Naturally enough, later in the evening, the ants were all over the new plate, too. Now, of course we don't want to put some kind of poison next to, on or around our cat's food, but I know that cinnamon oil is an effective ant deterrent... but I have no cinnamon oil at the moment, so I figured I'd try regular old ground cinnamon and see how that does.
It does very well, but, of course, you have to surround the food supply, not just one access point to it. Okay, so another new plate later is now sitting on a small pile of cinnamon. Great.
Now, the ants can't get to the cat food, but the cat seems not to appreciate the strong scent of cinnamon seasoning her food. She's giving me that look that says, "Hey, bitch, what gives?" And you know when a cat calls you "bitch" it's not a compliment.
So I figured I'd try something different: around the bottom of the bowl, just near where it touches the floor, I traced a line of cooking oil, onto which I then sprinkled cinnamon. Now, hours later, there is less food in the bowl, making me think kitty is putting up with the lighter seasoning of cinnamon, and there are no ants at all, making me think my experiment is a success!