Mice use their bodies to communicate with each other and their human companions. Here are some behaviors you may see in your mouse and what they mean.
If you see a mouse wagging its tail at another mouse — especially if both mice are un-neutered males — a fight it likely to follow. Mice use tail wagging as a warning they are about to attack.
Mice that are under stress may gnaw off their own hair, leaving bald spots. This behavior also involves male mice, which gnaw off the hair of subordinate male mice. The hair is usually taken off the face.
Mice that live together take turns grooming each other in hard to reach places. This behavior is a sign of camaraderie.
When mice are under stress, they sometimes groom themselves obsessively.
Mice have been known to eat the body of a dead cage mate. Mice do not kill each other for food, but are scavengers and will eat a carcass if they have access to it.
Mice instinctively gather materials and make nests to sleep in. If you see your mouse carrying bedding to one corner of the cage, it is building a nest.
Young mice are the ones most likely to exhibit play behavior. They will chase each other around the cage. (You know it’s play and not aggression because no one gets hurt.)
When mice are stressed out, they groom themselves excessively, hide, sleep more than usual and run wildly about their cage. If you see these behaviors in your mouse, your small pet may need quiet time in a darkened room, away from whatever is scaring it.