Calvin wrote:
I can stop the stray's aggression by
yelling and clapping my hands, but I scare
the other cat too, so he runs away.

And this is where the problem lies. You are using negative reinforcement
which does NOT work. When you yell the stray associates that with the
presence of the other cat and becomes resentful thinking that the other
cat is to blame for the yelling and loud noise, and this only makes him
more intent on being aggressive to the other cat. It becomes a vicious
circle.

The way to handle this is to use distraction and praise. You want the
stray to associate only good things with the presence of the other cats.
Anytime you see something happening or starting to happen, do not yell
or do anything negative. Instead get the stray's attention using a calm,
happy voice and then pet and praise him in the presence of the other
cats, even if he has just been aggressive. Make a point of giving the
stray positive attention or treats at other times when he is in the
presence of the other cats. You must be consistent doing this and you
will start to see the problems lessen to a point where they are
eliminated altogether or minimized to a tolerable level. I have use this
method *many* times in a house of 25 and it works. It wouldn't hurt to
get a Feliway diffuser and some spray to help things along, either.

Megan



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