This is true, but to my understanding you can also bring them to the surface by rubbing a stick against the ground to create the right rhythms—they’ll think a flood is coming and come to the surface without any water at all!
If I remember right, it’s called “worm-fiddling” or something like that?
TIL
I was going to leave it at that, but the forum won’t let me post just that, so I’m tacking on this entirely unnecessary sentence.
For finding the entrance, I have the perfect puzzle, but it’s in an unpublished game, so I don’t want to reveal that yet.
I used a rope/hook/grappling hook/manhole/sewer puzzle in ‘The King’s Ball’. You could take a look at that for ideas.
What about filling a bucket/sprinkler with water and sprinkling water on the worm patch to simulate rain?
Sounds like the Xanth novels where everything is a play on words. There’s even an old DOS game called Companions of Xanth. Yes, you can get butter from buttercups. A censorship is a boat with sensors on it. And I shouldn’t have to explain what eye scream is. 
I’ve read that the drowning part is actually a myth as earthworms are capable of living underwater for extended periods of time. The real reason they come up is unknown, but some scientists think they do it to be able to migrate to new places.
But yeah, in real life some noise would not be enough to bring them up. Maybe I’ll make the actual solution sprinkling the the soil with water and make the drumming gag an optional scene you can discover while waiting for the worms to come up.
If you’re concerned by authenticity, this is the method I remember the old-timers using when I was a kid. I also saw a variation using a dolly and couple of car batteries.
ETA: I’m not saying this was super humane, just something fairly common. Given the worms were later impaled, drowned, and then fed alive to hungry fish, concerns about being humane to the worms weren’t first and foremost in many minds.
I would have thought that ‘humane’ only applies to humans, so this would be ‘wormane’.
This thread’s train of thought was wildly interesting to me, because like a lot of y’all, I assumed it was so they didn’t drown. Turns out it’s mostly not that probably, but kind of a little of that? Here is the Scientific American article and one from PennState Extension I found useful.
Bizarrely, this is a pretty contested question. It appears that the outdated assumption was because they would drown, but more recent consensus say that isn’t largely true, because they can survive for ~2 weeks submerged in water, and we know they do require it to be able to like, exist and not fry to death on the sidewalk. However, even more weirdly, apparently under very specific conditions they can “drown.”
It’s not really drowning, it’s suffocation, because sometimes waterlogged soils don’t have enough oxygen inside of the water that floods all of the subspaces with air pockets inside of the soil for them to be able to live. So they do die from the water, but not because of the water replacing air necessarily, it’s because the water itself isn’t oxygenated enough for them to tolerate it replacing air. But if it were they’d be getting along just swimmingly. (They breathe oxygen through their skin, and have to be wet for it to dissolve properly. That’s why they have gooey mucus.)
I’ll go out on a limb and say it’s likely that if the water is warmed, (as is common from urban runoff, due to accruing heat from dark, impermeable, hot surfaces like asphalt or sidewalks, allowing for maximal contact time between the surface and water) then this might play a role, as warmer water dissolves less oxygen (as fellow tropical aquaria enthusiasts know!) Any pollutants ferried in the water that the squirmy wormies are slurping up through their skin might also be a factor, but it’d depend, and I’d imagine urban earthworms are fairly tolerant of all the nasties in our ecosystem.
Apparently there are a couple of ideas as to why they do this- the drumming of rain on soil sounds similar to moles, which predate them, but a few species display mating behaviour in response to rainfall so they squirm their way up to the top to meet up with other worms, and more generally it could just be that they’re taking advantage of their increased range of travel (before they would dry out) to migrate somewhere new.
Also if you’ve read this far in the worm-y tirade, I’m going to remind you that the USA and Canada are experiencing invasive hammerhead worms that are decimating local populations of earthworms, slugs, and snails. They’re apparently doing amazing with climate change, which sucks for us. Like the Spotted Lanternfly, the current recommendation is to kill them on sight. They recommend not cutting or squishing, and to instead pop them into a jar of rubbing alcohol.
Haha, I was thinking about writing an essay about this too, but you got there first. Apparently earthworms are more interesting than most people give them credit for
Do you guys think that a text adventure where the player could choose to solve puzzles in a more bizarre way could work? Perhaps there could be achievements for each time the player finds one of these alternative solutions.
I think puzzles with multiple solutions should be the norm.
Achievement Unlocked: Worm Whisperer
You’re a kindred spirit with the dirt dwelling denizens.
The worms do react at the drumming because they have very few senses. Drumming = rain (in their primitive brain). Have you ever watched a blackbird on a lawn? It knocks on the ground with its beak.
As this thread has been hijacked by worms, it might be worth mentioning a worm-focussed game.
The Adventures of Worm by Neil Davidson (ZX Spectrum 1981). You play the part of a wriggly worm who must leave his comfortable worm hole and make his way through all sorts of worm-threatening hazards to get to his uncle’s Wormsday party.
There are other games with ‘worm’ in the name, but these aren’t about worms. Any others?
I would so play an IF game with this conceit.
