The article title is a little misleading - the tadpoles of this frog don't poop because they're only in a small amount of water and they'd quickly foul it if they pooped frequently like other animals. Instead, they wait until they start to become frogs, then they safely poop outside of their spawning pools.
In the video game Black & White if you punished your creature every time it went to the bathroom it would eventually stop doing it completely. Until they patched it, anyway.