They know the word 'no' (although they often ignore it) but so do all the other animals, so if you dive in crying 'NO!' then everyone present freezes or flees. As the Bungles are the most confident and bumptious animals in the house, they tend to assume that the 'no' is for someone else, whereas roughly 80% of the time, it's an attempt to stop Bungles doing what Bungles do best: mischief!
I need a nice short word that is distinctive and doesn't sound like no. I was thinking maybe 'Bast'.