Mouse population explosion!

Question
Hi there... So, bought two breeder mice for my son as pets. Wanted to save their lives from being fed to snakes and thought it was the perfect idea. I have had them for a little over a month and tada, found SEVEN babies just born this morning in their cage. Slightly freaking out here. Now, I have nine mice in a 45 gal aquarium. I know that I need to get the male out, but not too sure how soon I need to remove him before he tries mating again. Also, I know that I shouldn't move the babies or mama for a good few weeks. How soon before I can tell the sex of the babies and will they mate eachother too? Can I put all the males in one aquarium and the females in one?

Any tips would be great. My husband wants to take the male and get rid of him today. Not too sure what he means, but he said "let him go" in the wild?! I am an intense animal lover and feel responsible for all of these little guys now! HELP!!  

Answer
Dear Vicki,

This site does a great job showing the difference between the mouse sexes.  You can start handling and identifying them at one week:

http://www.thefunmouse.com/info/sexing.cfm

Unfortunately, mice usually mate within a few hours after giving birth.  This is how they have litter after litter, every three weeks!  So I think you are in more trouble than you know.  You will probably find a second litter three weeks to the day after the first litter was born!

You can keep all the girls together in the big tank.  Separate them at 4 weeks, because they can mate at 4 1/2.  

As for keeping the boys in one tank, the bad news is that boy mice don't always get along.  Eventually there will probably be fighting.  Often a male mouse has to have his own cage for this reason.  It's ok for there to be a lot of squeaking in a mouse cage, but blood means it's time to separate them.  The cages should be as close as possible so they can continue to communicate with each other, as it's rather lonely being a bachelor mouse.

If you need to get rid of some of the mice (the males),   first I have to offer you a horrible idea:  If you can sex them within a few days, you can 'edit' the litter by killing the boys.  This is most easily done by (sorry!) throwing them down hard in the bathtub.  It kills them immediately.  It's also something I could never bring myself to do, and probably you neither.  But I want to give you all options.  This is what breeders do, because there is no room in the world for hundreds of single males in their own cages.

Otherwise, you are going to have a bunch (if you are lucky, not so many) of boys who eventually may not want to live together. Letting them (or their father) go in the wild would be crueller than killing them.  It's terrifying. Everything would scare them  and they would die of something unpleasant because they don't know how to take care of themselves.  I agree with you over your husband here.

The first thing to do in this case is find out if the pet store will take them.  This means of course that they might become feeder mice.

The next idea is to find homes for them.  For instance, you can go to the local schools and try to find science teachers or general classroom teachers, and suggest a mouse or two as a pet.  Some teachers may even want to take a pair so the kids can watch babies grow up.  You can also put up notices in the library, town hall, or anywhere that notices get put up.  You may have a local want ad paper too.  Make the notice or ad sound exciting-- write how great it is to have a mouse as a pet.  Here is a paragraph I wrote for a girl who wanted to convince her mom to let her get a mouse:

"As for convincing your mom.. Mice are the smartest small pet you can get.  They cost very little to maintain.  They are quite clean if you keep their cage clean (but they do poop and pee on you, so don't wear your best outfit holding them!).  They are very friendly, curious, tenacious, and creative, besides unbelievably cute.  They are very loving.  They don't tend to bite, like hamsters do; they are easier to hold than gerbils.  They stay in their cage so no one has to deal with them except you.  You will be learning how to care for a pet, and by extension, how to be responsible for something other than yourself; that is a very important life skill.  They only live 18-30 months, which means frequent tragedies (well, learning to deal with mortality is a skill too..) but they are not a long-term commitment.  You can leave them in their cage for up to three days (no more) as long as they have lots of food and water, including wet vegetables or fruit (carrots, apple) in case their water bottle clogs-- so you can still sleep over someone's house and Mom doesn't have to tend to the pet.  They are easy to transport to go on vacation with you or stay at someone else's house while you are gone; no in-house petsitter needed (she can't say that for the plants, now, can she?)"

You might be able to use some of that.  

Also, there are rat and mouse sites which may have information about adopting out extra mice.  Even though some sites or organizations mention only rats, many rat people will help with mice:

American Fancy  Rat and Mouse Association:
http://www.afrma.org/

Rat and Mouse Club of America (they have info about rescues, though unfortunately CanadaRatFinder seems to be obsolete):
http://www.rmca.org/

North American Rat and Mouse Club, Int'l:
http://narmci.8k.com/index.html

The Ratster-A Rat and Mouse Directory
http://www.ratster.com/

Follow all the links you can; it can get a little frustrating, but there are for instance also lists of veterinarians, whom you could call and ask.

I hope this helps.  I really understand the problem and have great sympathy for your plight.  Do remember to completely enjoy all of the mice during this awkward time!

squeaks n giggles,

Natasha