troublesome

Staff at the safari park were baffled by the mystery of the disappearing whirlpool bath.
Every morning they filled the open-air bath outside one of the guest lodges, and every night it was empty - even though no leak could be found.
It was only when a guest heard a mighty slurping and went outside with a camera that the culprit was discovered in the shape of Troublesome the elephant.

source. via.