My 4 year old cat, Sasha, and my newer cat that I rescued two months ago, Pequena, in the past week have been doing what I call "extreme fighting". Before this, they did fight periodically but it never got that bad. In the past week, I have seen them have 4 really bad fights, and my roomate witnessed 2 other ones when I was not home. Usually my cat is the more aggressive of the two, and she started the first couple that I witnessed, but my roomate said that Pequena started the one last night. She went up to Sasha for what seemed like no reason and started hissing at her and attacked her first.
When they get into these "extreme fights" they chase each other around the apartment so fast and aggressively, they knock over a lot of things, running in and out of the windows, fur is flying, alot of hissing from both of them. I am amazed that so far neither of them has gotten mauled with the claws by the other one.
Is there anything I can do to try to stop this behavior? I am afraid that eventually one of them is going to get seriously hurt and will need vet attention. I am particularly worried this might happen while no one is at home.