What should I do about my unexpectedly lonely pet male mouse?

Question

My husband and I had two mice, brothers who occassionally faught but overall did well together, living in the same cage. Unexpectedly Clive died a little over a week ago, so Grady is now left alone. We can't introduce a new species or a new mouse for fear of him killing either, what should we do to keep him from becoming depressed or lonely?

Answer 1

If you handle him enough, he may be fine. He may be fine even without that, especially if he's older.
If he seems sad after a week or two, it might be good to introduce a new mouse. Wash the cage thoroughly first, rinse with vinegar and then water. Wash both mice with mild soap or detergent. Put something new (maybe a box or french roll or a little branch or some toilet paper tubes) into the cage to change the look and feel of it. Then put the 2 mice in together and observe them carefully. If there is no serious fighting they will be okay. If they don't get along, keep their cages next to each other and try again in a couple of weeks. Meanwhile put some of each mouse's soiled bedding in the other mouse's cage. You should be able to get them together in time. Mice are pretty social.