There is a story from Cornwall, UK, online this morning which reminds me of the difficulties of dealing with a neighbour’s cat who likes to come into your home and eat your cat’s food and then calmly leave as if they are attending a hotel buffet.
The story on the website Cornwall Live portrays the amusing side of a cat “stealing” food from another house. The cat in question, Max, even stole a whole chicken from the windowsill of a neighbour’s house where it was cooling down. He didn’t get far but the intention was there. Max lives with Patricia Grundy.
The neighbours accept him but here’s the problem. Max has become fat and the neighbours’ cats have lost some of their food and their owners are complicit in the problem. The point that I’m making is that the neighbours accept that Max can eat their cat’s food which means Max get bigger and the neighbours are funding his drive towards obesity.

Obesity
It is a tricky problem to solve. Max’s owner is quite amused by the whole thing but her cat has become obese and obesity is a health problem. These cat thieves tend to have a food addiction. They need to be stopped. What can she do? What will she do? She won’t confine her cat to a catio or a back garden enclosure. That means she will allow Max to roam around the neighbourhood as he pleases, as before. Nothing will change from Max’s perspective because his owner accepts his behaviour. One issue may be boredom. It seems to be a feline version of food therapy which is commonplace in humans. Perhaps she could stimulate her cat more through play. This would also help with weight loss.
Microchip triggered cat flap
The owners of the other homes also accept it but they could do something about it. They could fit cat flaps which are only triggered by the microchip inside the home owner’s cat. This prevents other cats entering. This would be a 100% solution. These sophisticated cat flaps are not too expensive on Amazon. It may be possible to fit it into the existing hole because many of these cat flaps require the same sized hole. This would reduce the cost. I know that the cost and the hassle is a barrier to taking this action.
Make it uncomfortable
An alternative is for the neighbours to make it uncomfortable for Max to enter their homes. This should be done with sensitivity but cats will respond to being shooed away and will learn that they are unwanted inside another person’s home. It does depend upon the individual cat obviously. And they will come back but they will learn. If they come at night the problem is almost impossoible to fix.
I have this exact problem myself and I have experienced it before. When it happened before the owner of the invading cat complained that I was feeding her cat. In this instance there is no such complaint but I have gently rejected the visitations by shooing her away. She visits less often and understands that she can visit but she can’t eat.
Transmission of disease
There is another issue which is worth noting. You don’t know how healthy someone else’s cat is. What if the visiting cat has a chronic illness which is transmitted through their saliva? For example, FIP is transmitted through infected secretions. Also feline leukemia virus disease complex is transmitted in infected saliva. These are both very serious diseases. If they eat from the same bowl as your cat in your home they could transmit a serious disease to your cat. This is probably the most important aspect of this conundrum and the major reason why you should fit a catflap which is triggered by your cat’s microchip.
Some more on cat flaps

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Useful tag. Click to see the articles: Cat behavior

Pawly Door with prey detection is a smart cat flap which will arrive shortly

Infographic on cat (doors) are a mixed blessing

Cat flap that required planning permission before installation

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