Should I Keep Deer Mouse?

Question
I have adopted deer mice in the past. They were babies that I rescued from my cats one winter and ended up keeping because I was afraid after months of raising them from babies in captivity, that they would not be suited for the wild, and because I fell in love with them. They've since had pups, and been separated in two large cages by sex. I have had them for almost two years. They seem relatively happy, active, and get plenty of food and exercise. Some of them will even eat out of my hand. This last winter, several adult deer mice got in the house. I captured 11 mice in a no kill trap and kept them in two small cages to be released in the warm months. I have already released one cage, and have six more mice left to release. I was hesitating because I was tempted to keep one of them who has an eye problem that I was afraid would interfere with it's ability to survive. I described the eye problem to a vet, and he felt that since it hasn't worsened in months, and that the mouse acts completely normal otherwise that it is probably a scar, and that the mouse will be okay otherwise.
Now that you have the history, here is my dilemma. I am torn about keeping the mouse or releasing him. Part of me has become attached to this mouse because he stands out from the rest, is braver than most of the others, fun to watch on the wheel, and because I feel sorry for him with a scarred eye.  I do worry about keeping him with my other mice without having his feces tested for common diseases, or if they will get along. I also worry that he won't be happy living in a cage after being free for most of his life, or that he and the mice he was with, will miss each other if I separate them, and that it will be too traumatic. I worry about his survival in the wild. I could keep him and one of his buddies perhaps as a companion. Am I being selfish? Should I just let go? Would the mice be so much happier in the wild? What expertise, or experience do you have with this subject? Thanks in advance!

Answer
Hi,

This is a hotly debated topic in some mouse circles. Some people feel that any wild animal should stay in the wild no matter what. Others feel any animal can be a pet. There isn't one correct answer to the question, but some tacks seem more sensible than others. Let me simply explain to you exactly how I think about it.

For me, the mouse's health and happiness are the number one priority. And I would put happiness ahead of health.  

A hand-raised baby mouse is probably going to be pretty happy as a pet. It would also have less survival ability than its wild cousins and so its health and happiness are connected. I generally recommend keeping these little orphans and they make great pets, as you well know.

An adult wild mouse, on the other hand, may well be unhappy as a pet, even though it is healthier, has more food, is safe from predators, etc.

For me the test is this:  Does the mouse spend a lot of time trying to get out of the cage?  Does it like to be handled, or is it deathly afraid of people?  These questions are the most important indicator of whether it wants to be a pet or not. I would always recommend keeping a mouse who likes to be held. I would never recommend keeping one which spends a lot of time trying to escape.  The areas in between are grey.

It's hard for me to know exactly what is wrong with your favorite captive; a 'scar' won't be any hindrance to its survival capacity.  If the vet said it's OK it probably is. Also, if it is a boy, it won't be able to live with your others and may be lonely. This can be helped dramatically by keeping the cages side by side. But it's still pretty tough to be a single mouse.

I had a situation recently when I had half-wild babies of my tame mouse and a naughty interloper. First generation hybrids are notoriously wild.  I got to the point where I had two babies left (gave the rest away).  One got tame.  The other just got more and more frustrated with being in the cage and was starting to bite when held. In the end, even though she would have fewer skills than a wild mouse, I realized she was simply unhappy in captivity. I was torn in two. Although I knew her life would be far shorter in the wild, I let her go one beautiful, warm day. I think it was the right decision.

What it boils down to is simply trying to get into the mouse's head and heart. I hope my thoughts have helped you somewhat.  Good luck with your decision.  

squeaks n giggles,

Natasha