Why are my two cats fighting?

i have two male fixed cats. A outside cat was looking in my sliding glass doors and crying to my cats. my cats typically always get along. I opened the door (there is a screen there and my cats hissed and my cats go in a cat fight. I had to separate them and got scratched up. What the heck was that about. My guys get along good and one just went off on the other. Any idea why? Jamie

Also, why are cats crying outside my door?

Reply
Hi
This is probably due to fear of the stray cat outside which has caused your cats to fight. It is a strange issue called aggression truama. Please see this page for more information on this behavior here

cat-aggression-trauma.html

As for why other cats are coming calling well sometimes un neutered cats can become confused and just call for all cats thinking that there may be females around too. It is also about challenging for territory too as this is what drives cats. You may want to try spraying around your doors outside with a strong citrus smelling liquid to try and keep the other cats away.

best wishes kate

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