Phil's Rambling Rants
Curious. When I've had a multispecies infestation, The Mice Cube will preferentially catch me a shrew before it catches me a Peromyscus (deer mouse). I put the peanut butter, smeared on a small piece of cracker, deep into the Cube, and smear a whiff of peanut butter on the outside of the door to lure them in.
Shrew metabolism is so notoriously high, that if they don't eat every several hours, they die. Where the Peromyscus can afford normal (for a wild rodent) neophobia and avoid a freshly-set trap, a shrew is much more desperate.
There have been times when I've seen the shrew trundle by the trap, yet it could be days before it'll finally attempt to eat the PB. I'm thinking that since they are carnivorous, they don't really understand what peanut butter is, and the smell isn't enticing enough until they become desperate. It isn't like I have food out anyway; I know when its harvest time that I have to be more vigilant on making sure dishes are washed and foods are put away promptly.