"jr via CatKB.com" <forum@nospam.CatKB.com> wrote:

Definitely clip their claws. Clipping the aggressor's claws might
be best if you know which is the aggressor. Otherwise, clip them
both. Clipping is probably most easily done upon waking your cat
up from a nap. There is a whole lot of difference doing it then
compared to doing it when the cat has been awake and alert.

If she wants to get away, maybe you should make sure she has a
collar/tag just in case she gets outside. If she does not hurt
him, do not clip her claws. Accidentally getting outside with
clipped claws is not good. I guess you expect your male will not
run away.

If I were in your shoes, I might expect those two cats to get
along. One would think that having another same type creature
would provide companionship. Much to my surprise, apparently some
cats do just fine without other cats around. Arg. Interestingly,
your male is growling at your female. My female of about seven
years in the same situation as your male, was upset with a new
male. Over a year later, she still does not like him but she
tolerates him now. If I were you, I might show your male cat lots
of affection. But do clip his claws if he is the aggressor.
Attention might not make him like the female, but it might make
him feel better.

I would like to know how things work out after a few months. Good
luck.

<snip>

A week sniffing through the door is enough.  Clip their nails and open
the door.  Let her come out on her own but make sure she has a safe
place to hide if she should be attacked.  There will ge growling and
spatting but after a few days, they will settle down.

I have always don this on the weekend when I could be around to
supervise the introduction.  If you have to be gone all day at work,
wait to do this until you can be home with them.

good luck,
-L.

Reversing is a good idea, also feed them at your meeting-point door if
possible.  Also wipe each cat with a separate cloth and place it in the
'other room' to familiarise the other cat with the scent.  Bring the cloths
closer to the feeding station as well over a period of several days at
least.

Open the door wider and wider.  Introductions like this can take a week or
two, don't rush them.  There may even be some aggression when they finally
meet, but that is quite normal, a hierarchy has to be established.  Search
for 'cat introductions' on google.

A summary of what I saw on the net, and based on my own recent experience:

The newcomer should be placed in a cage or large pen in a separate room for
about a week. No face-to-face interactions allowed during this first week.

Put the resident cat in a separate room and let the newcomer roam the rest
of the house. The idea is to mix their respective scents and get them used
to their respective scents.

Use separate kitty litters at first.

After a week, let the cats meet face-to-face through the bars of the pen or
having the newcomer in a carrier. There may be a few hisses, but see if that
diminishes and they start chatting with each other.

Continue these introductions through the pen or carrier until there's no
hissing.

With no food in the room, and all doors closed, let the newcomer out of
his/her pen carrier and see whether the cats are friendly. Supervise the
whole time.

After they become friendly, or maybe as they are becoming friendly, set two
dishes of food at opposite ends of the room. Let the two cats eat in the
same room together, from separate dishes. Supervise.

Similar approaches are described at the following:

http://www.fourpaws.org/pages/adopting_pages/introducing_cats.html

http://www.cuhumane.org/topics/catcat.html

http://www.fabcats.org/introducing.html

http://www.thecatsite.com/Cats/Cat_Behavior/Introducing_Cats.html

I like the idea of changing the cats in the rooms - it will give the
female a chance to explore your house and will give the male a chance to
become even more familiar with the scent of the female. Just be sure
they can't get to one another during the change. Also, I think the idea
of putting the latch on the door so it can open a little bit is a great
idea. Best of luck with the pair!

KR2T