introducing male mouse to baby

Question
Hi natasha,
Today i found a wild deermouse ( thats what i believe it is ). A year ago i found 4 and only 1 surived. its a male and named rue. He always seems lonely and ive heard stories of a male mouse taking after a baby. do you think it would be okay to try and introduce them? Rue me adult male deermouse is really sweet and has always been interested in my other mice. Please reply asap. thanks!!

Answer
Dear Hanna,

There are two issues here.  One is that a wild mouse (the new one) will  probably never be happy in captivity.  I only recommend that people keep a mouse if they raised it by nursing it by hand (not sure how old yours is?). Even in that case, the test is whether it seems happy to be in the cage or if it spends a lot of time either just hiding or just trying to get out of the cage.  The other issue is that males almost always fight, and a wild mouse is likely more aggressive than a tame one.  Thus the chance of Rue accepting a friend without eventually fighting with it are slim.  However, there's no real harm in trying, as long as you are closely monitoring the situation to make sure Rue isn't hurting (blood) or terrorizing the little mouse; and to see if the new mouse really wants to be a pet.  It may be a while before the baby gets big enough for Rue to see it as an adversary.  

squeaks n giggles,

Natasha