When you're on the beach and have to take a piss but don't want to go into the water. Instead you lay down, dig a hole near the groin area, and pee in it, much like a turtle does when it lays its eggs.
I was so hungover on the beach I didn't even wanna move, so I just laid a turtle egg instead.
When you are almost to a restroom door/stall and someone cuts in front of you and takes the last spot forcing you to seek out a new place to go.
I was en route to take a huge crap when some turtle hopper jumped in front of me. The turtle was peaking out but I managed to contain him long enough to find another place to go.
When you have to take a shit so bad that you can feel it crowning, but the shit has not yet breached the anus barier...the stage just before Prarie Dogging.