I like to keep dry cat food out all the time now that I have growing kittens in the barn. I also supplement the kittens' intake with a little canned food in the evening, which the two of them devour in about two minutes as I watch.
I check their dry food when I'm out there giving the babies their treat to see that they have something to eat through the night. For the last two or three weeks, when I go out next morning, there isn't a single crumb of food left in their pan. The cats never clean up their food to that extent. There have always been a few pieces of food left in the morning.
Furthermore, I have gotten in the habit of putting a paper plate in the bottom of the pan before I put cat food in it, and not only was the food gone, but the paper plate had been pulled out of the pan! Cats would not do that, but varmints will. I figured raccoons were the most likely suspect, since they like to use their little "hands" to move things around... you know, things like a paper plate. Just checking to see if there's a crumb under there, no doubt.
We have a Havahart trap, and discussed setting it up in the barn. However, there's no doubt in my mind that there would be a cat in it next morning rather that a raccoon. Maybe not the old cats, since they've each been trapped in there once and seem to have learned their lesson. But the kittens, as kittens will do, would go in the trap just because it would look to them like a space they hadn't yet claimed, a new box to play in. They'd get caught, for sure. I could put them in a cage for the night, but I really hate to do that to them.
i have some past experience with varmints, so I have a strong feeling that if someone would wait until half-an-hour after dark and went out silently with a gun, the possums would already be at the buffet ready to shoot. Once possums and coons find out there's going to be steady access to good food, they don't waste a lot of time getting there. We once killed multiple chicken-killing possums with this method. If they hear a voice, they run. But keep your mouth shut, get there with someone to shine a light on them, and they are easy targets. Unfortunately, I don't use guns, and "someone" isn't usually interested in sneaking out into the dark once he's taken off his shoes for the night.
I noticed something else that convinces me raccoons are the culprits: The water dish I keep in the barn for cats is rapidly filling up with wet cat food. Why? Because the little varmints like to wash their food, and this water is conveniently located next to the pan of food.
For tonight, I intend to put the cat food pan and its contents in a safe place. At least the pesky creatures won't be rewarded for their long trek from the woods to the barn. I have set an alarm on the Amazon Echo to remind me of this, since I've been forgetting to shut my chickens up lately. And if I'm forgetting that, I would surely forget to put the cat food up too.
I'll let you know how things work out.
Peace... unless you are a raccoon reading this. If so, I wish you no peace at all.