Well, there's a line in the sea song "Leave Her Johnny":

"Oh the rats have left and we the crew
   Leave her, Johnny, leave her
It's time that we were going too
   And it's time for us to leave her."

Or wait, would mice do in a pinch? There's a really cool line in June Tabor's version of "Dives and Lazarus" that goes "Hell is deep, hell is dark, hell is full of mice."