re-introducing female mice

Question
QUESTION: I have four mice and was given a very large tank and so decided to get another mouse, anyway to cut a long story short we ended up with 3 babies.  I followed instructions and put vanilla essence on the bums and but them altogether in a completely clean tank.   Anyway 2 of the babies were fine but what looks to be the runt was picked on.  Blood was drawn and so I separated the old from the new.   I have slowly been releasing the old mice into the new mice's tank but I am left with the one that drew blood on the runt.  My question is, will they get on this time?  I feel so sorry for the little one I don't want to distress her anymore but I also don't want to have to clean two cages out.  What do you think?

ANSWER: Dear Nicky,

You can try to put them together again. It's best if you wait a little while until the runt is a little bigger (I don't know how long it's already been of course). During that time don't forget to give the solitary mouse lots of extra love because she lives alone, and keep the cages close so they can communicate.

This time you won't use any vanilla.  The reason to use the vanilla is so that none of the mice has a 'home court advantage.'  In this case now, however, you want the aggressive mouse to feel like she is the newcomer and thus should not be territorial and want to attack the others.  Wait until the cage is nice and dirty!  It should strongly smell (to the mice) of the resident mice (If it's a large tank wait two weeks after cleaning).  Again, chasing and squeaking is fine but blood isn't.

It's possible that it simply won't work.  Some mice are simply aggressive to other mice.  These mice are perfectly lovely mice and make lovely pets but they are just following unfortunate mouse instincts.  In the event of a continued two-cage solution, nobody should live alone. Mice are very sociable creatures and can get depressed and sick when alone.

Let me know what happens.  I hope it works out well.  And thank you for doing research before writing. That makes my "job" easier.

squeaks n giggles,

Natasha





---------- FOLLOW-UP ----------

QUESTION: Hi Natasha

The mouse I was left with been was put into the very smelly tank yesterday and at first she and all the other mice were very excited, they calmed down and all went to bed in the box provided.  It has a plastic lid so I can see what is going on.  On the night they all woke as they do, and then all hell broke out the aggressive mouse was chasing the young ones again, not the runt this time, one of the others and then there was blood!  So out she came, Im not sure she will ever get on with the new mice....   So I now have six very happy mice old and new living together and one aggressive mouse living on her own again.   I may give it one last go, but it would seem I am destined to be cleaning two cages!

Answer
Hi Nicky,

Thanks very much for letting me know what happened.  If the aggressive mouse simply can't get along with any of the other mice, you are going to have a 'single' mouse, who will need lots of extra love and attention from you.  Is there perhaps one she doesn't fight with, that she could live with? All you can do is try.

Best of luck.

squeaks n giggles,

Natasha