fighting cat

Cats are territorial animals and they will often fight to defend what they believe is their territory. This is most common with cat fights that happen outside the house, where your cat believes another cat has encroached on their land. Alternately, a feral cat could believe your cat should not be here. But such fighting is also common among cats who live together. Cats mark their territories with scent, and your house is no exception. If you have more than one cat living at home, they will often fight about this issue.