Hi Palladium
I don’t think you can have thought your poisoning a rat in a cage through. It would be an incredibly inhumane thing to do and as you are clearly an animal lover (otherwise you wouldn’t be worrying about the hogs), if you thought about it carefully, I don’t think you would want to do it. The poison wouldn’t work immediately and the rat would suffer a slow and horrible death made very much worse by being trapped in a cage and potentially without access to water. Whatever anyone thinks about rats, they are actually quite intelligent animals and they really don’t deserve that.
In my experience it is usually the bird food which initially attracts rats and perhaps your best course of action is to make sure that the rat can’t access any of the food. If it doesn’t get any food, there is not much point it hanging around. I have written above about things I have tried, usually successful in the end to make things difficult for the rat and suggest you try something along those lines. At this time of year, when there is beginning to be more food around in the wild for the hogs, you could easily confine their feeding time to 2 or 3 hours a night, when you can watch them and scare the rat away. If you try this, you will probably find that watching hogs in real time is so much better than just watching on video. It also has the added benefit that the hogs seem to learn when the food is available and time their visits accordingly. It has been my habit to feed the hogs in this way, for many years and they have always done fine. It leaves them with the opportunity to forage in the wild as proper wild hedgehogs whilst at the same time having some additional food if they need it.
I recommend you try the deterring path before considering anything more drastic. Good luck. Let us know how you get on.
