A Little Bit More
The House Mouse is well named; wherever humans live, you’ll probably find House Mice as well. Although they’re occasionally found in fields and woods as “wild” populations, they’re almost always found in close association with humans, especially where food is stored.
The word “mouse” comes from an ancient Sanskrit word meaning thief. The House Mouse is believed to have been brought to North America by the French, English, and Spanish explorers as early as the 1500’s, and their spread has mirrored that of human settlements.
A House Mouse avoids enemies by remaining hidden as much as possible and seldom wanders far from its own territory. They dislike being exposed and quickly scamper across open spaces, scurrying from one shelter to another. The House Mouse’s two most important senses are smell and hearing. Despite rather large eyes, its eyesight is not good, and it relies heavily on its whiskers and a knowledge of its territory to help it navigate. Although human traps and poisons are probably their major “enemies”, these rodents are preyed upon by almost any meat-eating animal you can think of. Mice compensate for the constant inroads on their population by being incredibly prolific. Females can begin breeding when only 6 weeks old, and produce a litter of up to 11 young about every 4 to 6 weeks thereafter! Fortunately, most mice don’t live more than a few months or we’d be up to our eyeballs in mice!
Activities
Mice, Mice, and more Mice
Objectives: Improve math skills
Materials: Pencil and paper
If a female mouse is mature at 6 weeks and has 10 young every 6 weeks after that, how many young will she produce within one year? Have your students work this out on their own if possible, or with help if they need it.
1. How many 6 week periods are there in one year? (52 divided by 6 = 8.6)
2. It takes 6 weeks to mature so subtract one 6-week period from the total. (8.6-1 = 7.6)
3. She has 10 babies each time she gives birth (7.6 X 10 = 760 babies!)
If you wish, you can get more complicated if you begin to count the young of the first mother. To make it a bit easier, you can assume that of the 10 babies produced each time, half will be males and half females.
Key Concepts
Adaptations and Diversity, Identification, Life Cycles
Questions
Do you have a question for a naturalist? Go ahead and ask!
It's easy -- just fill out this form, submit your question and you'll receive an answer shortly.
Posted by M Brodhead on August 15, 2006 at 04:47 PM
Q: I recently frightened a mouse out of hiding and as it ran off, it appeared to have several pinkish lobes sticking out of either side between the front and back legs. There was also evidence of a nest in the area the mouse had just vacated. Can mice carry their babies attached to their teats somehow, or was this likely some sort of aberration?
A: My guess is that what you saw were "pinky" mice attached to the female's teats. Not an aberration at all. Pinkies are new born mice and are very small. When the female panicked, here instinct was to run away. Good luck!
Posted by Jeff Hollmann on July 02, 2006 at 09:59 AM
Q: I have caught around 8 mice in the last two weeks and i was wondering if it could be the same mouse. I catch it in a live trap and let it out about 80 feet away from the house. Icatch them in the same trap in the bottom drawer of the stove . The reason i am wondering is that i see only a few droppings around the same area by the stove. I would think if i had that many mice there would be more evidence of them. Thanks for your help.
A: We often have this notion that animals are where they are without any real "understanding" of thier location in space. Wrong! Many animals, especially mammals and birds are especially good at knowing where they are and getting back there if moved elsewhere. So...I think it's very likely that your 8 mice are not 8, but 1 or 2. Would be very interesting to do a little experiment. Why not paint a white spot on your mouse's tail or tie a string around its tail and see what happens? If you do want to release your mice, be sure you take them several miles away, not 80 feet. Good luck.
Posted by vicky ford on June 05, 2006 at 06:15 PM
Q: i placed a small cream egg by the side of my bed and then a few days later i went to go to bed and found all the paper in a pile but the egg gone how could it of carried this there was no mess other than the paper so it could not of ate it there and i cant see how a mouse could carry it! so i placed a kit kat there and now the same has happened to this, i am starting to freak out and am now sleeping on the sofa. have you any idea what it can be if it not a mouse, if not how can i find out, or catch it!! help!!
A: Take a good look at those papers from the candy. If it's a mouse, there should be tiny teeth marks on the paper where it chewed off the wrappers. Mice are quite good at carrying food in their mouthes so unless the candy is quite large, they probably carried it away. Hope this helps so you can sleep on your bed again. Why not get a live trap and catch the little free-loader? Good luck.
Posted by Katie Gooder on April 19, 2006 at 09:10 PM
Q: Hello, We caught a tan mouse in our house this morning, very friendly. He is tan with a white band around the neck, soft hair. We have him in a cage, he looks very domesticated. Do domesticated mice just show up in a persons house? We have had field mice before, but nothing that loks like this. He has a small patch of hair missing on him do we need to be concerned about this? Is it safe to keep him. Any help wil greatly be appreciated. He seems healthy and eats and drinks good.
Thanks
Katie
A: Sounds to me that your mouse is not a House Mouse. House Mice are pretty much uniform gray without the white. Check out the tail too. If it's tail is two-colored (tan and white) it's probably NOT a House Mouse. Granted House Mice can vary quite a bit in color but I think you have something else.
Mice can be especially difficult to identify but I do have some possibilities for you to look up. Try looking up the North American Deermouse, White-footed Deermouse, and Western Harvest Mouse. If you can get a photo of these 3, it may tip you off to your new "boarder". These are the 3 species that seem most likely to be your animal.
Just to be on the safe side, do be careful if you handle the mouse in any way. Sounds like your mouse is doing well but there's always the chance that it will nip so avoid that possibility. Other than that caution, I think you may have a nice little pet. Once you're sure what you have, you can find out if there are any other needs that will help keep your animal healthy. Enjoy.
Posted by Angie Pyper on April 13, 2006 at 04:26 PM
Q: hello. We have mice in the garage that my cat loves to hunt. If I catch him soon enough, I release them outside. Unfortunately, I believe he ate one the other day. We do NOT use poison on the mice, we have live traps. So, would eating this mouse harm my cat in any way? thanks!
Angie
Great site by the way!!!!
A: Your cat is just doing what it's well-adapted to do - catch and eat little animals. No, the mice won't hurt your cat in any way and in fact are probably a very healthy addition to its diet. It's interesting to note that people who care for raptors (birds of prey), make sure these animals get whole animals to eat. As a result, all of the nutrients available in a whole chicken or whole mouse, for example, are available. Commercial foods for cats probably don't have everything (they may have some added vitamins etc) that a whole mouse would have so the live foods a cat finds probably are good. Of course, we don't want our cats catching nesting or baby birds but an occasional mouse shouldn't be a problem. Thanks for asking.
Posted by graeme allen on April 04, 2006 at 08:04 AM
Q: I live in a 3 year old house I have mice in my integral garage and are now in the loft .I am trapping some in the garage and in the loft but they keep appearing.I am trying to eliminateall sources of food from the grage i.e. wild bird food.Once they are in the garage can they climb up from behind the walls or could there be a nest in the loft as well?How often do they breed? Any help appreciated.
Graeme.
A: Mice are very good climbers and can easily scale up inside walls if there are places where they can get a good foothold. Eliminating any food sources is good but they're often after a good place to make their nests - especially in the fall. You haven't told me where you live but in areas that get fairly cold weather, they often move into human buildings for shelter as the season cools down. Keep in mind that there are lots of different kinds of mice. The House Mouse, found all over the world, is most likely to stay in and about human buildings. But native mice will use buildings too so it's hard to know what kind you have. Mice reproduce at an incredible rate so within a few months can have several litters. Trapping is probably your best bet but you'll have to release them quite far (a mile or more) from your home to ensure they don't return. Best of luck.
Posted by Susan Muncie on March 30, 2006 at 08:05 PM
Q: We caught a mouse in our furnace room in a live trap (one that holds lots of mice). We took it through our backyard over a wide creek, all total about 600 feet away from the house. It has been 7 days and every morning there is one mouse in this trap. I plan on marking it tomorrow with a dab of color, but
is it possible this is the same mouse. I can't imagine there are that many mice in our walls since we haven't heard or seen them. We have a walkout basement and the furnace room is in the back of basement next to a sliding door.
A: Animals are often very good at finding their way back to an area once they're removed. I don't know how much work has been done with mice, but I could easily believe that your mouse "could" get back to your basement if there was only 600 feet or so distance involved. However, I find it a bit difficult to believe that it not only gets back to your house but also gets into the trap each day too! I'm guessing that you have more than one mouse although there may have been a few repeaters. I like your idea of marking your next mouse so you'll know. I'd love to have you let me know the results too. Thanks for asking.
Posted by Sharon Scheib on January 18, 2006 at 06:05 PM
Q: Hello!
We live in rural upstate NY. One of our cats was chasing a mouse last night in the house. We think it was living "between the walls" and popped out somewhere. We wonder if it can survive the cold if we put it in our unheated shed- if it is used to living somewhat indoors. It seems fine - ate sunflower seeds,piece of apple and water and is curled up with some cotton and paper in a big covered bucket in our basement. It seems like a white footed mouse- is that the same as a "house" mouse. So we wonder should we keep it inside and "care for it" til it warms up a little in March (2 months)?If we release it in the house will it find its way back to where it's been living or just scramble and end up hiding within our living quarters? Or would it do best if we provide nesting material and shelter in the enclosed shed? Thanks for any help-Sharon
A: You sound as though you've worked with wild animals before - your concerns are quite reasonable! You are correct in being concerned about putting your mouse outside after it has been living within your home. Since it is not acclimated to the outside cold, before it could find adequate shelter, it would probably get too cold and die of exposure. I like your idea of providing a place like a cage for your mouse to live in until warmer weather - that works for me! When you do release it, just make sure it is during a warm-spell rather than a cold one, but you already know that. If you do release your mouse in the house, it will probably find its original shelter or if not, find a new one. Only problem there is that it will need food and will probably get in to areas you don't want chewed or soiled. I'm not encouraging people to keep wild animals but in your case I think it makes sense to keep your mouse in the house for now. Best to you and your mouse. Thanks for asking.
Posted by Laura Turnbull on October 14, 2005 at 11:06 PM
Q: Since my cat died a year ago I have had 4 'mouse invasions'. I live in an older home with a useable crawlspace that opens to the family room on the ground floor. Until the most recent invasion (now in progress) the mice seemed to be limited to ground floor rooms, garage and crawlspace. In the past few days we have found 1 dead adult (in a crawlspace trap), one very small mouse upstairs in the bathtub (almost dead) and another small dead one in a sticky trap (the trap was intended for spiders). My son advocates poison but I'm afraid the dead mice will stink. Also, we have 3 dogs and the last thing I want is a sick dog from eating poison or poisoned mouse. I've been doing research on the problem on the internet and have a yard mowing and cleaning day set for tomorrow to eliminate habitat close to the house. After that we will be doing major sanitation and cleaning inside. The question still remains - how do I rid my house of these rodents. They really gross me out!
Thanks for any advice.
Laura in Kansas City
A: You aren't alone - many people have mouse invasions in the fall. There are poisons that are "rodent specific" and won't hurt your pets but I much prefer avoiding the poison route. I'd suggest using live traps (these involve a bit more work) or snap traps. Snap traps are quite humane since they kill the mouse quickly and can be quite effective. Cleaning up the area around your home may cut down on the number of potential mice however mice do move around and if there are places for easy access to your house, you'll get more. Try to be sure and seal up any cracks and crevices around the foundation and check out the garage too - they may enter your garage and then the house from there.
Good luck to you. I know no one wants mice in their house but they're much more of a nuisance than danger.
Posted by ginnie guevara on July 10, 2005 at 03:40 PM
Q: Hi,
The other day I found a mouse in my garage. It is very small and seemed disoriented. It had no fear and just looked at me when i came up to it. We put it in a box and my grandchildren asked if they could keep it. I purchased a cage, food and bedding for the mouse. He seems quite content. My question is should I continue to keep the mouse or should I release it. Will it surviuve if I release it. I am also concerned about disease. Thanks, Ginnie Guevara, Salt Lake City, Ut.
A: This is the $64,000 question - should I keep it? Since you found the mouse in your garage, and you've purchased a variety of products to care for it, I'd be inclined to keep you mouse. If your mouse is a House Mouse, you'll keep it from being a nuisance to you at your house and have the enjoyment of watching it grow and develop. If you can get a field guide to mammals you may find it interesting to look up exactly what kind of mouse you have - there are many kinds. Your grandchildren can help you with this too and they should enjoy the challenge of finding out exactly what kind of mouse they have.
I'd say there is a good chance your mouse will survive. It sounds as though it is old enough to be weaned and should be able to live on a variety of foods available from a pet store. By finding out exactly what kind of mouse species you have, you'll also have a better idea what foods are best for it. If it is a House Mouse, then you'll find that it can eat a wide range of different foods. If you do decide to release your mouse, it will probably survive just fine however.
As to disease, you don't need to worry. It's extremely unlikely that any of you would contract any diseases from the mouse. Always a good idea to wash hands after handling the mouse or its cage materials but that's more for cleanliness, not disease prevention.
Good luck to you and I hope you and your grandchildren are able to enjoy your new "boarder". Having a pet like this will be a great learning experience for you and the kids. Thanks for your question.
Posted by jo on June 20, 2005 at 12:58 AM
Q: There is a mouse in our house. It is brown with a tan underbelly. I believe it is female. My question is: How can we tell if it has any babies? Also, if we hear it squeaking, does this necessarily mean there are others?
A: To know if the mouse has babies is difficult to determine (without seeing them) but if you have mice around, you'll have babies soon enough. I don't think the squeaking necessarily means there are others, but again, if you have one mouse, others are likely to be there too or soon will be. Your mouse has gained access to your house somewhere so if you can do so, I'd try to find an entrance point and be sure to block that. Older homes, however, are almost impossible to mouse-proof since they have too many cracks and crevices that offer access. I hate to do it but I use rodent-specific poison (it doesn't harm pets etc.) to prevent being overrun by mice at my house. Good luck and thanks for your question.
Posted by michaela day on June 13, 2005 at 07:52 PM
Q: I have caught four field mice they were living in my dads grill. I now have them in a box. I would like to keep them as their mother has run off. I need to know what should I feed them. Their eyes are open and they seem very healthy.
thank you
A: The age of your mice is going to be really important here. If they are old enough to begin solid foods, you may be able to provide enough food to keep them healthy and growing. Their mother's milk is really important for them at first but as they age they will begin to find other foods to eat. I think the best thing you can do is call or go to your local pet store and explain that you have these mice. A pet store probably deals with pet mice and their babies all of the time and will have some really good ideas for you regarding care and foods. Keep in mind too that the babies will probably begin chewing on things so don't keep them in a cardboard box long or you'll find a hole and no mice. Good luck to you on this rescue mission.
Posted by suzanne on June 11, 2005 at 08:18 AM
Q: Hi.
Could you tell me please if mice, (paticularly the house mouse) have cheek pouches. I was wondering how they transport food from one place to another.
Thanks!
A: Mice do not have cheek pouches although some other rodents do. Take a look at the unit called "Chubby Cheeks" at www.enaturalist.org and you'll see that the chipmunk does have cheek pouches. Actually, House Mice are not very active storers of food so are not very intent on carrying quantities of food any distance. Any that they may move, would be moved simply by carrying in their mouthes.
Posted by Anonymous on May 29, 2005 at 02:31 PM
Q: Hi!
About 8 months ago, my daughter picked up 2 mice the cats were playing with in the house. They were obviously quite young. We put them in a cage. Eventually, they began to run on the wheel, come out of their house when we talked to them, and let me catch them to clean their cage. Then yesterday, I discovered 2 babies. They must be pretty new. They're still blind, but have a soft fuzz on them.
Have you ever heard of anyone keeping field mice? My daughter just didn't want the cats to kill them. We've had domestic mice as pets before so I still had a cage. They actually seem quite content. I can put my hand in the cage and they don't run away. Sometimes they even let me stroke their fur.
Any suggestions about the babies?
One more weird thing - we've had mice in the house over the years. About 2 weeks ago, I went to feed them and there was a 3rd mouse in the cage. It was smaller than the 2 I already had, a little more high strung, and too big to be a new baby (I had just cleaned the cage the week before). This mouse also let me pick it up to clean the cage.
Is this weird and am I nuts to care about these little creatures? Any advice would be appreciated. Thanks!
A: Although I don't advocate catching wild animals for pets, I think what your daughter did was reasonable. Raising a native animal allows you to learn so much more about that species than would otherwise be possible and it gives you a whole new perspective that others, who have not had this experience, will ever have.
No, I haven't heard of people keeping field mice for anything other than scientific study but I see no reason why you can't do so. This is a wonderful opportunity for you to learn a great deal about this animal. You might want to get a field guide to mammals and see if you can determine exactly which mouse species you have. This will provide you with some additional information you can use to learn a bit more about the mouse. Obviously, you had a male and female. Let the mother care for the babies until they're weaned and then you can probably release them. You'll want to release them into appropriate habitat so they can survive. Maybe you already know where your cats caught them and can release them there.
As to your third mouse, I can't imagine that another mouse gained access to your cage - I think it must be a baby you never saw. Mice can have babies about every 6 weeks so think back whether this is a possibility. One thing to keep in mind, the mother will do best with her babies if all is kept quiet without much disturbance. If she accepts you and/or your hand, great but be sure not to upset her. Mice in captivity will sometimes kill their own young in a stressful situation. Don't want to scare you, just a gentle caution.
Sounds like you're doing just fine for your mice and I wish you well. I would like to suggest that you keep your cats in the house though or they'll certainly find other animals to "play with". Thanks for your interesting questions.
Posted by Shawna Campbell on March 08, 2005 at 02:16 PM
Q: Hi. I have a mother mouse that died during labour, and another that is due to give birth any day. If i give the pups to the other mom, will she be able to feed them even though she hasn't had her litter yet?
A: No, I don't think it will work. For one thing, the pregnant mouse's milk won't begin flowing until she actually has her own babies. Furthermore, it's unlikely that she would accept the other mouse's babies as her own anyway. Every once-in-awhile a female mammal will accept another's baby but this is not the norm.
Sorry I couldn't be more help!
Posted by Judy Welborn, on February 22, 2005 at 08:25 PM
Q: Just for fun, how much milk does a house mouse produce in 24 hours during "full lactation", that is, when her litter is exclusively breastfeeding (do mice "breastfeed") and eating no other solids? Also, what is the approximate volume of milk at each feed for each "mouselette". I look forward to your reply.
A: Oh my, you really want specifics! My wife is a lactation consultant and tells me that there really are people who measure mouse milk This is the site for one such piece of research - milk volumes on Day 15 ranged from 10 ml to 30 ml. : jeb.biologists.org
As to whether mice "breastfeed" - well, yes, all mammals nurse their young, but the words we use to describe it vary: Do they breastfeed, nurse, or suckle? Generally, we seem to reserve the term "breastfeed" for women and perhaps elephants and other primates, all of which have breasts. We probably use the term "nurse" for most other mammals. The choice of words might be different in other English-speaking countries though; in Australia, most would probably simply say mice "feed" their young.
Hope this helps. Thanks for your question.