I didn't believe it until I actually heard it. There is an unusual mouse who literally howls at the Moon before killing its prey. Called the grasshopper mouse, it's a rare carnivorous mouse who eats bugs, scorpions, and even other mice. Apparently they also let out this piercing cry before moving for the slaughter.
Over at Laelaps, Brian Switek has a great article on these strange little mammals, whose evolutionary pathway is still contested.
Before crunching into its prey, the grasshopper mouse howls. The sound is a high, sustained whistle which pierces the desert night. It is as if the rodent is imitating a wolf at miniature scale – the grasshopper mouse even stands on its hind legs and throws its head back during the shrill call. And while the rodent may cry spontaneously or emit the sound as a warning when it spots another of its kind, the grasshopper mouse regularly howls just before a kill.
Even weirder is how the mouse has repurposed its decidedly non-predator-style teeth for the purposes of crunching on flesh and slurping blood. Find out more by reading Switek's post at Laelaps.