Help! Strange cat coming through our cat flap

[Wazimu]

We have a three-year-old female cat who has been neutered. She has a magnetic cat flap to allow her to come and go as she pleases, day and night.

However, increasingly over the past three months, we have been getting up to find another cat, of unknown ownership, asleep on the carpet or armchair.

When we enter the room, the cat flies out through the cat flap. We believe it is a male because we believe it has sprayed and created a smell and we were told that male cats do that.

This stranger does not wear a collar and the cat flap cannot be forced from the outside, so we suspect that the stranger mews outside the cat flap and our cat gives it entry by going out and then being followed in before the flap closes properly.

We are not too worried about our cat making new friends but we don't like the stranger's dirty habit.

Any suggestions? Is it true that once a male cat has been sterilised, it no longer sprays? That could be one solution - if I catch it and take it to the vets to be sterilised.

Help!

My cats neutered and he sprays, females can spray too.

Get a microchip controlled flap, it reads your cats microchip and only let's her in.

Thanks Fluffycloudland77. The problem is that we think that our cat goes out and allows the other cat to tailgate her back in. I am assuming that she would still be able to do that even if our cat was microchipped.

First off - I don't currently have a cat flap. (Elderly housecat.)

However, from a quick look see, I've noted that it seems that magnetic cat flaps can be much looser in the way that they work so that if your cat was sitting by the door when intruder came calling (in preparation for hostilities for example) then the magnetic cat flap would 'read' her collar and open itself even from that distance - thus allowing the intruder in.

Microchip cat flaps seem to have a much tighter range of operations and it would need to be a seriously hot pursuit rather than just a 'hanging out' on her part. Much rarer.

Might be worth doing some experimentation with her collar around and seeing if this holds true for you?

I know other people on here do have them to stop intruder cats coming in, maybe one of them will post oo.

We had cats coming in when I was little, you'd come home to find the ginger boyfriend staying.

We have a microchip cat flap (petporte) and our intruder just bashes his way in, cheeky bugger. I wouldn't mind either except he also sprays. He is the bane of my life.

So do read reviews before buying a microchip flap as they are not foolproof.

petporte is not the recommended one here, Tea. Most posters have Sureflap which seems to be a much superior product. Some of them may comment later.