Indoor Cat Territiorial towards Outdoor Cats

Question
My cat Roxy is a female spayed American Shorthair.  She loves to perch next to open (screened) windows and look outside.  Today she saw the neighbor's outdoor cat perching on the fence and she began hissing.  I immediately closed the window and blinds, and scared the outdoor cat away with water.  

What can I do to keep the strange cat away, and/or to calm Roxy down if it comes around again?  Keeping all the windows closed indefinitely is not an option, but I don't want Roxy to break the window screens and get into a cat fight.  Also, I am concerned about the possibility of redirected aggression towards me or other family members.  Roxy is not a biter, but when she was hissing today, it looked very likely that she might displace her anger onto me.

Answer
Amy,

When a cat is territorial and can't get to outside cats in 'her' territory to defend it, she can turn on the animal members of the household and fight with them. In her mind she is fighting the other cat not the household pet. If no pets are around she MAY turn that aggression on people.

If it is not stopped, she can develop a permanent personality change. She may also start eliminating improperly....because of stress or to 'mark' her territory inside.

You need to block the window that she can see the stray cat out of, at least viewing ouside height.

When she gets like that, it's best to lock her in a room for about 4 hours with no contact so she can calm down.

There are calming aids that you can use for her also:

"Bach's Rescue Remedy" is extremely effective in the relief of stress or trauma, both in humans and in animals. Two or three drops in a bowl of water often provide quick relief. If your cat does not like the taste (the alcohol content is almost negligible after dilution), you can rub one or two drops behind the cat's ear. People who have tried Rescue Remedy on their cats, swear by its effectiveness. You can get it at a people's health food store or online.

"Feliway" spray is a "friendly pheromone, developed by Farnam, Inc. It mimics the facial pheremones cats use to rub against things and leave their scent (which is calming to them). Feliway is believed to be effective in reducing  stress-related behaviors. Or "Comfort Zone with Feliway" is a wall plug-in which diffuses the pheromone throughout a room. You can get it from a vet (they use it too), PetSmart, Petco, etc., or online.

If your cat is still being very stressed the vet can put her on "kitty Prozac" for a short term (usually 2 weeks) until she calms down. It is a common prescription for cat's stress and/or emotional issues. You may want to speak to your vet about it.

I am including links to 2 good articles on Redirected Aggression that may be helpful to you:

http://www.sniksnak.com/cathealth/aggression3.html

http://www.littlebigcat.com/index.php?action=library&act=show&item=redirectedagr...

I hope this helped answer your question.

Tabbi