Rats and mice may seem similar at first glance, both being rodents and popular pets. Pet rats belong to the Rattus Norvegicus species (brown rat), while pet mice are classified as Mus Musculus.
Despite their physical resemblance (except for size), rats and mice are very different creatures. This might lead some to believe they can coexist in the same cage, but in reality, they should never be housed together.
Can You Keep Rats and Mice Together?
The simple answer is no, you cannot and should not under any circumstances.
The main reason for keeping rats and mice apart is that rats will hunt and kill mice if given the opportunity, and may even consume them.
This behavior is not due to rats being malicious or aggressive (in fact, they make wonderful pets and are usually very affectionate), but rather it’s instinctual.
In the wild, mice are preyed upon by rats because they compete for the same resources such as food and territory. Mice are inherently fearful of rats (even more than larger predators), and the mere scent of a rat can cause immense stress and fear in mice.
Rats will naturally pursue and harm mice due to this dynamic, so it is crucial to never house them together, not even in separate cages within the same vicinity.
Although both are rodents, rats and mice have distinct care requirements. If you are considering keeping either as a pet, be sure to research proper husbandry practices to ensure their well-being. You can refer to our rat care guide and mice care guide for more information!
Can I Keep Rats and Mice as Pets at the Same Time?
You can have both rats and mice as pets simultaneously, but they must always be housed in separate cages and kept in different areas.
As mentioned earlier, rats have a natural inclination to hunt mice, so the mere presence of a rat’s scent can cause significant stress for mice, leading to potential distress for the rat as well.
This applies to free-roaming situations as well; never attempt to allow rats and mice to roam freely together as it often results in aggression and harm. Avoid any attempts to introduce them to each other.
If you handle rats and mice consecutively, washing your hands can help minimize the transfer of scents and keep each rodent calm. Additionally, providing separate toys and cage furnishings for rats and mice can aid in reducing stress levels.
It is advisable to only keep one type of rodent at a time—either rats or mice—to minimize the risk of harm or unnecessary stress to either species. Our article can assist you in evaluating the options when considering rats or mice as pets.
Can Rats Cohabit With Guinea Pigs, Hamsters, or Other Pet Rodents?
Rats (or mice) should not be housed with any other species of rodents.
Factors such as size differences, natural predatory instincts, varied dietary needs, and distinct housing requirements all contribute to the necessity of keeping rats (and other rodents) separate from different species. However, social rodents should always be housed with their own kind. An exception to this rule is solitary rodents like hamsters, which prefer to live independently.
Since rats do not coexist with other rodent species (including mice) in the wild, they should not be housed together as pets. One exception to this rule is African Soft Fur Rats.
Mice and African Soft Fur Rats
Despite their name, African Soft Fur Rats are actually multimammate mice (possessing 18 nipples!) and due to their close relation to fancy mice, they may occasionally cohabitate with them.
While rats should not share living spaces with them, ASFs can coexist with mice if introduced carefully and gradually, with ample supervision and consideration for their individual needs.
ASFs are social creatures (similar to mice and rats) and thrive in groups of 3 or more. Some success has been seen in housing ASFs and fancy mice together in groups, and if they are of opposite genders, there is no risk of unexpected litters as fancy mice and ASFs cannot interbreed (though avoid keeping unneutered males and females of the same species together!).
The ideal ratio for this combination would be one male fancy mouse to two or more female ASFs or a group of female fancy mice and ASFs.
FAQ
No, rats and mice are different species and will not mate as they are not attracted to each other. The protective covering on their eggs prevents the sperm of another species from fertilizing them.