Why is my rat mounting his/her same-sex cagemates?
This is a display of dominance. It is common, especially for juveniles, to express dominance by mounting. Usually, this insecure stage passes in a week or two. It is no real cause for concern, as the rats seldom hurt each other. The only cause for concern is if there is bloodshed while your rats are determining dominance. For females, this mounting is usually caused by their hormone surges, especially if they are young and in heat. Females have heat cycles every five days, so they’re pretty entertaining to live with.
