Last year I noticed a mother ringtail possum and her 2 kids using the balcony of my house as a walkway to get to the nearest trees. They were not living in my house at that time. For a while after that I lost sight of these possums.
Last night, while I was looking out of my kitchen window, a ringtail possum walked across the window sill carrying what looked like nest-building materials wrapped in its prehensile tail. Ringtail possums are almost never found nesting in houses – they much prefer trees, so I was curious.
Next morning, I went outside and examined the walls of my house, especially the space between the top of the wall and the roof. Sure enough, there is a possum nest on top of one wall. I took out the ladder and climbed up to have a better look. There were 2 possums living in it, possibly the juveniles I saw last year. Evidently they have decided the rolled up plastic lattices I put up to prevent blackbirds from nesting there make an ideal possum nest.
You can go here to see more pictures of these cute, furry animals.