I got a rescue cat a couple of months ago, a timid 4 year old girl. She has always been a house cat but the shelter advised she could go out. In the last couple of weeks I've been letting her in the garden, she explores for 10 minutes then comes back in (though the back door which I leave open a bit).
All fine, but now I have put a transparent cat flap in. She doesn't know it's a door yet, she treats it as a window, it's locked as I don't want her to use it yet. I let her out the other day, then heard yowling from the garden, and saw she was cornered by a tom. I went out and got rid of him. She seemed ok, not too scared - stayed out a bit longer by herself then came back in.
But now 2 neighbouring cats are aware she exists, and come up to the cat flap at night. I woke up last night to hear the cat flap being bashed, and lots of yowling and hissing. I had covered up the flap with a big bag of litter, but my cat had dragged it away. I'm scared it will just break one day/night.
She lived with 3 other cats before rehoming and the rescue advised that in conflict situations she hides. She seems pretty feisty to me though with other cats!
Do neighbouring cats eventually give up when they realise they can't get in? It's a microchip cat flap.