baby deer mouse

Question
My cat brought home a tiny rodent, which I have determined from photos on
the internet to be a juvenile deer mouse. It had fur and its eyes were open.
The first day, it really looked like a baby, with a big head and tiny body, barely
the size of my thumb joint, maybe an inch or so long, and she/he snuggled in
our hands for warmth. I gave her sunflower seeds, oatmeal and sesame seeds,
heat and an old sock. Now four days later, it's very perky, eats a lot of the
seeds etc, and seems to be defacating, peeing just fine. It has two small teeth
top and bottom, and tries to ward us off with small bites. She has also grown
and filled out, to maybe a whole thumb length now.
I would like to release her back to the wild, but I want her to have a fighting
chance, especially as it is September and the weather is getting wetter here in
the Vancouver, B.C., area. I suspect this mouse is about 3-4 weeks old.
When should I release her? I was thinking of letting her out near a wooded,
park area, with a box and some food supply.
Please let us know. I have four cats, and one of them is bound to become
suspicious of my special package on the shelf!

Christina

Answer
Hi Christina,

The best you can really do is look at forecasts and pick a time when you're likely to have decent weather for a few days.  I'm not familiar with weather patterns in your area, so I can't really say, but with four cats it might indeed be a good idea to release her soon!  Plus, the quicker your release her the more likely she will be to adjust to the outdoors.  She will almost certainly have enough instincts to help her handle finding cover in rain (assuming you release her when it isn't storming).  Try to pick a spot that isn't very open or exposed and perhaps scatter a little of the food in case another animal finds it.

Beyond that, I think it's just a matter of crossing your fingers!  She should be fine - wild mice have very strong instincts for survival.  :)

Best of luck!
-Tam