I have two male ferrets, one being several weeks under a year and the other 3-4 years. I just received my newest 3rd female ferret, she came with two others from a craigslist ad who are with my boyfriend.
The ones that came from Craigslist were not living in the best condition. There was feces and urine caked all over the Ferret Nation cage, no bedding, and some of the wire bridges weren't covered to protect their feet. All three are very personable and well mannered (except Ickis) from their previous-previous owner.
So i've had her for about 2 days and she's doing fine with the boys, but i've noticed she keeps peeing and pooping under the water bottle on the 2nd floor (i have 1 on the 2nd floor, and another on the 3rd floor) when i have set her feces and urine on the bedding of the 1st floor (i have a litter box already set for the boys, so they go in there for the most part already) but she still goes under the waterbottle on the 2nd floor.
Is there a solution to this, is this a habit she's gained from her previous owners? Or will this be another litter training, with catching her and moving her into the proper place with positive reinforcement?
The other two that my boyfriend has do not have this problem. Though, both of them i can tell are from an experienced owner by how much they love to be held and how they are already litter trained,
Ferrets generally poop wherever they want but they do prefer corners. I've litter trained mine by using the four corners of their cage as follows. In one corner I twist tied a small (cake pan size) litter box in place - so they couldn't scoot it out of the corner. In the second corner I put their bedding - don't like to poop where they sleep. In the third corner I placed their food and water. I blocked the last corner with a jug filled with water.
Having no corner to poop in other than the one holding the litter box, it quickly became their only alternative. As time went on, the litter box became their pooping place of choice. After that, they'd seek out the box where ever I put it.
Your new little girl will continue to poop where she's been used to doing it. Catching her and moving her is going to be a job, my friend, but you can try. But, I've never had much luck with that. Generally if their pooping place options are limited, they'll give in and use the box but to be successful, they must learn to do it on their own.
Just from what you've told me, you are a great ferret owner; lots of love and patience. Your fuzzy little friends are quite lucky to have you.
Sorry I couldn't be of any more help. All I can offer is trying my suggestion, or a variation of it, and see what happens. And please don't despair, some ferrets are never litter trained.