $\begingroup$ Welcome to Biology.SE! Can you please add references? (I am not trying to be rude) I like your answer, but references would certainly complete it. $\endgroup$
    – TanMath
    Nov 2 '15 at 23:35

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.