Why are your two female rabbits fighting?

Does (female rabbits) will mount each other as a sign that they are ready to breed. Males will also mount each other in their puberty age as a way of establishing dominance.

Rabbits of both sexes sometimes mount another rabbit as a show of dominance. One female mounting another is trying to assert dominance. Keep an eye on your bunnies and separate them if it turns to fighting.

Rabbits can be kept in the same cage if they're bonded. Usually this means the rabbits must be neutered/spayed - but, in some cases, when they've been raised together, female rabbits can be kept together even when they aren't spayed, and they won't fight. When rabbits are bonded, that means they don't fight and are affectionate. The bonding process can take anywhere from a couple weeks, to many months of patience and hard work.

See the related questions below for more info and links.