I live in a rural area in a somewhat unfinished house that hasn't been maintained as well as it might have been. Consequently, we have mice in the walls. They're actually quite lovely little creatures: deer mice (Peromyscus maniculatus). They're also native to Nova Scotia, so I feel a bit bad setting traps for them, even when they get cheeky enough to watch me from the top of a bookcase.
Every now and then my cat, who never goes outside, will catch one. Usually somewhere in the still-dark hours of the early morning. Then she lets them go in the bedroom, which has a sill on the door, so they run around and around the room while she chases them. Eventually she gets bored and they escape, or they go into shock so I have to scoop them up in the morning and release them into the woods. Every now and then she actually kills one.
(I know, I am a monster for not intervening. But at three a.m. I am pretty much a zombie and capable only of groaning and burying my head under the pillow.)
Once, I discovered the tiny body in the morning and instead of a mouse, it was a shrew (probably a masked shrew, Sorex cinereus). I still don't know how it ended up inside, because as far as I can tell, shrews are not usually house-dwellers. I can only guess that perhaps it got lost in the tunnels under the snow (there was a lot of snow on the ground at the time) and followed a mouse hole, or the dryer vent, into the house. Only to be captured by a housecat.
Shrews, if you're not up on your mammalian classification, are not rodents (which, of course, mice are). Though they do resemble mice somewhat, they're actually more closely related to moles. Masked shrews are very, very tiny. Even smaller than deer mice. Sadly, this dead little beast is the only shrew I've actually seen (though I did spy a living vole -- a mouse-like rodent -- a couple of times in one of our rock walls).
Image © Niko Silvester. Please do not use without permission. Thanks!