Thinking of building an outdoor roost for guineas and some game hens. Thought about a raised roost with metal poles do keep climbers out. I have had a couple in a tree that are doing fine but I know they are not safe by anymeans.
I think the raised roost and metal poles will work fine but as an added safety measure I would use some inverted metal cones so predators cannot climb up or some flashing wraped around the pole, the slick surface will be impossible to grip.
We had racoons reaking havoc on our birdfeeders this year. To solve our coon problem with the bird feeders we slid a downspout over the bird feeder pole. They haven't gotten past that yet and its been about 5 months now. I think they gave up. Would have loved to seen that on video when they first tried to climb it and couldn't.