To rescue a mouse or not/ bullies

Question
Dear Natasha,

Recently my brother got two mice from a local pet store and they are both males which what I have researched could lead to disaster and I fear it already has which I will explain here soon after a bit.

I was told over the phone that they had to separate the two because one was getting picked on a little by what I am assuming at the time was a dominant male mouse. He was biting his tail or some from what I was being told and it was only today that I was able to go have an actual look at the two boys after work. Needless to say it was much worse then they had described.

I got a good look at the poor picked on boy's tail and there is obvious signs of blood having been drawn plus the tip was plain missing! They told me they are going to keep them separated for a few days then try having them house together again at the advice they received from an 'expert'... now I say this with a bit of sarcasm because their mouse expert was nothing more then a clerk at the store they had purchased the two from. We all know that their only job is honestly only to sell but sometimes you run into one who seems to know more and is quite insightful.

Now after witnessing what I consider to be a mouse bully I am tempted to rescue the other little male from my ignorant mother and eleven year old brother because despite my protests they refuse to listen to me about how housing them together will eventually lead to the death of the picked on one or possibly even the aggressor.

Should I follow what my heart says and rescue the little one from the people who refuse to listen and call me a know it all or should I let them learn a lesson? I honestly don't want one to die but I know if I just take it I will get yelled at so should I attempt to buy him off of them? I own several mice already and wont mind an additional one since all I have to do is dig out an old cage to house him in away from my females.

If I manage to capture an image of the boy's tail I will upload it.

Answer
Dear Eloin,

Male mice fight to the death. Keeping mice together who are going to fight is like dog fighting. It is simply inhumane. Please don't let mice suffer to teach someone a lesson. It is the mouse that learns the lesson.

Please let your mom read this. I am an expert. I have 37 years experience with mice and have answered almost 2000 questions on this site. Pet store attendants generally know nothing about mice. As far as I can tell, they hire them not for expertise but for who can best pretend they have expertise. In some species, like rats, males can and should live together. In others, like hamsters, most individuals of either sex prefer to live alone. With  mice, girls must live together, and boys must live alone. A pet store attendant may think you can generalize from one species to the next.

The only situation where two male mice might not fight is either a father-son pair, or litter mates, who have never been separated. Because this does-- though not always-- happen, people may see two males together and think it will work for other males. Or they see very young males who don't fight yet. But most adult male mice will fight.

Please put down your swords and do what is right for the mice. It is understandable that your mom believes the pet store attendant. Store personnel are supposed to know what they are talking about. But they don't always.

As for the tail, watch it for infection. It will probably just heal, and he will never notice it is gone. But if there is any redness or swelling of the area, or the mouse squeaks when touched, he should go to the vet.

My best to the mice.

squeaks,

Natasha